Guide to the Selection and Use of High Performance Stainless Steels

Soon to be published .. NiDI Nickel Development Institute

GUIDE TO THE SELECTION AND USE OF HIGH PERFORMANCE STAINLESS STEELS

Metallurgy - Properties - Corrosion Performance - Fabrication

A Nickel Development Institute Reference Book Series No. XX XXXX

Page 1 9/3/99 TABLE OF CONTENTS INTRODUCTION ...... 3

CLASSIFICATION OF GRADES ...... 5

AUSTENITIC HIGH PERFORMANCE STAINLESS STEELS ...... 5 FERRmC HIGH PERFORMANCE STAINLESS STEELS ...... 9 DUPLEX HIGH PERFORMANCE STAINLESS STEELS ...... 10 PHYSICAL METALLURGY ...... 13 PHASE RELATIONS IN THE IRON-CHROMIUM-NICKEL SYSTEM ...... 13 SECONDARY PHASES ...... 17 KINETICS OF PHASE PRECIPITATION REACTIONS ...... 21 AUSTENITIC STAINLESS STEELS ...... 22 FERRmC STAINLESS STEELS ...... 24 DUPLEX STAINLESS STEELS ...... 26 MECHANICAL PROPERTIES ...... 28 AUSTENmC STAINLESS STEELS ...... 29 FERRITIC STAINLESS STEELS ...... 31 DUPLEX STAINLESS STEELS ...... 33 PHYSICAL PROPERTIES ...... 34

CORROSION RESISTANCE ...... 36 RESISTANCE TO INORGANIC ACIDS .37 RESISTANCE TO ORGANIC ACIDS .43 RESISTANCE TO ALKALIES AND ALKALINE SALTS .46 CHLORIDE- AND OTHER HALIDE-CONTAINING AQUEOUS ENVIRONMENTS .48 NEAR NEUTRAL ENVIRONMENTS - NATURAL WATERS AND BRINES .53 INFLUENCE OF MICROBIAL ACnVITY .57 OXIDIZING HALIDE ENVIRONMENTS - CHLORINATED COOLING WATERS AND BLEACH SOLUTIONS .58 ACIDIC ENVIRONMENTS CONTAINING HALIDES- FLUE GAS CONDENSATES .61 STRESS CORROSION CRACKING ...... 65 WATER AND BRINE ENVIRONMENTS ...... 66 SOUR OIL AND GAS ENVIRONMENTS ...... 70 HYDROGEN ENVIRONMENTS ...... 73 CORROSION ACCEPTANCE TESTS ...... 74

FABRICATION ...... 78 HOT WORKING ...... 79 COLD WORKING ...... 81 ANNEALING ...... 83 MACHINING ...... 86

WELDING ...... 87 AUSTENmC STAINLESS STEEL GRADES ...... 89 FERRITIC STAINLESS STEEL GRADES ...... 92 DUPLEX STAINLESS STEEL GRADES ...... 93 SURFACE CONDITION ...... 97

APPLICATIONS ...... 98

Page 2 9/3/99 Materials Workshop for Nuclear Power Plants Stainless Steel and Nickel-Base Alloys Presented by Mr. Curtis W. Kovach Dr. Nicole Paulus-Kinsman of the Nickel Development Institute (NiDI)

Workshop Schedule

8:15 am Welcome and Introduction

8:30 am Basics of Stainless Steel and Nickel-Base Alloys

9:30 am Corrosion Basics 10:30 am Welding Stainless Steel 11:30 am Lunch 1:00 pm High Strength Stainless Steels (Discussion)

2:00 pm Advanced Stainless Steels 3:00 pm Microbiologically Influenced Corrosion 3:45 pm Conclusion

The format for this workshop is flexible and open. Questions may be asked at any time and examples from the floor can be discussed during the session or one-on-one afterwards.

September 9, 1999 NIDI NUCLEAR POWER PLANT WORKSHOP

Conpany US Nuclear Regulatory Commission

Location: Rodville. Maryland Date: SeptLeSt9

High ATTENDEE INFORMATION N0CE Perfromance Mailing List Stainless Steel Book

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Curtis Kovach RUJEDI Consultant NICKEL DEVELOPMENT INSTITUTE Technical Iarketing Resources, Inc. 3209 McKnight East Drive Head Office Pitsburgh, PA 15237-6423 U.S.A. 214 King Street West, Suite 5 10 Toronto, ON Canada M5H 3S6 Telephone 412-369-0377 Telephone 416-5917999 Fax 412-367-2353 Fax 416-591-7987 ckotuch8trnr-inc.cosn

Dr. Nicole Paulus K, I7~~I~bDIPo"D I Consultant NICKEL DEVELOPMENT INSTITUTE Technical Marketing Resources, Inc. 3209 McKnight East Drive 1Iead Office Pittsburgh, PA 15237.6423 214 King Street West, Suite 510 U.S.A. Toronto, ON Canada Mll 3S6 Telephone 412-369-0377 Telephone 416-591-7999 Fax 412-367-2353 Fax 416-591.7987 npaulus6tmrinc.com "1 1 "1- J L L NiDI NUCLEAR SERVICE WATER PIPING CASE STUDY No 15002 Table I 1994 OSKARSHAMN NUCLEAR System Description POWER PLANT, FIGEHOLV1, SWEDEN DESCRIPTION UNIT 1 UNIT 2 UNIT 3 Start Up 1972 1974 1985 Coastal nuclear power plants, which use brackish and System Testing 1970 1972 1983 often polluted water in their service water systems, face Power Output (MWc) 460 620 1.210 one of the most demanding service environments in the Regular System 700 1,000 1,700 Flow Rate (kg/s) industry. The Swedish utility OKG AKTIEBOLAG has Emergency System 25 400 700 this operating environment at their Oskarshamn Nuclear Flow Rate (kg/s) Power Plant in Figeholm, Sweden. The brackish, Main Condenser 20,000 26.000 45,000 polluted Baltic Sea water used in the service water system Flow Rate (kg/s) caused extensive corrosion of the original system materials. Material replacement, testing, and evaluation emergency service water system in all three plants is nor- have been on-going since 1978 giving OKG some of the mally only operated during shut-down periods. A most extensive operating experience with 6 Mo austenitic constant low flow rate is maintained through the system stainless steels, titanium and other high performance when it is not in operation to prevent water stagnation. replacement materials of any nuclear power plant in the The emergency systems in all three units were designed world. This case study reviews the problems experienced so that, even if the pumps stopped, the operating system with original system materials; replacement material eval- would never be empty. The return pipes go to the highest uation programs; and actual performance of the alloys in point in the system. service; therefore, providing valuable insight for utilities with equally severe operating environments. The open sections of the service water systems use brackish, polluted water from the Baltic Sea. The water enters the plant through culverts and is pumped through a short THE SYSTEM section of underground piping before entering the units. The closed portions of the service water system use demineralized water. Units I and 2 have open, once- The Oskarshamn Nuclear Power Plant has three operating through service water systems in all but the reactor units. The start-up dates for these units and other basic building, which has a closed system. The majority of the operating data for the service water system can be found piping and over 100 heat exchangers in these units are in in Table 1. The units all have open emergency service the open portion of the service water system. These are the water systems and have both closed and open once- older units with start-up dates in 1972 and 1974, through portions of their regular service water system. respectively. Corrosion problems became evident in both The condensers in all three units are fed by the open units within two to three years after commencement of portion of the service water system. commercial operation. The first problems arose in the Both the standard and emergency service water system main condensers. These were followed by problems with piping was originally rubber-lined carbon steel. The the heat exchangers, and then, with the piping. Unit 3, which began operation in 1985, has both closed and open any portion of the system. It is possible that the low water temper- sections in its service water system with eleven titanium plate heat ature during much of the year has prevented a MIC problem. The exchangers made by Alpha Laval as the interface between them. water source and description have not changed since initial testing Since this unit is fairly new and since titanium was initially installed of the system. in both the heat exchangers and the condenser, there have been no significant corrosion problems to date. Corrosion problems with the During July and August, crustaceans can accumulate in the system. pipe are anticipated when the rubber lining begins to crack or wear. At one time, a trial study was done in which hypochlorite was added to the service water system to prevent crustacean growth. Although this worked well, the use of hypochlorite additions was not adopted THE WATER by the plant because of environmental concerns. No additional chlorine or other chemicals are currently added to the water except The brackish, polluted water used in the open, once-through por- during system shut-down. A cathodic protection system is used to tions of the service water systems is drawn from the Baltic Sea. All prevent deterioration of the condenser tubesheets and waterboxes. three units were tested two to three years before the unit start-up date

Table 2 MATERIAL EVALUATION Water Description AND REPLACEMENT

Source Baltic Sea Oskarshamn selects materials by reviewing technical literature, lab- Type brackish, polluted 0 oratory tests, and actual in-plant experience. The laboratory based Temperature 0 - 20'C (32 - 72F) testing program is sponsored by Vattenfall, the Swedish State Power pH 7.5 -8.0 Board, with financial support from participating power stations. The Chloride level 4,000 ppm testing program simulates the corrosion and erosion problems Magnesium level 250 ppm common to the participating plants but at an accelerated rate. The Calcium 100 ppm materials included in the program are titanium, SAF 2507® Silica 0.8 ppm (UNS S32750) duplex stainless steel, 254 SMO® (UNS S31254) and 654 SM0® (UNS S32654) austenitic stainless steels. All the stainless steels are produced by Avesta Sheffield AB. The samples and may have had some stagnant water in them during that time. are evaluated on an annual basis. Oskarshamn also closely monitors the performance of those materials already in service during the reg- The basic characteristics of the water supply are outlined in Table 2. The high chloride content of the water and presence of pollution ularly scheduled inspection program. would be highly corrosive to many alloys. The increased solubility Initial material replacement began in 1978 when a large number of of oxygen at lower water temperatures and the increased corrosion aluminum brass heat exchanger tubes in Units I and 2 were replaced rates that normally result under these conditions are probably an with titanium. The replacement program for Units I and 2 has been important contributing factor to the plant's problems. The facility is on-going since that time. Subsequently, the rubber lining on the not aware of any microbiologically influenced corrosion (MIC) in carbon steel pipe began to crack (due to age) and wear away. As the

Table 3 Underground and In-Plant Replacement Materials

254 SMO 1984 1985 1986 1987 1988 1991 TOTAL COMPONENTS 1 . _ _ Pipe . 1 length i m 26 160 48 36 146'1' 42 458 ft. 85 524 157 118 479 138 1,500 diameter mm 206-306 60-408 206 206 60-168 306 in. 8-12 2-16 8 8 2-7 12 Elbows 907 2 15 12 9 75 4

Cone Pipe Fttings 2 l l - | _ T-pieees l - | 2 i Condenser Tubes length m -- 54,000 54,000 1t. - - 177.120 177,120 diameter mm - - 24 ft. - - - . - 0.94 TITANIUM 1978 1979 TOTAL COMPONENTS Condenser Tubes lenghth m 288.000 540,000 ft. 944,640 826,560 1,771,200 diameter mm 24 25 in. 0.94 0.98 carbon steel is exposed to the service water, it corrodes quickly, intermediate cooling system is in the reactor building. Unit 3 was making replacement of problem sections necessary. 254 SMO, a built with only eleven plate heat exchangers exposed directly to 6% molybdenum stainless steel, has been the replacement material service water. It also has several closed loop intermediate cooling of choice for pipe, tube and other system components since 1984 systems for localized components which use demineralized water. because of its corrosion resistance, availability and strength. Unit l's and Unit 2's heat exchanger tubes failed faster than Although titanium also provides the necessary corrosion resistance, anticipated because of the high water velocity. As of 1991, Unit 3's it is more difficult to weld than 254 SMO stainless. Increased inert titanium heat exchangers have not required replacement. gas shielding is required, and skilled titanium welders were difficult to obtain. The higher strength of 254 SMO stainless was also an The tubes and tubesheets in fifty heat exchangers in Units I and 2 important factor in its selection. have been replaced with titanium. To avoid the vibration problems which can be caused by the modulus difference, six support plates Table 3 provides a summary of the titanium and 254 SMO stainless were added to each "church window". The titanium has performed installed to date at Oskarshamn. It should also be noted that small well in this application, but, because of difficulties experienced in amounts of 2205 stainless steel have been used in the past. This welding titanium, 254 SMO stainless has been the replacement material is no longer used because of the problems experienced with material of choice for heat exchangers since 1984. The replacement crevice corrosion in some of the flanges. of aluminum brass heat exchanger tubes and tubesheets is an ongoing program. Und rgrovrnd anmd lui-Plcrn Piping Cond ensers

Since the service water enters the plant through culverts, there is The original condenser tubes installed in Unit I in 1969 and Unit 2 very little underground piping. Submerged pumps for the three units in 1971 were aluminum brass. Due to corrosion problems that pull the water from the culvert into short sections of underground started within two to three years of installation, the condensers were piping to bring it into the plant. The return pipes are submerged Im retubed in 1978 and 1979 with 544,000 m (1.77 million ft) of (3.28 ft) below the water surface to prevent foaming and splashing titanium. The condenser tubesheets in Units I and 2 are carbon steel of the brackish water. The original underground and in-plant piping clad with Type 304 (18Cr-lONi) stainless steel, and, in Unit 3, they (including the emergency service water system piping) were carbon are clad with titanium. The steam side of the outer most titanium steel with a rubber coating on both the outside and inside of the condenser tubes in Units I sand 2 began showing signs of steam pipe. It was installed in the following years: Unit 1, 1969; Unit 2, droplet erosion as early as 1988. This has resulted in tube leakage 1971; and Unit 3, 1982. As the rubber began to age and crack, and plugging of problem tubes. All the Swedish and Finnish power Oskarshamn began to experience corrosion problems severe enough to require pipe replacement. The same corrosion problems exist in plants with titanium condenser tubes have reported similar both the normal and emergency portions of the system. The rubber problems. Frequent inspections of the outer tubes are done. OKG cracking and corrosion problem has been particularly severe in the re-tubed the Unit 2 condenser with a total of 54,000 m (177,120 ft) crevices of flange joints. The corrosion originated almost entirely on of 254 SMO in 1991. Unit 3's original main condenser tubes are the inside of the pipe. titanium and have not had any problems to date. In 1984, Oskarshamn started replacing sections of the underground pipe and the in-plant pipe in Units I and 2. 254 SMO stainless and SYSTEMR INSPECTION AND titanium were selected as replacement materials. No signs of corro- CLEANING sion have been observed in subsequent pipe inspections, and Oskarshamn is pleased with the performance to date. Both materials Routine inspections are conducted by shift personnel as a part of have worked well, but, since they have found 254 SMO stainless to normal plant operation. Water flow rates are monitored in the be much easier to weld, it will be used for all future installations. central control room and by local flow meters in the plant. The 254 SMO stainless has been the primary in-plant piping Shift personnel look for leakage and other potential problems. replacement material. A summary of the 254 SMO stainless piping In addition, the plant has a regularly scheduled maintenance sizes, elbows, fittings and other components installed to date is program which began in 1978 and has not changed significantly shown in Table 3. since its inception. Cleaning and inspection of the system occurs All of the in-plant piping system components are obtainable in during the annual refuelling outage. Whenever the system is shut 254 SMO stainless. down, the system is flushed with "drinking" water, and ferrosulphate is added to any remaining brackish water to prevent deterioration. It should be noted that there is still a great deal of rubber-lined pipe During outages, the culverts are drained and cleaned using high in the plant. Replacement is occurring as necessary, when leaks pressure equipment. appear or when detached sections of the rubber lining adversely affect the water flow rate. Much of the piping is still rubber-lined carbon steel. This is not generally inspected other than for through-wall leaks or for partial Hoft Eicchvmgers detachment of the rubber lining which causes reduced flow through the pipe. If either problem exists, the section is replaced with The original aluminum brass heat exchanger tubes were installed in 254 SMO stainless. The sections which have already been replaced Units I and 2 in 1969 and 1971, respectively. Each of these units with 254 SMO stainless, are inspected visually every five years in has over fifty shell and tube heat exchangers cooled directly by the accordance with the requirements of a 20-year warranty provided by open portion of the service water system. The only closed loop the manufacturer. The inspection is done by Oskarshamn personnel. The aluminum brass seawater cooled heat exchangers in Units I and glass beads, or by using pickling paste or pickling acid. Carbon steel 2 are cleaned and eddy current tested during the annual refueling brushes are not allowed under any circumstances. Even common outage. Since the titanium heat exchanger tubes have performed grade stainless steel brushes are not suggested unless subsequent well, they are cleaned and generally only visually inspected. Unit 3 chemical cleaning of the weld is done. Brushing can potentially has a high pressure water strainer with 3 mm (0.12 in) filter holes cause iron contamination of the surface which may initiate pitting in installed behind the intake pumps to prevent crustaceans from an aggressive chloride environment. entering the system. Because of this, the titanium heat exchangers in Unit 3 are cleaned every five years. Suspended solids are not considered to be a problem in any of the units. Ball cleaning CONCLUSIONS equipment is run continuously to keep the main condenser free of biofouling. %hen the system is stopped, the condenser is flushed and The demanding service water environment that exists at the dried. Extensive testing of the titanium condenser tubes is required Oskarshamn plant led the materials decision makers to use and gain due to the erosion-corrosion problems that have occurred in the outer experience with highly corrosion resistant materials. This large scale, rows of tubes. Eddy current testing of these tubes is done annually. long-term experience with titanium and a 6Mo austenitic stainless The pumps are visually inspected every year. Normally, one out of steel in a highly demanding service water system environment provides valuable assistance to materials decision makers four pumps is replaced with an overhauled unit so that each pump is encountering similar problems. Titanium; the duplex stainless steel, overhauled an average of once every four years. There is no formal 2205; and the 6Mo austenitic stainless steel, 254 SMO, have all been program for inspecting valves, but, if a valve is temporarily removed used as replacement piping materials in the plant. Titanium has from the system because of other repair work, it is inspected. performed well in all applications except the outermost rows of the condenser tubes, but, due to problems associated with welding, Oskarshamn does not plan to use titanium in the future. Crevice FABRI CATU ON corrosion problems with 2205 eliminated it from future consideration. The preferred replacement material since 1984 has Since Oskarshamn currently uses only 254 SMO austenitic stainless been the 6Mo austenitic stainless steel alloy 254 SMO because of its steel, it will be the only material discussed. All the field and shop corrosion resistance, availability, relative ease of fabrication, and fabrication was done by an outside contractor. The welding proce- strength. Although 254 SMO is the only 6Mo austenitic to have been dure used by Oskarshamn was provided by the steel producer, tried, it is assumed that the other alloys in this family would also Avesta Sheffield AB. The following is a brief summary of infor- perform well. Two alloys that are currently being tested, SAF 2507 mation provided. Several welding techniques are suitable: Gas duplex stainless steel and 654 SMO austenitic stainless steel, may be Tungsten Arc Welding (GTAW or TIG); Gas Metal Arc Welding considered for future installations. (GNIAW or MIG); or Shielded Metal Arc Welding (SMAW). The weld pool should be protected from atmospheric oxidation by an The 6Mo austenitic stainless steels are readily available in all the inert gas cover. Preheating, hot spots, and post-weld heating are not common product forms needed in constructing a service water system. recommended and can be detrimental to the material properties. This makes it possible to replace all existing system components to A filler metal with a chemistry equivalent to Alloy 625 is provide maximum system cost effectiveness and efficiency. Since recommended. The Oskarshamn plant used Avesta P- 12 filler metal there are several 6Mo austenitic stainless steel alloy producers from which is produced by Avesta Welding. The interpass temperature of which to choose, materials specifiers can generally select from a the work piece should not exceed 212' F (100C). This welding variety of sources based on the properties and components required, procedure is similar to the procedures recommended by other quality, technical support, service, delivery, and price. producers of 6Mo austenitic stainless steels. Flange joints were used We ackinowledge the assistance of Al r Fredrik Baniekow of OKG instead of welding to join dissimilar materials. A&7IEBOLAG lio tas indispensable in this project'S success. AIr Any heat tint should be removed after welding by either grinding Barnek-ow prnwided the infonnation used in this case study and with a fine abrasive, by abrasive blasting with 75-100 micron soda-lime retviewed thefinal case stut'for accuracy.

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0 he material presented in this publication has been prepared for the general information of the reader and should not be used or relied on for specific applications without first securing competent advice. The Nickel Development Institute, its members, staff and consultants do not represent or warrant its suitability for any general or specific use and assume no liability or responsibility of any kind in connection with the information herein.

Reprinted from CHEMICAL ENGINEERING, January 1990, copyright 1990 by McGraw Hill, Inc. with all rights reserved. Additional reprints may be ordered by calling Chemical Engineering Reprint Department (212)512-3607 THE RIGHT METAL FOR HEAT EXCHANGER TUBES

Arthur h. Tuthill,* Tuthill Associates Inc. Attention to this checklist of selection factors will materially W^ When designing a heat exchanger, an engineer first calculates reduce heat-exchanger failures km*the surface area needed to carry the heat load. Next, he or she devel- The impact of each factor is noted ual chlorine and manganese. It also ops the design to meet the standards of without it necessarily being related to includes pH, temperature and scaling the Tubular Exchanger Manufacturers that of other factors. In the tables, the tendency (Table 1). Assn. (TEMA) for heat exchangers, or impact of each factor is rated one of Water cleanliness-Design engi- other codes, and the company's stan- three ways: green means the tubing neers tend to assume that cooling wa- dards. He or she then makes compara- alloy or alloy group has given good ter will be clean. This occurs only if the tive cost estimates, factoring in knowl- performance under the stated condi- right screens and filters have been edge from experience, and selects the tions; yellow designates that the tub- installed and operators have made best tubing metal for the service. ing may give good performance, but sure that they work properly. Debris Most unexpected failures of heat ex- may require a closer study of the con- (such as sticks and stones) and sedi- changers can be traced to a factor that ditions at the site and relationships ment (such as sand and mud) that are had not been fully taken into account with other factors; and red signifies passed through or around the screens when the tube material was selected. In that the material has not performed and filters have been responsible for Tables 1, 2 and 3, these factors are well under the stipulated conditions, many tube failures. arranged according to, respectively, and special precautions are required to Long term, copper-alloy and stain- water quality, the character of opera- achieve good performance. less-steel tubes perform excellently in tion and maintenance, and exchanger clean water (i.e., free of sediment, de- design. Tube materials considered are Water quality bris and fouling organisms). Too often, copper alloys, stainless steels (Types Water quality encompasses: cleanli- however, sediment and debris find 304 and 316), and high alloys (6%molyb- ness, and the content of chloride, dis- their way into exchanger tubes. Corro- denum, superferritics* and titanium). solved oxygen and sulfides, and resid- sion under sediment is common with *Anew family of stainless steels high in chromium content (25-30%). tubes of these two materials. A high "Consultant to the Nickel Development institute, 15 Toronto St, Toronto, Ontario, Canada I

1. Water cleanlinets ; -Sedimfe rn~;:+f :\;;:;j I: \00 I:B iolgical Tuibe Clean Mud Sand0 : 0:f;00 D e~bris \ f\t unts me:\ t alz \ concentration of sand can abrade the CA0::;0~: f| - n ill zh zId -:lEDd X\::n -Si protective film on copper-alloy tubes.t ftia:s :s00:1-l czzEiz~ :7e-ED Such service, therefore, requires a 70- 30 CuNi-2Fe-2Mn alloy in the copper- CA = CO pper* a X SS St in esssteel alloy series, or stainless steel. A lodgment of sticks, stones and shell fragments creates downstream turbulence, which can cause pinholes in copper-alloy tubes. The obvious cure for these problems is to screen the water better. As a safeguard, the newer 85-15 CuNi with 0.5 Cr, C72200 alloy and stainless-steel tubes do well in withstanding the effects of lodgment turbulence. Copper- alloy tubes effectively keep organisms from becoming attached, and are preferred when environmental restric- tions on the use of biocides would require frequent manual cleaning of stainless-steel and higher-alloy tubes. Chlorides- These provide a convenient framework for differentiating the stainless-steel alloys. Type 304 stainless steel resists crevice corrosion at chloride-ion concentrations of less than about 200 ppm, and Type 316 does so at levels up to about 1,000 ppm. (The chloride content of U.S. fresh water is typically less than 50 ppm, for which Type 304 stainless steel is therefore normally adequate.) The 42% molybdenum alloys suffer crevice attack at chloride-ion concentrations from 2,000 to 3,000 ppm. Both 4'/2% molybdenum-alloy and duplex (another new family of stainless steels) tubes have been subjected to sea water (20,000 ppm chloride content) and have undergone substantial crevice corrosion beneath fouling. On the other hand, the 6% molybdenum and superferritic alloys, and titanium have proved resistant to crevice and beneath-sediment corrosion in salt water. Dissolved oxygen and sulfides - Copper-alloy and stainless-steel tubes perform best in water having enough oxygen (about 3-4 ppm) to keep fish alive. These tubes also do well in deaerated water, such as that used in water-flood oil wells. Copper-alloy tubes do not stand up well in severely polluted water in which dissolved oxygen has been consumed in the decay tAll alloys form a protective film in corrosive liquids; on stainless steel, it is chromium oxide; on copper alloy, it is cuprous hydroxychloride. process and sulfides are present. ment in which bacteria thrive, promot- Tubes of higher-alloyed stainless steel Leaving an ing microbiologically induced corro- or titanium have served successfully exchanger full, sion. Corrosion will also take place un- in such water. der sediment. If an exchanger is to be Residual chlorine - Both copper-al- or even only left full for more than 2 or 3 days, loy and stainless-steel tubes have per- water should be pumped through it formed well in water containing up to 2 wet, invites once a day to displace the stagnant ppm residual chlorine, and have failed water. If an exchanger will be down in heavily chlorinated water. Although corrosion for at least a week, it should be drained the usual objective is to keep residual and blown dry. chlorine at about 0.5 ppm at the inlet Cleaning schedule - Heat ex- tubesheet, this level is sometimes ex- ever, copper-alloy and higher-alloyed changers should be periodically ceeded and the residual is normally tubes have fared well in such water. flushed out, opened and brush cleaned, higher at the point of injection. Scaling tendency - Copper-alloy to remove sediment and debris and to Acidity -In aerated water of pH and stainless-steel tubes perform well restore heat transfer capability. Ex- less than about 5, a protective film in both hard (scaling) and soft (nonscal- changers handling water high in bio- does not easily form on copper-alloy ing) water. The Langelier saturation logical foulants or sediment should be tubes, so they corrode and thin rapidly. index* is frequently used to distinguish cleaned weekly. Micro-organisms will In deaerated water of low pH, copper- scale-forming from corrosive (to carbon corrode stainless steel if they and oth- alloy tubes resist corrosion well. For steel) water. er deposits are not removed. high-pH water, copper-nickel or stain- Monthly or even quarterly mechan- less-steel tubes are preferred to admi- Operation and maintenance ical cleanings of copper-alloy and ralty- (71% copper, 28% brass, 1%tin) Among these factors are type of oper- stainless-steel tubes are adequate or aluminum-brass tubes, which tend ation (regular vs. intermittent) and the with most waters. The optimum in- to corrode under highly alkaline condi- frequency of cleaning (Table 2). terval can be critical because the protective film on copper alloy tubes can be damaged by cleaning with metallic brushes and some types of abrasive blasting. Mechanical cleaning is sometimes put off for a year, and even longer, particularly if restoring an exchanger's heat-transfer rate is not critical to plant performance. Be cautioned, however, that corrosion beneath sediment frequently occurs when sediment removal is delayed by more than three months. Exchanger design The principal design factors that influence tube performance are water velocity, tube diameter, shape (i.e., once-through or U-bend), orientation, venting, tubesheet material, channel (waterbox) material and channel inlet tions. Stainless-steel tubes have per- Character of operation- Lengthy arrangement (Table 3). formed well at a pH less than 5 and startups have been responsible for Fluid velocity - At velocities of greater than 9. many failures of copper-alloy and less than 3 ft/s, sediment deposit, de- Temperature-A protective film stainless-steel tubes. These occurred bris buildup and biological fouling in readily forms on copper alloys in warm because water had been left in, or it and on tubes can be excessive, result- water (inabout ten minutes at 60TF), but had only been partially drained from, ing in the need for frequent mechani- forms very slowly in cold water. It de- tubes for a long time. Such failures cal cleaning, which can cause copper- velops almost instantaneously on stain- have also been caused by extended alloy and stainless-tube tubes to fail less steel in both warm and cold water. outages from normal operations. prematurely. Manganese - Type 304 stainless steel Leaving an exchanger full, or even Copper alloys can be conveniently tubes have failed in fresh water having an only wet, invites corrosion. The water differentiated according to their wa- appreciable manganese content. How- will become foul, creating an environ- ter-velocity tolerance. Approximate 'This index indicates the tendency of a water solution to precipitate or dissolve calcium carbonate. It is calculated from total maximum design velocities for tubes dissolved solids, calcium concentration, total alkalinity, pH and solution temperature. of copper-base alloys and stainless steel in salt water are listed in Table 3. Maximum velocity is usually arrived at as a compromise between the cost of pumping and the advantage in heat transfer. The design velocity usually falls in the range of 6-8 ft/s, and may reach 12-15 ft/s when extra cooling demand is placed on an exchanger, such as in summer. Copper-nickel tubes stand up reason- ably well to variations in velocity, although some erosion and corrosion may occur at the inlet. The C72200 alloy resists inlet-end erosion and corrosion, as well as corrosion downstream of lodgments. The 2Fe-2Mn modification of the C71500 alloy resists inlet erosion and corrosion excellently. Copper-nickel tubes, after their protective film has aged, withstand considerable velocity excursions without significant inlet erosion. Stainless-steel tubes perform best at high velocity and are useful up to velocities that induce cativation. Cop- per will tolerate somewhat higher velocities in fresh water, 10 ft/s being a common design velocity for copper tubes in air-conditioning condensers cooled with fresh water. Tube diameter - Tubes of large diameter are preferred for heat exchangers because any solids that pass through screens will also flow through the tubes. By one rule of thumb, tube diameters should be at least twice the diameters of the screen openings. Tubes should not be less than Y2 inch if the water to the exchanger is not filtered. Once-through or U-bend - Be- cause U-tube bundles are difficult to clean, the water must be very clean (e.g., boiler feedwater quality), or at least well-filtered. Both stainless- steel and copper-alloy tubes are liable to corrode beneath sediment. U-tubes are particularly prone to such corrosion if sediment and debris are not removed from their bends. Once- through and 2- to 4-pass bundles are easily cleaned by flushing, water lanc- ing, or brushing. Orientation- Heat exchangers, particularly condensers, are normally placed horizontally, with water flowing through the tubes. Both stainless- steel and copper-alloy tubes perform well in such exchangers. In those unusual circumstances that require that the cooling-water flow on the shell- Tubesheet material-Tubesheets have occasionally caused the corro- side of a horizontal exchanger, sedi- of carbon steel, common copper alloy, sion failure of copper-alloy and stain- ment and debris cannot be kept from Muntz metal (a brass composed of 58- less-steel tubes. Coatings applied to building up around the support plates 61% copper, up to 1% lead, with the steel and cast-iron channels for the and lower tubes. This results in corro- remainder zinc), admiralty brass and purpose of reducing corrosion some- sion beneath the sediment. The build- aluminum bronze are anodic to cop- times deteriorate and spall, leading to up can be eliminated, or at least re- per-alloy tubes. The galvanic protec- tube corrosion and failure. Coated strained, by upstream filters, but tion that these tubesheet materials channels are also liable to deep local these will not prevent fouling organ- afford copper-alloy tubes does not corrosion at pinholes in coatings isms from thriving in low-flow areas. eliminate all inlet-end corrosion, but brought on by an adverse galvanic When the water, even clean water, often does help to keep it at a tolera- couple between the steel channel and must be on the shellside, the tubes ble level. the alloy tube and tubesheet. should be of high alloy. Stainless-steel tubesheets are rarely Copper-nickel and aluminum- A condenser is sometimes oriented used with copper-alloy tubes, because bronze (solid or weld-overlaid surface) vertically, with the cooling water on stainless steel is cathodic to copper channels are preferred with copper- the shellside, to improve heat trans- alloy. Installing stainless-steel or tita- alloy tubes, and may also be used with fer. This allows noncondensable gas- nium tubes in copper-alloy tubesheets high-alloy tubes. The adverse galvan- es to collect under the top tubesheet, has accelerated the corrosion of the ic effect is diminished in such installations, because the area of the channel is larger than that of the tubesheet, and the channel and tubes are not TEMA stC3ndards contiguous. Channels of Type 316 stainless steel (solid or overlaid) are recommend tt at exchangers preferred with stainless-steel tubes. be installe CI level, but Channel inlet arrangement- Un- ar even flow, restricted water passages they should really be sloped and poor inlet-piping entry arrangements have caused numerous failures of copper-alloy tubes, as well as a few letting the temperature of the tube tubesheets. Stainless steel and titani- failures of stainless-steel tubes. Basi- walls in the gas pocket get almost as um polarize so readily that the entire cally, the entry and flow pattern in both hot as the incoming gas being con- inside surface of the tubes (not just the large and small channels should distrib- densed, evaporating the water and de- part adjacent to the tubesheet) must ute the water uniformly to all tubes positing scale on the hot tube sur- be considered as the cathode to the with as little swirling as possible. faces. Sediment also tends to build up copper-alloy tubesheet anode. If a review of the foregoing factors in the bottom of a vertical condenser. The normal cure for this anode- indicates that an exchanger's tubes In vertical installations, both Type cathode problem is to protect the cop- must be of a metal that is even more 304 and Type 316 stainless-steel tubes per-alloy tubesheet with an im- corrosion resistant than a copper alloy are prone to stress corrosion and pressed-current cathodic protection or stainless steel, an engineer fre- cracking just under the top tubesheet. unit. The unit's potential must be con- quently resorts to a more highly al- Remedies include: venting gas trolled to avoid hydrogen embrittle- loyed metal, such a 6-molybdenum through the top tubesheet; changing ment of ferritic stainless steel, or by- stainless steel, a superferritic or titani- to copper-alloy or copper alloy-stain- driding of titanium. An alternative is um. These materials provide outstand- less steel bimetallic tubing or to high- to resort to tubes of 6-molybdenum, ing resistance to corrosion in crevices alloy tubing, or orienting the ex- which resist hydrogen embrittlement and beneath sediment. a changer horizontally. Although the without the need to carefully control TEMA standards recommend that ex- an applied potential. The author changers be installed level, exchang- Tubesheets for austenitic stainless Arthur H. Tuthill, a materials and corrosion consultant (2903 ers should really be sloped slightly so steel should be of identical composi- Wakefield Dr., Blackburg, VA that they will drain completely when tion. Tubesheets of high-alloy austen- 24060; tel.: 703-953-2626), has had extensive experience in the shut down, avoiding corrosion where itic stainless steel are used with tubes fabrication, use and perfor- tubes sag between support plates and of ferritic stainless steel, because tu- mance of metals, particularly retain water even after being drained. besheets of matching composition are involving heat exchangers, pip- Venting - Exchangers are normal- not available. Solid or clad titanium ing and pumps, in a vde rane in metallurgical engineering from Carnegie-Mel- ly fitted with vent cocks so they can tubesheets are preferred with titani- lon University and a B.S. in chemical engineering be purged to clear gas pockets. Con- um tubes. from the University of Virginia, he is a licensed engineer (metallurgy). Among the many articles densers, particularly when chlorine is Channel material- Corrosion that he has had published is a five-part series in Chemical Engineerin: "Installed Cost of Corro- used as a biocide, tend to suffer corro- products from bare-steel and cast-iron sion-Resistant Piping (Mar. 3 and 31, Apr. 28, May sion when gases are not vented. channels (exchanger inlet chambers) 26 and June 23, 1986). I - a

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a -e a 4 - - e -- - - - I- a- ** The material presented in this publication has been prepared for the general information of the reader and should not be used or relied on for specific applications without first securing competent advice. The Nickel Development Institute, its members, staff and consultants do not represent or warrant its suitability for any general or specific use and assume no liability or responsibility of any kind in connection with the information herein. Specifying STAINLESS STEEL Surface Treatments Though stainless steel is naturally ing shop dirt, iron particles from cutting tools, and machining lubricants. Passivation treat- passivated by exposure to air and ments of stainless steel with nitric or mild or- other oxidizers, additionalsurface ganic acids are useful mild cleaning operations performed after machining to enhance the treatments often are needed to protective nature of the natural, air-formed film. prevent corrosion. Nitric acid treatment enhances the level of chromium in the protective film on stainless steels.2 DeBold has published an excellent practical Arthur H. Tuthill*, review of nitric acid passivation of stainless steel 3 Blacksbtirg, Va., machined parts. ASTM A 380 describes eight nitric-acid-based Richard E. Avery*, cleaning/passivation treatments and four clean- Londonderry, N.H., ing treatments using other chemicals. None of Consltants to Nickel Development Institute these passivation treatments corrode or etch the surface. Several are designed to clean bright or polished surfaces by removing loosely adherent assivation, pickling, electropolishing, foreign matter. The most common treatment is and in some circumstances, mechanical cleaning, are important surface treatments for the successful performance of Handle with care stainless steel used for piping, pressure vessels, Most surface defects on stainless steel that are tanks, and machined parts in a wide variety of difficult to remove and, thus, contribute to cor- applications. Among them: pulp mills, nuclear rosion, are produced during fabrication. Com- power plants, hospital sterilization systems, food mon defects include embedded steel particles, processing equipment, biotechnology processing heat tint, arc strikes, weld spatter, grind marks, plants, breweries, electronic-chip washing scratches, and organic contamination from facilities, swimming-pool hardware, water treat- marking crayons and paint. All of these tend to ment plants, and chemical process plants. initiate corrosion that would not occur in their Determining which treatment should be used absence, and will accelerate localized corrosion for specific applications is confusing to many in aggressive environments. specifiers. A good place to start is with ASTM A Embedded iron: The surface of stainless steel 380-88, "Cleaning and Descaling Stainless Steel will pick up particles of carbon steel from steel Parts, Equipment and Systems,"' an excellent layout and cutting tables, forming rolls, carbon resource document for the cleaning of stainless steel wire brushes, sandblasting, grinding, and steel, although it does not cover electropolishing. from handling with steel slings and clamps. Sheet and plate should be stored in vertical racks Passivation treatments to avoid scoring that can take place with floor Exposure to air is the natural, primary pas- storage. sivation treatment for stainless steel. This ex- Steel particles embedded in the surface of posure produces a thin, durable chromium- stainless steel will rust when they are exposed to oxide film that forms rapidly on the alloy surface water or a moist atmosphere, showing up as and gives stainless steel its characteristic "stain- spots and streaks which, if not removed, can less" quality. Exposure of the surface to water or produce pitting. other oxidizing environments also produces this Heat tint: Welding heats the base metal, caus- passivating film. ing heavy oxide films (scale) to develop in the Additional passivation is called for in many heat-affected zone (HAZ). These oxide films specifications to remove light surface contamina- range in color from light brown to black. tion from machined stainless steel parts, includ- Removing heat tint is costly, and may be un- Member ofASM International

1 immersion in a 20 to 40% solution of HNO3 at a temperature of 50 to 60'C (120 to 140'F). The complete passivation treatment includes degreasing, immersion, and rinsing. Degreasing, preferably in a nonchlorinated solvent, removes organic contaminants from the surface. Degreasing: Neither air nor nitric acid can form or enhance the protective film when grease, oil, fingerprints, or other organic contamination are present on the surface. Parts must be thoroughly degreased prior to any passivation treatment. The water-break test, described in ASTM A 380, is easy to apply and is effective in detecting residual organic matter that may not have been removed in the degreasing operation. A sheet of water directed over the surface will "break" around oil, grease, and other organic Rust in the heat-affected zone of this weld on a stainless steel pipe (dark contaminants not completely removed from the bands on both sides of the weld) was produced by iron embedded in the sur- surface. Specifications can simply call for no face during wire brushing. Rust spots awayfrom the weld were caused by break in the film as it drains from the vertical particlesfroman overhead sandblastingoperation thatfell on the pipe. surface. ful. Immersion, neutralization, and rinsing must Immersion: The part is immersed in a pas- follow one another without allowing the surface sivating solution selected from ASTM A 380 to dry between steps. When passivating stainless Table A2.1, Part II or Part III. In addition to the steel sheet material, each sheet must be com- standard HNO3 solution, there are a number of pletely dry before it is stacked to avoid water solution variations appropriate for all grades of marks. 200, 300, and 400 series, maraging, precipitation In addition to the cleaning precautions given hardening and free-machining alloys in various in ASTM A 380, different grades of stainless steel heat treat conditions and surface finishes. should not be mixed in the same passivating Rinsing: Immediate and thorough rinsing in bath as this can initiate corrosion where surfaces clean water of pH 6 to 8 is mandatory, In many come in contact.3 instances neutralization prior to rinsing is help- Although nitric acid does not normally cor-

necessary if stainless steel is exposed only to water, alkaline environments, and other mild industrial atmospheres, which seldom initiate corrosion. However, removal of heat tint may be necessary to prevent corrosion in acidic environments, especially when the base metal has very little extra corrosion resistance. In some mild environments, heat tint removal is necessary to prevent contamination of process fluids. Heat tint must be removed when scrupulous- ly clean surfaces are required to prevent contamination and batch-to-batch carryover of process materials. These applications include evaporators and piping for high-purity and ultrahigh-purity water systems, nuclear piping, pharmaceutical and biological equipment, These common surface defects on stainless steel all electronic-chip washing facilities, and brewery resultfrom mechanical operations that are used tofabri- equipment. cate components. Weld flux: Weld flux, produced by welding with covered electrodes, is difficult to remove small pinpoint surface defects in the protective completely, especially from the sides of the weld film, as does weld spatter. If defects cannot be bead. Wire brushing with stainless steel wire prevented, they should be removed before plac- brushes, abrasive disk and flapper wheel grinding stainless steel into service in aggressive en- ing, and chipping may leave small flux particles vironments. at the side of the bead. These particles are excel- Scratches and paint Deep scratches also in- lent crevice formers, and their complete removal itiate corrosion, as can paint crayon marks, and generally requires pickling or electropolishing. other instruction markings if they are not Arc strikes and spatter Arc strikes produce removed.

2 rode stainless steel, it will corrode surfaces that are significantly altered. Acid cleaning should not be used for carburized and nitrided stainless steel parts nor for improperly heat treated high- carbon/high-chromium martensitic grades that have not been fully hardened.3

Pickling treatments Passivation treatments are not designed to remove heat tint, embedded iron particles, heat treating scale, and other surface defects produced during fabrication, since nitric acid does not corrode or remove the surface layers having embedded defects. Elimination of these defects requires removal of the normal, protective oxide layer and 25 to 40 pm (0.001 to 0.0015 in.) of the substrate metal by pickling the surface in a nitric-hydrofluoric acid (HNO,-HF) bath. The protective film then reforms in air over the freshly cleaned surface. This oxide film is uniform and leaves the stainless surface in its normal passive condition. While pickling is not strictly a passivating treatment, it provides many of the same benefits. Pickling is most useful for localized cleaning of welded areas, but also can be used to improve the corrosion resistance of mechanically cleaned surfaces. Disposal of pickle liquor is a growing problem that tends to limit pickling by immersion to those fabricators and chemical cleaning contractors who already have pickle tanks and ap- proved arrangements for disposal. Pickling at the steel mill removes the oxide scale that forms during annealing. Mill pickling also removes manganese sulfides or other inclu- Crevice corrosion can be initiated by deep scratches, top and by paint sions in the surface and removes surface layers and other markings, such as those made by a marking crayon, bottom. Removal of the markings would have prevented the corrosion. that may have been depleted in chromium during annealing. ASTM A 380 lists three pickling solutions for stainless steel. Fabricated austenitic stainless steels can be pickled by immersion in a standard 10% HNO3 , 2% HF bath at 50'C (120TF). For local area pickling or if the fabricated component is too large to be immersed, commercial HNO 3 -HF pickle pastes can be just as effective. Pickle paste can be applied with a paint roller or nylon brush. Paste must be washed off within 15 to 30 min of application, or corrosion will be initiated. Per- sonnel need protective clothing and training in safe handling procedures. Although post-fabrication pickling improves the performance of stainless steels in a variety of applications, until recently there has been very little research data to support field experience. Quantitative data on the increase in critical pitting temperature in ferric chloride (ASTM G 48) shows that pickling provides a 2.5 to 10'C (4.5 to 18TF) improvement in performance.' While not The heat-affected zone on the opposite side of a weld large, the improvements in lightly ground, and can also initiate corrosion f the heavy oxidefilm (scale) glass-bead blasted surfaces are uniformly posi- is not removed. Forexample, the corrosion shown here is tive, indicating that pickling provides benefits on the inside of a vessel, in the heat affected zone of an beyond those obtained with the best controlled external weld. mechanical treatments. 3 p

4, 65 5

Original surface Pickled Ground GroundI Pickled with Glass-bead Glass-bead (IlNOYHF) (60 grit) and pickl ed commercial blasted blasted paste and pickled Base metal - 6%,f,Mo stainless steel Cronifer 1925hNfo (Krupp-VDNI AG)

Pickling of stainless steel increases the critical pitting temperatire in ferric chloride (per ASTM G 48) in the base metal, heat-affected zone, and weld areas. Mechanical cleaning treatnents that are performed without a succeeding pickling treatment decrease tire critical pitting teiperatire. Pickling removes Electrocleaning and electropolishing Electrocleaning, an electropolishing techni- Electrolyte heat tint que, is a useful alternative to pickling treat- Copper Cathode and ments. Although electrocleaning is not covered Insulated embedded under ASTM A 380, it is widely used to remove \,~lp ;. f,...^Z handle Nylon sponge ; .- . h n dl imperfections from the surface of stainless steel siurface after fabrication. It removes embedded iron par- Stainles te Co i- ticles and similar film defects as does pickling. Unlike pickling, electrocleaning does not rough- taininants. Direct-current en the surface, but makes it smoother. A 12-Vdc Anode power source power source with variable current capability is connected to the stainless steel, making it the Localized electrocleaning of heat titfromi the surface anode. A copper cathode and an electrolyte - of stainless steel can be performed with a simple tool usually phosphoric acid - are then used to cor- such as the one shown here. rode away the protective film and several layers Electropolishing, because it uses milder acids of the surface in a controlled manner by varying and can be performed locally, reduces the vol- the current and dwell time. ume of waste liquor for disposal compared with Electrocleaning can be performed in most immersion pickling. However, personnel must plating shops by immersion. Localized electro- be protected and disposal regulations must be cleaning with field kits is widely practiced to re- observed, as is done in other pickling, passi- move heat tint and weld-related defects from the vating, and electrocleaning operations. heat-affected zone. Since both pickling and electropolishing re- Electropolishing is the same process as elec- move metal, neither process can be used on trocleaning, but is generally performed for a polished surfaces without altering the surface longer time. It is used to polish large surfaces. finish. Care should also be used when pickling One use is the polishing of pulp mill headboxes or electropolishing machined surfaces. Although to prevent pulp hang-up on tiny surface imper- only about 25 gm (0.001 in.) of the surface is cor- fections. It is also used in the electronics and roded away, this may be enough to alter toler- biotechnology industries to clean and smooth ances on some closely dimensioned parts. the inside surfaces of pipe and tubing. Large nuclear power plant components also are elec- Mechanical cleaning tropolished to refurbish contaminated surfaces. Section 5.3 of ASTM A 380 describes mechani-

4 cal descaling methods commonly used to clean smeared surface that has microcracks, laps, welds. These include abrasive blasting, brushing, seams, and other sites that can initiate crevice Mechanical grinding, and chipping. However, if these corrosion in aggressive environments. Heavy cleaning mechanical cleaning procedures are not per- grinding with grinding wheels overheats the formed carefully, they can do more harm than surface of stainless steel and degrades its cor- procedures good. rosion resistance to depths greater than the 25 to can do Grit blasting can be extremely detrimental as 50 gm (0.001 to 0.002 in.). As a result, grinding more it is almost impossible to prevent particles of grit should be used only when removal of the weld harm from becoming embedded in the surface being reinforcement (weld crown) is more important than good. blasted. Grit blasting also roughens the surface than optimizing corrosion resistance. to the point where crevice corrosion becomes Chipping is normally used between weld likely. Peening with clean stainless steel shot, passes to remove weld slag, and subsequent which produces compressive stresses in the sur- weld passes normally eliminate any damaging face, reduces the risk of stress corrosion cracking effects. in some applications. However, this must be balanced against the increased risk of crevice Inspection procedures corrosion due to the roughened surface. Several methods of evaluating cleanliness Sand blasting should be avoided unless no after fabrication are described in ASTM A 380. other cleaning method can be used. This is often The water-break test described previously is the case when cleaning stainless steel tank bot- used to determine whether organic contamina- toms that have been inadequately protected tion has been removed from the surface. Water from contamination during construction. Only also is useful in detecting iron contamination: new, uncontaminated sand should be used, and rust streaks and spots will form on wetted sur- then only once. faces over a period of several hours if con- Blasting with clean glass beads is an effective tamination is present. method for local- and large-area cleaning. Clean The copper sulfate and ferroxyl tests are much walnut shells also are a useful blasting medium. more sensitive than the water test, and are Grinding with clean aluminum oxide disks or specified when the surface must be entirely free clean flapper wheels can be used to remove heat of iron. Special considerations apply when test- tint and other weld-related defects. However, ing equipment intended for use with food, even light grinding leaves a cold worked, beverages, or other products for human consumption. The ferroxyl test is effective and easy to use, although the solution does not have a long shelf life. U

For more information: Contact Mr. Arthur H. Tuthill, P.E., at Tuthill Associates Inc., P.O. Box 204, Blacks- burg, VA 24060 (tel: 703/953-2626; fax: 703/953-2636), or Mr. Richard E. Avery at Avery Consulting As- sociates Inc., 117 Winterwood Dr., Londonderry, NH 03053 (tel: 603/434-2625; fax: 603/425-2542). Information on stainless steels can be obtained from the Nickel Development Institute, 214 King St. W. Suite 510, Toronto, Ontario, Canada M5H 3S6 (tel: 416/591-7999; fax: 416/591-7987). Copies of ASTM A 380-88 can be ordered from the American Society for Testing and Materials (ASTM), 1916 Race St., Philadelphia, PA 19103-1187 (tel: 215/299-5400; fax: 215/977-9679). References 1. "Cleaning and Descaling Stainless Steel Parts, Equipment and Systems": ASTM A 380-88, American Society for Testing and Materials Philadelphia, Pa. 2. "An X-Ray Photo-electron Spectroscopic Study of Surface Treatments of Stainless Steels," by K. Asami and K. Hashimoto: Corrosion Science, Vol. 19, 1979, p. 1007-1017. 3. "Passivation of Stainless Steel Parts," by T. DeBold: TAPPI Journal, January 1988, p. 196-198. 4. Dr. Rockel, Krupp VDM GmbH, private com- munication.

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U. - -- 6 eel The material presented in this publication has been prepared for the general information of the reader and should not be used or relied on for specific applications without first securing competent advice. The Nickel Development Institute, its members, staff and consultants do not represent or warrant its suitability for any general or specific use and assume no liability or responsibility of any kind in connection with the information herein. ing damage from the inside of the pipe. Many expedients have been tried to repair lining damage in piping smaller than 36 in. but none have proved completely successful. Municipal water distribution systems and utility raw water intake systems are characterized by long straight runs of sev- Design, water factors eral hundred feet with 20 feet or more between joints or welds. Shipboard, chemical plant and nuclear service water piping systems are characterized by short affect service -water runs, frequent bends and numerous valves * and fittings. It is difficult to maintain the integrity of piping materials any lining in fabricating and erecting a -complex piping system of any diameter. Alloy piping has an inherent technical advantage over lined or coated steel for any complex piping system. The effects of design, water quality, and water The economics favor alloy piping over composition factors on the performance of alloy carbon steel for complex piping systems and carbon steel nuclear piping are reviewed (see Table 2), since labor to fabricate and install is 80-90% of the final cost. The high proportion of labor in the overall - -- - ___ I - cost strongly favors use of the best, not the low-priced, material in complex pip- By Arthur H. Tuthill, PE., Consultant to the given. A "G" rating indicates the piping ing systems. Nickel Development Institute material has given good performance un- Alloy materials are affected somewhat der the indicated condition. "Y" indi- differently by the position of the piping, Cement-lined carbon steel piping is a cates the material may give good perform- Table 3. Horizontal lines that are slightly standard material of construction for water ance depending on site-specific conditions sloped and open vertical lines are easily distribution systems and the principal ma- and the interrelationship with other fac- flushed out and drained completely. SS terial found in most nuclear plant service tors. "R" means the material has not has suffered numerous failures when wa- water piping systems. Cement-lined car- performed well under the indicated condi- ter residues have been left in horizontal bon steel was originally selected, appar- tions and special precautions are required runs that could not be completely drained. ently under the assumption that since it if good performance is to be achieved. CA is somewhat more tolerant of such was standard for municipal water handling Five design factors, three water quality water residues, as is CS. However, both systems it would be the most reasonable factors, and six water composition factors perform best when easily drained. HA is material to use for nuclear service water that have a significant effect on the piping less affected by pipe position. systems. materials are reviewed. Design velocities below 3 fps in fresh Although this selection performed rea- sonably well initially, maintenance in- Design factors Design factors creased as the systems aged and the leak Design factors that influ- rate proved to be greater than could be ence piping performance Table I. Pipe diameter - In. tolerated for nuclear service water piping include (1) size, (2) ar- 6 n. and < 8 n. - 30 in. > 30 n. systems. rangement, (3) orientation, .t yl y 0 Upgrading to alloy piping systems is (4) velocity, and (5) fabri- underway. cation. This report identifies some of the prin- It is difficult to cement- Table 2. Arrangement cipal factors that affect the performance of line or coat small-diameter Straight runs Complex systems cooling water piping. Although several piping. It is even more dif- CS 3 Ft factors are interrelated, each is considered ficult to repair the lining or Alloy G G separately. This allows the engineer to use coating where it has been this report as an engineering checklist to damaged by butt welding Table 3. Orientation ensure that none of the major factors have during pipe fabrication and Horizontal Vertical Level Sloped Open Dead ended been overlooked. There is considerable erection or during inciden- data in the published literature on each of tal maintenance. Alloy pip- C. Y a G y the factors discussed but it has not been ing has an inherent advan- CA Y 3 G Y brought together as in this report. tage over lined or coated SS Y G G YIR In developing this report, carbon steel piping in the smaller diam- HA Be 0 1 G cement-lined piping and other coated steel eters (see Table 1). piping types are assigned the symbol Municipal water distribu- Table 4. Design velocity - FPS (CS); 304L and 316L stainless steels are tion systems and utility raw No flow < 3 3-6 6-9 > 9 represented by (SS); C70600 and C61400 water intake systems where CS Y Y G Y ft by (CA); and 6% Mo and titanium by cement-lined piping per- C70600 A (A a Y (HA). In some sections SS, CA and HA forms well are of large di- materials are grouped under the heading ameter, generally greater ALLOY. than 24 in., and more fre- HA CA( 0 (3 43, The factors that affect their behavior quently 36 to 96 in. where 'C70600 is used rather than CA in this table as not all copper alloys are as are identified and one of three ratings is it is possible to repair lin- tolerant of the higher velocities. or saline waters lead to excessive sedi- more saline waters where 304L would not and fillet welds. ment and debris buildup, biofouling and be considered. Following are some of the 3. Specify smooth root bead with no un- microbiological induced corrosion (MIC) key considerations required to obtain the dercuts, no areas of incomplete penetra- in piping, Table 4. CS is more tolerant of best performance from 316L piping: tion and no excessive buildup of weld low velocity; however, it fouls readily and 1. Procure pipe to ASTM A 312. metal on the I.D. sediment buildup can lead to deterioration 2. Fabricate pipe using matching compo- 4. Specify HN03-HF pickling of fabricat- of the coating. Corrosion failures of SS sition filler metal or higher Mo content ed piping before final assembly in the and under-sediment corrosion of copper filler metal for all butt and fillet welds. field. alloy have occurred in low- and no-flow 3. For butt welds specify smooth root 5. Specify end protectors to prevent entry piping. bead with no undercuts, no areas of in- of dirt during shipment and storage after The normal design velocity for piping complete penetration and no excessive pickling. is about 6 fps and all of these piping buildup of weld metal on the I.D. For titanium: materials perform best at 6 fps. Actually, 4. Specify HNO3-HF pickling of fabricat- 1. Procure pipe to ASTM B 337 Grade. it is the low velocities where sediment can ed piping before final assembly in the 2. Fabricate pipe in a qualified shop using deposit and MIC can occur that must be field. matching composition filler metal for all guarded against. Generally, pipe design 5. Specify end protectors to prevent entry butt and fillet welds. velocities are well within the upper veloc- of dirt during shipment and storage after 3. Specify smooth root bead with no un- ity limit for these piping materials, al- pickling. dercuts, no areas of incomplete penetra- though there are reports of cavitation fail- A major objective of pickling 316L is tion and no excessive buildup of weld ures where too great a pressure drop has to improve the resistance of the welds to metal on the .D. been taken across a single orifice. SS and microbiological induced corrosion. It is 4. Specify end protectors to prevent entry HA are unaffected by velocities higher quite possible that the use of a higher Mo of dirt during shipment and storage after than normally found in piping systems. content filler metal such as 904L, 625 or pickling. Procurement practice and fabri- 5. Prohibit field welds, except in cability considerations have a major Water quality factors unusual situations when special impact on the suitability of each of - precautions can be taken to avoid these candidate piping systems. Tat)le 5. Cleanliness of water loss of shielding gas caused by out- In CS piping, the cement lining Debris Bifoulhers door breezes. or coating is easly applied to Sediment sticks and musseIs, straight runs prior to pipe fabrica- Clean Mud Sand stones barnac :1es Water quality factors tion and installation. After installa- CS QG Y Y Y R Water quality factors that affect tion, the lining or coating is subject CA Gx Y Y Y Q piping performance are cleanliness to mechanical damage when pumps S a Y G G R of water, start-up/standby, and and valves are removed for repair HA G 0 G G R schedule for mechanical cleaning. or replacement and when the sys- Tat ble 6. Startup/standby Design engineers tend to assume tem is opened and cleaned. The Time left full or in wet standby cooling waters are clean, a condi- lining is also subject to damage < 3days 4-7days > WIeek tion that exists only occasionally. when, for example, a gusset might CS OG G Y In a few installations where special be welded on to the outside to CA x G ~ ~ A~~~~Ycare is taken to operate and main- brace the piping and reduce vibra- SS G Y R tain screens and filters diligently, tion. HA (G 0 3 plants have been able to maintain The fact that so many cement- relatively clean cooling water with lined carbon steel piping systems Tat)le 7. Schedule for mechanical cleaning considerable benefits in reducing have been installed in nuclear ser- Scheduled cleaning Interval cooling water system maintenance. monthly/quarterly Yee vice water piping systems indicates - ily More often debris, (sticks, stones that most of the problems can be CS G and shells) and sediment (sand and overcome. That these apparently CA X G FR mud) succeed in bypassing the sev- properly installed carbon steel pip- SS G eral screening stations. ing systems must now be upgraded HA 0G Debris and sediment are respon- differentiates the more stringent re- sible for many of the problems the quirements that nuclear service water pip- C22 would also improve the resistance of nuclear industry has encountered with ser- ing systems must meet. welds in 316L to MIC. With a higher vice water piping. The difference in be- In CA systems copper nickel piping is alloy filler metal the base metal should havior of piping materials in clean and routinely fabricated into the complex pip- tend to protect the weld metal galvanical- more typical cooling waters is not fully ing systems found in the engine rooms of ly, reducing the possibility of MIC attack appreciated and frequently neglected in naval and merchant ships. Fabrication is on welds. The evaluations of the resist- the piping materials selection process. not a limitation for CA provided brazing ance to stagnant water conditions and All piping materials perform best in the is limited to 2 in. and smaller diameters. MIC now underway should help clarify clean waters designers assume will be In SS systems Type 304L piping is the usefulness of such galvanic protection used (See Table 5). Under-sediment cor- purchased to ASTM A 312 and fabricated of the weld metal and of HN03-HF pick- rosion is a common cause of corrosion of to user requirements. Fabrication is not a ling in improving the resistance of type stainless steel and copper alloy piping. limitation for type 304L in fresh water 316L to MIC and stagnant water corro- The coatings used to protect carbon steel service. However, other considerations, sion. piping also suffer progressive damage and the minimal differences in installed For HA systems, following are some of from sediment and debris. Debris can be cost as compared to type 316L piping, the key requirements needed to obtain eliminated by improved screens and tend to limit the use of type 304L piping. good performance from 6% Mo piping: strainers. Sediment can be reduced by Type 316L piping is also purchased to 1. Procure pipe to ASTM A 312 better piping arrangements, especially at ASTM A 312 and fabricated to user re- (S31254), B 675 (N08637) or B 673 the intake. HA is quite resistant to debris quirements. However, welding and post- (N08925). and sediment. welding cleanup is critical to success with 2. Fabricate pipe using higher Mo content Biofouling is the most difficult factor to 316L. Type 316L tends to be used in the filler metal, alloy 625 or C22, for all butt control. Copper nickel's inherent resist-

2 type are easily prevented work for differentiating the individual Water composition factors by keeping the water circu- stainless alloys. See Table 8. Type 304 is Table 8. Chlorides lating for short shutdowns resistant to crevice corrosion below about and by draining for longer 200 ppm. Crevice corrosion of type 304/ Chlorides in ppm < 200 < 1000 > 1000 Sea water shutdowns. Nevertheless, 304L in fresh waters, which are generally - ~-~-~---~failures still continue to be in the range of 20-100 ppm chlorides, is Cs a, Q --0_ reported. rarely reported. Type 316 is resistant be- 0 Leaving units full, par- low about 1000 ppm. Performance of CS 304 tially drained or simply wet and CA piping is not significantly affected invites stagnant water cor- by chloride ion concentration. HA (6% Os 0 s rosion. The oxygen in a Mo and titanium) have proven resistant to (3 stagnant system is rapidly crevice corrosion and under-sediment cor- Table 9. Dissolved oxygen/sulfides depleted by corrosion and rosion in saline waters and sea water. Regarding dissolved oxygen/sulfides > 3-4 ppm 02 Demerated SUMfde pollution by biological oxygen demand, i.e., decay of micro (see Table 9), copper alloy piping per- Y, and macro organic matter forms best in natural waters with suffi- CA A found in nearly all waters. cient oxygen for fish to live, about 3-4 (3 Organisms die and stagnant ppm. Both copper alloy and stainless steel HA 0( waters rapidly become also perform well in deaerated waters, -GATable 10. Chlorine0 residual A foul. Bacteria thrive, creat- such as those used in water flooding oper- < 2 ppm 2-10ppm > ing local environments that ations in oilfields and in desalination favor microbiological in- plants. Copper alloys do not perform well duced corrosion (MIC). in severely polluted waters where dis- Sediments deposit, inviting solved oxygen has been consumed in the fl under-sediment corrosion. decay processes and sulfides are present.

HA ( _ 9! The remedy is simply good In such waters SS and HA are resistant Table 11. pH ri housekeeping. and preferred. CS is less affected by sul- If units are to be left full fide pollution than copper alloy. Normal 6-8 <5 , for more than 2-3 days, All classes of piping materials have 0, pumps should be cut on performed well in waters with up to about CA G Y once a day to displace the 2 ppm residual chlorine (see Table 10), 0 foul stagnant water with which is the maximum the piping is likely HA _ G fresh water. If the units are to encounter except in the vicinity of the Table 12. Temperature to be down for more than a point of injection and under unusual con- 324rF 60F 5 120F -140F week, they should be fully ditions of over-chlorination. Heat ex- drained and blown dry. CS changer and condenser tubing of both Cs a (a Y is less affected than the al- classes of material have failed in waters CA V G loy materials, but requires that were heavily over-chlorinated. Nor- 0 similar attention for best mal good practice is to aim at about 0.2 to HA _ G _ performance. HA is resist- 0.5 ppm residual chlorine at the inlet tube Table 13. Manganese ant to considerably more sheet and near zero at the outfall. Higher residuals may occur due to foul waters, Present Absent abuse but good housekeeping should still be main- poor control of chlorination, or over-chlo- CS G tained. rination as in some Mideast desalination CA V Piping systems are fre- plants. SS R 0 quently flushed out when Since stainless steels and HA as well as HA G Oft, heat exchangers are opened CS are dependent upon chlorination or and mechanically cleaned. other biocide treatments for control of ance to biofouling is a major reason for its As long as these cleanings are done at biofouling, a number of programs have use in piping on naval and merchant ves- reasonable intervals little difficulty from been instituted to study the effect of resid- sels. While the resistance is not complete, sediment and deposits is reported. It is ual chlorine on the corrosion behavior of it is adequate to permit ship operation for when sediment is allowed to build up over SS and HA. These studies are far from a month or more between flush cleanings extended periods that under-sediment cor- complete, but have shown that the effect in port. None of the other piping materials rosion becomes a problem in piping (see of chlorine may be quite complex. Chlo- have any resistance to the growth of the Table 7). rine impacts the nature of the slime layer biofouling organisms present in most Both copper alloys and stainless steels and of the bacteria colonies, both of cooling waters. Flow has been, reduced perform best in these relatively clean wa- which can affect the behavior of stainless and blocked in some smaller diameter ters where monthly or quarterly mechani- steel. Chlorine also has a direct effect on lines by biofouling growth; Asiatic clams, cal cleanings are sufficient to keep the the behavior of stainless steel. The net for example. Biofouling must be con- heat exchangers operating at design lev- effect seems to be a considerable increase trolled with biocides such as chlorine in els. CS is somewhat more tolerant of in sensitivity to crevice corrosion. More order to maintain flow capability with CS, extended cleaning intervals. HA is quite information is needed, but normal chlori- SS and HA piping. resistant to such abuse, but good house- nation practice is not expected to greatly The extended start-up periods (see Ta- keeping is still in order. affect the selection of piping materials. ble 6) of modern power plants and the At low pHs, corrosion of carbon steel extended outfitting periods of ships have Water composition factors tends to be rapid where defects in the led to failures of copper alloy and stain- Water composition factors that affect pip- coating expose the substrate steel. At high less steel piping where water has been left ing performance include chlorides, dis- pHs the coatings tend to deteriorate and in, or incompletely drained from, the pip- solved oxygen/sulfides, residual chlorine, spall. At pHs of less than about 5, copper ing after initial wetting or during extended pH, temperature, and manganese. alloys have difficulty in forming a good outages in later operation. Failures of this Chlorides provide a convenient frame- protective film in aerated waters and are 3 subject to rather high general corrosion tems also favors alloy over carbon steel. Titanium also appears to meet the nu- rates and thinning. In deaerated waters of Carbon steel cement-lined or coated is clear industry's need for high reliability low pH, copper alloys have excellent re- most likely to meet nuclear service water piping provided field welds can be avoid- sistance to corrosion. SS and HA have piping reliability requirements in long ed. performed well at pHs less than 5 and straight runs of 36 in. and larger diameters. greater than 9 (see Table 11). Copper nickel piping, although stan- References The protective film forms readily on dard in the complex piping systems char- 1. Tuthill, A.H., "Successful Use of Carbon Steel, Copper Base Alloys, and Stainless Steels copper alloys in warm waters, about 10 acteristic of ships, has met with less suc- in Service Water Systems in Other Industries," minutes at 60 F, but takes much longer at cess in nuclear service, due primarily to Proceedings EPRI Service Water System Reli- the lower temperatures encountered in low flow and under-sediment type corro- ability Improvement Seminar, Charlotte, N.C., arctic waters and in temperate waters dur- sion. Copper nickel may have to be re- October 17-19, 1988. 2. Maurer, J.R. and G.J. Zelinski, "Devel- ing the winter months. The film forms evaluated if increasingly stringent regula- oping a Six Percent Molybdenum Stainless almost instantaneously on SS and HA in tions ban the use of biocides to control Alloy for Extended Service Water Piping Sys- both arctic and tropical waters. The per- biofouling. tem Reliability," Proceedings EPRI Service formance of cement and most coatings There is so little difference in final Water System Reliability Improvement Semi- nar, Charlotte, N.C., October 17-19, 1988. used with CS is not significantly affected installed cost that there appears to be only 3. Tuthill, A.H., "Installed Cost of Corro- by temperatures within these ranges (see a limited role for type 304L piping in sion Resistant Piping," Chemical Engineering, Table 12). some fresh water systems. March 3, 1986, p. 113. Type 304 stainless steel tubing has suf- Type 316L piping has suffered MIC fered failures in fresh waters with appre- and weld metal corrosion in nuclear ser- THE AUTHOR ciable manganese present (see Table 13). vice water piping. Pickling in HNO3-HF Copper alloy and higher alloyed tubing and the use of more highly alloyed weld Arthur Tuthill is a are less affected, although there are re- metal may increase the resistance of type consultant to the ports of corrosion of copper nickel in 316L piping to the point where it will be Nickel Develop- some waters with high manganese con- resistant to MIC and low flow conditions o. ment Institute. He tent. in nuclear service water piping systems. holds a BS degree Evaluations now underway should clarify in chemical engi- Summary the usefulness of properly fabricated and neering from the Alloy piping, not lined or coated carbon University of Vir- pickled Type 316L piping. ginia and an MS steel, must be rated the material of choice 6% Mo alloy piping is the material degree In metallur- for nuclear service water piping systems most likely to met the nuclear industry's gical engineering from Carnegie Insti- of less than 36 in. in diameter. The com- need for highly reliable service water pip- tute of Technology. He is a registered plexity of most nuclear water piping sys- ing. professional engineer in Louisiana. 3-~ - ~ ~ , ;-i~ S.

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i".1 I CONTENTS Introduction ...... 1 Identification of Stainless Steel ...... 1 Guidelines for Selection ...... 5 Corrosion Resistance ...... 5 Material Selection ...... 5 Mechanical & Physical Properties ...... 9 Austenitic ...... 9 Ferritic ...... 9 Martensitic ...... 11 Precipitation Hardening ...... 12 High-Temperature Mechanical Properties ...... 14 Thermal Stability ...... 14 Low-Temperature Mechanical Properties ...... 16 Heat Transfer Properties ...... 17 Sizes, Shapes, and Finishes ...... 18 Fabrication ...... 18 Hot Forming ...... 18 Cold Forming ...... 25 Machining ...... 27 Joining ...... 28 Welding ...... 28 Soldering ...... 29 Brazing ...... 29 Fastening ...... 29 Surface Protection & Cleaning ...... 30 Appendix A Corrosion Characteristics ...... 31 Appendix B Figures ...... 35 References ...... 52

The Specialty Steel Industry of North America (SSINA) and the individual companies it represents have made every effort to ensure that the information presented in this handbook is technically correct. However, neither the SSINA nor its member companies warrants the accuracy of the information contained in this handbook or its suitability for any general and specific use, and assumes no liability or responsibility of any kind in connection with the use of this information. The reader is advised that the material contained herein should not be used or relied on for any specific or general applications without first securing competent advice.

5-98-20 INTRODUCTION Stainless steels are iron-base alloys containing 10.5% or more chromium. They have been used for many industrial, architectural, chemical, and consumer applications for over a half century. Currently there are being marketed a number of stainless steels originally recognized by the American Iron and Steel Institute (AISI) as standard alloys. Also commercially available are proprietary stainless steels with special characteristics. (See Appendix A.) With so many stainless steels from which to choose, designers should have a ready source of information on the characteristics and capabilities of these useful alloys. To fill this need, the Committee of Stainless Steel Producers initially prepared this booklet. The data was reviewed and updated by the Specialty Steel Industry of North America (SSINA). Written especially for design engineers, it presents an overview of a broad range of stainless steels - both standard and proprietary - their compositions, their properties, their fabrication, and their use. More detailed information on the standard grades, with special emphasis on the manufacture, finish designations and dimensional and weight tolerances of the product forms in which they are marketed, is contained in the Iron and Steel Society of the AIME (the American Institute of Mining, Metallurgical and Petroleum Engineers) "Steel Products Manual - Stainless and Heat Resisting Steels." The AIME undertook the publication, updating and sale of this manual after the AISI discontinued publication in 1986.

Reference is often made to stainless steel in the singular sense as if it were one material. Actually there are well over 100 stainless steels alloys. Three general classifications are used to identify stainless steels. They are: 1. Metallurgical Structure. 2. The AISI numbering system: namely 200, 300, and 400 Series numbers. 3. The Unified Numbering System, which was developed by American Society for Testing Materials (ASTM) and Society of Automotive Engineers (SAE) to apply to all com- merical metals and alloys. There are also a number of grades known by common names that resemble AISI designations and these are recognized by ASTM. These common names, which are neither trademarks nor closely associated with a single producer, are shown and identified in the tables. These common (non-AISI) names also appear in the ASTM specification. Nearly all stainless steels used in North America have UNS designations. On the following pages there is a description of these classifications. Tables 1-5 list stainless steels according to metallurgical structure: austenitic, ferritic, martensitic, precipitation hardening, and duplex.

/o SPECIALTY STEEL INDUSTRY OF NORTH AMERICA id! ' g | 3050 K Street, N.W. Washington, D.C. 20007 TEL: (202) 342-8630 or (800) 982-0355 FAX: (202) 342-8631 http://www.ssina.com 1 Austenitic stainless steels (Table 1) Ferritic stainless steels (Table 2) are Precipitation-hardening stainless containing chromium and nickel are iden- straight-chromium 400 Series types that steels (Table 4) are chromium-nickel tified as 300 Series types. Alloys contain- cannot be hardened by heat treatment, types, some containing other alloying ele- ing chromium, nickel and manganese are and only moderately hardened by cold ments, such as copper or aluminum. identified as 200 Series types. The stain- working. They are magnetic, have good They can be hardened by solution treat- less steels in the austenitic group have ductility and resistance to corrosion and ing and aging to high strength. different compositions and properties, oxidation. Type 430 is the general- but many common characteristics. They purpose stainless of the ferritic group. can be hardened by cold working, but Table 4 not by heat treatment. In the annealed PRECIPITATION HARDENING condition, all are essentially nonmag- Table 2 STAINLESS STEELS netic, although some may become FERRITIC STAINLESS STEELS slightly magnetic by cold working. They UNS UNS TYPE Equivalent TYPE Equivalent have excellent corrosion resistance, UNS IUNS S13800 S17400 unusually good formability, and increase S15500 S17700 in strength as a result of cold work. 405 S40500 430FSe S43023 Type 304 (sometimes referred to as 409 S40900 434 S43400 18-8 stainless) is the most widely used 429 S42900 436 S43600 Duplex stainless steels (Table 5) have alloy of the austenitic group. It has a nominal composition of 18% chromium 430 S43000 442 S44200 an annealed structure which is typically 430F S43020 446 S44600 about equal parts of austenite and ferrite. and 8% nickel. Although not formally defined, it is generally accepted that the lesser phase will be Martensitic stainless steels (Table 3) at least 30% by volume. Duplex stainless steels offer several Table 1 are straight-chromium 400 Series types AUSTENITIC that are hardenable by heat treatment. advantages over the common austenitic STAINLESS STEELS They are magnetic. They resist corrosion stainless steels. The duplex grades are in mild environments. They have fairly highly resistant to chloride stress corro- Equivalent Equivalent good ductility, and some can be heat sion cracking, have excellent pitting and TYPE UNS TYPE UNS treated to tensile strengths exceeding crevice corrosion resistance and exhibit 201 S20100 310 S31000 200,000 psi (1379 MPa). about twice the yield stength as conven- 202 S20200 310S S31008 Type 410 is the general-purpose alloy of tional grades. Type 329 and 2205 are 205 S20500 314 S31400 the martensitic group. typical alloys. 301 S30100 316 S31600 With respect to the Unified Numbering 302 S30200 316L S31603 Table 3 System, the UNS designations are 302B S30215 316F S31620 MARTENSITIC shown alongside each AISI type number, 303 S30300 316N S31651 STAINLESS STEELS in Tables 1-5, except for four stainless 303Se S30323 317 S31700 steels (see Table 4) for which UNS des- TYPE Equivalent TYPE Equivalent ignations only are listed. 304 S30400 317L S31703 UNS IUNS 304L S30403 317LMN S31726 403 S40300 420F S42020 302H0 S30430 321 S32100 Table 5 410 S41000 422 S42200 DUPLEX 304N S30451 330 N08330 414 S41400 431 S43100 TypetName UNS 305 S30500 347 S34700 416 S41600 440A S44002 308 S30800 348 S34800 416Se S41623 440B S44003 329 S32900 2205 S31803 309 S30900 384 S38400 420 S42000 440C S44004 309S S30908 2205 (hi N) S32205

2 AUSTENITIC

330 Ni added to resist carburization & thermal shock

3 FERRITIC

430 General Purpose

| . . . .~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

405 446 442 429 Lower Cr 409 43 F 434 Cr Cr Slightly At added Lower Cr P & S Mo added increased increased Less Cr to prevent Primarily added for for improved to improve - to improve for better hardening used for improved corrosion scaling scaling weldability when cooled automotive machining resistance resistance resistance from elevated exhaust in auto trim temperatures

430F Se 436 Se added Mo. Cb added for better for corrosion machined & heat surfaces resistance & improved roping

MARTENSITIC

422 Strength & toughness to 1200 F via addition of Mo V. W

Al - Aluminum P - Phosphorus C - Carbon S - Sulfur Cr - Chromium Se - Selenium Cb - Columbium Si - Silicon Co - Cobalt Ta - Tantalum Cu - Copper Ti - Titanium Mn - Manganese V - Vanadium Mo - Molybdenum W - Tungsten N - Nitrogen SCC - Stress - Corrosion Ni - Nickel Cracking

4 GUIDELINES FOR SELECTION Material Selection The above comments on the suitability Stainless steels are engineering Many variables characterize a corro- of stainless steels in various environments materials with good corrosion resistance, sive environment - i.e., chemicals and are based on a long history of successful strength, and fabrication characteristics. their concentration, atmospheric condi- application, but they are intended only as They can readily meet a wide range of tions, temperature, time - so it is difficult guidelines. Small differences in chemical design criteria - load, service life, low to select which alloy to use without know- content and temperature, such as might maintenance, etc. Selecting the proper ing the exact nature of the environment. occur during processing, can affect cor- stainless steel essentially means weigh- However, there are guidelines: rosion rates. The magnitude can be con- ing four elements. In order of importance, Type 304 serves a wide range of appli- siderable, as suggested by Figures 2 and they are: cations. It withstands ordinary rusting in 3. Figure 2 shows small quantities of 1.Corrosion or Heat Resistance - architecture, it is resistant to food- hydrofluoric and sulfuric acids having a the primary reason for specifying stain- processing environments (except possi- serious effect on Type 316 stainless steel less. The specifier needs to know the bly for high-temperature conditions in an environment of 25% phosphoric nature of the environment and the degree involving high acid and chloride con- acid, and Figure 3 shows effects of tem- of corrosion or heat resistance required. tents), it resists organic chemicals, perature on Types 304 and 316 in very 2. Mechanical Properties - with par- dyestuffs, and a wide variety of inorganic concentrated sulfuric acid. ticular emphasis on strength at room, chemicals. Type 304 L (low carbon) Service tests are most reliable in deter- elevated, or low temperature. Generally resists nitric acid well and sulfuric acids at mining optimum material, and ASTM G 4 speaking, the combination of corrosion moderate temperature and concentra- is a recommended practice for carrying resistance and strength is the basis for tions. It is used extensively for storage of out such tests. Tests should cover condi- selection. liquified gases, equipment for use at tions both during operation and shut- 3. Fabrication Operations - and cryogenic temperatures (304N), appli- down. For instance, sulfuric, sulfurous how the product is to be made is a third- ances and other consumer products, and polythionic acid condensates level consideration. This includes forging, kitchen equipment, hospital equipment, formed in some processes during shut- machining, forming, welding, etc. transportation, and waste-water downs may be more corrosive than the 4. Total Cost - in considering total treatment. process stream itself. Tests should be cost, it is appropriate to consider not only Type 316 contains slightly more nickel conducted under the worst operating material and production costs, but the life than Type 304, and 2-30/o molybdenum conditions anticipated. cycle cost including the cost-saving giving it better resistance to corrosion Several standard reference volumes benefits of a maintenance-free product than Type 304, especially in chloride discuss corrosion and corrosion control, having a long life expectancy. environments that tend to cause pitting. including Uhlig's Corrosion Handbook; Type 316 was developed for use in sulfite LaQue and Copsons' Corrosion CORROSION RESISTANCE pulp mills because it resists sulfuric acid Resistance Of Metals and Alloys; Fontana Chromium is the alloying element that compounds. Its use has been broad- and Greens' Corrosion Engineering; A imparts to stainless steels their corrosion- ened, however, to handling many chemi- Guide to Corrosion Resistance by Climax resistance qualities by combining with cals in the process industries. Molybdenum Company; the Corrosion oxygen to form a thin, invisible chromium- Type 317 contains 3-4% molybdenum Data Survey by the National Association oxide protective film on the surface. (higher levels are also available in this of Corrosion Engineers; and the ASM (Figure 1. Figures are shown in Appendix series) and more chromium than Type Metals Handbook. Corrosion data, B.) Because the passive film is such an 316 for even better resistance to pitting specifications, and recommended prac- important factor, there are precautions and crevice corrosion. tices relating to stainless steels are also which must be observed in designing Type 430 has lower alloy content than issued by ASTM. Stainless steels resist stainless steel equipment, in manufactur- Type 304 and is used for highly polished corrosion in a broad range of conditions, ing the equipment, and in operation and trim applications in mild atmospheres. It but they are not immune to every environ- use of the equipment, to avoid destroying is also used in nitric acid and food ment. For example, stainless steels per- or disturbing the film. processing. form poorly in reducing environments, In the event that the protective (passive) Type 410 has the lowest alloy content such as 50% sulfuric and hydrochloric film is disturbed or even destroyed, it will, of the three general-purpose stainless acids at elevated temperatures. The cor- in the presence of oxygen in the environ- steels and is selected for highly stressed rosive attack experienced is a breakdown ment, reform and continue to give maxi- parts needing the combination of of the protective film over the entire metal mum protection. strength and corrosion resistance, such surface. The protective film is stable and protec- as fasteners. Type 410 resists corrosion in Such misapplications of stainless steels tive in normal atmospheric or mild aque- mild atmospheres, steam, and many mild are rare and are usually avoided. The ous environments, but can be improved chemical environments. types of attack which are more likely to by higher chromium, and by molybde- 2205 may have advantages over Type be of concern are pitting, crevice attack, num, nickel, and other alloying elements. 304 and 316 since it is highly resistant to stress corrosion cracking, and intergranu- Chromium improves film stability; chloride stress corrosion cracking and is lar corrosion, which are discussed in molybdenum and chromium increase about twice as strong. Appendix A. resistance to chloride penetration; and nickel improves film resistance in some Table 6 lists the relative corrosion resis- acid environments. tance of the AISI standard numbered stainless steels in seven broad categories of corrosive environments. Table 7 details more specific environments in which various grades are used, such as acids, bases, organics, and pharmaceuticals.

5 Table 6 Relative Corrosion Resistance of AISI Stainless Steels (1)

Mild Atmos- Atmospheric Chemical TYPE UNS pheric and Number Number Fresh Water Industrial Marine Mild Oxidizing Reducing

201 (S20100) x 202 (S20200) x 205 (S20500) x 301 (S30100) x 302 (S30200) x 302B (S30215) x 303 (S30300) 303 Se (S30323) 304 (S30400) 304L (S30403) (S30430) 304N (S30451) 305 (S30500) 308 (S30800) 309 (S30900) 309S (S30908) 310 (S31000) 310S (S31008) 314 (S31400) 316 (S31600) xX 316F (S31620) 316L (S31603) S 316N (S31651) S 317 (S31700) S 317L (S31703) 321 (S32100) 329 (S32900) x 330 (No8330) S 347 (S34700) 348 (S34800) 384 (S38400) 403 (S40300) 405 (S40500) 409 (S40900) 410 (S41000) 414 (S41400) 416 (S41600) 416 Se (S41623) 420 (S42000) 420F (S42020) 422 (S42200) 429 (S42900) x 430 (S43000) S 430F (S43020) 430F Se (S43023) 431 (S43100) 434 (S43400) S 436 (S43600) x 440A (S44002) 440B (S44003) 440C (S44004) 442 (S44200) S 446 (S44600) S (S13800) S (S15500) x (S17400) S (S17700) S

' The "X" notations indicate that a specific stainless steel type may be considered as panies. When selecting a stainless steel foranycorrosive environment, it is always best resistant to the corrosive environment categories. to consult with a corrosion engineer and, if possible, conduct tests in the environment involved under actual operating conditions. This list is suggested as a guideline only and does not suggest or imply a warranty on the part of the Specialty Steel Industry of the United States or any of the member com-

6 Table 7 Where Different Grades Are Used (15)

Environment I Grades Environment I Grades

Acids used for fractionating equipment, for 30 to 99% Hydrochloric acid Stainless generally is not recommended except concentrations where Type 304 cannot be used, for when solutions are very dilute and at room storage vessels, pumps and process equipment temperature. handling glacial acetic acid, which would be dis- colored by Type 304. Type 316 is likewise applicable "Mixed acids" There is usually no appreciable attack on Type 304 for parts having temperatures above 120 F (50 C), or 316 as long as sufficient nitric acid is present. for dilute vapors and high pressures. Type 317 has somewhat greater corrosion resistance than Type Nitric acid Type 304L or 430 is used. 316 under severely corrosive conditions. None of the stainless steels has adequate corrosion resist- Phosphoric acid Type 304 is satisfactory for storing cold phosphoric ance to glacial acetic acid at the boiling tempera- acid up to 85% and for handling concentrations up ture or at superheated vapor temperatures. to 5% in some unit processes of manufacture. Type 316 is more resistant and is generally used for stor- Aldehydes Type 304 is generally satisfactory. ing and manufacture if the fluorine content is not too high. Type 317 is somewhat more resistant than Amines Type 316 is usually preferred to Type 304. Type 316. At concentrations up to 85%, the metal temperature should not exceed 212 F (100 C)with Cellulose acetate Type 304 is satisfactory for low temperatures, but Type 316 and slightly higher with Type 317. Oxidiz- Type 316 or Type 317 is needed for high tempera- ing ions inhibit attack and other inhibitors such as tures. arsenic may be added. Citric, formic and Type 304 is generally acceptable at moderate tem- Sulfuric acid Type 304 can be used at room temperature for con- tartaric acids peratures, but Type 316 is resistant to all concen- centrations over 80%. Type 316 can be used in trations at temperatures up to boiling. contact with sulfuric acid up to 10% at temperatures up to 120 F (50 C)if the solutions are aerated; Esters From the corrosion standpoint, esters are compar- the attack is greater in airfree solutions. Type 317 able with organic acids. may be used at temperatures as high as 150 F (65 C) with up to 5% concentration. The presence of other Fatty acids Up to about 300 F (150 C),Type 304 is resistant to materials may markedly change the corrosion rate. fats and fatty acids, but Type 316 is needed at 300 As little as 500 to 2000 ppm of cupric ions make it to 500 F (150 to 260 C) and Type 317 at higher possible to use Type 304 in hot solutions of moder- temperatures. ate concentration. Other additives may have the opposite effect. Paint vehicles Type 316 may be needed if exact color and lack of contamination are important. Sulfurous acid Type 304 may be subject to pitting, particularly if some sulfuric acid is present. Type 316 is usable at Phthalic anhydride Type 316 is usually used for reactors, fractionating moderate concentrations and temperatures. columns, traps, baffles, caps and piping. Bases Soaps Type 304 is used for parts such as spray towers, but Ammonium hy- Steels in the 300 series generally have good corro- Type 316 may be preferred for spray nozzles and droxide, sodium sion resistance at virtually all concentrations and flake-drying belts to minimize offcolor product. hydroxide, caustic temperatures in weak bases, such as ammonium solutions hydroxide. In stronger bases, such as sodium hy- Synthetic Type 316 is used for preheat, piping, pumps and droxide, there may be some attack, cracking or detergents reactors in catalytic hydrogenation of fatty acids to etching in more concentrated solutions and at high- give salts of sulfonated high molecular alcohols. er temperatures. Commercial purity caustic solutions may contain chlorides, which will accentuate Tall oil (pulp and Type 304 has only limited usage in tall-oil distilla- any attack and may cause pitting of Type 316 as paper industry) tion service. High-rosin-acid streams can be han- well Type 304. dled by Type 316L with a minimum molybdenum content of 2.75%. Type 316 can also be used in the Organics more corrosive high-fatty-acid streams at tempera- Acetic acid Acetic acid is seldom pure in chemical plants but tures up to 475 (245 C), but Type 317 will probably generally includes numerous and varied minor con- be required at higher temperatures. stituents. Type 304 is used for a wide variety of equipment including stills, base heaters, holding Tar Tar distillation equipment is almost all Type 316 tanks, heat exchangers, pipelines, valves and pumps because coal tar has a high chloride content; Type for concentrations up to 99% at temperatures up to 304 does not have adequate resistance to pitting. about 120 F(50 C). Type 304 is also satisfactory for contact with 100% acetic acid vapors, and-if Urea Type 316L is generally required. small amounts of turbidity or color pickup can be tolerated-for room temperature storage of glacial Pharma- acetic acid. Types 316 and 317 have the broadest ceuticals Type 316 is usually selected for all parts in contact range of usefulness, especially if formic acid is also with the product because of its inherent corrosion present or if solutions are unaerated. Type 316 is resistance and greater assurance of product purity.

7 Table 8 AUSTENITIC STAINLESS STEELS Nominal Mechanical Properties Chemical Analysis %6(Max. unless noted otherwise) (Annealed Sheet unless noted otherwise)

Elon- Hard- Yield gation ness Prod- Tensile Strength in 2 (Rock- uct Strength (0.2% offset) (50.80mm) well) Form Type C Mn P S Si Cr Ni Mo Other ksi MPa ksi MPa %

201 0.15 5 50 7.50 0.060 0.030 1 00 16.00 18.00 3.50 5.50 025N 95 655 45 310 40 B90

202 0.15 7.50 10.00 0.060 0.030 1 00 17.00 19 00 4.00 6 00 0.25N 90 612 45 310 40 B90

205 0.120.25 14.00 15.50 0.030 0.030 0.50 16.50 18 00 1 00 1 75 0.32/0.40N 120.5 831 69 476 58 B98 (Plate)

301 0.15 2.00 0.045 0.030 1 00 16 00 18 00 6 00 8.00 110 758 40 276 60 B85

302 0.15 2.00 0 045 0 030 1.00 17 00 19 00 8 00 10.00 90 612 40 276 50 B85

302B 0.15 2 00 0 045 0 030 2.00 3.00 17 00 19 00 8.00 10.00 95 655 40 276 55 B85

303 0.15 2.00 0 20 0.15 ml-) 1 00 17.00 19.00 8 00 10 00 0 60 90 621 35 241 50 (Bar)

303Se 0.15 2.00 0 20 0 060 1 00 17.00 19.00 8 00 10 00 0 15Se mn) 90 621 35 241 50 (Bar)

304 0.08 2.00 0 045 0.030 1 00 18 00 20.00 8 00 10.50 84 579 42 290 55 B80

304L 0.030 2.00 0.045 0.030 1 00 18 00 20.00 8 00 12 00 81 558 39 269 55 B79

S30430 0.08 2.00 0.045 0.030 1.00 17.00 19.00 8.00 10.00 3.00/4.00Cu 73 503 31 214 70 B70 (Wire)

304N 0.08 2.00 0 045 0.030 1 00 18 00 20.00 8 00 10.50 0.1010.16N 90 621 48 331 50 885

305 0.12 2.00 0.045 0.030 1.00 17.00 1900 10.501300 85 586 38 262 50 B80

308 0.08 2 00 0.045 0 030 1.00 19 00 21.00 10 00 12.00 115 793 80 552 40 (Wire)

309 0.20 2.00 0.045 0 030 1.00 22 00 24 00 12 00 15 00 90 621 45 310 45 B85

309S 0.08 2.00 0.045 0 030 1.00 22 00 24.00 12 00 15.00 90 621 45 310 45 B85

310 0.25 2.00 0.045 0 030 1.50 24 00 26.00 19.00 22.00 95 655 45 310 45 B85

310S 0.08 2.00 0.045 0 030 1.50 24 00 26 00 19.00 22 00 95 655 45 310 45 B85

314 0.25 2.00 0.045 0 030 1.50 3 00 23.00 26 00 19 00 22.00 100 689 50 345 40 B85

316 0 08 2.00 0.045 0 030 1.00 16 00 18.00 10.00.14.00 2 00 3.00 84 579 42 290 50 B79

316F 0.08 2.00 0 20 0.10mn 1 00 16.00 18.00 10.00 14.00 1.75 2 50 85 586 38 262 60 B85

316L 0.030 2.00 0 045 0.030 1 00 16 00 18.00 10.00 14.00 2.00 300 81 558 42 290 50 879

316N 0.08 2.00 0.045 0.030 1.00 16 00 18 00 10.00 14 00 2.00 3 00 0.1010.16N 90 621 48 331 48 B85

317 0.08 2.00 0.045 0.030 1.00 18.00 20.00 11.00 15.00 3.00 400 90 621 40 276 45 B85

317L 0.030 2.00 0.045 0.030 1.00 18.0020.00 11.0015.00 3004.00 86 593 38 262 55 B85

317LMN 0.030 2.00 0045 0.030 0.75 17.00120.00 13.50/17.50 400/500 0.10,'0.20N 96 662 54 373 49 B88

321 0 08 2.00 0.045 0.030 1.00 17.00 19 00 9.00 12.00 5xC Ti m 90 621 35 241 45 B80

330 0.08 2 00 0.040 0.030 0.75 1.50 17.00 20.00 34.00 37.00 0.10Ta 80 552 38 262 40 880 0.20Cb

347 0 08 2.00 0.045 0.030 1.00 17 00 19.00 9.00 13.00 1OxC 95 655 40 276 45 B85 Cb ()

348 008 2.00 0.045 0.030 1.00 17.00 19.00 9.00 13.00 Cb + Ta 1 xC ( ) 95 655 40 276 45 B85 Ta 0.10 -ax Co 0.20 max 384 0.08 2.00 0.045 0.030 1.00 15 00 17 00 17 00 19.00 75 517 35 241 55 B70 (Wire)

' May be added at manufacturer's option.

8 MECHANICAL AND PHYSIbAL New Design Specification two notations in this specification: PROPERTIES (Room Temperature) Until recently, design engineers want- (1)The maximum thickness for Type Austenitic Stainless Steels ing to use austenitic stainless steels struc- 409 ferritic stainless used in the standard The austenitic stainless steels cannot turally had to improvise due to the lack of is limited to 0.15 inches. be hardened by heat treatment but can an appropriate design specification. The (2)The maximum thickness for Type be strengthened by cold work, and thus familiar American Institute for Steel Con- 430 and 439 ferritic stainless steels is they exhibit a wide range of mechanical struction and AISI design specifications limited to 0.125 inches. properties. At room temperature, for carbon steel design do not apply to This is in recognition of concerns for austenitic stainless steels exhibit yield the design of stainless steel members the ductile to brittle transition temperature strengths between 30 and 200 ksi because of differences in strength of the ferritic stainless steels in structural (207-1379 MPa), depending on composi- properties, modulus of elasticity, and the application. It should be noted that these tion and amount of cold work. They also shape of the stress strain curve. Figure 17 alloys have been used in plate thickness exhibit good ductility and toughness even shows that there is no well-defined yield for other applications. at high strengths, and this good ductility point for stainless steel. Generally, toughness in the annealed and toughness is retained at cryogenic condition decreases as the chromium temperatures. The chemical composi- Table 9 content increases. Molybdenum tends to tions and nominal mechanical properties TYPICAL ENDURANCE LIMITS OF increase ductility, whereas carbon tends of annealed austenitic stainless steels are ANNEALED CHROMIUM-NICKEL to decrease ductility. Ferritic stainless given in Table 8. STAINLESS STEEL SHEET (2) steels can be used for structural applica- The difference in effect of cold work of tions (as noted above), as well as such AISI Endurance traditional applications as kitchen sinks, Types 301 and 304 is indicated by the Type limit, ksi MPa stress strain diagrams in Figure 11. and automotive, appliance, and luggage Carbon and nitrogen contents affect 301 35 241 trim, which require good resistance to yield strength, as shown by the differ- 302 34 234 corrosion and bright, highly polished ences among Types 304, 304L, and 303 35 241 finishes. 304 35 241 When compared to low-carbon steels, 304N. The effect of manganese and nitro- 316 39 269 gen on strength can be seen by compar- such as SAE 1010, the standard num- 321 38 262 bered AISI ferritic stainless steels, (such ing Types 301 and 302 against Types 201 347 39 269 and 202. as Type 430) exhibit somewhat higher yield and tensile strengths, and low elon- Figures 12, 13,14, and 15 illustrate Now the American Society of Civil other effects of small composition gations. Thus, they are not as formable as Engineers (ASCE), in conjunction with the the low-carbon steels. The proprietary fer- changes. For example, at a given amount SSINA, has prepared a standard of cold work, Types 202 and 301 exhibit ritic stainless steels, on the other hand, (ANSI/ASCE-8-90) "Specification for the with lower carbon levels have improved higher yield and tensile strengths than Design of Cold-Formed Stainless Steel Types 305 and 310. ductility and formability comparable with Structural Members." This standard that of low-carbon steels. Because of the Austenitic stainless steels which can be covers four types of austenitic stainless cold worked to high tensile and yield higher strength levels, the ferritic stainless steel, specificially Types 201, 301, 304 steels require slightly more power to strengths, while retaining good ductility and 316, and three types of ferritic stain- and toughness, meet a wide range of form. less steels (See Ferritic section below). Micro cleanliness is important to good design criteria. For example, sheet and This standard requires the use of struc- strip of austenitic steels - usually Types formability of the ferritic types because tural quality stainless steel as defined in inclusions can act as initiation sites for 301 and 201 - are produced in the fol- general by the provisions of the American lowing tempers: cracks during forming. Society for Testing and Materials (ASTM) Type 405 stainless is used where the specifications. annealed mechanical properties and cor- Tensile Yield Some of the physical properties of Strength Strength rosion resistance of Type 410 are satisfac- austenitic stainless steels are similar to tory but when better weldability is Temper Minimum Minimum those of the martensitic and ferritic stain- ksi MPa ksi MPa desired. Type 430 is used for formed less steels. The modulus of elasticity, for products, such as sinks and decorative example, is 28 x 106 psi (193 GPa) and trim. Physical properties of Type 430 are 1/4-Hard 125 862 75 517 density is 0.29 lb. per cu. in. (8060 Kg/iM3). 1/2-Hard 150 1034 110 758 shown in Table 10. Types 434 and 436 3 The physical properties of annealed Type are used when better corrosion resis- /4-Hard 175 1207 135 931 304 are shown in Table 10. Full-Hard 185 1276 140 965 tance is required and for relatively severe stretching. Ferritic Stainless Steels For fasteners and other machined In structural applications, the tough- Ferritic stainless steels contain approxi- parts, Types 430F and 430F Se are often ness and fatigue strength of these steels mately 12% chromium (and up). The used, the latter being specified when are important. At room temperature in the chemical composition of the standard forming is required in addition to annealed condition, the austenitic steels grades are shown in Table 11 along with machining. exhibit Charpy V-notch energy absorption nominal mechanical properties. Also Types 442 and 446 are heat resisting values in excess of 100 ft.-lb. The effect of several proprietary grades (see Appendix grades. cold rolling Type 301 on toughness is A) have achieved relatively wide commer- Type 409, which has the lowest chro- illustrated in Figure 16. This shows Type cial acceptance. mium content of the stainless steels, is 301 to have good toughness even after Three ferritic stainless steels, namely widely used for automotive exhaust cold rolling to high tensile strengths. Types 409, 430 and 439 are included in systems. Fatigue or endurance limits (in bend- the ASCE "Specification for the Design of ing) of austenitic stainless steels in the Cold-Formed Stainless Steel Structural annealed condition shown in Table 9 are Members." Designers should be aware of about one-half the tensile strength.

9 Table 10 PHYSICAL PROPERTIES OF GENERAL-PURPOSE STAINLESS STEELS (ANNEALED) (1) Type 304 Type 430 Type 410 S13800. Modulus of Elasticity in Tension psi x 1 06 (GPa) 28.0 (193) 29.0 (200) 29.0 (200) 29.4 (203) Modulus of Elasticity in Torsion 6 psi x 10 (GPa) 12.5 (86.2) ------Density, lbs/in3 (kg/M3) 0.29 (8060) 0.28 (7780) 0.28 (7780) 0.28 (7780) Specific Heat, Btu/lb/F (J/kgoK) 32-212F (0-100C) 0.12 (503) 0.11 (460) 0.11 (460) 0.11 (460)

Thermal Conductivity, Btu/hr/ft/F (Wm *K) 212F(100C) 9.4 (0.113) 15.1 (0.182) 14.4 (0.174) 8.1 (0.097) 932F(500C) 12.4 (0.149) 15.2 (0.183) 16.6 (0.201) 12.7 (0.152)

Mean Coefficient of Thermal Expansion x1 0-6 /F (xl 0-6/C) 32-212F (0-100C) 9.6 (17.3) 5.8 (10.4) 5.5 (9.9) 5.9 (10.6) 32-600F (0-315C) 9-9 (17.9) 6.1 (11.0) 6.3 (11.4) 6.2 (1 1.2) 32-1 OOF (0-538C) 10.2 (18.4) 6.3 (11.4) 6.4 (11.6) 6.6 (11.9) 32-1200F 0-648C) 10.4 (18.8) 6.6 (11.9) 6.5 (11.7) - _ 32-1800F (0.982C) -- 6.9 (12.4) 32-1500F_ -- --

Melting Point Range F 2550 to 2650 2600 to 2750 2700 to 2790 2560 to 2625 (C) (1398 to 1454) (1427 to 1510) (1483 to 1532) (1404 to 1440)

Table 11 FERRITIC STAINLESS STEELS (1) Chemical Analysis % (Max. unless noted otherwise)

Type C Mn P S X Cr Ni Mo Other

405 0.08 1.00 0.040 0.030 1 1.00 11.50/14.50 0.60 0.10/0.30 Al 409 0.08 1.00 0.045 0.045 1.00 10.50/11.75 0.50 6xC/0.75 Ti 429 0.12 1.00 0.040 0.030 1.00 14.00/16.00 0.75 430 0.12 1.00 0.040 0.030 1 1.00 I 16.00/18.00 0.75 430F 0.12 1.25 0.060 0.15(rmin)l 1.00 16.00/18.00 0.60- 430F Se 0.1 2 1.25 0.060 0.060 1 00 16.00/18.00 0.15 Se (min.) 434 0.12 1.00 0.040 0.030 1.00 16.00/18.00 0.75/1.25 436 012 1.00 0.040 0.030 1.00 16.00/18.00 0.75/1.25 5xC/0.70 Cb+Ta 442 0.20 1.00 0.040 0.030 1.00 18.00/23.00 0.60 446 0.20 1.50 0.040 0.030 1.00 23.00/27.00 0.75 0.25N

*May be added at manufacturer's option

Nominal Mechanical Properties (Annealed sheet unless noted otherwise)

Type Tensile Strength Yield Strength Elongation i H ksi MPa ksi MPa e/ (Rockwell) Form

405 65 448 I 40 276 25 B75 409 65 448 I 35 241 25 B75 429 70 483 ! 40 276 30 B80 (Plate) 430 75 517 50 345 25 B85 430F 95 655 85 586 10 B92 430F Se 95 655 85 586 10 B92 (Wire) 434 77 531 53 365 23 B83 436 77 531 53 365 23 B83 442 80 552 45 310 20 B90 (Bar) 446 80 552 50 345 20 B83

10 Martensitic Stainless Steels Impact tests on martensitic grades The densities of the martensitic stain- The martensitic grades are so named show that toughness tends to decrease less steels (about 0.28 lb. per cu. in.) because when heated above their critical with increasing hardness. High-strength (7780 Kg/iM3) are slightly lower than those temperature (1600F or 870C) and cooled (high-carbon) Type 440A exhibits lower of the carbon and alloy steels. As a result, rapidly, a metallurgical structure known toughness than Type 410. Nickel they have excellent vibration damping as martensite is obtained. In the hard- increases toughness, and Type 414 has a capacity. ened condition the steel has very high higher level of toughness than Type 410 The martensitic stainless steels are strength and hardness, but to obtain opti- at the same strength level. generally selected for moderate resis- mum corrosion resistance, ductility, and Martensitic grades exhibit a ductile- tance to corrosion, relatively high impact strength, the steel is given a brittle transition temperature at which strength, and good fatigue properties stress-relieving or tempering treatment notch ductility drops very suddenly. The after suitable heat treatment. Type 410 is (usually in the range 300-700F transition temperature is near room tem- used for fasteners, machinery parts and (149-371C)). perature, and at low temperature about press plates. If greater hardenability or Tables 12, 13 and 14 give the chemical -300F (-184C) they become very brittle, as higher toughness is required, Type 414 compositions and mechanical properties shown by the data in Figure 19. This may be used, and for better machinabil- of martensitic grades in the annealed and effect depends on composition, heat ity, Types 416 or 416 Se are used. hardened conditions. treatment, and other variables. Springs, flatware, knife blades, and hand The martensitic stainless steels fall into Clearly, if notch ductility is critical at tools are often made from Type 420, while two main groups that are associated with room temperature or below, and the steel Type 431 is frequently used for aircraft two ranges of mechanical properties: is to be used in the hardened condition, parts requiring high yield strength and low-carbon compositions with a maxi- careful evaluation is required. If the mate- resistance to shock. Cutlery consumes mum hardness of about Rockwell C45 rial is to be used much below room tem- most of Types 440A and B,whereas Type and the higher-carbon compositions, perature, the chances are that 440C is frequently used for valve parts which can be hardened up to Rockwell quenched-and-tempered Type 410 will requiring good wear resistance. C60. (The maximum hardness of both not be satisfactory. While its notch ductil- High-carbon martensitic stainless steels groups in the annealed condition is about ity is better in the annealed condition are generally not recommended for Rockwell C24.) The dividing line between down to -10oF (-73C), another type of welded applications, although Type 410 the two groups is a carbon content of stainless steel is probably more can be welded with relative ease. approximately 0.15%. appropriate. Hardening heat treatments should follow In the low-carbon class are Types 410, The fatigue properties of the marten- forming operations because of the poor 416 (a free-machining grade) and 403 (a sitic stainless steels depend on heat treat- forming qualities of the hardened steels. "turbine-quality" grade). The properties, ment and design. A notch in a structure performance, heat treatment, and fabrica- or the effect of a corrosive environment tion of these three stainless steels are can do more to reduce fatigue limit than similar except for the better machinability alloy content or heat treatment. of Type 416. Figure 20 gives fatigue data for Type On the high-carbon side are Types 403 turbine quality stainless at three test 440A, B,and C. temperatures. The samples were smooth Types 420, 414, and 431, however, do and polished, and the atmosphere was not fit into either category. Type 420 has a air. minimum carbon content of 0.15% and is Another important property isabrasion usually produced to a carbon specifica- or wear resistance. Generally, the harder tion of 0.3-0.4%. While it will not harden to the material, the more resistance to abra- such high values as the 440 types, it can sion it exhibits. In applications where cor- be tempered without substantial loss in rosion occurs, however, such as in coal corrosion resistance. Hence, a combina- handling operations, this general rule tion of hardness and adequate ductility may not hold, because the oxide film is (suitable for cutlery or plastic molds) is continuously removed, resulting in a high attained. apparent abrasion/corrosion rate. Types 414 and 431 contain 1.25- Other mechanical properties of marten- 2.50% nickel, which is enough to sitic stainless steels, such as compressive increase hardenability, but not enough to yield shear strength, are generally similar make them austenitic at ambient temper- to those of carbon and alloy steels at the ature. The addition of nickel serves two same strength level. purposes: (1)it improves corrosion resis- Room-temperature physical properties tance because it permits a higher chro- of Type 410 are shown in Table 10. The mium content, and (2)it enhances property of most interest is modulus of toughness. elasticity. The moduli of the martensitic Martensitic stainless steels are subject stainless steels (29 x 106 psi) (200 GPa) to temper embrittlement and should not are slightly less than the modulus of car- be heat treated or used in the range of bon steel (30 x 106 psi) (207 GPa) but are 800 to 105OF (427-566C) if toughness is markedly higher than the moduli of other important. The effect of tempering in this engineering materials, such as aluminum range is shown by the graph in Figure 18. (10 x 106 psi) (67 GPa). Tempering is usually performed above this temperature range.

11 Table 12 MARTENSITIC STAINLESS STEELS (1) Chemical Analysis % (Max. unless noted otherwise) Type C Mn P S Si Cr Ni Mo Other

403 0.15 1.00 0.040 0.030 0.50 11.50/13.00 410 0.15 1.00 0.040 0.030 1.00 11.50/13.50 414 0.15 1.00 0.040 0.030 1.00 11.50/13.50 1.25/2.50 416 0.15 1.25 0.060 0.15 (Min) 1.00 12.00/14.00 0.60^ 416 Se 0.15 1 25 0.060 0.060 1.00 12.00/14.00 0.15 Se (Min.) 420 0.1 5(Min.) 1.00 0.040 0.030 1.00 12.00/14.00 420 F 0.1 5(Min.) 1.25 0.060 0.15 (Min.) 1.00 12.00/14.00 0.60- 422 0.20/0.25 1.00 0.025 0.025 0.75 11.00/13.00 0.50/1.00 0.75/1.25 0.15/0.30 V 0.75/1.25 W 431 0.20 1.00 0.040 0.030 1.00 15.00/17.00 1.25/2.50 440A 0.60/0.75 1.00 0.040 0.030 1.00 16.00/18.00 0.75 440B 0.75/0.95 1.00 0.040 0.030 1.00 16.00/18.00 0.75 440C 0.95/1.20 1.00 0.040 0.030 1.00 16.00/18.00 0.75

'May be added at manufacturer's option

Table 13 Nominal Mechanical Properties (Annealed sheet unless noted otherwise) Tensile Strength Yield Strength Elongation in Type (0.2%offset) 2" (50.80 mm) Hardness Product ksi MPa ksi MPa (Rockwell) Form

403 70 483 45 310 25 B80 410 70 483 45 310 25 680 414 120 827 105 724 15 B98 416 75 517 40 276 30 B82 (Bar) 416Se 75 517 40 276 30 B82 (Bar) 420 95 655 50 345 25 B92 (Bar) 420F 95 655 55 379 22 220 (Brinell) (Bar) 422' 145 1000 125 862 18 320 (Brinell) (Bar) 431 125 862 95 655 20 C24 (Bar) 440A 105 724 60 414 20 B95 (Bar) 440B 107 738 62 427 18 B96 (Bar) 440C 110 758 65 448 14 B97 (Bar)

'Hardened and Temtpered

Precipitation Hardening Stainless Steels The principle of precipitation hardening (1793 MPa) (tensile) can be achieved - age hardened conditions. is that a supercooled solid solution (solu- exceeding even those of the martensitic Precipitation hardening stainless steels tion annealed material) changes its metal- stainless steels - while corrosion resis- have high strength, relatively good ductil- lurgical structure on aging. The principal tance is usually superior - nearly equal ity, and good corrosion resistance at advantage is that products can be fabri- to that of Type 304 stainless. Ductility is moderate temperatures. They are utilized cated in the annealed condition and then similar to corresponding martensitic for aerospace structural components, fuel strengthened by a relatively low- grades at the same strength level. Table tanks, landing gear covers, pump parts, temperature 900-1150F (482-620C) treat- 15 shows the chemical composition and shafting, bolts, saws, knives, and flexible ment, minimizing the problems the nominal mechanical properties of four bellows-type expansion joints. associated with high-temperature treat- AISI standard precipitation hardening Physical properties of UNS S13800 are ments. Strength levels of up to 260 ksi stainless steels in solution treated and shown in Table 10.

12 Table 14 NOMINAL MECHANICAL PROPERTIES As Quenched Hardness and Properties After Hardening and Tempering 1 in. (25.4 mm) Diameter Bars As Ouenched Tempered Hardness Tensile Yield Str. Elon, in. Red. of Izod Impact Hardness Hardening Tempering Strength, ksi 0.2 % 2 in. (50.80 mm) Area V-Notch Type UNS Temp. F. (C) HB HR Temp. F. (C) (MPa) Offset ksi (MPa) % % Ft. Lbs. (J) HB HR

403 and S40300 1800 (981) 410 C43 400 (204) 190(1310) 145(1000) 15 55 35 (47) 390 C41 410 S41000 600 (315) 180(1241) 140 (965) 15 55 35 (47) 375 C39 800- (426) 195(1344) 150(1034) 17 55 390 C41 1000^ (538) 145 (1000) 115 (793) 20 65 300 C31 1200 (648) 110 (758) 85 (586) 23 65 75 (102) 225 B97 1400 (760) 90 (621) 60 (414) 30 70 100 (136) 180 B89 416and S416001800 (981) 410 C43 400 (204) 190(1310) 145 (1000) 12 45 20 (27) 390 C41 416Se S41623 600 (315) 180(1241) 140 (965) 13 45 20 (27) 375 C39 800- (426) 195 (1344) 150 (1034) 13 50 390 C41 1000-(538) 145(1000) 115 (793) 15 50 300 C31 1200 (648) 110 (758) 85 (586) 18 55 30 (41) 225 B97 1400 (760) 90 (621) 60 (414) 25 60 60 (81) 180 B89 414 S41400 1800 (981) 425 C44 400 (204) 100(1379) 150(1034) 15 55 45 (61) 410 C43 600 (315) 190(1310) 145 (1000) 15 55 45 (61) 400 C41 800 (426) 200(1379) 150(1034) 16 58 415 C43 1000- (538) 145 (1000) 120 (827) 20 60 290 C30 1200 (760) 120 (827) 105 (724) 20 65 50 (68) 250 C22 431 S431001900(1036) 440 C45 400 (204) 205(1413) 155(1069) 15 55 30 (41) 415 C43 600 (315) 195(1344) 150 (1034) 15 55 45 (61) 400 C41 800-(426) 205 (1413) 155 (1069) 15 60 415 C43 1000- (538) 150 (1034) 130 (896) 18 60 325 C34 1200 (760) 125 (862) 95 (655) 20 60 50 (68) 260 C24 420 S42000 1900 (1036) 540 C54 600 (315) 230(1586) 195(1344) 8 25 10 (14) 500 C50 440A S440021900(1036) 570 C56 600 (315) 260(1793) 240(1655) 5 20 4 (5) 510 C51 440B S44003 1900 (1036) 590 C58 600 (315) 280 (1931) 270 (1862) 3 15 3 (4) 555 C55 440C S44004 1900 (1036) 610 C60 600 (315) 285 (1965) 275 (1896) 2 10 2 (3) 580 C57

'Tempering within the range of 750 to 1050 F (399 to 565 C) is not recommended because such treatment will result in low and erratic impact properties and loss of corrosion resistance. Note. Variations in chemical composition within the individual type ranges may affect the mechanical properties.

Table 15 PRECIPITATION HARDENING STAINLESS STEELS (1) Chemical Analysis % (Max. unless noted otherwise) Type C Mn P S Si Cr Ni Mo Other

S13800 0.05 0.10 0.010 0.008 0.10 12.25/13.25 7.50/8.50 2.00/2.50 0.90/1.35Al 0.01 0 N S15500 0.07 1.00 0.040 0.030 1.00 14.00/15.50 3.50/5.50 2.50/4.5 Cu 0.1 5/0.45 Gb + Ta S17400 0.07 1.00 0.040 0.030 1.00 15.50/17.50 3.00/5.00 3.00/5.00 Cu 0.15/0.45 Gb + Ta S17700 0.09 1.00 0.040 0.040 0.040 16.00/18.00 6.50/7.75 0.75/1.50 Al

Nominal Mechanical Properties (Solution Treated Bar)

Tensile Strength Yield Strength Elongation in Hardness Type (0.2% offset) 2' (50.80 mm) Hrns ksi MPa ksi MPa % (Rockwell)

S13800 160 1103 120 827 17 C33 S15500 160 1103 145 1000 15 C35 S17400 160 1103 145 1000 15 C35 S17700 130 896 40 276 10 B90

13 HIGH-TEMPERATURE temperature service, ASTM has estab- 885F embrittlement results in low duc- MECHANICAL PROPERTIES lished an H" modification of some AISI tility and increased hardness and tensile Stainless steels are used at tempera- numbered stainless steels. This modifica- strengths at room temperature, and the tures up to about 2000F (1093C) tion establishes a minimum carbon level metal may fracture catastrophically if not because they have good strength at in grades such as 304H and 321H when handled carefully. The metal, however, elevated temperature and good resis- the intended application requires good retains its desirable mechanical proper- tance to corrosion and oxidation. high temperature properties. ties at operating temperature (500F and In steam power generation, for exam- Welding can affect high-temperature higher). The effect of 885F embrittlement ple, high allowable design stresses permit rupture and creep strength characteris- can be removed by heat treatment at the use of thin sections and high operat- tics. Nevertheless, good welding prac- 110OF (593C). ing temperatures. In aircraft and space- tices result in reliable values. Ferritic and duplex grades are subject craft design, the AISI numbered stainless Pressure vessels and other elevated- to sigma-phase embrittlement when steels are used for parts in which hot temperature equipment are designed to exposed to temperatures of 1000-1800F strength is crucial. Stainless steels are American Society of Mechanical (538-987C) over extended periods, which used extensively in heat exchangers in Engineers Boiler and Pressure Vessel also results in loss of room-temperature which there is need for both corrosion Codes. These represent an excellent ductility and corrosion resistance. Sigma- resistance and hot strength, especially for compendium of minimum requirements phase can be removed by heat treatment pressure service. The nuclear power for design, fabrication, inspection and for ferritic grades at 1650F (899C) fol- industry represents many high- construction. Designers should refer to lowed by air cooling, and at 1900F temperature applications for stainless the latest applicable revisions that reflect (1038C), and higher for duplex grades. steels, such as superheaters, boilers, current technology. Carbide precipitation occurs (see sec- feed-water heaters, valves, and main tion on corrosion) in austenitic stainless steam lines. THERMAL STABILITY steels in the temperature range of At steam temperatures over 105OF With time and temperature, changes in 800-1600F (427-871C). This causes a loss (566C), the austenitic stainless steels are metallurgical structure can be expected of toughness and may make the steel preferred. This is illustrated by Table 16, for almost any steel or alloy. In stainless subject to intergranular corrosion in cer- which shows allowable stresses for Type steels, the changes can be softening, car- tain environments. It can be removed by 304 seamless pipe in unfired vessels, as bide precipitation, or embrittlement. heat treatment above 1900F (1038C). compared with a low-alloy chromium- Softening occurs in the martensitic Brittle failure under load is of concern, molybdenum steel. stainless steels when exposed to temper- especially in welded fabrications. This In analyzing high-temperature proper- atures approaching or exceeding the type of embrittlement is largely a problem ties, hot strength and thermal stability original tempering temperature. Type at temperatures of 1000-1500F (from the standpoint of softening or 440C, for example, can be held at 900F (538-816C), since strength and not ductil- embrittlement) are important. Physical (482C) for only short periods if the high ity is the limiting factor at higher tempera- properties are also significant. hardness is to be retained. Cold-worked tures. Because of difficulty in evaluating Figure 21 gives a broad concept of the austenitic stainless steels, as shown previ- data, and the variable conditions hot-strength advantages of stainless ously in Figure 22, may also soften at involved, designers are encouraged to steels in comparison to low-carbon unal- elevated temperature. seek technical assistance from stainless loyed steel. Precipitation hardening stain- Embrittlement usually means the loss steel producers (see inside back cover). less steels also have excellent hot of room-temperature toughness. Embrit- Physical properties such as linear strength at moderate temperatures, but tled equipment must be handled carefully expansion and thermal conductivity are their strength declines sharply as they to avoid impact when it is cooled down of interest. Figure 28 shows austenitic overage at high temperature. for maintenance. Table 19 shows how stainless steels to have greater thermal Figure 22 compares the effect of tem- prolonged holding at temperatures of expansion than martensitic or ferritic perature on the strength and ductility of 900 to 1200 F (482-649C) can affect grades. This should be considered when annealed vs. cold worked Type 301. room-temperature toughness of various joining dissimilar metals. Above 100OF (537C), design will be stainless steels, while Figure 27 puts Thermal conductivity is also different based on creep or rupture strength. embrittlement in better perspective with among different stainless steels. However, Figure 23 shows short-time tensile and respect to the three "general-purpose" in heat exchange applications, film resis- yield strengths of various stainless steels. types. Note that the transition tempera- tance, fouling, and other surface factors Table 17 shows creep and rupture ture for Types 410 and 430 is near room have a far greater effect on heat transfer strengths of annealed 400 Series stain- temperature, while there is only minor than the alloy itself. less steels exposed to temperatures up to loss of toughness in Type 304. Embrittle- Fluctuating thermal stresses, resulting 150OF (816C), while Table 18 shows data ment is rarely of concern with austenitic from periodic changes in temperature, for five stainless steels at 1600-2000F stainless steels. can lead to fatigue problems. A rule of (871-1093C). Figures 24, 25, and 26 show Ferritic and duplex stainless steels are thumb has been used with apparent suc- comparative 100,000 hour stress-rupture subject to embrittlement when exposed cess: For a 20-year life, a figure of 7000 data for Types 304, 321, and 347, respec- to temperatures of 700-950F over an cycles - corresponding to one cycle a tively. extended period of time. Martensitic day - has been used in piping design, These data generally apply to stainless grades with greater than 12% chromium while 40,000 is the number of tempera- steels normally furnished by mills, but it also have been known to display brittle ture swings for process equipment over should be recognized that processing tendencies after extended periods in the the same period. The 300 Series stain- variables can occur. To minimize such same temperature range. This phenome- less steels are more sensitive to thermal variables in materials for high- non is called 885F embrittlement fatigue than the 400 Series types. because of the temperature at which embrittlement is most rapid.

14 Table 16 ALLOWABLE STRESS AT MAXIMUM METAL TEMPERATURE (2) F 900 950 1000 1050 1100 1150 1200 C 482 510 538 566 593 621 649 Type ksi MPa ksi MPa ksi MPa ksi MPa ksi MPa ksi MPa ksi MPa 304 10.0 68.9 9.8 67.2 9.5 65.2 9.0 62.1 8.3 56.9 6.9 47.6 5.5 37.9 2/4Cr-1 Mo 13.1 90.3 11.0 75.8 7.8 53.8 5.8 40.0 4.2 29.0 3.0 20.7 2.0 13.8

Table 17 RUPTURE AND CREEP CHARACTERISTICS OF CHROMIUM STAINLFS STFELS IN ANNFALED COND1ITION () F 800 900 1000 1 1100 1 1200 1300 1400 1500 C 427 482 538 593 I 649 704 760 861 Type ksi MPa ksi MPa ksi MPa Iksi MPa | ksi MPa ksi MPa ksi MPa ksi MPa

Stress for rupture in 1000 hours 405 -- 25.0 172 16.0 110 6.8 47 3.8 27 2.2 15 1.2 8 0.8 6 410 54.0 372 34.0 234 190 131 10.0 69 4.9 34 2.5 18 1.2 8 -- 430 -- 30.0 207 17.5 120 9.1 63 5.0 34 2.8 2.0 1.7 12 0.9 6 446 _ --- 17.9 123 5.6 39 4.0 28 2.7 19 1.8 13 1.2 8 Stress for rupture in 10.000 hours 405 -- 22.0 152 12.0 83 4.7 33 2.5 18 1.4 10 0.7 5 0.4 3 410 42.5 294 26.0 179 13.0 90 6.9 47 3.5 24 1.5 10 0.6 4 -- 430 -- 24.0 165 13.5 94 6.5 43 3.4 23 2.2 15 0.7 5 0.5 3 446 ---- 13.5 94 3.0 21 2.2 15 1.6 1 1.1 8 0.8 6

Stress for creep rate of 0.0001% per hour 405 -- 43.0 296 8.0 55 2.0 14 -- _ -- --- 410 43.0 296 29.0 200 9.2 63 4.2 29 2.0 14 1.0 7 0.8 6 -- 430 23.0 159 15.4 106 8.6 59 4.3 30 1.2 8 1.4 10 0.9 6 0.6 4 446 31.0 214 16.4 113 6.1 42 2.8 20 1.4 10 0.7 5 0.3 2 0.1 1

Stress for creep rate of 0.00001 % per hour 405 -- 14.0 97 4.5 32 0.5 3 -- _ ----- 410 19.5 135 13.8 96 7.2 49 3.4 24 1.2 8 0.6 4 0.4 3 -- 430 17.5 120 12.0 83 6.7 46 3.4 24 1.5 10 0.9 6 0.6 4 0.3 2 446 27.0 186 13.0 90 4.5 32 1.8 13 08 6 0.3 2 0.1 1 0.05 0.3

Table 18 RUPTURE AND CREEP CHARACTERISTICS OF CHROMIUM-NICKEL STAINLESS STEELS (1 7) Stress Extroplated Testing Rupture Time Creep Rate elogation at temperature 100 hr 1000 hr 10,000 hr 0.01% hr. rupture in Type °F °C ksi MPa ksi MPa ksi MPa ksi MPa 10,000 hr, % 302 1600 871 4.70 33 2.80 19 1.75 12 2.50 17 150 1800 982 2.45 17 1.55 11 0.96 7 1.30 9 30 2000 1093 1.30 9 0.76 5 0.46 3 .62 4 18 309S 1600 871 5.80 40 3.20 22 -- 3.50 24 - 1800 982 2.60 18 1.65 11 1.00 7 1.00 7 105 2000 1093 1.40 10 0.83 6 0.48 3 .76 5 42 310S 1600 871 6.60 45 4.00 28 2.50 17 4.00 28 30 1800 982 3.20 22 2.10 15 1.35 9 1.75 12 60 2000 1093 1.50 10 1.10 7 0.76 5 .80 6 60 314 1600 871 4.70 32 3.00 21 1.95 13 2.30 16 110 1800 982 2.60 18 1.70 12 1.10 8 1.00 7 120 2000 1093 1.50 10 1.12 7 0.85 6 .90 6 82 316 1600 871 5.00 34 2.70 19 1.40 10 2.60 18 30 1800 982 2.65 18 1.25 9 0.60 4 1.20 8 35 2000 1093 1.12 8 0.36 2 -- 4.00 28 -

15 Table 19 EFFECT OF PROLONGED HOLDING AT 900-1200 F (482-649C) ON ROOM-TEMPERATURE TOUGHNESS AND HARDNESS (2) Room-Temperature Charpy keyhole Impact strength Room-temperature Brinell hardness after 1000 hr at after 10,000 hr at after 1000 hr at after 10,000 hr at Unexposed 900(482) 1050 (566) 1200F (649C) 900 (428) 1050 (566) 1200F (649C) Unex- 900 1050 1200F 900 1050 1200F Type ft-lb J ft-lb J ft-lb J ft-lb J ft-lb J ft-lb J ft-lb J posed (482) (566) (649C) (482) (566) (649C)

304 91 123 87 118 75 102 60 81 79 107 62 84 47 64 141 145 142 143 143 132 143 304L 82 111 93 126 76 103 72 98 85 115 71 96 63 85 137 140 134 134 143 143 143 309 95 129 120 163 85 115 43 58 120 163 51 69 44 60 109 114 109 130 140 153 159 310 75 102 - - 48 65 29 39 62 84 29 39 2 3 124 119 119 130 152 174 269 316 80 108 86 117 72 98 44 60 87 118 49 66 21 28 143 151 148 170 145 163 177 321 107 145 101 137 90 122 69 94 88 119 72 98 62 84 168 143 149 166 156 151 148 347 56 76 60 81 55 75 49 66 63 85 51 69 32 43 169 156 167 169 156 169 123 405 35 47 - - 36 49 26 35 -- 39 53 34 46 165 - 143 137 - 143 143 410 33 45 -- 41 56 27 37 39 53 3 4 21 28 143 - 114 154 124 143 128 430 46 62 -- 32 43 34 46 1 1 3 4 4 5 184 - 186 182 277 178 156 446 1 1- - 1 1 1 1 1 1 1 1 1 1 201 - 211 199 369 255 239

LOW-TEMPERATURE MECHANICAL PROPERTIES Table 20 Alloys for low-temperature service must TYPICAL MECHANICAL PROPERTIES OF STAINLESS STEELS AT have suitable engineering properties, CRYOGENIC TEMPERATURES (2) such as yield and tensile strengths and Yield Elonga- ductility. Experience with brittle fracture of Test Strength Tensile tion in steel ships during World War II demon- Type Temperature 0.2% Offset Strength 2" Izod Impact strated that many metals may have satis- F C ksi MPa ksi MPa % ft. lbs. J factory "room-temperature" characteristics but not perform ade- 304 - 40 - 40 34 234 155 1,069 47 110 149 quately at low temperatures. Low temper- - 80 - 62 34 234 170 1,172 39 110 149 -320 -196 39 269 221 1,524 40 110 149 ature brittle fracture can occur, -423 -252 50 344 243 1,675 40 110 149 sometimes with catastrophic failure, with- 310 - 40 - 40 39 269 95 655 57 110 149 out any warning by stretching, sagging, - 80 - 62 40 276 100 689 55 110 149 bulging or other indication of plastic fail- -320 -196 74 510 152 1,048 54 85 115 ure. Alloys that are ordinarily ductile may -423 -252 108 745 176 1,213 56 suddenly fail at very low levels of stress. 316 - 40 - 40 41 283 104 717 59 110 149 In the handling and storage of liquid - 80 - 62 44 303 118 814 57 110 149 gases at cryogenic temperatures, few -320 -196 75 517 185 1,276 59 steels can be used, Austenitic stainless -423 -252 84 579 210 1,448 52 347 - 40 - 40 44 303 117 807 63 110 149 steels are among these few because they - 80 - 62 45 310 130 896 57 110 149 exhibit good ductility and toughness at -320 -196 47 324 200 1,379 43 95 129 the most severe of cryogenic tempera- -423 -252 55 379 228 1,572 39 60 81 tures - minus 423F (-253C) and lower. 410 - 40 - 40 90 621 122 841 23 25 34 Table 20 shows tensile properties of - 80 - 62 94 648 128 883 22 25 34 several stainless steels at cryogenic tem- -320 -196 148 1,020 158 1,089 10 5 7 peratures. Austenitic grades show not 430 - 40 - 40 41- 283 76 524 36 10 14 only good ductility down to -423F - 80 - 62 44 303 81 558 36 8 11 (-253C), but they also show an increase -320 -196 87 607 92 634 2 2 3 in tensile and yield strengths. Toughness is also excellent as indicated by the impact strength values - although there is some decrease as tem- long periods of exposure and does not cold worked as much as 85% and still perature decreases. Table 21 shows exhibit any marked degradation of tough- exhibit a good notched-to-unnotched ten- results of impact tests on four austenitic ness. Properly made welds also have sile ratio down to -423F (-2530). Tests grades in different plate thicknesses, excellent low temperature properties. indicate that toughness levels at cryo- indicating that toughness is not markedly Austenitic grades cold worked to high genic temperatures are higher in cold affected by section size. Impact tests strength levels are also suitable for low worked Type 310 than in cold worked show that Type 304 is very stable over temperature service. Type 310 can be Type 301.

16 HEAT TRANSFER PROPERTIES Table 21 Stainless steels are used extensively for LOW-TEMPERATURE IMPACT STRENGTH OF SEVERAL ANNEALED heat exchangers because their ability to AUSTEN ITIC remain clean enhances heat transfer effi- STAINLESS STEELS (2) ciency. For example, Figure 29 illustrates Energy that films and scale on exchanger sur- AISI Testing Temp Specimen Type of absorbed, faces impair heat transfer to a far greater Type F C orientation notch Product size ft-lb J extent than the metal wall, which 304 -320 -196 Longitudinal Keyhole 3-in. plate 80 108 accounts for only 2% of the total resistance to heat flow. Table 22 supports this 304 -320 -196 Transverse Keyhole 3-in.plate 80 108 contention by showing that thermal con- 304 -320 -196 Transverse Keyhole 21/2-in. plate 70 95 ductivity of a metal has only a minor 304 -423 -252 Longitudinal Keyhole '/2-in. plate 80 108 effect on the "U" valve, or the overall 304 -423 -252 Longitudinal V-notch 3/2-in. plate 91.5 124 heat-transfer coefficient. 304 -423 -252 Transverse V-notch 31/2-in. plate 85 115 The degree to which other factors 73 99 affect heat transfer are dependent on the 304L -320 -196 Longitudinal Keyhole '/2-in. plate type of fluid involved, its velocity, and the 304L -320 -196 Transverse Keyhole '/2-in plate 43 58 nature of scale or forming buildup on the 304L -320 -196 Longitudinal V-notch 31/2-in plate 67 91 surface. Since corrosion and scale 304L -423 -252 Longitudinal V-notch 31/2-in. plate 66 90 accumulation is minimal with stainless 310 -320 -196 Longitudinal V-notch 31/2-in plate 90 122 steels, there would be less difference in 118 service performance among various 310 -320 -196 Transverse V-notch 31/2-in. plate 87 metals than would be indicated by ther- 310 -423 -252 Longitudinal V-notch 31/2-in. plate 86.5 117 mal conductivity data. The power genera- 310 -423 -252 Transverse V-notch 3/2-in. plate 85 115 tion industry, for instance, has very 347 -320 -196 Longitudinal Keyhole /2-in. plate 60 81 carefully analyzed transfer characteristics 347 -320 -196 Transverse Keyhole '/2-in. plate 47 64 of heat exchanger materials and has con- clusively demonstrated that stainless 347 -423 -252 Longitudinal V-notch 31/2-in. plate 59 80 steels behave in a manner far superior to 347 -423 -252 Transverse V-notch 3'/2-in. plate 53 72 other materials. 347 -300 -184 Longitudinal V-notch 61/2-in. plate 77 104 Figure 30 compares two condenser 347 -300 -184 Transverse V-notch 6X/2-in. plate 58 79 tubing materials exposed simultaneously to identical operating conditions. In the early stages of the test the relative perfor- both materials decreased with time, but are available from the Specialty Steel mance of both materials corresponded to that of the Admiralty brass was more Industry of North America. One is "A published thermal conductivity figures. rapid due to fouling and corrosion, while Discussion of Stainless Steels for Surface However, in only 240 days, the overall the stainless steel was affected only by Condenser and Feedwater Heater Tub- heat transfer rate of the stainless steel fouling. Similar results were observed in ing," and the other, "The Role of Stain- was found to surpass that of the desalination tests conducted in Freeport, less Steels in Industrial Heat Admiralty brass. The heat transfer rate for Texas. Two booklets on heat exchangers Exchangers."

Table 22 EFFECT OF METAL CONDUCTIVITY ON "U" VALUES (1 8) Film Coefficients Thermal Conductivity "U" Value Btu/hr/ft2/0 F of Metal Btu/hr/ft 2/0F/in. Btu/hr/ft2 /0 F Application Material (W/m 2eK) (W/m*K) (W/m 2*K)

Heating Copper 300 (1704) 1000 (5678) 2680 (387) 229 (1300) water with Aluminum 300 (1704) 1000 (5678) 1570 (226) 228 (1295) saturated Carbon Steel 300 (1704) 1000 (5678) 460 (66) 223 (1266) steam Stainless Steel 300 (1704) 1000 (5678) 105 (15) 198 (1124)

Heating Copper 5 (28) 1000 (5678) 2680 (387) 4.98 (28) air with Aluminum 5 (28) 1000 (5678) 570 (226) 4.97 (28) saturated Carbon Steel 5 (28) 1000 (5678) 460 (66) 4.97 (28) steam Stainless Steel 5 (28) 1000 (5678) 105 (15) 4.96 (28)

where h,=outside fluid film heat-transfer coefficient 1 hi=inside fluid film heat-transfer coefficient "U" = 1 + thickness of metal wall + 1 Stainless steel is 300 Series Type ho thermal conductivity h,

17 SHAPES, SIZES, AND FINISHES Polished finishes are produced by There are three standard finishes for Exhibit 1 illustrates mill processes for mechanical polishing, and sometimes by strip, which are broadly described by the making various stainless steel products. buffing, and are characterized by fine finishing operations employed: Because alloy composition must be very parallel grit lines - the fineness being No. 1 Strip Finish is approximately carefully controlled, various refining steps determined by the grit size used in the the same as No. 2D Sheet Finish. It varies are used in conjunction with electric fur- final step. These grit lines can impart a in appearance from dull gray matte to a nace (or vacuum furnace) melting and at directional character to the finish, which fairly reflective surface, depending largely the Argon Oxygen Decarburization when present should be considered in on alloy composition and amount of cold (AOD) vessel. Other refining steps are final product design. Some polished and reduction. vacuum arc, partial pressure inert gas buffed finishes are produced by some No. 2 Strip Finish isapproximately arc, electron beam, and electroslag con- mill and specialty processors. the same as a No. 2B sheet finish. It is sumable arc remelting practices. During Blast finishes are applied by conven- smoother, more reflective than No. 1, and these remelting steps, certain impurities tional blasting techniques using glass likewise varies with alloy composition. are reduced to minimum levels, and beads. Bright Annealed Finish is a highly inclusion levels are lowered. While finishes are usually selected for reflective finish that is retained by final During the final stages of producing appearance, selection cannot be made annealing in a controlled atmosphere basic mill forms - sheet, strip, plate, and independently of fabrication considera- furnace. bar - and bringing these forms to tions. For example, if evidence of Mill-Buffed Finish is a bright cold specific sizes and tolerances, the exposed welds is to be removed, rolled rolled, highly reflective finish obtained on materials are subjected to hot reduction nondirectional finishes are generally not either No. 2 or on bright annealed strip with or without subsequent cold rolling specified because they cannot be by continuously buffing in coil form. The operations, annealing, and cleaning. Fur- blended or refinished. A polished finish purpose of mill-buffing is to provide a uni- ther steps are required to produce other such as No. 4, on the other hand, can be form finish with regard to color and reflec- mill forms, such as wire and tubing. blended by matching grit size to that tivity. It can also provide a surface Table 23 shows how the mill forms are used for the original polish. It is also receptive to chromium plating. The finish classified by size, and Tables 24, 25, and important to consider the effects of vari- has wide use in automotive trim, house- 26 identify finishes and conditions in ous fabrication methods used in the hold trim, tableware, utensils, fire extin- which sheet, bar, and plate are available. manufacture of the stainless steel guishers, plumbing fixtures, etc. Finishes are produced by three basic products. Severe forming, for example, Because of the wide variety of standard methods. These are (1)rolling between can distort or locally remove grit lines, so and nonstandard finishes, designers are polished or textured rolls, (2) polishing it may be necessary to refinish the sur- encouraged to examine samples before and/or buffing with abrasive wheels, face after fabrication, such as in the selecting a finish. belts, or pads, and (3)blasting with abra- manufacture of pots and pans. sive grit or glass beads. The resulting sur- It should also be recognized that each FABRICATION face textures vary from the "natural" finish can have variations in appearance Stainless steels are generally selected, appearance produced by hot or cold roll- depending upon composition, thickness, first on the basis of corrosion resistance ing (or by extrusion) to mirror-bright method of application, and supplier. In and, second, on the basis of strength or surfaces. rolled finishes, the thinner the sheet, the other mechanical properties. A third-level Rolled finishes result from the initial smoother the surface. The 200 and 300 consideration is fabrication. While the forming of the metal at the mill. These are Series stainless steels have a charac- three general-purpose stainless types the simplest and usually the lowest in teristically different appearance than 400 predominate, namely Types 304, 430, cost, and they include a wide range of Series types. Color variations may occur and 410, there are variations of these appearance depending on the character among the different types within the types that are better suited to certain of the rolls themselves, which can be same metallurgical category. The prac- manufacturing operators. (Service highly polished or etched to produce a ticability of describing any of the finishes requirements may preclude the use of dull matte finish. in terms of measurable limits, such as for these variations, so it is well to know that Patterned finishes are also made by smoothness or reflectance, has not been all stainless steels can be readily fabri- rolling, and they are available in a wide established, so designers are cated by conventional manufacturing variety of sculptural designs and textures, encouraged to provide samples showing methods.) all of which are proprietary in nature and the final finish desired. The handbook "Stainless Steel Fabri- not included in AISI numbered finish Tables 24, 25, and 26, as mentioned cation" is available from the SSINA and designations. These are produced either previously, show AISI numbered finishes describes these alloys and various fabri- by passing mill-rolled finished sheet and conditions for sheet, bar and plate. cation methods. between two mating rolls of specific While there are no specific designations design or by impressing different patterns for polished finishes on bar or plate, the HOT FORMING on each side of the sheet. These finishes sheet finish designations are often used Stainless steels are readily formed by usually have the added advantage of stiff- to describe the desired effect. This also hot operations such as rolling, extrusion, ness. They are supplied by some mills applies to finishes on ornamental tubing. and forging - methods that result in and by specialty processors. finished or semifinished parts. Hot rolling is generally a steel mill operation for producing standard mill forms and special shapes. Exhibit 2 illustrates the variety of hot-rolled, cold-rolled, and cold-drawn shapes available in stainless steel bar. Exhibit 3 provides some design guidelines for extrusion. Forging is used extensively for stainless steels of all types (Exhibit 4).

18 Exhibit 1 The Making of Stainless Steel IL Blooming or Structural Slabbing Mill +1 Shapes

.| .! Blooms I Bar s Soaking Ingots Pit Billets ; Wire Rods, Wire Continuous Casting Alloys 1 + 9 oMolten - Electric AOD Stainless Steel Furnace Vessel Steel Cold Rolled Scrap Sheet, Strip ir and Plate Mill Pressure Casting Plates

Table 23 CLASSIFICATION OF STAINLESS STEEL PRODUCT FORMS (2) Dimensions Item Description Thickness Width Diameter or Size Sheet Coils and cut lengths: Mill finishes Nos. 1,2D & 2B under 3116" (4.76 mm) 24" (609.6 mm) & over Pol. finishes Nos. 3, 4, 6, 7 & 8 ,, ,, ,, all widths

Strip Cold finished, coils or cut lengths under 3/16" (4.76 mm) under 24" (609.6 mm) Pol. finishes Nos. 3, 4, 6, 7 & 8 ,, ,, ,, all widths

Plate Flat rolled or forged 3/16" (4.76 mm) & over over 10" (254 mm) Bar Hot finished rounds, squares, octagons and hexagons _ - 1/4"' (6.35 mm) & over Hot finished flats 1/8" (3.18 mm) to 1/4" (6.35 mm) to 8" (203 mm) incl. 10" (254 mm) incl. Cold finished rounds, squares, octagons and hexagons _ - over 1/8" (3.18 mm) Cold finished flats 1/8" (3.18 mm) to 3/8" (9.53 mm) to 41/2" (114 mm) 41/2" (114 mm) Wire Cold finishes only: (in coil) Round, square, octagon, hexagon, and flat wire under 3/16" (4.76 mm) under 3/8" (9.53 mm) Pipe & Tubing Several different classifications, with differing specifications, are available. For information on standard sizes consult your local Steel Service Center or the SSINA. Extrusions Not considered "standard" shapes, but of potentially wide interest. Currently limited in size to approximately 61/2" (165.1 mm) diameter, or structurals.

19 Table 24 STANDARD MECHANICAL SHEET FINISHES (2) Unpolished or Rolled Finishes: No. 4 A polished surface obtained by finishing with a 120-150 No. 1 A rough, dull surface which results from hot rolling to the mesh abrasive, following initial grinding with coarser specified thickness followed by annealing and descaling. abrasives. This is a general-purpose bright finish with a visible "grain" which prevents mirror reflection. No. 2D A dull finish which results from cold rolling followed by annealing and descaling, and may perhaps get a final light No. 6 A dull satin finish having lower reflectivity than No. 4 finish. roll pass through unpolished rolls. A 2 finish is used It is produced by Tampico brushing the No. 4 finish in a where appearance is of no concern. medium of abrasive and oil. It is used for architectural applications and ornamentation where a high luster is No. 2B A bright, cold-rolled finish resulting in the same manner as undesirable, and to contrast with brighter finishes. No. 2D finish, except that the annealed and descaled sheet receives a final light roll pass through polished rolls. This is No. 7 A highly reflective finish that is obtained by buffing finely the general-purpose cold-rolled finish that can be used as ground surfaces but not to the extent of completely remov- is, or as a preliminary step to polishing. ing the "grit" lines. It is used chiefly for architectural and ornamental purposes.

Polished Finishes; No. 8 The most reflective surface; which is obtained by polishing No. 3 An intermediate polish surface obtained by finishing with a with successively finer abrasives and buffing extensively 100-grit abrasive. Generally used where a semifinished until all grit lines from preliminary grinding operations are polished surface is required. A No. 3 finish usually receives removed. It is used for applications such as mirrors and additional polishing during fabrication. reflectors.

Exhibit 2

COLD-DRAWN SHAPES ... HOT-ROLLED SHAPES ... COLD-ROLLED SHAPES ...

For achieving superior mechanical prop- For applications where parts are made For applications where parts require close erties, lower machining costs, faster pro- from straight lengths, curved pieces; or tolerance, fine surface finishes, superior duction and reduced scrap loss. are to be formed into rings, welded and mechanical properties. finish-machined.

* * IV * w _ v -A A_ -J c iMdm Lui a%

Iltm -J

20 Exhibit 3 Extrusion Guidelines INSTEAD OF THIS CONSIDER THIS INSTEAD OF THIS CONSIDER THIS Indicates solid bar if part were machined

Avoid sharp knife-like edges _ 61/2", die circle 61/2- die circle

T~~~~~~~~~~~~~~~~~~~~~~

Keep depth to width ratio as Minn C osssection area low as possible w = d is .28 square inches

No holes in nonsymmetrical shapes Round Corners and fillets

Avoid extremely thicklthin T section junctions Extrude a modified shape cut

21 Exhibit 4 FORGING RANGES FOR STAINLESS STEELS C 800 900 1000 1100 1200 1300 Temperature, I i I I I i F 1400 1600 1800 2000 2200 2400 Type 440C h. Type 347 & 348 Type 321 Type 440B £ ____ Type 440A I Type 310 0

Type 3108 ____ _

Type 329 _ 0 a) Type 317

0 Type 316L ____ _ Type 316

Type 309S ___

Type 309 _ _ _ _ _

Type 303 Se Type 305 Type 302 & 304 Type 431

C- Type 414 0 Type 420F I Type 420

a1) Type 416 _

Type 410 __ _///

Type 446 ___ Wz W//_/_ _////__ Type 443 Type 430F 00 Type 430 //i I li///F//@l//i//i'B

22 Table 25 CONDITIONS & FINISHES FOR BAR (2) Conditions Surface Finishes 1. Hot worked only (a) Scale not removed (excluding spot conditioning) (b) Rough turned- (c) Pickled or blast cleaned and pickled 2. Annealed or other- (a) Scale not removed (excluding spot condition- wise heat treated ing) (b) Rough turned (c) Pickled or blast cleaned and pickled (d) Cold drawn or cold rolled (e) Centerless ground () Polished 3. Annealed and cold (d) Cold drawn or cold rolled worked to high (e) Centerless ground tensile strength- (f) Polished

'Surface finishes (b), (e) and (f) are applicable to round bars only. -Bars of the 4xx series stainless steels which are highly hardenable, such as Types 414, 420, 420F, 431, 440A, 440B and 440C, are annealed before rough turning. Other hardenable grades, such as Types 403,410. 41 6 and 41 6Se. may also require annealing depending on their composition and size. '''Produced in Types 302, 303Se, 304 and 316.

Table 26 CONDITIONS & FINISHES FOR PLATE (2) Condition and Finish Description and Remarks Hot rolled Scale not removed. Not heat treated. Plates not recommended for final use in this condition.*

Hot rolled, annealed Scale not removed. Use of plates in this con- or heat treated dition is generally confined to heat resisting applications. Scale impairs corrosion resistance.*

Hot rolled, annealed or Condition and finish commonly preferred for heat treated, blast corrosion resisting and most heat resisting cleaned or pickled applications.

Hot rolled, annealed, Smoother finish for specialized applications. descaled and temper passed

Hot rolled, annealed, Smooth finish with greater freedom from descaled cold rolled, surface imperfections than the above. annealed, descaled, optionally temper passed

Hot rolled, annealed or Polished finishes: refer to Table 24. heat treated, surface cleaned and polished

'Surface inspection is not practicable on plates which have not been pickled or otherwise descaled.

23 Table 27 RELATIVE FORMING CHARACTERISTICS OF AISI 200 AND 300 SERIES (2) (Not Hardenable by Heat Treatment) Forming 303, 347, Method 201 202 301 302 302B 303Se 304 304L 305 308 309 309S 310 310S 314 316 316L 317 321 348 384 Blanking B B B B B B B B B B B B B B B B B B B B B Brake forming B A B A B 0 A A A B A A A A A A A A A A B Coining B-C B B-C B C C-D B B A-B D B B B B B B B B B B A Deep drawing A-B A A-B A B-C D A A B D B B B B B-C B B B B B B Embossing B-C B B-C B B-C C B B A-B D B B B B B-C B B B B B A-B cog' C B C B B D B B A-B D B-C B-C B B B-C B B B B B A For'ging, hot B B B B B B-C B B B B B-C B-C B-C B-C B-C B B B-C B B B Heading. cold C-D C C-D C D D-C C C B-A D C C C C C-D C C C C C A Heading, hot B B B B B C B B B B C C C C C B B B-C C-B C-B B Punching C B C B B B B B B - B B B B B B B B B B B Roll forming B A B A - D A A A - B B A A B A A B B B A Sawing C C C C C B C C C C C C C C C C C C C C C Spinning C-D B-C C-D B-C C D B B A D C C B B C B B B-C B-C B-C A

A = Excellent B =Good C =Fair D = Not generally recommended Note: Ratings are for making comparisons of alloys within their own metallurgical group. They should not be used to compare 300 Series with 400 Series types.

Table 28 RELATIVE FORMING CHARACTERISTICS OF AISI 400 SERIES (2) FERRITIC MARTENSITIC (Not Hardenable by Heat Treatment) (Hardenable by Heat Treatment) Forming 430F, 416, Method 430 430FSe 405 429 434 436 442 446 410 403 414 416Se 420 420F 431 440A 440B 440C Blanking A B A A A A A A A A A B B B C-D B-C - - Brake forming A' B-C A' A* A' A' A' A* A* A' A' C, C C C C Coining A C-D A A A A B B A A B D C-D C-D C-D D D D Deep drawing A-B D A A-B B B B B-C A A B D C-D C-D C-D C-D - - Embossing A C A A A A B B A A C C C C C-D C D D Forging, cold B D B B B B B-C C B B C D C-D C-D C-D C-D D D Forging, hot B C B B B B B-C B-C B B B C B B B B B B Hardening by cold work, typical tensile strength (1000 psi)

Annealed 73 75 - ______90 90 - 70 - -- __ _

25% reduction 96 95 ___- - - 120 120 - 90 -__ ___ - 0 50 /0reduction 115 110 ___- - - 130 130 - 105 -__ ___ - Hardening by heat treatment No No No No No No No No Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Heading, cold A D A A A A B C A A D D C C C-D C C-D C-D Heading, hot B C B B B B B-C B-C B B B C B B B B B B

Punching A-B A-B A-B A-B A-B A A-B B A-B A-B B A-B B-C B-C C-D - _ __

Rollitorming A D A A A A A B A A C D C-D C-D C-D C-D - Sawing B A-B B B B B B-C B-C B B C B C C C C C C Spinning A D A A A-B A-B B-C C A A C D D D D D D D A = Excellent B = Good C = Fair D = Not generally recommended *Severe sharp bends should be avoided

24 Structural uniformity. Forgings are tics of the austenitic stainless steels and sound, nonporous, and uniform in metal- Table 28 shows the relative fabrication lurgical structure. The booklet, "Stainless characteristics of the martensitic and fer- Steel Forgings," available from the Spe- ritic grades. cialty Steel Industry of North America, discusses in greater detail the forgability Sheet, Strip and Plate of stainless steels, and it provides guide- The bending characteristics of lines for designing stainless forgings. annealed austenitic stainless steels, as indicated by Table 29, are considered COLD FORMING excellent. Many types will withstand a The mechanical properties of stainless free bend of 180 degrees with a radius steels serve as an indication of their rela- equal to one-half the material thickness or tive formability at ambient or room tem- less. In a controlled V-block, the bend perature. Annealed austenitic grades are angle limit is 135 degrees. As the hard- typified as having low yield strengths, ness of the stainless increases, bending high tensile strengths, and high elonga- becomes more restrictive. This is indi- tions. Some of these alloys work harden cated by the data in Table 30 which show, to a high degree, which further increases for example, the free-bend characteristics their strength properties. The ferritic of Type 301 in the 1/4-, 1V2-,3/4-, and full- alloys have much lower ductility than the hard temper. The bend characteristics of austenitic types and are closer to carbon the 400 Series types, shown in Table 31 steel with respect to mechanical proper- are also good. However, they tend to be ties; and they do not work harden signifi- somewhat less ductile than the 300 cantly during cold forming. Series types, so the minimum bend Because of their excellent mechanical radius is equal to the material thickness. properties, stainless steels have excellent cold-forming characteristics. Table 27 shows the relative fabrication characteris-

Table 29 BENDING CHARACTERISTICS: Annealed Stainless Steel Sheet & Strip (2) Type Free Bend V-Block 301.302, 304, 305, 309, 180 R=1/2T 135- R=12T A unique feature of forgings is that the continuous grain flow follows the contour 310,316,321,347 of the part, as illustrated by the top draw- NOTE: R=radius of bend; T=thickness of material. All bends are parallel to ing in Exhibit 5. In comparison is the ran- direction of rolling. dom grain structure of a cast part (center) and the straight-line orientation of grain in a machined part (bottom). From this Table 30 difference stem secondary advantages BENDING CHARACTERISTICS: Temper Rolled Stainless Steel Sheet & inherent in forged stainless steels as Strip (2) follows: Type Temper Gage 0.050 in. Gage 0.051 in.- Strength where needed. Through (1.27 mm) and under 0.187 in. grain refinement and flow, forging puts Free Bend (1.30-4.75 mm) the strength where it's needed most. Lighter weight. Higher strength-to- 301 1/4 hard 180 R= 1/2T 90R=T weight ratio permits the use of thinner, 301 1/2 hard 180°R=T 90oR=T light weight sections without sacrificing 301 3/4 hard 180°R=1'/2T safety. 301 full hard 180°R=2T Improved mechanical properties. 302 1/4 hard 180° R= 1/2T 90R=T Forging develops the full impact resis- 316 1/4 hard 180R=T 90'R=T tance, fatigue resistance, ductility, creep- V-Block rupture life, and other mechanical properties of stainless steels. 301 1/4 hard 135R=T 135R-= 1/2T Repeatable dimensions. Tolerances 301 1/2hard 135sR=2T 135R=2T of a few thousandths are routinely main- 301 3/4 hard 135° R=3T tained from part to part, simplifying final 301 full hard 135- R=3T fixturing and machining requirements. 302 1/4 hard 135 R = 2T 135R=2T 316 1/4 hard 135°R=21/2T 135 R=3T

NOTE: R=radius of bend; T=thickness of material. All bends are parallel to direction of rolling.

25 truss square shoulder bolt warm-headed Table 31 in Type 384. Typical Bending Characteristics of Annealed Stainless Steel Sheet, Strip and Plate (2) Both Types 305 and 384 are subject to carbide precipitation if heated or cooled Gage to 0.374" Gage 0.375" to 0.500" slowly in the range of 800-1650F (427- AISI (9.50 mm) (9.53-12.7mm) 899C). This can lead to intergranular cor- Type Free Bend V-Block Free Bend V-Block rosion in aggressive environments. This 405 180'R=T 135-R=T 180'R=T 1350R=2T condition can be corrected, however, by 410 180-R=T 135eR=T 180'R=T 135°R=2T annealing and water quenching from at 430 180'R=T 135-R=T 180'R=T 135°R=2T least 1900F (1038C). Type 302H0 is one 442 180'R=T 135-R=T 180'R=2T 135"R=2T of the most widely used cold-heading 446 180-R=T 135-R=T 180'R= 2T 135-R=2T stainless steels. Its composition is similar to that of Type 304 except that it contains 3.00-4.00% copper. This eliminates NOTE: R=radius of bend; T=thickness of material. All bends are parallel to cracking, especially in recessed heads, direction of rolling. and results in improved tool performance. It becomes mildly magnetic after servere cold working. In simple bending operations, there is more pronounced with increasing chro- little need to consider variations of the mium content. To offset this factor, moder- The three types just described are the general-purpose alloys, since all stainless ate warming of the higher chromium principal stainless steels used for cold- steels within a metallurgical group tend to types is often recommended prior to heading operations. However, many other behave in a similar manner. However, in drawing. stainless steel types are available as cold- the more complex forming operations in heading wire. They include Types 410, which the metal is pressed, drawn, or Bar and Wire 430, 440C, (UNS) S17400 (a precipitation stretched, considerable latitude exists for Many components of stainless steel hardening type) and several proprietary alloy selection. This can be visualized are made from bar or wire with cold stainless alloys. somewhat when one considers the need heading being the most widely used It is well to keep in mind that the inher- for extensive work hardening when a part forming method. Many types of stainless ent high strength of stainless steels is made essentially by stretching. are available as cold heading wire. However, for multiple-blow operations requires more power in forming than that All of the 300 Series alloys work harden for forming carbon steel. And since many considerably and can be stretched in which a number of forming steps are of the alloys work harden rapidly in cold- severely, but this property is exemplified performed in rapid sequence, it is desir- forming operations, there is need for by Type 301. During stretching, hold- able to use a material with good ductility but with a low work-hardening rate. added power after the start of initial down pressures are applied to the flange deformation. The booklet, "Cold Forming areas to prevent metal from flowing into Three stainless steels predominate in this Stainless Steel Bar and Wire," which is the die. During this stretch, severe metal respect; Types 305, 384, and 302HQ. These three are available from the Specialty Steel Industry thinning occurs. However, as the metal similar to Type 304 in of North America, describes in greater thins it work hardens sufficiently to terms of corrosion resistance and depth the selection of materials and the exceed the strength in the thicker (less mechanical properties. design of products to be fabricated by strong) sections, thus preventing cracking With a chromium-nickel ratio less than cold forming methods. or tearing. A good example of stretching that of Type 304, Type 305 has less ten- and the need for Type 301 is the dency to work harden. Accordingly, a manufacture of automobile wheel-covers. greater amount of deformation is possible At the other extreme is Type 305 with a before annealing is necessary. It is also low work-hardening rate that prevents readily available as bar and wire for cold excessive strengthening. It has good heading, cold extrusion, and other cold- ductility and is an excellent choice for forming processes. In terms of corrosion deep drawing in which little hold-down resistance, it is freely interchangeable pressure is used. The use of this material with Type 304. Type 305 resists attack by can minimize annealing for multiple nitric acid and is used in a wide range of draws. organic and inorganic chemicals, food- Between Types 301 and 305 is Type stuffs, and sterilizing solutions. It also has 304, which is the preferred choice when good high-temperature scaling resis- the forming operation combines both tance, and is utilized for continuous serv- drawing and stretching. ice at 1600F (871C). Unlike Type 304, The ferritic stainless steels do not however, Type 305 remains nonmagnetic exhibit nearly as high ductility as the even after severe cold work. austenitic types, nor do they have signifi- Type 384 is widely used for fasteners, cant work-hardening traits. Their formabil- cold-headed bolts, screws, upset nuts, Exhibit 6 ity is thus more like that of carbon steel in and instrument parts, also for severe A warm-headed truss square shoulder that they cannot be stretched without coining, extrusion, and swaging. It is also bott of Type 384 stainless. By using warm thinning and fracturing - and formability ideally suited for thread rolling. Because heading, less forming pressure was re- usually decreases with increasing chro- Type 384 is similar in chromium content quired on the die resulting in increased mium content. In addition, these grades to Type 304, it generally can be used tool life. can show brittle tendencies that become anywhere that Type 304 is used. Exhibit 6

26 Exhibit 7 Exhibit 8 Comparative Machinability of Comparative Machinability of Common Metals Frequently Used Stainless Steels and Their Free-Machining Counterparts

Ratings in 0 AISI TYPDE 0 10 20 30 40 50 60 70 80 90 100 00 50 100 150 200 I I I I !I _ l I I I I 304 I I I I i 303 & M .! Ferritic Stainless Steels 303 Se , , , I'' ...... Martensitic Stainless Steels 430

I...... Austenitic Stainless Steels 430F & 430F Se I ...... Free-Machining Steel 410

...... Carbon Steel 416 & \ e \ \ 416 Se 7 1 . Alloy Steel 420 I I I 1 1 ...... Cast Iron 420F ....-...-.-.-.-.-. Tool Steel 0 10 20 30 40 50 60 70 80 90 100 ...... Hgh-Temperaturei Alloys Ratings in CO D 1Average Maximum I I Source ,\X1 Indicates highest rating National Screw Machine available using High Speed Products Association Steel Tools with suitable 1o based on 10000 for AISI Type 41' 6 cutting fluid. free-machining Stainless Steel. Steel Industry Sources

00 50 100 150 200 It has been traditional in machining literature to compare the machinability of various metals to AISIB-1 112which is a free-machining carbon 10000 Type 416 Stainless Steel steel. However, since Type 416 stainless steel has a machining rating equal to that of B-1112, and since B-i 112 is no longer on the market, comparisons in this booklet will be made with Type 416 as the base at 100%.

MACHINING and get maximum machining produc- improvement in machinability in the free- The machining characteristics of stain- tivity. Here are three suggestions: (1) machining stainless steels - namely less steels are substantially different from specify a free-machining stainless steel, Types 303, 303 Se, 430F, 430F Se, 416, those of carbon or alloy steels and other (2) suggest to the production engineer 416 Se, and 420F - is clearly evident in metals, as illustrated in Exhibit 7, "Com- that he use a special analysis stainless Exhibit 8, "Comparative Machinability of parative Machinability of Common steel that is "more suited for machining," Frequently Used Stainless Steels." (Also, Metals." In varying degree, most stainless or (3) specify stainless steel bar for excellent are several proprietary free- steels without composition modification machining that is in a slightly hardened machining alloys.) are tough, rather gummy, and they tend condition. Suppose, for example, that Type 304 is to seize and gall. being considered on the basis of corro- While the 400 Series stainless steels Free-Machining Stainless Steels sion resistance and strength, but the are the easiest to machine, a stringy chip Some stainless steel compositions con- machine shop needs the best possible produced during the machining, can tain sulfur, selenium, lead, copper, alumi- machining rate. Type 303 could be speci- slow productivity. The 200 and 300 num, or phosphorus - either separately fied as an alternate, provided its proper- Series, on the other hand, have the most or in combination - in sufficient quantity ties meet end-use requirements and 304 difficult machining characteristics, primar- to improve the machining characteristics is not specifically requested. The chro- ily because of their propensity to work of the metal. These alloying elements mium, nickel, and sulfur contents of Type harden at a very rapid rate. reduce the friction between the work- 303 are slightly different than those of An experienced machine shop produc- piece and the tool, thereby minimizing Type 304, and as a result Type 303 can tion engineer can work around these the tendency of the chip to weld to the be machined at speeds about 25-30% conditions and achieve good productivity tool. Also, sulfur and selenium form inclu- faster than Type 304. with any of the stainless steels. However, sions that reduce the friction forces and Type 303 Se is another free-machining wherever conditions permit, the design transverse ductility of the chips, causing stainless steel similar to Type 303 except engineer can help minimize problems them to break off more readily. The that it contains selenium as the ingredient

27 to enhance the machining characteristics. Screw Machining Operations bars or other cooling techniques to dissi- It is used for better surface finishes or Automatic screw machining is a fast pate heat, and proper joint design. The when cold working may be involved, and efficient method for machining that first three methods fall in the realm of such as staking, swaging, spinning, or benefits greatly from the use of the free- welding shop procedures that are often severe thread rolling, in addition to machining stainless steels. In many typi- adequately covered by AWS recom- machining. cal screw machine applications, parts are mended practices and welding shop If end-use conditions call for Type 430 turned out at rates as high as 300 to 400 standard practices. It is always good stainless, the designer can specify free- pieces per hour. However, one should not policy, however, for designers to double machining Types 430F or 430F Se, which have any misgivings about screw check to see that the welding shop fol- have similar properties although less cor- machining any of the stainless steels. lows proper procedures. Also, it is often rosion resistance. Type 430F contains With appropriate design and good shop desirable to provide specimen welds for more sulfur, while 430F Se contains practices, even the non free-machining establishing quality. These precautions selenium instead of a high sulfur content. types can be handled at relatively high are important because corrosion prob- The free-machining choices in lieu of rates. The machinability of stainless steels lems often begin in weld areas. One Type 410 are Types 416 (higher sulfur) or in general has improved significantly in problem, discussed earlier, is carbide 416 Se (selenium). And for Type 420, the the past few years, primarily through precipitation (sensitization) that can lead shop might consider Type 420F. melting and refining practices that permit to intergranular corrosion in corrosive It should be understood that the alloy- tighter analysis control. environments. The lack of proper heat ing elements used to improve the free- dissipation can also lead to heat distortion of the finished product that can be machining characteristics of stainaess JOINING steels can adversely affect corrosion unacceptable for aesthetic reasons. transverse ductility, and other Welding From the designer's viewpoint, joint resistance, Nearly all of the stainless steels can be qualities, such as weldability. These configuration can also encourage heat welded by most methods employed by dissipation. For this reason, the use of grades should be used only after careful differences used, they will industry today. Because of beveled joints is common in thinner consideration, but when carbon or low- produc- between these alloys and gages, which in carbon steel might be machine at significantly higher however, there are variations tion rates. alloy steels, welded as a square-edge butt. Beveling in welding techniques. First, it is impor- permits the use of several light passes, be followed to pre- Special Analysis Stainless Steels tant that procedures thus avoiding the high temperature that serve corrosion resistance in the weld would be reached in a single, heavy If, for example, end-use conditions are adjacent to the use of Type and in the area immediately pass. too restrictive to permit the weld, referred to as the heat- instead of Type 304, designers might Cleaning of the edges to be welded is 303 affected-zone (HAZ). Second, it is desir- suggest using Type 304 with a special also important. Contamination from able to maintain optimum mechanical grease and oil can lead to carburization analysis that has somewhat better certain little properties in the joint, and, third, in the weld area with subsequent reduc- machining qualities but with very prob- resistance. In melt- steps are necessary to minimize tion of corrosion resistance. Post weld difference in corrosion lems of heat distortion. The principal dif- ing of special analysis stainless steels, clean-up is also important and should in the com- ference between stainless and other not be done with carbon steel files and minor modifications are made which pro- certain characteris- steel types is alloy content, brushes. Carbon steel cleaning tools, as position to enhance corrosion resistance. In welding, it metal. A stainless steel vides well as grinding wheels that are used on tics of the is necessary to select a weld rod that producer should be consulted. carbon steel, can leave fine iron particles provides weld filler metal having corro- imbedded in the stainless steel surface identi- Hardened Stainless Steel Bar sion resistant properties as nearly that will later rust and stain if not cal to the base metal as possible or bet- removed by chemical or mechanical When conditions require maximum as obvious as to corrosion in the alloy ter. That is not always cleaning. resistance might expect. For instance, Type selected, and there is no room for com- some stain- 308 is specified for welding Type 304, Martensitic Stainless Steels promise in the composition of the for joining the machine shop can order and 300 Series is often used the possibility of metal- less steel, best suggestion is There is always in a slightly hardened condition 400 Series types. The during cooling, which bar stock American Welding Society lurgical change may result in a small improvement in to follow can lead to cracking. This can be offset that practices for weld metal selection machinability. Under any circumstances, (AWS) by preheating and postheating to reduce environ- (and weld procedures as well) or to con- welds can and especially when corrosive manufactur- the cooling rate. Filler metal for it is always good sult welding consumables identical to the base metal or it can be ments are involved, up-to-date tables for be practice to consult with a stainless steel ers. The latter have an austenitic stainless steel composition. selection. Proper weld filler metal selec- producer. tion not only insures preservation of the corrosion resistant properties, but it is also important in achieving optimum mechanical properties. Another principal difference between stainless and carbon or low-alloy steels is thermal conductivity, with austenitic stainless about half that of other steels. Hence, heat is not dissipated as rapidly.

28 Ferritic Stainless Steels Brazing sion when a galvanic couple is estab- The three major difficulties associated All stainless steels can be brazed, but lished. But the extent of this galvanic with welding ferritic stainless steels are (1) because the brazing alloys are usually action depends on the relative surface excessive grain growth, (2)sensitization, composed of copper, silver, and zinc, area of each material. For instance, if and (3) lack of ductility. Heat treating after high temperatures are required. Care small steel fasteners, such as rivets, are welding can minimize some of these must be taken that the brazing cycle does used to join stainless steel plates, and the problems, or one of the proprietary ferritic not cause such high-temperature prob- assembly is exposed to water, the steel alloys with lower carbon and nitrogen lems as carbide precipitation and a les- rivets will corrode quickly. If, on the other contents can be specified. Filler metal sening of corrosion resistance. hand, stainless rivets are used to join can be of either a similar composition or steel plates in water, both rivets and an austenitic composition (Types 308, Fastening plates will suffer negligible galvanic 309, 316L, or 310), which is helpful in Although fasteners are available in attack, even in the immediate vicinity of improving ductility and toughness. many materials, stainless fasteners are a the rivets. Aircraft designers, for instance, good first choice, especially if the who specify stainless steel fasteners in Austenitic Stainless Steels materials being joined are stainless. aluminum structures depend upon this The 200 and 300 Series are the most Stainless fasteners are easy to make, in area-relationship principle. weldable of the stainless steels. The prob- both standard and special designs, and When the designer has determined lems that arise relate mainly to sensitiza- they are readily available. candidate fastener materials on the basis tion in the heat-affected-zone, which can Since corrosion resistance is an impor- of their corrosion-resistant properties, his be minimized by using the low-carbon or tant aspect of product reliability, inherent next concern probably will be the stabilized grades. in any attempt to prevent corrosion isthe mechanical and physical properties of Preheating is not required; post- careful selection of fastener materials. A these materials. Once again, the group of heating is necessary only to redissolve common practice in industry isto use stainless steels covers a wide choice. The precipitated carbides and to stress relieve fasteners made of metals or alloys that choice need not be difficult if the components that are to be used in are equal to or more corrosion resistant designer uses the guidelines available to environments that may cause stress than the materials they join. This practice him, such as the specifications published corrosion cracking. is justified because the fasteners may by the Industrial Fasteners Institute (IFI). The coefficient of expansion of have to withstand higher loads with Data on stainless steel fasteners are austenitic types is higher than that of car- greater unit stress than the parts being available from the Specialty Steel Indus- bon steels; hence thermal contraction is held together, and they are usually con- try of North America in the booklet, greater. Precautions are necessary to siderably smaller in surface area than the "Stainless Steel Fasteners, A Systematic avoid bead cracking and minimize distor- material being joined. Also, corrosion- Approach to Their Selection." tion, such as sound fixtures, tack weld- weakened fasteners may lead to a more ing, skip welding, copper chill bars, immediate failure with more serious con- minimum heat input, and small weld sequences than the same amount of cor- passes. rosive attack elsewhere in the assembly. Corrosion protection for a fastened joint Precipitation Hardening Stainless encompasses much more than a con- Steels sideration of the corrosion resistance of The precipitation hardening grades are the fastener itself. Required is an analysis suited to welding with little need for pre- of the entire assembled joint as a system. or post-heat treatment except to restore This system includes structural design, or improve mechanical properties. material stresses, product life expectancy and environmental conditions. Free-Machining Stainless Steels Where two dissimilar metals are in con- Problems of porosity and segregation tact in the presence of an electrolyte, a arise when free-machining types are battery effect is created, current flows, welded. However, special filler rods (Type and one of the metals corrodes. In con- 312) are available that, with careful exclu- sidering a bimetallic couple, it is impor- sion of hydrogen from the weld, will assist tant to know which of the two metals is welding. more anodic (less noble). A guide to this is the arrangement of metals in the gal- Soldering vanic series chart shown in Exhibit 9. Any Stainless steels are readily soldered metal in this series will tend to have corro- with relatively few problems arising from sion accelerated when it is coupled, in temperature. Aggressive fluxes, however, the presence of an electrolyte, with a are necessary to prepare the surface for metal in a lower position on the chart. soldering. Phosphoric acid type fluxes The corrosion of this lower metal will tend are preferred because they are not corro- to be reduced, or even avoided. sive at room temperature. A very important factor to consider in evaluating the potential for galvanic corrosion isthe relative surface area of the two different metals in contact. For example, carbon steel is located above stainless steel in the galvanic series and is accordingly subject to accelerated corro-

29 Exhibit 9 Galvanic Series of Metals and Alloys in Sea Water (14)

Magnesium Anodic Zinc More Likely to Be Alclad 3003 Attacked Aluminum 3003 t Aluminum 6061 Aluminum 6063 Aluminum 5052 Mild Steel Low Alloy Steel Cast Iron Stainless Steels (Active) Muntz Metal Yellow Brass Red Brass Copper Aluminum Bronze Silver Stainless Type 430 (Passive) Stainless Type 304 (Passive) Stainless Type 316 (Passive) Monel More Noble Gold Cathodic I

SURFACE PROTECTION AND When stainless cannot be protected by eign particles can burn into the steel sur- CLEANING covering, procedures should be face during heating, which can increase Stainless steels must have clean sur- employed to keep the material clean. the cost of final cleaning or, in extreme faces to offer optimum corrosion resis- Rusty water drips, dirt from overhead cases, render the parts unusable, if tance. Design engineers should take cranes, unclean handling equipment, appearance is a vital factor. steps to see that fabricators either protect even dust from open doors, can be When stainless steels are heated for the metal surface from contamination sources of staining. Perhaps the most forging, annealing, or hardening, an oxi- during forming or other manufacturing severe problems arise in shops that work dized scale forms on the surface. If not steps or restore the surface by mechani- on carbon steel as well as stainless. removed, the scale lowers corrosion cal or chemical cleaning. Using grinding tools on stainless that resistance and can interfere with subse- Metal particles from steel dies can be- were previously used on carbon steel can quent operations. Scale can be removed come imbedded in the surface of the leave particles on the stainless surface mechanically by glass bead blasting or stainless at pressure points. This pickup that will later rust and stain. In such tumbling, or by chemical pickling. The will rust and stain the surface when cases, the best procedure is to chemi- type or degree of scaling determines the exposed to moisture. Chromium plated cally clean the stainless after fabrication, method of cleaning. Frequently, both dies, or a paper or plastic protective in solutions that will dissolve the carbon glass bead blasting and chemical clear- covering on the stainless steel being steel particles, such as solutions of nitric ing are used. Composition of pickling formed, can prevent such problems dur- acid and water. baths vary widely so fabricators are ing many fabrication steps, except for the From a practical standpoint, the com- encouraged to seek advice from stainless more severe operations, such as forging, position of the cleaning bath is not impor- steel producers. machining, heading, coining, drawing, tant as long as it serves the function of Note: ASTM A 380 and A 967 are welding, or spinning. chemically cleaning the surface without good references on cleaning procedures In the case of protective coverings, a harm or discoloration. Procedures and and surface treatments for stainless number of materials are available. Such makeup of solutions are widely published steel. coverings should be selected on the or are available from companies listed on basis of their ability to remain intact dur- the back cover of this booklet. ing layout and fabrication, and on the It is also important to see that stainless basis of their ability to be removed components are thoroughly clean prior to readily. heat treatment. Lubricants, grease, or for-

30 APPENDIX A CORROSION CHARACTERISTICS Pitting occurs when the protective centration of chlorides, are particularly film breaks down in small isolated spots, aggressive with respect to initiating such as when halide salts contact the stress corrosion cracking. While the Other Corrosion Mechanisms should surface. Once started, the attack may mechanism of stress corrosion cracking be considered when using stainless accelerate because of differences in is not fully understood, laboratory tests steels, such as corrosion fatigue, electric potential between the large area and service experience have resulted in delayed brittle fracture and hydrogen of passive surface vs. the active pit. methods to minimize the problem. For stress cracking. Corrosion fatigue is Pitting is avoided in many environ- instance, 2205 (a duplex stainless con- encountered in cyclic loading in a corro- ments by using Types 316 and 317, taining 21-23% chromium, 4.5-6.5% sive environment. Brittle fracture is which contain molybdenum. The four nickel, and 2.5-3.5% molybdenum plus caused by hydrogen impregnation of an alloys in Table I, plus Type 317, per- nitrogen) exhibits superior resistance to alloy during processing, which leads to formed well in desalination environ- chloride stress corrosion cracking; plus it brittle failure when subsequently loaded. ments during a three-year test has a general corrosion and pitting resis- Hydrogen stress cracking results from a conducted by the Committee of Stain- tance superior to Type 317. Studies by cathodic reaction in service. less Steel Producers in Freeport, Texas. Climax Molybdenum Company indicate The austenitic stainless steels resist that Type 317 with 3.5% (minimum) hydrogen effects, but martensitic and molybdenum has good resistance, and it precipitation-hardening alloys may be Table I has been shown to perform well in a flue- susceptible to both hydrogen stress ALLOY UNS gas desulfurization environment. Several cracking and chloride stress-corrosion cracking. Alloy 6X (20Cr-23Ni-6Mo) N08366 proprietary austenitic stainless steels also have shown resistance to stress Sulfide ions, selenium, phosphorus Alloy 216 (19.75Cr-6Ni-8.25Mn cracking in hot chloride environments. and arsenic compounds increase the - 2.5Mo-0.37N) S21600 The ferritic stainless steels, such as propensity for hydrogen to enter Nitronic 50 Types 405 and 430, should also be con- hardenable stainless steels and cause (22Cr-13Ni-5Mn-2.25Mo) S20910 sidered when the potential exists for hydrogen stress cracking. Their pres- Registered Trademark ot Armco Steel Corporation stress-corrosion cracking. ence should warn of a failure possibility. Alloy 2OCb-3- The corrosion resistance of ferritic Cathodic protection can also cause (20Cr-33Ni-2.5Mo-3.5Cu) N08020 stainless steels is improved by increased hydrogen stress cracking of high- e Registered Trademark ot Carpenter Technology chromium and molybdenum contents, strength alloys in service, if "over- while ductility, toughness, and weldabil- protected." Therefore, cathodic protec- Crevice Corrosion results from local ity are improved by reducing carbon and tion, or coupling hardenable stainless differences in oxygen concentration nitrogen contents. The commercialization steels to less-noble materials in corro- associated with deposits on the metal of new melting and refining processes sive environments should be used with surface, gaskets, lap joints, or crevices has resulted in several new ferritic stain- caution. under bolt or rivet heads where small less steels with improved characteristics, Excessive exposure of duplex stainless amounts of liquid can collect and which can be classified as follows; those steels to 1300 to 1750F (700 to 955C) become stagnant. The material respon- with about 18% chromium having corro- tends to form intermetallic compounds sible for the formation of a crevice need sion resistance similar to Type 304, and such as sigma phase or chi phase. These not be metallic. Wood, plastics, rubber, those with more than 18% chromium with compounds of iron, chromium, and glass, concrete, asbestos, wax, and liv- resistance to corrosion comparable or molybdenum are highly detrimental to ing organisms have all been reported to superior to Type 316 in many media. corrosion resistance and toughness. calre crevice corrosion. Once attack With two exceptions (439, 444), these begins within the crevice, its progress is ferritic stainless steels are not AISI num- Intergranular Corrosion very rapid, especially in chloride bered grades. Some of these stainless When austenitic stainless steels are environments. For this reason, the stain- steels are listed in Table II. heated or cooled through the tempera- less steels containing molybdenum are The high-chromium ferritic types have ture range of about 800-1650F often used to minimize the problem. resistance to chlorides previously obtain- (427-899C), the chromium along grain Notwithstanding, the best solution to able only in high-nickel and titanium boundaries tends to combine with car- crevice corrosion is a design that alloys. bon to form chromium carbides. Called eliminates crevices. carbide precipitation, or sensitization, the Stress Corrosion Cracking is effect is a depletion of chromium and the caused by the combined effects of ten- lowering of corrosion resistance in areas sile stress and corrosion. Many alloys Table II adjacent to the grain boundary. This is a systems have been known to ALLOY ASTM UNS time temperature dependent phenomenon, as indicated in Figure 4 (See Appen- experience stress corrosion cracking - 18 Cr and Ti 439 S43035 brass in ammonia, carbon steel in dix B). nitrate solutions, titanium in methanol, 18Cr - 2Mo 444 S44400 Sensitization may result from slow cool- aluminum in sea water, and gold in ace- 18Cr - 2Mo + S XM-34 S18200 ing from annealing temperatures, stress- tic acid. Stainless steels are susceptible 26Cr - 1 Mo XM-27 S44625 relieving in the sensitization range, or to stress corrosion cracking in chloride 26Cr - 1 Mo - Ti XM-33 S44626 welding. Due to the longer time at tem- environments. It is necessary for tensile 29 Cr - 4 Mo S44700 perature of annealing or stress-relieving, stress, chlorides and elevated tempera- 29 Cr - 4 Mo - Ti/Cb S44735 it is possible that the entire piece of mate- ture all to be present for stress corrosion 29 Cr - 4Mo - 2 Ni S44800 rial will be sensitized, whereas the shorter cracking to occur. Wet-dry or heat trans- time at temperature characteristic of fer conditions, which promote the con-

31 I

welding can result in sensitization of a (Most of the proprietary ferritic stainless ble conditions are shown in Table IlIl in band, usually 1/8 to 1/4 inch wide, adjacent steels mentioned earlier are stabilized to the column "Intermittent Service." Expan- to but slightly removed from the weld. prevent sensitization during welding.) sion and contraction differences between This region is known as the Heat- Galvanic corrosion is discussed briefly the base metal and the protective film (or Affected-Zone or HAZ. in the section on fasteners, page 29. scale) during heating and cooling cause Intergranular corrosion depends upon cracking and spalling of the protective the magnitude of the sensitization and the HIGH-TEMPERATURE scale. This allows the oxidizing media to aggressiveness of the environment to CORROSION RESISTANCE attack the exposed metal surface. which the sensitized material is exposed. Stainless steels have been widely used The spalling resistance of the austenitic Many environments do not cause inter- for elevated-temperature service, so fun- stainless steels is greatly improved at granular corrosion in sensitized austenitic damental and practical data concerning higher nickel levels, as illustrated in stainless steel. For example, glacial acetic their resistance to corrosion are available. Figure 7. Nickel reduces the thermal acid at room temperature or fresh clean When stainless steels are exposed at expansion differential between alloy and water do not; strong nitric acids do. Car- elevated temperatures, changes can oxide film and thereby reducing stresses bide precipitation and subsequent inter- occur in the nature of the surface film. For at the alloy-oxide interface during cool- granular corrosion in austenitic stainless example, at mildly elevated temperatures ing. Also, Type 446 and the proprietary steels have been thoroughly investigated; in an oxidizing gas, a protective oxide film ferritic chromium-molybdenum stainless the causes are understood and methods is formed. steels have a fairly low coefficient of ther- of prevent on have been devised. These In more aggressive environments, with mal expansion, which tends to enhance methods include: temperatures above 1600F (871C), the spalling resistance. 1. Use of stainless steel in the annealed surface film may break down with sudden A number of proprietary austenitic condition. increase in scaling. Depending on alloy stainless steels that rely on a silicon, alu- 2. Selection of the low-carbon (0.030% content and environment, the film may be minum, or cerium additions for improved maximum) stainless steels for weld fabri- self healing for a period of time followed oxidation resistance are listed in ASTM cation. Low-carbon grades are Types by another breakdown. A 240 and other product specifications. 304L, 316L, and 317L. The less carbon Under extreme conditions of high tem- available to combine with the chromium, perature and corrosion, the surface film Effect of Atmosphere the less likely is carbide precipitation to may not be protective at all. Much attention has been given to the occur. However, the low-carbon grades For these reasons, the following data compatibility of stainless steels with air or may become sensitized at extremely long should serve only as a starting point for oxygen. However, trends in the design of exposures to temperatures in the sensiti- material selection, not as a substitute for steam and other forms of power genera- zation range. service tests. tion have resulted in a growing interest in 3. Selection of a stabilized grade, such oxidation in such environments as carbon as Type 321 (titanium stabilized) or Type Oxidation monoxide, carbon dioxide, and water 347 (columbium stabilized), for service in In nonfluctuating-temperature service, vapor. Exposure to mild conditions in the 800-1650F (427-899C) range. The the oxidation resistance (or scaling resis- these environments leads to the forma- protection obtained with these grades is tance) of stainless steels depends on tion of the protective oxide film described based upon the greater affinity of titanium chromium content, as indicated by the earlier, but when conditions become too and columbium for carbon as compared curve in Figure 5. Steels with less than severe, film breakdown can occur. The to chromium. 18% chromium (ferritic grades primarily) onset of this transition is unpredictable Columbium stabilization is preferred are limited to temperatures below 1500F and sensitive to alloy composition. because its carbides are more readily (816C). Those containing 18-20% chro- Although the reaction mechanisms are retained in welds and it is easier to add in mium are useful to temperatures of 1800F probably similar in air, oxygen, water the steelmaking process. However, the (982C), while adequate resistance to vapor, and carbon dioxide, reaction rates use of columbium stabilized steel scaling at temperatures up to 2000F may vary considerably. For example, simi- requires additional care in welding. (1093C) requires a chromium content of lar scaling behavior has been observed 4. Redissolving carbides by annealing at least 22%, such as Types 309, 310 or in air and oxygen except that scale break- parts after fabrication, although this is not 446. down occurs more rapidly in oxygen. For always practical. The maximum service temperature this reason, results obtained in air should It should be understood that the above based on a rate of oxidation of 10 mg. be applied with care when considering steps are necessary only if the service per sq. cm. in 1000 hours is given for service in pure oxygen. environment is known to be capable of several stainless steels in Table IlIl for An increase in corrosion rates can be causing intergranular corrosion. nonfluctuating-temperature. The corro- expected in the presence of water vapor. Although sensitization can also occur sion resistance of several stainless steels Figure 8 illustrates the effect of moist air in the ferritic stainless steels (heated to in steam and oxidizing flue gases, com- on the oxidation of Types 302 and 330. 1700F (927C) and water quenched or air pared with their corrosion resistance in Type 302 undergoes rapid corrosion in cooled) it is far less likely to occur than air, is shown in Figure 6. wet air at 2000F (1093C), whereas a pro- with austenitic grades, and intergranular In many processes, isothermal (con- tective film is formed in dry air. The higher corrosion has not been a problem in stant temperature) conditions are not nickel Type 330 is less sensitive to the these steels-except for a narrow band in maintained and process temperatures effects of moisture, so it is assumed that the heat-affected-zone close to welds. vary. The temperature limits under varia- increased chromium and nickel permits

32 higher operating temperatures in moist The oxidation of stainless steels in Hydrogen Sulfide air. Types 309 and 310 are superior at carbon dioxide and carbon dioxide- Low chromium steels are adequate to temperatures greater than 1800F (982C), carbon monoxide atmospheres at resist attack in relatively low hydrogen and Type 446 is usable at temperatures 1100-1800F (593-982C) isof interest sulfide levels, but hydrogen sulfide approaching 2000F (1093C). The addi- because of their use in gas-cooled under high pressure results in rapid cor- tion of moisture to oxygen significantly nuclear reactors. Type 304 is service- rosion. Then a minimum of about 17% increases the corrosion rates of Types able in this environment, although some chromium is required to obtain satisfac- 304, 321, 316 and 347, and for the other proprietary stainless steels offer better tory resistance. Type 304 has been grades listed in Table ll, the temperature resistance. used extensively for this service. The limits should be adjusted downwards. A note of caution about stainless isocorrosion curves shown in Figure 9 steels at high temperatures in stagnant show the effects of hydrogen sulfide oxidizing environments: The protective and temperature on the austenitic stain- film breaks down in the presence of cer- less steels. Table III tain metal oxides, causing accelerated Suggested Maximum attack. For instance, austenitic types are Sulfur Vapor Service Temperatures in Air susceptible to attack in the presence of Sulfur vapor readily attacks the lead oxide at temperatures as low as austenitic grades. In tests, relatively high Intermittent Continuous 1300F (704C). Vanadium oxide, found in corrosion rates were encountered in AISI Service Service 0 fuel ash, may cause failure of Types 309 flowing sulfur vapor at 1060F (571C), Type' 0C F 0C F and 310 at 1900F (1038C) when water although it has been reported that Type 201 815 1500 845 1550 vapor is present. Molybdenum oxide 310 has been successfully used for a 202 815 1500 845 1550 behaves in a similar manner. sulfur vapor line at 900F (482C). 301 840 1550 900 1650 In liquid sulfur, most austenitic grades 302 870 1600 925 1700 Sulfidation are resistant up to 400F (204C), with the Types 321 and 347 showing 304 870 1600 925 1700 Sulfur in various forms and even in stabilized relatively small quantities accelerates satisfactory service to 832F (444C). 308 925 1700 980 1800 corrosion in many environments. Sulfur 309 980 1800 1095 2000 dioxide, hydrogen sulfide, and sulfur 310 1035 1900 1150 2100 vapor are among the most corrosive 316 870 1600 925 1700 forms. Sulfur vapor and hydrogen sul- 317 870 1600 925 1700 fide are considerably more aggressive 321 870 1600 925 1700 than sulfur dioxide. 330 1035 1900 1150 2100 Sulfur attack, although closely related 347 870 1600 925 1700 to oxidation, is more severe. Metal sul- 410 815 1500 705 1300 fides melt at lower temperatures than 416 760 1400 675 1250 comparable oxides, and they may fuse to metal surfaces. Also, sulfides are less 420 735 1350 620 1150 likely to form tenacious, continuous, pro- 440 815 1500 760 1400 tective films. Fusion and lack of adher- 405 815 1500 705 1300 ence result in accelerated corrosion. 430 870 1600 815 1500 The resistance of stainless steels to 442 1035 1900 980 1800 sulfidation depends on chromium 446 1175 2150 1095 2000 content. Sulfur Dioxide Type 316, in a series of 24-hour laboratory tests, was subjected to mixtures of oxygen and sulfur dioxide (vary- It is difficult to indicate maximum serving from 100% oxygen to 100% sulfur ice temperatures for steam service, one dioxide) at temperatures between 10OF reason being the sensitivity of corrosion and 1600F (593 and 871C). Results indi- rate to surface condition. (Cold worked cated that the rate of attack was largely surfaces tend to reduce corrosion effects independent of the gas composition, in steam service.) Most austenitic stain- and no scale developed-only a heavy less steels can be used at temperatures tarnish. up to 1600F (871C), and Types 309, 310, and 446 at higher temperatures. Types 304, 321, and 347 are being used in low- pressure steam systems at temperatures approaching 1400F (760C). Scale on Types 304, 347, and 316 tends to exfoliate at higher temperatures.

33 Flue Gas Table IV The corrosivity of flue gas containing CORROSION RATES OF STAINLESS STEELS IN FLUE GASES sulfur dioxide or hydrogen sulfide is (EXPOSURE 3 MONTHS) (16) similar to that of most sulfur-bearing Material Corrosion Rate gases. Accordingly, the corrosion resis- AISI Coke Oven Gas Coke Oven Gas Natural Gas tance of stainless steels in flue gas Type (1500 F) (816 C) (1800 F) (982 C) (1500 F) (816 C) environments is improved by increased mpy mmpy mpy mmpy mpy mmpy chromium content, as shown in Figure 430 91 2.31 236t 6.00 12 0.30 10. Table IV indicates the effect of chro- 446(26 Cr) 30 0.76 40 1 02 4 010 mium content on corrosion in various 446(28 Cr) 27 069 14 0.36 3 0.08 fuel sources. Corrosion rates of 1 to 2 mils per year have been reported for 302B 104 2 64 225t 6.00 -- Types 304, 321, 347 and 316 in the tem- 309S 37' 0.94 45 1.14 3 0.08 perature range 1200-1400F (649-760C). 310S 38- 0.97 25 0.64 3 0 08 For reducing flue-gas environments, 314 23- 0.58 94 2.39 3 0.08 satisfactory material selection requires service tests. * Pitted specimens-average pit depth. t Specimens destroyed. Other High-Temperature Environments Data are available on the corrosion resistance of stainless steels in other high-temperature environments, such as their use for liquid-metal environments. Designers are referred to the following publications for additional data on high-temperature applications: Selection of Stainless Steels, ASM Engineering Bookshelf and Corrosion Resistance of the Austenitic Stainless Steels in High-Temperature Environ- ments, by The Nickel Development Instutute.

34 APPENDIX B

Figure Effect of Chromium Content on Corrosion Rate (2)

Mpy mmpy 0.200 8 I 0.175 7

0.150 -6 I c0.125 5_ 0 \ 2 0.100 4 0 L) 0.075 3

0.050 2

0.025 1 I _ _ _ _ _

0 2 4 6 8 10 12 14 16 % Chromium

Figure 2 Effect of Chemical Content on Corrosion Rate (3) Mpy mmpy 500 = _= _/_06 0.7.HF 12.00 -

0.6 400 ______10.00

88.00 300

0.4

2 6.00 0.3

o 200 .00_ ____0. 4.00~~~~~~~~~~~~~~~~~~.

0.1

1000

2 0

2 2.5 3 3.5 4 4.5 5 Sulphuric Acid, %

Small quantities of hydrotluoric and sulfuric acids can have a serious effect on Type 316 stainless in 250o P205 phosphoric acid with 1.5° F as H2SiF6 at 190 F (90 C).

35 Figure 3 Effect of Temperature on Corrosion Rate (4)

93% H2SO4 with Velocity of 0.1 footisecond

mpy Type 304 mpy Type 316 (mmpy) (mpy Tp 1 1000 1 0000 (25.40) (254.0)

1000 ______(25.40) 100 (2.54)

C C o 6 100 6 8 1 20 4 6 80 o ~~~~~~~~~~~~~~0T r(2.54) o 0 U C.)

10 (0.254)

(0.254)

1.,0 1.0 (0.025) (0.025) 100 140 180 220 260 300 340 F 100 140 180 220 260 300 340 F I I II I I I I I I II II 40 60 80 100 120 140 160 180GC 40 60 80 100 120 140 160 1800C Temperature Temperature

36 Figure 4 Effect of Carbon Content on Carbide Precipitation (5)

F C _ _ _ _ _

1600 90C 0.08 0.062 0.06 0.05 05

800 __ __ _ 1400

1200 0.042 0. E 600 n0ni0oo% 1000

800

losec. lmin. 10min. lhr. 10hrs. 100hrs. 1000hrs. 10,000hrn Time-Temperature-Sensitization Curves Time required for formation of carbide precipitation in stainless steels with various carbon contents. Carbide precipitation forms in the areas to the right of the various carbon-content curves. Within time-periods applicable to welding, chromium-nickel stainless steels with 0.05% carbon would be quite free from grain boundary precipitation. (7)

Figure 5 Effect of Chromium Content on Scaling Resistance (At 1800 F or 982 C) (2)

45 -- ll

40 - _ _

35 - (A 0 -'30 -

25-

?-25 _ -_

U ' C,,I

10 12 14 % Chromium

37 Figure 6 Corrosion Rates in Various Gases (7)

Mmpy Steam Flue Gas Z Air

10 (0.254)

Rate Corresponding Allowance of Boiler to Corrosion Power Code

1.0 (0.025)

0.1 (0.003)

304 321 347 316 318 16-25-6 17-14 CuMo Stainless Steel Type

Comparative corrosion rates of stainless steels in steam at 1250 F (677 C), flue gas at 1200 to 1400 F (649 to 760 C). and air at 1400 F (760 C). (Exposure time was 6950 hours for steam and flue gas. 1260 hours for air.)

38 Figure 7 Figure 8 Effect of Nickel (Cr, Cb) on Oxidation of Types 302 and 330 Scaling Resistance (2) in Wet and Dry Air (8) 70 I IF 35

E 60 U r 25

E 20

50 Z 15

40 5

0 -j 0 .2) 0 100 200 300 400 500 3 30 Time, Hr 14

12 20 E 10 onU

0) E 8 10 -

6 ,2) 0 4 0 0 200 400 600 800 1000 Hours of Cycles Scaling resistance of some iron-chromium-nickel alloys in cycling-temperature conditions at 1800 F (982 C). Cycle 0 consisted of 15 min. in the furnace and 5 min. in air. Sheet 0 200 400 600 800 1000 specimens 0.031 in. (0.787 mm) thick were exposed on both sides. Time, Hr

39 Figure 9 Effect of Temperature and H2S on Corrosion Rate (9)

8.0 IlIJ1IT

6.0-

4.0-

2.0 - Lines of Constant Y Corrosion Rate

1.0 - \ >0 0.80

0.60

CF0.40

U 02 W

02 -

4 0.0 600 800 1000 12 1400

L I I I I _ II 200 300 400 500 600 700 C Temperature Effect of temperature and hydrogen sulfide concentration on corrosion rate of chromium-nickel austenitic stainless steels in hydrogen atmospheres at 75 to 500 psig (1.21-3.45 MPa). (Exposure time greater than 150 hr.)

40 10 Figure Figure 1 0 Effect of Chromium in Normal Combustion Atmosphere (10)

C F ax 1200 2200

2000

0 O 1000 -1800 080 0

CD 1600

CD Em 800 E a 1400

E 1200 Normal_ Combustion Atmosphere *E 600

; 600 1000 0 4 8 12 16 20 24 28 Chromium in Steel, % Effect of chromium on the oxidation resistance of steel in a normal combustion atmosphere

Figure 11 Stress Strain Curves for Type 304 and Type 301 (2) MPa ksi 140

120- 800 -

100 C .) 600-

400 60

0 10 20 30 40 50 60 70 Engineering Strain, Percent

41 Figure 12 Figure 14 Effect of Cold Work on Effect of Cold Work on Mechanical Properties Mechanical Properties of Type 202 (2) of Type 305 (2)

MPa ksi

1400 - 200

1200

1000 -

8006 0

us 600 0 If- E 'E a) c 400 a) 20 a) Q 9L it0 C~ .9 0 200 C L 0 0) 0 C C 0 9U 0 LU 0 20 40 60 0 20 40 60 Cold Work, percent Cold Work, percent

Figure 13 Figure 15 Effect of Cold Work on Effect of Cold Work on Mechanical Properties Mechanical Properties of Type 301 (2) of Type 310 (2)

MPa ksi

1400 200

1200b

1 000 _

CS 0) 800f- a

600 _ - C) 400 _ 'a 0 0 I)L . 200 - M 0

0 0 w 0 20 40 60 Cold Work, percent Cold Work, percent

42 Figure 16 Effect of Cold Rolling and Test Direction on Notch Strength of Type 301 Sheet (2) MPa ksi

240 Unnotched 1600-Tesl

= 200 ~~~Strength <7 200- On Em ~~~~~~~~~~~~~~Strength C1200 160

800 120

80 0 20 40 60 80 Reduction, percent

Figure 17 Representative Stress-Strain Curve for Half-Hard Stainless Steel and Mild Steel (2) MPa ksi Stainless Steel 120- -'2 Hard 800 Transverse Compression

Longitudinal Tension 100- - Transverse Tension

Longitudinal Compression 600 80

@ /// / / ~~~~~~~~~~~~~~~029.Offset

w10030 / / ~~~~~~~~~~~~~Yield Strength 400 60--

200STVA3 AS /~~~~~

20-

0 0 11 0 0.002 0.004 0.006 Strain, in/in

43 Figure 18 Figure 19 Izod Impact Values for Type 410 Izod Data for 410 After Quenching Quenched from 1800 F (982 C) and from 1800 F (982 C) and Tempering Tempered for 3 Hours at Indicated at 1150 F (621 C). (Bhn 228) (2) Temperature (2) J ft-lb J ft-lb

- 160 r.120 160 120

100 I 100

120 I- 120 -

80k 80 *0

0 cm .0 80k- 60f- 80 _- 60 Cj C :cJ La C1 a) 40H 40

401- 40 -

20 20

I I I I I I I I I L I OL . . . 0 (I Fv u D00 700 900 1100 1300 F -150 -100 -50 0 -50 100 150 200 250

1 1 1 1 1 1 I i l C 300 500 700 C -100 -50 0 50 100 Tempering Temperature Testing Temperature

Figure 20 Fatigue Data for Quenched-and-Tempered Type 403 (Rockwell C 24 to 26) (2) ksi 100 MPa Tested at Type 403 7 F R, 24to 26 600 - (24 C) 80 SOO00F Xo 400 _60 (260 C)

60- cj400

40-70F

200

0.01 0.1 1 10 100 Millions of Cycles to Failure

44 Figure 21 Hot-Strength Characteristics (2)

MPa ksi

1400 200 - Semiaustenitic Precipitation and ..... \ Transformation- Hardening Steel 1200 1200 _ _ I~~~~~...... \.. ... g 150 - 1000

C- r 800

100 600 -

Martensitic and 400 Ferritic Grades Austenitic Grades 50

200- Low-Carbon Unalloyed Steel

0 a F 0 400 800 1200 1600

C 0 200 400 600 800 Temperature

General comparison of the hot-strength characteristics of austenitic, martensitic and ferritic stainless steels with those of low-carbon unalloyed steel and semi-austenitic precipitation and transformation-hardening steels.

45 Figure 24, 25, 26 Comparative 100,000-hr Stress-Rupture Data for Types 316 and 347 Tube and Pipe and on Type 304 Bar. (2)

MPa ksi 300F _ I Figure 24 I ype 3u4 L 'UI Annealed Bar I

30 w 200 U)

100 10

I I I I I I I I I I 300 Figure 25 40 Type 321 Hot Worked and Annealed

30 200 - La Unexposed U) 0 20 Exposed for 100 - 10,000 hrs. at Test Temperature 10 I

I I I I I I I I I I 300 Figure 26 40 Type 347 Hot Worked and Annealed

u 200 30 0 P,

20 _

100 _

I I I I I I I I F 900 1000 1100 1200 1300 1400 I I I I C 500 600 700 Temperature

48 Figure 27 Effect of Holding 10,000 Hr at 900, 1050 and 1200 F (482, 566, and 649 C) on the Impact Characteristics of Type 410, 430 and 304 (11)

J ft-lb

60 F

40 F-

20 -

CCn c utc} 80 F U C1E 60 - zc C) 40p 0

C) 20 - a. cE co rs

80 -

60 t-

40 -

I I I I II C -150 -100 -50 0 50 100 150 Temperature

Hardness Values Were as Follows DPN Hardness After Exposure for 10,000 hr at 900 F 1050 F 1200 F (482 C) (566 C) (649 C)

410 125 125 124 123 430 185 274 198 169 304 138 140 147 141

49 Figure 28 Linear Thermal Expansion of the Three Main Classes of Stainless Steel IN/FT 0.24 7 / 0.20 - AUSTENITIC 7 GRADES 7 7

-j 0.12

I- < 008

0.04- MARTENSITIC AND FERRITIC GRADES 0l 1 F 0 400 800 1200 1600 2(1000

C 0 200 400 600 800 1000 TEMPERATURE

Figure 29 Factors Affecting Heat Transfer (12)

Steam Side Water Film 18%o

Steam Side Fouling 8`0 Tube Wall 2 o

Water Side Fouling 330o

Water Side Film 39"o

50 Figure 30 Overall Heat Transfer vs. Exposure Time (13)

800 4450

3350 600

IL\

2250 _ mo Type 304 Stainless Steel

1150 200 Arsenical Admiralty

_ ~~~~~ I I ~~ I ~~~II I 100 200 300 400 500 600

Exposure Time-Days

51 REFERENCES 1.Steel Products Manual "Stainless and Heat Resisting Steels' American Iron and Steel Institute, Washington, D.C. 2. Stainless Steel Industry Data. 3. E. Pelitti, "Corrosion: Materials of Construction for Fertilizer Plants and Phosphoric Acid Service:' Chemistry and Technology of Fertilizers, American Chemical Society Monograph Series, Reinhold Publishing Corp. (1960), pp. 576-632. 4. A.O. Fisher, "New Methods of Simulating Corrosive Plant Conditions in the Laboratory' Corrosion 17, (1961), pp. 215t-221t. 5. Svetsaren English Edition 1-2; (1969), pp. 5. 6. G.C. Wood, Corrosion Science, 2 (1962), pp. 173. 7. F.Eberle, F.G. Ely, and J.S. Dillon, "Experimental Superheater for Steam at 2000 psi and 1250F. Progress Report After 12,000 Hours of Operation," Trans- actions ASME, 76 (1954), pp. 665. 8. D. Caplan and M. Cohen, Corrosion, 15 (1959), pp. 141t. 9. E.B. Backensto and J.W. Sjoberg, "Iso-corrosion Rate Curves for High- Temperature Hydrogen - Hydrogen Sulfide," Corrosion, 15 (1959), pp. 125t. 10. T.M. Krebs, Process Industry Corro- sion Notes, Ohio State University, Sep- tember (1960). 11. G.V. Smith, W.B. Seens, H.S. Link and PR. Malenock, "Microstructural Instability of Steels for Elevated Tempera- ture Service," Proceedings ASTM 51 (1951), pp. 895. 12. E.L. Lustenader and FW. Staub, "Development Contribution to Compact Condenser Design 'The International Nickel Company Power Conference, May 1964 (Unpublished). 13. R.A. McAllister, D.H. Eastham, N.A. Dougharty and M. Hollier, "A Study of Scaling and Corrosion in Condenser Tubes Exposed to River Water," Corro- sion, 17 (1961), pp. 579t-588t. 14. "Corrosion in Action," The Interna- tional Nickel Company Inc., New York. 15. "Stainless Steel and the Chemical Industry," Climax Molybdenum Com- pany, 1966, Greenwich, Conn. 16. W.F. White, Materials Protection, 2 (1963), 47. 17. K.G. Brickner, G.A. Ratz, and R.F Dumagala, "Creep-Rupture Properties of Stainless Steels at 1600,1800, and 2000F," Advances in the Technology of Stainless Steels, ASTM STP 369 (1965) 99. 18. Tranter Mfg., Inc.

52 STAINLESS STEEL PRODUCERS SPECIALTY STEEL INDUSTRY OF NORTH AMERICA

Allegheny Ludlum Corporation North American Stainless An Allegheny Teledyne Company 6870 Highway 42 East 1000 Six PPG Place Ghent, KY 41045 Pittsburgh, PA 15222-5479 (502) 347-6000 (412) 394-2800 Precision Specialty Metals, Inc. Allvac 3301 Medford Street An Allegheny Teledyne Company Los Angeles, CA 90063 2020 Ashcraft Avenue (213) 267-3200 P.O. Box 5030 Republic Engineered Steels Monroe, NC 28111 Specialty Steel Products Division (704) 289-4511 or (800) 841-5491 410 Oberlin Road S.W. Armco Inc. Massillon, OH 44647 One Oxford Centre (330) 837-6000 301 Grant Street Rodney Metals Pittsburgh, PA 15219-1415 An Allegheny Teledyne Company (412) 255-9800 1357 E. Rodney French Boulevard Carpenter Technology Corporation New Bedford, MA PO. Box 14662 (508) 996-5691 or (800) 225-8104 Reading, PA 19612-4662 Atlas Specialty Steels (610) 208-2000 Division of Atlas Steels, Inc. Talley Metals Technology, Inc. One Centre Street P.O. Box 2498 PO.Box 1000 Hartsville, SC 29551 Welland, OT L3B 5R7 (803) 335-7540 CANADA G.O. Carlson, Inc. (800) 263-5712 350 Marshallton Road Atlas Stainless Steels RO. Box 526 Division of Atlas Steels, Inc. Thorndale, PA 19372-0526 1640 rue Marie Victorin (610) 384-2800 Tracy, Quebec J3R 4R4 J&L Specialty Steel, Inc. CANADA RO. Box 3373 (514) 746-5000 Pittsburgh, PA 15230-3373 Special Metals Corporation (412) 338-1600 Middle Settlement Road Lukens, Inc. New Hartford, NY 13413 50 South First Avenue (315) 798-2900 Coatesville, PA 19320 Techalloy Company, Inc. (610) 383-2000 370 Franklin Turnpike Mexinox S.A. de C.V. Mahwah, NJ 07430 AV. Industrias 4100 (201) 529-0900 Zona Industrial C.P. 78090 San Luis Potosi, S.L.P. Mexico 011-52-48-26-5139

SPECIALTY STEEL INDUSTRY OF NORTH AMERICA 3050 K Street, N.W. Washington, D.C. 20007 TEL: (202) 342-8630 or (800) 982-0355 FAX: (202) 342-8631 http://www.ssina.com FIPublications l~ Available I [ ~~~~Nickel F ~~~Development Institute

P The material presented in this publication has been prepared for the general information of the reader and should not be used or relied on for specific applications without first securing competent advice. The Nickel Development Institute, its members, staff and consultants do not represent or warrant its suitability for any general or specific use and assume no liability or responsibility of any kind in connection with the information herein. Publications Available from NIDI Nickel Development Institute

Publications covering a wide range of the applications and properties of nickel-containing materials. To order the publication(s) you want, please use the handy reply card provided or contact any Nickel Development Institute office. For other services offered by the Nickel Development Institute visit our website www.nidi.org CONTENTS

Literature listed by catalogue number, and with summaries Section I, publications by Inco ...... 1 Section II, publications by AISI ...... 7 Section III, publications by NiDI ...... 10 Diskettes listed by catalogue number, and with summaries ...... 31 Videos listed by catalogue number, and with summaries ...... 31 Periodicals ...... 31 Index of publications by industry sector or application: ...... 32

Aerospace Cryogenics Petroleum and gas Agriculture Desalination Pollution control Alloy steels Ductile irons Powders Architecture Electrical and electronics Power Automotive Electroplating and Pulp and paper electroforming Cast irons and cast alloys Environmental, health Rail and highway transportation Chemical and process and safety Stainless steels Civil engineering High-nickel alloys High-temperature alloys Welding and fabrication Construction equipment and machinery Iron-nickel alloys Miscellaneous Consumer products Maraging steels Diskettes Copper alloys Marine and shipbuilding Periodicals Corrosion Mining and cement Videos 1

Section I Publications by Inco Publications in this section, carrying catalogue numbers from 0 to 8999, were originally published by Inco Limited prior to 1985. The information was based on extensive research, data and various alloys and grades available at the time of publication.

70 Ni-HARD - ENGINEERING PROPERTIES AND 297 PROPERTIES OF SOME METALS AND ALLOYS APPLICATIONS (16 pages, 1981) (64 pages, 1983) Presents mechanical and physical properties of Types 1, Chemical composition, mechanical properties, physical 2, 3 and 4 Ni-Hard castings. Also discussed are fabrica- properties and specifications of a wide variety of metals tion processes including machining, brazing, welding and alloys are presented in tabular form. These typical and casting details. A large number of industrial applica- data are presented to facilitate general comparison and tions are illustrated. Special attention is paid to mill liner are not intended for specification or design uses. design and grinding ball service in the cement, coal 310 NICKEL AND GREY IRON - INFLUENCE ON pulverizing and mining industries. Illustrates pumps, STRUCTURE AND PROPERTIES (16 pages, 1973) wear plates, roll and liner segments, drop balls and pipes. Reviews published and unpublished data on the influ- 242 MACHINING AND GRINDING Ni-RESIST AND ence of nickel additions, alone and in combination DUCTILE Ni-RESIST (24 pages, 1976) with other alloying elements in grey irons; illustrates Provides general directions for machining Ni-Resist and the reduction in chilling potential, increased ductile Ni-Resist. Includes selection of cutting speeds, hardenability, and response to heat treatment ob- lubricants, tool materials and proper tool grinds. Reports tained. Shows improvement imparted by nickel and machining tests on these two cast metals to determine various alloy combinations on strength, modulus of their relative machinability. Gives recommendations for elasticity, fatigue and hardness. Demonstrates nic- turning, boring, facing, drilling, reaming, grinding, thread- kel's effect on growth at high temperatures, section ing, honing and lapping Ni-Resist and Ni-Resist ductile sensitivity, corrosion resistance, machinability and irons. Includes tables, sketches and photomicrographs. pressure tightness. 266 HEAT-RESISTANT CASTINGS, CORROSION- 313 AUSTENITICCHROMIUM-NICKELSTAINLESSSTEELS RESISTANT CASTINGS, THEIR ENGINEERING AT SUBZERO TEMPERATURES-MECHANICAL AND PROPERTIES AND APPLICATIONS (60pages, 1978) PHYSICAL PROPERTIES (24 pages, 1975) Contains basic information on how to use the heat- Includes tables and graphs showing the properties of the resistant and corrosion-resistant alloy castings. Dis- AISI and ACI standard austenitic stainless steels at sub- cusses compositions, metallurgical structures, high zero temperatures. Data are presented on the tensile, temperature properties, corrosion resistance, fabrica- compression, fatigue, and impactproperties of the wrought tion, physical properties and mechanical properties. steels in the annealed and cold-worked conditions, and of Includes typical applications. cast steels. Includes data on density, thermal, electrical, 278 3%% NICKEL STEEL FOR LOW-TEMPERATURE elastic and magnetic properties. SERVICE (12pages, 1974) 318 CORROSION RESISTANCE OF THE AUSTENITIC Presents mechanical and physical property data on low CHROMIUM-NICKEL STAINLESS STEELS IN carbon 31/2% nickel steel at temperatures down to ATMOSPHERIC ENVIRONMENTS (16 pages, 1983) -1 50'F. Data included are tensile properties, impact prop- A discussion of the corrosion resistance of the AISI stand- erties, fracture toughness, fatigue properties, corrosion ard austenitic stainless steels in rural, industrial, and ma- resistance and welding. Includes normalized and quenched rine atmospheres, with tabular data. Included are brief and tempered conditions and covers ASTM standards. discussions of architectural, structural, transportation and 279 RESISTANCE OF NICKEL AND HIGH-NICKEL hardware applications and the use of stainless steel insect ALLOYS TO CORROSION BY HYDROCHLORIC screens. ACID, HYDROGEN CHLORIDE AND CHLORINE 328 TYPES 304 AND 304L STAINLESS STEELS FOR (32 pages, Prior to 1985) LOW TEMPERATURE SERVICE (6 pages, 1964) Previews of service experience plus numerous labora- Basic data sheet containing mechanical and physical tory and plant corrosion tests on the performance of properties of Types 304 and 304L stainless steels, with nickel and nickel alloys in contact with chlorine, hydro- particular reference to subzero uses and codes governing gen chloride and hydrochloric acid. Discusses organic welding procedures. chlorinations, synthetic resins and rubber, petroleum 337 ALLOY 713C TECHNICAL DATA (20 pages, 1968) refining, and pickling solutions. (4015) 281 CORROSION RESISTANCE OF NICKEL AND Alloy has good castability, remarkable resistance to oxi- NICKEL-CONTAINING ALLOYS IN CAUSTIC SODA dation and thermal fatigue, and outstanding structural AND OTHER ALKALIES (40 pages, 1973) (4442) stability. Presents basic technical information including Describes corrosion resistance and successful uses of composition, physical and mechanical properties, and nickel and high nickel-containing materials in the ship- heat treatment and fabricating data of alloy 713C, a ment, storage and processing of caustic solutions. Notes precipitation hardenable, nickel-chromium base cast al- applications such as the production of caustic soda itself loy, which possesses excellent strength properties up to and its uses in rayon, soap, pulp and paper, and oil l 800°F. refining. 2

352 THE ROLE OF ALLOYS IN ENGINEERING GREY helium. These properties, coupled with good weldability IRON CASTINGS (8 pages, 1973) and desirable physical properties, make it economically Discusses factors that contribute to the production of attractive for many demanding cryogenic applications. high-quality engineering grey iron castings: production Presents the basic mechanical, physical and corrosion of the proper base iron, proper use of alloys, and use of properties of 36% nickel-iron alloy, along with heat good foundry practices. Includes recommendations for treatment and welding data. specifying these castings to assure the attainment of the high quality needed to meet the ever-increasing demands 415 CORROSIONRESISTANCEOFNICKEL-CONTAINING put on cast products. (Reprinted from Foundry). ALLOYS IN PHOSPHORIC ACID (40pages, 1966) (4156) Presents information on the general behaviour of nickel- 375 COPPER-NICKEL ALLOYS FOR FEEDWATER containing alloys in pure phosphoric acid solutions, prin- HEATER SERVICE (12 pages, 1965) cipally under laboratory conditions. Corrosion data are Reviews some of the problems associated with corrosion given for numerous metals and alloys following test expo- and scaling of feedwater heater tubing in the steam sures under actual operating conditions at plants manufac- systems of electrical power stations. An accelerated labo- turing phosphoric acid by both the wet process and the ratory test has been developed to show the susceptibility electric furnace process. Reports test data for the corrosion of copper-nickel alloys to scale exfoliation. A wide range resistance of metals and alloys in plants using phosphoric of copper-nickel alloys, including 90/10, 80/20, 70/30 acid to produce phosphate fertilizers of the solid, liquid and 60/40, were evaluated for potential feedwater heater mixed, granular-mixed, slurry types. Materials of con- service. (Reprinted from Corrosion.) struction have been evaluated for handling pickling and 388 ANNEALED, HOT ROLLED, AND NORMALIZED metal treating solutions, phosphoric acid catalysts, and NICKEL ALLOY STEELS (16 pages, 1967) pH-control applications by the chemical industry. Provides information on the mechanical properties of 428 FABRICATION OF CHROMIUM-NICKEL STAINLESS nickel alloy steels in the unhardened condition used for STEEL (300 SERIES) (40 pages, 1983) fabricating operations. Presents representative tensile Stainless steel can be fabricated by all methods commonly properties of as-rolled, annealed, and normalized nickel- used with other metals. Because of differences in containing steels in graphic form. mechanical and physical properties, slight alterations in 389 ISOTHERMAL TRANSFORMATION DIAGRAMS OF manufacturing techniques may be necessary. Presents NICKEL ALLOY STEELS (44 pages, 1984) methods forcutting, spinning, bending, andpress drawing stainless steels in the Type 300 series. Reviews finishing Presents isothermal transformation diagrams for the stand- operations and welding procedures. ard nickel alloy steels, carbon steels and nonstandard nickel alloy steels. A cooling curve adapter is provided, 439 NICKEL ALLOY STEELS FOR HEAVY FORGINGS offering a convenient means of estimating, from the I-T (30 pages, 1967) diagrams of the steels, the hardness and structures that will Provides information on specifications, properties and com- result from continuous cooling at different constant rates. positions of nickel-alloy steels used for heavy forgings. The 392 HARDENABILITY OF NICKEL ALLOY STEELS data pertain to massive components, usually more than four (56 pages, 1984) inches thick, normally forged or pressed from large ingots in open dies. Alloy steels are used for heavy forgings to Presents hardenability information in three forms : (1) achieve higher strength, better fracture resistance, or im- tables showing the relationships between hardness, tensile provements in other specific properties for a wide properties and section size of quenched and tempered bars; variety of applications .Examples are turbine and generator (2) end-quench hardenability curves; (3) continuous cool- rotors and disks, large axles and shafts, large gears, ship ing transformation diagrams which indicate the progress of forgings, and pressure vessels components. austenite transformation during cooling. 443 CORROSION RESISTANCE OF NICKEL- 393 HIGH-TEMPERATURE HIGH-STRENGTH NICKEL- CONTAINING ALLOYS IN HYDROFLUORIC ACID, BASE ALLOYS (40 pages, 1995) HYDROGEN FLOURIDE AND FLOURINE Reviews the main nickel-base alloys that have outstand- (36pages, 1976) (4155) ing high-temperature strength characteristics. Included Presents the corrosion-resistant characteristics of nickel are cast and wrought nickel-base alloys as well as some and nickel-containing alloys in hydrofluoric acid, cobalt-base and iron-base alloys. Presents information on hydrogen flouride, flourine and some flourine-containing composition, mechanical properties at room and high compounds, information helpful in selecting materials of temperatures, and some physical property data. construction in plants handling these chemicals. 406 NICKEL ALLOY STEEL CASTINGS (24 pages, 1967) Hydrofluoric acid, hydrogen flouride and flourine readily Presents information and data on specifications, composition react with many metals to form metallic flouride films and hardenability, heat treatment and mechanical properties which, in the case of high-nickel alloys, tend to be of most types of cast nickel-containing steels. Also discusses protective to further reactions. This characteristic makes material selection for high- or low-temperature use and wear nickel-containing alloys useful forthe handlingof flourine and abrasion resistance. Includes data on welding. compounds. Reports extensive corrosion data for laboratory and plantexposures, and industrial applications 410 36% NICKEL-IRONALLOY FOR LOWTEMPERATURE of several nickel-containing alloys. SERVICE (8 pages, 1976) 447 ALLOY STEEL COMPOSITIONS (12 pages,1971) 36% nickel-iron alloy possesses a useful combination of low thermal expansion, moderately high strength and Four tables show specified compositions of alloy steels, good toughness down to -4250 F, the temperature of liquid boron alloy steels, H-steels and boron H-steels. 3 472 NICKEL ALLOY TOOL STEELS (20 pages, 1968) 584 WELDING OF MARAGING STEELS (48pages, 1974) Confined largely to a discussion of nickel alloy steels A detailed report of the welding of maraging steels. developed primarily for tool and die purposes, the cutting Discusses the physical metallurgy of maraging steel as it and shaping of other metallic and nonmetallic materials. relates to welding. Also covers properties of welds, filler Provides information on the composition, treatment, prop- wires to be used, recommended welding processes and erties and applications of the nickel alloy tool steels. welding techniques for obtaining maximum properties. 479 NICKEL ALLOY NITRIDING STEELS (Interpretive Report No. 159, Welding Research Council.) (16 pages, 1968) 959 STANDARD FORMS AND FINISHES FOR Nickel alloy steels are nitrided to increase hardness, STAINLESS STEELS (4 pages, 1963) resistance of wear and galling, and to improve fatigue Lists the standard forms and finishes for stainless steels properties. Covered are nickel-containing steels suitable established by the American Iron and Steel Institute. for surface hardening by nitriding with gaseous or liquid Finished forms include plates, sheets, strips, bars, struc- media, and data on the mechanical and metallurgical tural shapes, round and flat wire, and tubing, whereas properties of these nitrided steels. semifinished forms are produced as rods, blooms, bil- 483 IN-100 ALLOY- ENGINEERING PROPERTIES lets, slabs, and tube rounds. The finishes of stainless steel (20 pages, 1968) sheets are indicated by a system of numbers established by AISI. Presents chemical, physical, and mechanical properties for this nickel-base, precipitation hardenable alloy, which 1107 THE DESIGN AND INSTALLATION OF90/10COPPER- possesses high rupture strength through 1900'F. Presents NICKEL SEAWATER PIPING SYSTEMS data in tables and graphs. Includes recommended condi- (16pages, 1973) tions for machining. Discusses problems encountered when upgrading seawater cooling systems from galvanized steel to cop- 497 IN-738 ALLOY - PRELIMINARY DATA (12 pages, 1981) per-nickel. Suggests ways to improve the reliability of current systems and the systems now being built in high- IN-738 is a vacuum-cast, precipitation hardened, nickel- performance cargo vessels and tankers. base alloy possessing excellent high temperature creep rupture strength combined with hot corrosion resistance 1108 NICKEL ALLOY STEEL PLATES (40 pages, 1972) superior to that of many high-strength superalloys of Describes nickel alloy steel compositions used in plate lower chromium content. It provides the gas turbine form for such applications as fired and unfired pressure industry with a cast alloy having good creep strength up vessels, fabricated structural applications, nuclear reactor to 1700 -1800'F combined with the ability to withstand vessels, and equipment for processing, storage, and trans- long-time exposure to the hot corrosive environments portation of gases and liquids at cryogenic temperatures. occurring in gas turbines. Booklet provides laboratory 1130 MACHININGTHEAUSTENITICCHROMIUM-NICKEL and field test data, as well as the physical properties of this STAINLESS STEELS (16 pages, 1972) alloy. Discusses several grades of wrought nickel-containing, 515 SOME NICKEL-COPPER CASTING ALLOYS - austenitic stainless steels. Suggests the various ways to ENGINEERING PROPERTIES (12 pages, 1969) facilitate economic machining on a production basis, Presents chemical, physical and mechanical properties of recommendations for tooling materials, and overall ma- nickel-copper casting alloys 410, 411, 505 and 506. chining procedures for austenitic stainless steels. Discusses their high strength and toughness and excellent 1181 ALLOY DESIGN, USING SECOND PHASES resistance to corrosion by a variety of chemicals and (24 pages, 1973) marine environments . Includes information on heat treating, machining and joining. Reviews the use of second phases in alloy design. Subjects discussed include processes to insert second 517 NICKEL-CHROMIUM ALLOY 610 AND RELATED phases, design of second phase morphology, and the use CASTING ALLOYS - ENGINEERING PROPERTIES of second phases to control grain structure and disloca- (12 pages, 1969) tion networks. Covers optimization of alloy design for Discusses the nickel-base cast nickel-chromium-iron al- strength, ductility and toughness, fatigue resistance, loys 610, 611 and 705. Gives data on composition, stress-corrosion cracking resistance, and fabricability. mechanical properties, physical constants for these al- 1196 CAST HEAT-RESISTANT ALLOYS (8 pages, 1974) loys, which have excellent resistance to oxidation at elevated temperatures and are especially satisfactory for Presents chemical composition, mechanical and physical resisting corrosive attack of oxidizing acids and acid properties, specifications and design considerations for salts. Includes information on resistance to wear and the cast heat-resistant chromium-nickel-iron alloys. galling, heat treatment, machining and joining. Includes creep, stress-rupture and thermal fatigue properties. 534 MACHINING AND GRINDING SEVERAL CAST NICKEL-BASE HIGH-TEMPERATURE ALLOYS 1203 SIX REASONS FOR SPECIFYING NICKEL (16 pages, 1983) CARBURIZING STEELS (4 pages, 1974) Summarizes machining and grinding tests made on sev- Lists six important reasons for specifying nickel carbu- eral cast nickel-base high temperature alloys extensively rizing steels in industrial applications. Results of six used for gas turbine applications. Machining operations different testing procedures on various steels are shown investigated are those that occur most generally in pro- for (I) tension, (2) bending, (3) bending fatigue, (4) ducing finished parts, namely turning, end milling, drill- impact fatigue, (5) contact fatigue, and (6) impact plus ing, reaming, tapping and grinding. contact fatigue. 4

1205 THE ROLE OF NICKEL IN CARBURIZING STEELS 1240 THE INTERRELATION OF CORROSION AND (12 pages, 1974) FOULING OF METALS IN SEAWATER (16pages, 1982) An interpretation of research on the fundamental behav- Presents fouling characteristics of metals and alloys in iour of nickel in carburizing steels. Describes the effects seawater. Materials covered include carbon steel, an of nickel in terms of microstructure, mechanical proper- aluminum alloy, copper and copper-nickel alloys. The ties, and fracture toughness. test site is the LaQue Centre for Corrosion Technology, Wrightsville Beach, NC, U.S.A. 1208 WELDING 9% NICKEL STEEL - A REVIEW OF THE CURRENT PRACTICES (16pages, 1978) 1258 CORROSION FATIGUE PROPERTIES OF NICKEL- Reviews current worldwide practices for welding 9% CONTAINING MATERIALS IN SEAWATER nickel steel for cryogenics service. Welding processes (21 pages, 1977) covered include shielded metal-arc, metal inert gas, in- The corrosion-fatigue behaviour of a number of nickel- cluding shortcircuiting arc and pulsed spray arc, and containing materials in seawater has been evaluated at the submerged-arc welding. (Reprinted from Proceedingsof LaQue Centre for Corrosion Technology, Wrightsville the Welding Institute.) Beach, NC, U.S.A., using a technique involving smooth 1213 A DISCUSSION OF STAINLESS STEELS FOR (unnotched) cantilever beam specimens rotating at 1450 rpm for a maximum SURFACE CONDENSER AND FEEDWATER duration of 100 megacycles (about HEATER TUBING (32pages, 1975) 48 days). Evaluation has included nickel- and copper- base alloys, and some steels. Generally, test data suggest Discusses stainless steel condenser tubing materials for that a high ultimate tensile strength, high inherent pitting use in the power utility industry. Considerations for resistance, and a small grain size, are among the factors material selection include the condenser environment thatgive ahigh resistance to corrosion fatigue in seawater. and heat transfer characteristics. Includes data on Types Other main findings are that cathodic protection and 304 and 316. Also discusses use of stainless steel for flame-sprayed mild steel coatings improve the corrosion feedwater heater tubing. Includes specifications and pro- fatigue resistance of 18% Ni maraging steel, and that duction operations. (Reprinted from Amterican Iron and higher nickel content improves the corrosion fatigue Steel Institute.) resistance of cast bronze. 1220 SPECIFICATIONS AND FOREIGN EQUIVALENTS 1259 THE SUCCESSFUL USE OF AUSTENITIC FOR AUSTENITIC CHROMIUM-NICKEL STAINLESS STAINLESS STEELS IN SEAWATER (18pages, 1977) STEELS (8 pages, 1975) Austenitic stainless steels are providing excellent Lists specifications on 300 series stainless steels including troublefree service in seawater for pumps, propellers, AISI, ASTM, AMS, SAE, ACI, UNS and federal military valves, and other items of marine equipment. A failure specifications. Also tabulates nearest foreign equivalents occurs occasionally as the result of deep localized pitting including British, French, German, Italian, Swedish, in a crevice. Data are given showing that austenitic, Russian, and Japanese. ferritic and martensitic stainless steel suffer pitting in 1229 STANDARD WROUGHT AUSTENITIC STAINLESS crevices and under deposits in quiescent seawater. Auste- STEELS (12pages, 1975) nitic stainless steels remain free from attack in high velocity seawater. Low purity ferritic and the martensitic Covers wrought austenitic stainless steels standardized stainless steels frequently pit in high velocity seawater. by the American Iron and Steel Institute. Materials include Crevice corrosion can be effectively controlled with the chromium-nickel Type 300 series and the chromium- cathodic protection from iron, zinc, aluminum or magne- nickel manganese Type 200 series. Presents composition, sium galvanic anodes or impressed current cathodic distinguishing characteristics, engineering properties, and protection by polarization to -0.6 volts versus Calomel. processing and fabrication details. (Reprinted from Austenitic stainless steel, in many situations, performs Materials Engineering.) well because it is a component of a multialloy assembly 1232 FRACTURE TOUGHNESS AND RELATED utilizing iron or steel. Gives examples from field experi- CHARACTERISTICS OF THE CRYOGENIC NICKEL ence. STEELS (48pages, 1983) 1262 RESISTANCE OF STAINLESS STEEL TO Discusses comprehensive compilation ofthe fracture tough- CORROSION IN NATURALLY OCCURRING ness behaviour and metallurgical characteristics of the 21/4, WATERS (20pages, 1980) 31/2, 5 and 9% nickel steels for cryogenic application. Reviews behaviour of conventional stainless steels in Mechanical property data include tensile, notch toughness, freshwater, chloride-containing waters and seawater. In- fracture toughness and fatigue properties at ambient and cluded are the austenitic Types 304 and 316 stainless cryogenic temperatures. Includes effect of cold work, heat steels, Type 410 and the ferritic 8Cr/2Mo/Ti stainless treatment and welding on mechanical properties. steels. Factors of importance to consider to minimize (Welding Research Council Ltd. Bulletin N 204.) localized corrosion in chloride-containing waters are: 1238 LOW-TEMPERATURE PROPERTIES OF NICKEL avoidance of crevices, cathodic protection, high velocity, intermittent exposure and low oxygen level. Also consid- ALLOY STEELS (36 pages, 1975) ers welded joints, soft soldered joints and brazed joints Presents mechanical and physical property data and met- (Reprinted from Transactionsof the 2nd Spanish Corro- allurgical characteristics of nickel-containing steels at siOn Congress.) temperatures down to -320'F. Materials covered include 21/4, 3/2, 5, 8 and 9% nickel steels as well as other nickel alloy steels, both wrought and cast. Reviews standard specifications and code qualifications for use of these materials at subzero temperatures. 5 1265 CA-706 COPPER-NICKEL ALLOY HULLS: THE 1285 CORROSION RESISTANCE OF NICKEL- COPPER MARINER'S EXPERIENCE AND CONTAINING ALLOYS IN ORGANIC ACIDS AND ECONOMICS (28pages, 1977) RELATED COMPOUNDS (68 pages, 1979) Actual four-year operating experience with the CA-706 Reports on corrosion data for numerous alloys in many copper-nickel alloy hull of a shrimp trawler has shown organic acids and other organic media over a wide range it to be a good business investment. Copper-nickel alloy of exposure conditions. Materials covered include the was selected because of its corrosion resistance and stainless steels, iron-base alloys of high alloy content, biofouling resistance when operating in seawater. De- nickel-base alloys and some copper-base and cobalt-base tails of the design and construction of the Copper Mari- alloys. Includes cast and wrought alloys. The corrosive ner are given along with an economic analysis showing media include acetic acid, formic acid, acrylic acid, fatty fuel savings, maintenance savings and increased avail- acids, di- and tricarboxylic acids, napthenic acids and ability for fishing derived from using this material. various esters. (Reprint of SNAME publication.) 1300 THE CORROSION RESISTANCE OF NICKEL- 1267 ABRASION-RESISTANT CASTINGS FOR CONTAINING ALLOYS IN FLUE GAS HANDLING COAL - PROPERTIES AND USES OF DESULFURIZATION AND OTHER SCRUBBING THE Ni-HARD IRONS (24 pages, 1978) PROCESSES (80pages, 1980) Presents engineering properties and applications of Ni-Hard A comprehensive treatment of the performance of nickel Type I and Type 4 castings .Includes mechanical properties, alloys used in flue gas desulfurization scrubbing systems casting design and fabrication in formation. Illustrates appli- is assembled in this bulletin. Corrosion data are reported cations of these abrasion- and wear-resistant castings in the from Inco's corrosion test spool data bank and plant coal industry and in coal-fired power plants. corrosion tests under actual process conditions. Alloy 1278 IN-787-A PRECIPITATION HARDENING ALLOY performance is given for flue gas scrubbing systems STEEL, PROPERTIES AND APPLICATIONS which have gained commercial status as well as other wet (16 pages, 1978) scrubbing systems. Methods are discussed for the use of scrubbing systems to meet the stringent S02 emission IN-787 is a low-carbon precipitation hardenable alloy regulations set by the United States Environmental Pro- steel that combines high-strength, low-temperature tough- tection Agency (EPA). ness and excellent notch ductility with good fabricability. This combination allows IN-787 to be used in a wide 1304 THE INFLUENCE OF CORROSION AND FOULING range of engineering applications including trucks, off- ON STEAM CONDENSER PERFORMANCE highway vehicles, valves, fittings and pressure vessels, (20 pages, 1979) offshore rigs, construction and lifting equipment, motor Discusses performance of some alloys used as condenser shafting, heavy duty wheels and rims, rail car structural tubes in steam power plants. Materials investigated in- assemblies, rudders, and selected ship hull plates. It is clude copper alloys, ferritic and austenitic stainless steels especially suitable for service in the Arctic or other areas and titanium. Condenser tube performance in saltwater where low temperature toughness is important. and in brackish, fresh- and recirculated cooling-waters 1279 STRESS CORROSION CRACKING BEHAVIOUR are given. Covers biofouling resistance of copper-nickel OF WROUGHT Fe-Cr-Ni ALLOYS IN A MARINE alloys in seawater for improving condenser tube perform- ATMOSPHERE (12pages, 1978) ance. (Reprinted from Journal of Materialsfor Energy Systems.) Reports results of five-year testing on the stress-corrosion cracking behaviour of iron-chromium-nickel alloys 1305 THE RESISTANCE OF COPPER-NICKEL ALLOYS exposed in a marine atmosphere at Kure Beach, NC, TO AMMONIA CORROSION IN SIMULATED STEAM U.S.A. Materials tested included stainless steels, nickel CONDENSER ENVIRONMENTS (8 pages, 1980) base alloys and several Fe-Cr-Ni alloys in different Discusses resistance of condenser tube copper alloys to metallurgical conditions. Evaluation program was con- ammonia corrosion. Gives laboratory test results on com- ducted on U-bend, three-point-loaded bent beam and mercially produced condenser tubes of a number of cantilever beam specimens at various levels of applied alloys exposed to several simulated steam condenser stress. (Reprinted from Materials Performance.) environments. The copper-nickel alloys are shown to be 1280 GUIDE TO THE WELDING OF COPPER-NICKEL extremely resistant to general ammonia attack. (Reprinted ALLOYS (80 pages, 1979) (4441) from Proceedings of the American Power Conference.) Discusses various welding processes and filler metals 1318 THE CORROSION RESISTANCE OF NICKEL- commonly used for joining copper-nickel alloys. Pri- CONTAINING ALLOYS IN SULPHURIC ACID AND mary alloys considered are the 9Cu-lONi and 7Cu- RELATED COMPOUNDS (96pages, 1983) 3ONi types, but other copper-nickel alloys are included. Presents numerous laboratory and plant corrosion tests Covers choice of welding process, weld preparation, on the performance of nickel and nickel alloys in contact welding technique and inspection and testing of joints, with sulphuric acid, sulphur dioxide, sulphur trioxide and and welding procedure and welder qualification tests. oleum. Service experience contributed extensively to the Includes applications of copper-nickel alloys in data. Discusses industrial applications such as sulphuric desalination of seawater, heat exchangers and for boat acid manufacture, phosphoric acid manufacture, hulls. hydrometallurgy, ammonium sulphate manufacture, aluminum sulphate manufacture, organic materials, pickling and chlorine drying. 6

2828 CORROSION RESISTANCE OF THE AUSTENITIC 4368 MATERIALS FOR CRYOGENIC SERVICE - CHROMIUM-NICKEL STAINLESS STEELS IN ENGINEERING PROPERTIES OF AUSTENITIC CHEMICAL ENVIRONMENTS (20pages,-1976) STAINLESS STEELS (50 pages, 1974) Discusses corrosion resistance of AISI standard auste- Presents data on the composition, mechanical and physi- nitic stainless steels to waters, salt solutions, inorganic cal properties of austenitic stainless steels normally used acids, bases, organic compounds, foods, and elementary for cryogenic applications. Summarizes specifications substances, with tables of corrosion rates. Includes a brief and pressure vessel design code information from the discussion of the types of corrosion of stainless steels. United States, the United Kingdom, West Germany, Italy and Sweden. Contains 33 tables and 35 figures. 2978 AUSTENITIC CHROMIUM-NICKEL STAINLESS Data include tensile properties, compressive properties, STEELS AT AMBIENT TEMPERATURES - MECHANICAL AND PHYSICAL PROPERTIES impact test data, effect of sensitization, fracture toughness, fatigue strength, welding, properties of welded (44 pages,-1962) joints, and physical properties. Includes tables and graphs showing the properties of AISI and ACI standard austenitic stainless steels at nor- 4383 IN-519 CAST CHROMIUM-NICKEL-NIOBIUM HEAT- mal temperatures. Data are presented on tensile, RESISTING STEEL - ENGINEERING PROPERTIES compressive, fatigue, shear, and impact properties of the (12 pages, 1976) wrought steels in the annealed and cold-worked condi- IN-519 was developed primarily for the production of tions, and of cast steels. Includes data on density, thermal, centrifugally cast tubes and is an optimized composition electrical, elastic, and magnetic properties. of HK-40 steel. Describes the composition and physical 2980 AUSTENITIC CHROMIUM-NICKEL STAINLESS metallurgy of the material and presents data on mechanical properties, weldability, thermal fatigue, corrosion, STEELS AT ELEVATED TEMPERATURES - MECHANICAL AND PHYSICAL PROPERTIES and physical properties. (24 fiages, 1968) 4393 CAST NICKEL ALLOY STEELS - ENGINEERING Includes tables and graphs showing the properties of PROPERTIES (24 pages, 1975) AISI and ACI standard austenitic stainless steels at el- Provides mechanical property data for four well-estab- evated temperatures. Data are presented on short time lished cast-nickel alloy steels within various ranges of tensile, creep, and stress-to-rupture properties and allow- tensile strength. Includes information on the effects of able design stresses. Includes data on density, electrical, section size and heat treatment. thermal, elastic, and magnetic properties. 4419 18% NICKEL MARAGING STEEL -ENGINEERING 4077 NICKEL SG IRON - ENGINEERING PROPERTIES PROPERTIES (30 pages, 1981) (12 pages, 1974) Reviews 18% maraging steels and their properties. Con- Discusses the types of spheroidal graphite cast irons and tains chapters on commercial and national specifica- their mechanical and physical properties. Includes sections, melting practice, mechanical and physical tions on design considerations, heat treatment, and fabri- properties, processing and forming, welding, machin- cation. ing, descaling and pickling, and corrosion characteris- 4319 COPPER-NICKEL AND OTHER ALLOYS FOR tics. DESALINATION PLANTS (64 pages, 1981) 4421 THE WELDING OF FLAKE AND SPHEROIDAL A compendium of papers on materials for desalination GRAPHITE Ni-RESIST CASTINGS (6 pages, 1976) plants. Includes extensive corrosion data, information on Although flake-graphite grades of Ni-Resist cast iron are fabrication techniques, mechanical properties and cast- capable of being welded satisfactorily, provided that ing considerations. sulphur and phosphorous content are controlled, satisfactory welds on spheroidal graphite Ni-Resist are more 4353 COPPER-NICKEL ALLOYS -ENGINEERING PROPERTIES AND APPLICATIONS (12pages, 1981) difficult to achieve. Covers necessary compositional and welding parameter controls. Introduction to copper-nickel alloys, including standards and specifications, mechanical properties, physical properties, corrosion and antifouling properties, and fabrication techniques. Describes uses in marine, chemical, process, automotive, and aquacultutre. 7 Section 11 Publications by AISI Publications in this section, with catalogue numbers starting at 9001, were originally published by the Committee of Stainless Steel Producers, American Iron and Steel Institute. The information was based on extensive research, data and various alloys and grades available at the time of publication.

9001 CLEANING AND DESCALING STAINLESS STEEL Defines galling and the various types of wear, and typical (36 pages, 1982) wear and galling test methods are described and illus- Because stainless steels have optimum resistance to cor- trated. Suggests how to avoid problems through selection rosion when clean and free of scale and weld discolora- of alloys, the application of wear coatings and the use of tion, proper and efficient cleaning and descaling are vital lubricants. Fifteen tables provide chemical composition steps on making anything of stainless steel. Describes and mechanical property data on 57 AISI-numbered several pickling and cleaning methods. Acids and typical stainless steels and 11 proprietary alloys. cleaning systems are identified, variations in time, tem- 9008 STAINLESS STEELS FOR PUMPS, VALVES, AND perature, and techniques are discussed. FITTINGS (24 pages, 1978) 9002 WELDING OF STAINLESS STEELS AND OTHER Gives an overview of the role of stainless steels in JOINING METHODS (46pages, 1979) equipment used for moving and controlling fluids. Seven Presents information to help design engineers better tables present data on all AISI-numbered stainless steels, understand the welding characteristics of stainless steels. and 38 photographs, including cut-away views, show Contains 31 tables and 40 figures on the metallurgical construction details and how different stainless steel characteristics of stainless steels and the changes that can types are used to meet fabrication and end-use require- take place during welding, different welding and joining ments. methods, joint designs, weld filler-metal selection, ele- 9009 STAINLESS STEELS FOR PULP AND PAPER ments that affect welding, and the welding processes MANUFACTURING (56pages, 1982) normally used with stainless steels. Also discusses pipe welding, weld overlays, welding clad plate, welding Reviews the use of stainless steels in pulp mills, from dissimilar metals, and post-weld cleaning and finishing. wood lot to fourdrinier. Covers sulphate and sulphite pulp processes and describes typical environments. Discusses 9003 STAINLESS STEEL FASTENERS-A SYSTEMATIC reasons for using stainless steels in digesters, brown stock APPROACH TO THEIR SELECTION (28 pages, 1976) washers, bleach plants, and chemical recovery. Covers Shows how to select stainless steel fasteners for typical paper mills, stock preparation, paper machines, saveall applications. Tables, charts, and 45 photographs show systems, and the materials requirements for pulp and fasteners and provide data on the chemical compositions paper mill odor-control equipment. Contains 28 draw- of the nine typical fastener stainless steels. Also gives ings, diagrams, and photographs. fastener mechanical requirements, strength-to-weight 9010 STAINLESS STEELS FOR BUILDING EXTERIORS ratios of various fastener materials, high and low-tem- (36 pages, 1984) perature properties, allowable shear stresses, suggestions for proper torque, and guidelines for selection based on Displays 15 outstanding examples of building with stain- galvanic action in a fastened joint. less steel exteriors. Full-color photographs dramatize the architectural beauty of stainless steels, and there are 9004 HIGH-TEMPERATURE CHARACTERISTICS OF drawings for each building to show important construc- STAINLESS STEEL (48 pages, 1979) tion details of the exterior. Building categories include Discusses the factors to be considered in designing equip- hospital, science centre, museum, rail maintenance facil- ment and selecting construction materials for high-tem- ity, space needle, sports complex, diplomatic chancery, perature service. The 56 tables and 52 charts help design bank, and union hall. engineers better understand stainless steels in terms of typical engineering properties and corrosion-resistance 9011 STAINLESSSTEELS FOR MACHINING (76pages, 1985) characteristics at elevated temperatures. Provides a comprehensive discussion of stainless steels for machining applications. With 28 tables, 43 charts and 9005 ROLE OF STAINLESS STEELS IN INDUSTRIAL illustrations, contains basic information on all stainless HEAT EXCHANGERS (48pages, 1976) steels, giving special attention to the free-machining Reviews the various considerations for using stainless grades. Describes good shop practices and offers design steel in heat exchange service. Discusses corrosion resist- suggestions for getting optimum productivity in machin- ance and mechanical properties of the 15 stainless steels ing components from stainless steels. most commonly used for heat exchange service, including high-and low-temperature properties, heat-transfer 9012 FINISHES FOR STAINLESS STEELS (60pages, 1983) characteristics, cleanliness factors, design guidelines, Describes standard industry finishes and several propri- and suggestions for installation and maintenance. etary finishes for stainless. Twenty-nine photographs and 9006 REVIEW OF THE WEAR AND GALLING six tables help designers and specifiers better understand CHARACTERISTICS OF STAINLESS STEELS rolled, ground, and buffed finishes readily used on stain- (32 pages, 1978) less steel sheet, strip, plate, bar, wire, tubing and pipe. Shows the distinction between repairable and Discusses design factors in assemblies where sliding nonrepairable finishes. Describes techniques for blend- contact exists between wrought stainless steel and an- ing welds, scratches, and other surface-damaged areas to other metallic component, not necessarily stainless steel. match original finishes. Discusses considerations for 8

specifying prefinished stainless steels, and suggestions 9019 COLD FORMING STAINLESS STEEL BAR AND are made for finishing by product manufacturers and WIRE (24 pages, 1976) fabricators. Describes many processes used for cold forming stain- 9013 STAINLESS STEELS IN AMMONIA PRODUCTION less steel bar and wire including heading, piercing, extru- (24 pages, 1978) sion, trimming, thread rolling, swaging, and simple Discusses selection of stainless steels from process equip- bending. Gives special attention to the stainless steel used ment in ammonia production plants. Contains 22 dia- specifically for cold-forming operations, and a table grams, charts, and tables illustrating a typical ammonia shows trade names for the widely used cold-forming production process, and provides technical data on 18 types. More than 50 photographs and illustrations drama- stainless steels that might be used for construction mate- tize the versatility of stainless steels. rials. Also covers materials for desulphurization, cata- 9021 ROLE OF STAINLESS STEEL IN PETROLEUM lytic steam reforming, carbon monoxide shift, carbon dioxide removal, methanation, synthesis, and turbine- REFINING (60 pages, 1977) driven centrifugal compression trains. Provides data on Helps materials engineers identify the engineering mate- the candidate stainless steels. rials used in all phases of petroleum refining. Diagrams and descriptions show applications for stainless steels in 9014 DESIGN GUIDELINES FOR THE SELECTION AND distillation, catalytic cracking, coking, hydrotreating, USE OF STAINLESS STEELS (52 pages,-1976) reforming, and hydrocracking; in gas, hydrogen, and Helps designers better understand the large family of amine plants; in sulphur acid alkylation; and in sour water corrosion-resistant stainless steels. Describes typical cor- strippers. Describes and illustrates types and nature of rosion modes, and how to select materials to minimize or corrosion problems frequently encountered in petroleum prevent corrosion. Forty-seven figures help illustrate refining. important characteristics of and end-use applications for 57 different stainless steel types, including chemical 9022 AUTOMOTIVE STAINLESS STEELS (68 pages, 1985) compositions, physical and mechanical properties, prop- Stainless steels are one segment of the steel spectrum, but erties at elevated temperatures, and heat-transfer charac- they serve a multitude of automotive design require- teristics. ments. Documents where stainless steels are used in today's automobiles, to stimulate thinking for tomor- 9015 STAINLESS STEEL SOLAR COLLECTOR PANELS row's applications. Text is divided into five major com- (28 pages, 1981) ponent sections -exhaust, trim/decorative, engine, chassis, An overview on the application of stainless steels to solar and fasteners (plus miscellaneous), and each section collectors, for water and comfort heating. Discusses the identifies all stainless steel types used therein. results of a two-year test program, conducted by the AISI Committee of Stainless Steel Producers, in which candi- 9024 DESIGN GUIDELINES FOR STAINLESS STEEL IN PIPING SYSTEMS (27pages,-1980) date materials were exposed in a service environment to typical potable and swimming-pool waters. Also de- Provides information on the design, fabrication, installa- scribes collector panel design and fabrication, plus duration, and economy of stainless steel in piping systems to ble but inexpensive solar-selective coatings. Seven figures help piping specialists and design engineers save money, help illustrate material characteristics and panel manu- time, and effort in the several diverse industries using facturing, and numerous photographs show commercial piping systems. Discusses advantages and limitations, and residential applications. costs in terms of design, material, fabrication, and erection, and applicable standards. Fourteen tables provide 9016 STAINLESS STEEL FORGINGS (32 pages, 1975) data on physical and mechanical properties. Gives design guidelines on stainless steel forgings. Cov- 9025 STAINLESS STEEL FOR BULK MATERIALS ers forging terminology, properties, tolerances, nondestructive inspection, and materials available that HANDLING (22pages, 1980) are capable of meeting special forging requirements or Illustrates some of the equipment frequently constructed quality tests. Describes 27 parts forged of stainless steel; of stainless steel, and discusses factors to be considered illustrations show a wide variety of cost-saving applica- in specifying materials of construction. Describes those tions, ranging in size from a few ounces to a nuclear characteristics of stainless steels appropriate for bulk reactor core support weighing 50 000 kg forged from handling, such as strength, resistance to abrasion or 133 000 kg stainless steel ingot. erosion, and cleanability. Provides information on fabrication, surface protection, and cleaning. Gives physical 9018 STAINLESS STEELS FOR MASS and mechanical properties for the four general-purpose TRANSPORTATION (24 pages, 1977) stainless steels. Since 1930 stainless steel has been used for some of the 9026 STAINLESS STEELS FOR EVAPORATORS/ best-known transportation systems in the world, and it is CONCENTRATORS (22 pages, 1981) still the material preferred for modem light-weight, high- Concentration of liquids, or the removal of moisture from speed mass transit equipment. Reviews why stainless products by evaporation, are process operations used in steels are preferred for mass transit, in both vehicle and many industries - food, beverage, chemical, pulp and architectural applications. Describes mass transit in Phila- paper, pharmaceutical, water and waste-water treatment. delphia, New York, Chicago, Cleveland, and Montreal, As process engineers strive to increase production, gen- and shows where all-stainless steel cars are lighter in erally through increased temperature and pressure or by weight than comparable aluminum cars. the use of more efficient evaporator trains, materials of construction in these units become more important. De- scribes how and where stainless steels are being used to assure long, trouble-free service in the evaporator/con- centrator environments. 9

9029 ROLE OF STAINLESS STEELS IN DESALINATION 9032 STAINLESS STEEL: EFFECTIVE CORROSION (33 pages, 1974) CONTROL IN WATER AND WASTE-WATER A state-of-the-art report on the use of stainless steel in TREATMENT PLANTS (25 pages, 1974) distillation-type desalination plants. Includes informa- Illustrates 46 typical applications for stainless steels in tion on the selection and fabrication of stainless steel water and waste-water treatment plants, including con- equipment. Part of the study is a report on the three-year trol panel, strainers, aerators, tanks, weirs, clarifiers, operation of a 11 000 - litre per-day distillation plant in tubing and pipes, fasteners, filters, centrifuges, railings, Freeport, Tx, U.S.A., which served as an in-service test and architectural products. Describes the properties of for stainless steels. Photographs show typical details of stainless steels, the forms in which they are available, the test plant and specific corrosion problems that were their fabrication considerations, and their finishes. encountered in its operation. 9034 STAINLESS STEEL MEMBRANE ROOF 9030 A DISCUSSION OF STAINLESS STEELS FOR (23 pages, 1980) SURFACE CONDENSERS AND FEEDWATER Describes the design, fabrication and erection of the first HEATER TUBING (32 pages, 1974) all-stainless steel, air-supported single membrane roof at Describes the reasons behind the rapid growth of stain- Dalhousie University, Halifax, N.S., Canada. The theory less steels for condenser and feedwater tubing. Discusses of a metallic membrane is explained, and the solution of the environments involved - steam-side conditions, wa- the problem of double curvature (what happens to a single ter-side conditions, and cooling water types - and how membrane when it loses its air support) is described. Also they influence materials choices. Provides data on physi- describes and illustrates unique methods used to fabricate cal and mechanical properties of the most frequently used and transport large pie-shaped segments of the roof to the stainless steel types, and frequently encountered corro- job site. sion modes are described. 9031 STAINLESS STEEL - SUGGESTED PRACTICES FOR ROOFING, FLASHING, COPINGS, FASCIAS, GRAVEL STOPS, DRAINAGE (32 pages, 1972) Contains tables and detail drawings describing the proper application of stainless steel to moisture protection in building construction. Dozens of drawings include typical designs for batten seam, standing seam, and flat seam roofing, industrial roofing panels, copings, fascias and gravel stops, counter or cap flashing, through-wall flashing, spandrel flashing, expansion joints, and roof drainage. A table on design factors, keyed to SMACNA Manual plate numbers, suggests the stainless steel type to use, its thickness, and detail considerations. 10 Section III Publications by NiDI Literature carrying catalogue numbers 10 001 and up are published by the Nickel Development Institute.

10 001 SOLVING HIGH-TEMPERATURE PROBLEMS IN A wide-ranging, well-illustrated dissertation on nickel- OIL REFINERIES AND PETROCHEMICAL bearing and nickel-base alloys that have proved useful PLANTS (6 pages) in many ways in the process industries where they are By C.M. Schillmoller, reprinted from Chemical often used to avoid foreseeable problems, and for Engineering, Jan 6, 1986. resolving difficulties not anticipated but arising in Because the cost of chemical process industries plant practice. shutdowns has become so high, considerations of 10 006 HIGH-PERFORMANCE AUSTENITIC STAINLESS initial cost in alloy selection for high-temperature STEELS IN THE PULP AND PAPER INDUSTRY components are being overshadowed by life-cycle (6 pages) cost. Heat-resistant alloys must be selected that will not only meet the requirements of a particular applica- ByA. Garner, presented at symposium, theMetallurgical tion but also provide long-term performance. Society of the Canadian Institute of Mining and Metallurgy (CIM) and NiDI, Toronto, Aug 17-20, 10 002 EVALUATING INSTALLED COST OF 1986; reprinted from CIM Proceedings, Nickel CORROSION-RESISTANT PIPING Metallurgy, Series NO25-7/6/1/3, Vol. 1, (2), 1986. (12 pages plus 24-page Appendix) The corrosion resistance of recently developed stainless By Arthur H. Tuthill, containing most of material (in steels is reviewed with reference to their performance in different form) contained in six articles published by pulp mill bleach plants. Field and laboratory test data are author in Chemical Engineering during 1986. used to compare the merits of different alloys, and the For engineers and specifiers who select materials for background to alloy formulation is outlined. How to corrosion-resistant piping, analyzed are pipe systems, avoid preferential corrosion of welds is also covered. sizes and materials-metallic, nonmetallic, compos- 10 007 NICKEL'S CONTRIBUTION IN AIR POLLUTION ite and lined. Summarizes comparative costs, itemizes ABATEMENT (8 pages) nine-step approach to selection of piping materials, supports conclusions with complete cost calculations By C.M. Schillmoller, presented at symposium, the (in digital and graphic form), and highlights and seeks Metallurgical Society of the Canadian Institute of to correct inconsistencies that have limited usefulness Mining and Metallurgy (CIM) and NiDI, Toronto, of earlier studies on topic. Aug 17-20, 1986; reprinted from CIM Proceedings, Nickel Metallurgy, Series NO 25-7/6/1/3, Vol. 1, (2), 10 003 REVERSE OSMOSIS - WHICH STAINLESS 1986. STEEL TO USE? (4 pages) A better understanding of process chemistry and per- By J. W. Oldfield and Brian Todd, reprinted from formance limitations of certain construction materials Middle East Water and Sewage, Oct 1986. has translated into more effective equipment design Stainless steels are well suited to the requirements of and improved emission control operations. Discussed reverse osmosis as their resistance to aqueous corrosion are high-nickel alloys and specialty stainless steels is high, thus avoiding potential membrane-scaling ions used widely in incinerators and wet scrubbers. contaminating the process. Describes the behaviour of 10 008 H20: NICKEL'S CONTRIBUTION TO DISTILLED stainless steels in aqueous environments and assists in WATER, DAMS AND CONDENSERS (9 PAGES) selection of suitable alloys for particular conditions. By Arthur H. Tuthill, presented at symposium, the 10 004 FABRICATION AND POST-FABRICATION Metallurgical Society of the Canadian Institute of CLEANUP OF STAINLESS STEELS (4 pages) Mining and Metallurgy (CIM) and NiDI, Toronto, By Arthur H. Tuthill, reprinted from Chemical Aug 17-20, 1986; reprinted from CIM Proceedings, Engineering, Sep 29, 1986. Nickel Metallurgy, Series NO 25-7/6/1/3, Vol. 1, (2), 1986. The surface condition of stainless steels is critical where the product must not be contaminated; pharma- Nickel alloys are used extensively in the production, ceutical, food and nuclear plants and where the stain- handling and treatment of high purity, natural and less must resist an aggressive environment. Embedded waste waters. The corrosion resistance of these alloys iron, grease and heat tint can initiate corrosion unless in various waters is examined. Examples from nick- properly removed or, in some cases, prevented. Pro- el's contribution in applications ranging from hospi- vides a guide to solving the problem. tals through large-scale dams, municipal treatment plants and power plants are provided. 10 005 NICKEL IN THE PROCESS INDUSTRIES-AN ANXIETY CLOSET OF MATERIALS SELECTION 10 009 BURGERS, FRIES, COKE AND STAINLESS MONSTERS (5pages) STEEL (6 pages) By C.P. Dillon, presented at symposium, the By J.S. Pettibone, presented at symposium, the Metallurgical Society of the Canadian Institute of Mining Metallurgical Society of the Canadian Institute ofMining and Metallurgy (CIM) and NiDI, Toronto, Aug 17-20, and Metallurgy (CIM) and NiDI, Toronto, Aug 17-20, 1986; reprinted from CIM Proceedings, Nickel 1986; reprinted from CIM Proceedings, Nickel Metallurgy, Series N° 25-7/6/lf3, Vol. 1, (2), 1986. Metallurgy, Series N 25-7/6/l/3, Vol. 1, (2), 1986. 11

Discusses the choice of nickel-containing stainless steel 10 014 WELDING STATUS OF DUPLEX STAINLESS for many applications in the food service equipment STEELS FOR OFFSHORE APPLICATIONS (8 pages) market, based on several of the material's inherent prop- By N. Stephenson, reprinted from Welding & Metal erties. Summarizes six of the most important reasons for FabricationJournal, Vol. 55, (4 & 5), 1987. its use-corrosion resistance, durability, cleanability, economy, eye appeal and food flavour protection. Deals with welding metallurgy of duplex stainless steels and their application in pipelines and flowlines, 10 010 ARCHITECTURE-A DEMANDING MARKET FOR as well as discussing the topside plant of platforms, STAINLESS STEEL (7pages) quality assurance, and quality control. By B.A. Smits, presented at symposium, the 10 015 ALLOY SELECTION IN WET-PROCESS Metallurgical Society of the Canadian Institute of PHOSPHORIC ACID PLANTS (10 pages) Mining and Metallurgy (CIM) and NiDI, Toronto, Aug 17-20, 1986; reprinted from CIM Proceedings, By C.M. Schillmoller, reprinted from Process Nickel Metallurgy, Series NO25-7/6/l/3, Vol. 1, (2), Industries Corrosion, The Theory and Practice, 1986. published by National Association of Corrosion Engineers, 1986. Describes why stainless steels perform well in architectural applications. While strength and corrosion Although the equipment and methods involved in resistance are important to function and durability, making and utilizing phosphoric and sulphuric acid appearance is crucial. Major mill problems solved are are continually undergoing refinement and improve- those of physical tolerances, surface finish, and deliv- ment, not sufficient advantage seems to have been ery of dead-flat material with superior uniformity of taken of new alloys that contribute substantially to color, coil to coil. reduction in capital investment, provide higher efficiency and increase operating capabilities. 10 011 NICKEL-CONTAINING MATERIALS IN MARINE This paper opens a window on a group of cost- AND RELATED ENVIRONMENTS (8 pages) effective alloys and discusses potential and actual By Brian Todd, presented at symposium, the applications. Metallurgical Society of the Canadian Institute of 10 016 TEST TECHNIQUES FOR PITTING AND CREVICE Mining and Metallurgy (CIM) and NiDI, Toronto, Aug CORROSION RESISTANCE OF STAINLESS 17-20,1986; reprinted from CIM Proceedings,Nickel STEELS AND NICKEL-BASE ALLOYS IN Metallurgy, Series N"25-7/6/1/3, Vol. 1, (2), 1986. CHLORIDE-CONTAINING ENVIRONMENTS The need for large volumes of water for cooling (18 pages) purposes in the desalination industry has resulted in By Dr. John W. Oldfield, reprinted from International the location of many major industries on the coast. MaterialsReviews, Vol. 32 (3), 1987. Recognized as the most corrosive natural environment, marine areas cause design problems in the Test methods currently available for determining the selection of materials that will give good performance resistance of stainless steels and related alloys to at reasonable cost. pitting and crevice corrosion in chloride environments are assessed. Nickel-containing materials - such as copper- nickel alloys, stainless steels and nickel-base alloys The present understanding of the mechanisms of have been found to provide optimum techno-eco- pitting and crevice corrosion are examined, and the nomic solutions in many cases. Reviewed are their major factors affecting the process are noted. corrosion resistance, fabricability and cost. Accelerated and exposure test techniques are considered in relation to their ability to provide an accurate ranking 10 012 NICKEL-BASE ALLOYS IN THE POWER of materials, and to relate the service conditions. INDUSTRY (6 pages) 10 017 STAINLESS STEEL IS COST-EQUIVALENT TO ByJ. Brown and B .Montford, presented at symposium, FRP FOR USE IN THE BLEACH PLANT (4 pages) the Metallurgical Society of the Canadian Institute of Mining and Metallurgy (CIM) and NiDI, Toronto, Aug By Arthur H. Tuthill, reprinted from Pulp and Paper, 17-20,1986; reprinted from CIM Proceedings,Nickel Jun 1987. Metallurgy, Series N' 25-7/6/1/3, Vol. 1, (2),1986. Estimated costs of bleach plant piping play a major Nickel-base alloys are used extensively in the power role in material selection, especially in mills where industry-in heat exchanger tubing in nuclear plants for UNS S31703 stainless steel piping (nominal nickel heat rejection from moderator and reactor systems, and content, 11-15 per cent) is suffering corrosion and the production of steam. Failures are described and requires upgrading. comparisons of the behaviour of different alloy types Installed costs are developed for reinforced thermo- are given. Two research programs are also outlined. setting resin piping, for stainless steel, and for nickel- base alloy piping. 10 013 OPPORTUNITIES FOR NICKEL IN THE OIL AND Factors having a major influence on installed cost GAS MARKET (18 pages) estimates are identified so that realistic cost compari- Four papers by C.M. Schillmoller and Brian Todd, sons can be established. presented at symposium, the Metallurgical Society of 10 018 INFLUENCE OF CARBIDE CONTENT ON THE the Canadian Institute of Mining and Metallurgy STRESS CORROSION CRACKING OF Ni-RESIST (CIM) and NiDI, Toronto, Aug 17-20,1986; reprinted CAST IRONS IN WARM SEAWATER (9 pages) from CIM Proceedings,Nickel Metallurgy, Series N' 25-7/6/1/3, Vol. 1 (1), 1986. By J.V. Dawson and B. Todd, reprinted from BCIRA Journal, Nov 1987. These papers cover applications of nickel-containing alloys in deep sour gas productions, enhanced oil Wide variations in carbide content can occur at compo- recovery and offshore. sitions within the type D2 Ni-Resist specification (UNS 12

F43000; nominal nickel content, l 8-22percent) and the been determined over periods up to a dozen years. form of stress corrosion is influenced by it. Exposure tests were carried out, in full immersion To minimize the risk of stress corrosion cracking, it and tidal conditions, on specially designed concrete is recommended that the iron should be well inocu- blocks. Mild steel specimens were also tested for lated, should have relatively high silicon and low comparison. chromium contents, and castings should be stress Corrosion of exposed stainless steel was localized, relieved particularly after weld repairs to keep total not extensive, and affected neither the strength nor stress levels to a minimum. ductility of the specimens. Contrary to expectation, crevice corrosion occurred 10 019 ALLOY SELECTION FOR CAUSTIC SODA on only one of the 42 test specimens, and only after SERVICE (9 pages) 12.5 years total immersion. By C.M. Schillmoller, 1988. It is considered that the alkalinity of the concrete A number of construction materials may be used to was responsible for minimizing corrosion on both produce and handle caustic solutions. Selection factors embedded and external areas of stainless steel. include practicality, availability, mechanical properties, corrosion resistance, risk/benefit 10 023 LIFE-CYCLE COST COMPARISON OF considerations and economics. ALTERNATIVE ALLOYS FOR FGD COMPONENTS Critical factors in caustic service are listed, as are By J.D. Redmond, R.M. Davison and Y.M. Shah, the metals and alloys most frequently considered for presented at Air Pollution Seminar, Buffalo, NY, use in caustic soda - carbon steel, stainless steels, U.S.A., Oct 1987. nickel and high-nickel alloys. Life-cycle cost analyses of the use of stainless steels and other corrosion-resistant alloys were compared 10 020 ALLOYS TO RESIST CHLORINE, HYDROGEN with those of neoprene-lined carbon steel in the con- CHLORIDE AND HYDROCHLORIC ACID struction of FGD components. (5 pages) Although capital costs of the FGD components By C.M. Schillmoller, 1988. constructed of stainless steel and corrosion-resistant Gaseous chlorine at low temperatures and in the ab- alloys are generally higher than those of the lined sence of moisture is not severely corrosive and is carbon steel components, the life-cycle costs are less commonly handled by carbon steel. Dry hydrogen in most cases, often substantially less. chloride behaves in a similar way. Strongly acidic Extensive field experience confirms the favorable hydrochloric acid, however, is harmful to steel. conclusions of the study. Each of these substances is discussed under various conditions. 10 024 THE USE OF NICKEL STAINLESS STEELS AND NICKEL ALLOYS IN FLUE GAS Materials considered include high-nickel alloys, DESULPHURIZATION SYSTEMS IN THE UNITED stainless steels, high-molybdenum alloys, titanium, STATES zirconium and tantalum. By William L. Mathay, presented at Air Pollution 10 021 PROCUREMENT OF QUALITY STAINLESS Seminar, Buffalo, NY, U.S.A., Oct 1987. CASTINGS (4 pages) STEEL Performance of nickel-containing stainless steels and By Arthur H. Tuthill, reprinted from Tappi Journal, higher nickel alloys in the flue gas desulphurization Sep 1988. systems of 39 operating power units is reviewed and Quality stainless steel castings are readily available discussed. from foundries in the United States, Canada, Europe, Corrosion problems that have been encountered, Japan and elsewhere, provided the quality required is and the solutions to them, are presented. defined and specified in the procurement documents. Results indicate that the use of alloys in the more The low-carbon grades 0.03 per cent maximum are aggressive environments of various FGD systems is preferred. If the low-carbon grade is not listed in the finding increased favor. specification, a 0.03C maximum can be specified as an exception. 10 025 FLUE GAS DESULPHURIZATION; THE EUROPEAN SCENE Price is always a major consideration. The substantial reductions in maintenance, replacement, down- By W.H.D. Plant, presented at Air Pollution Seminar, time, and life-cycle costs, which normally follow from Buffalo, NY, U.S.A., Oct 1987. specifying the most appropriate composition, micro- Flue gas desulphurization is considered to provide a structure, and quality, need to be weighed against the significant contribution toward the avoidance of the extra cost of the higher quality obtained. problems associated with the formation of acid rain. Weld repair of minor defects found after solution Policies for alleviating acid-rain which have be- annealing can normally be done without reducing the come a major public issue in Europe and Scandinavia, corrosion resistance of the alloy, provided that the commanding high-level government attention-favor alloy is one of the low-carbon grades. programs of reduction of emissions of sulphur and nitrogen oxides enforced by the imposition of emis- 10 022 THE RESISTANCE OF STAINLESS STEEL, sion limits for large combustion plants. PARTLY EMBEDDED IN CONCRETE, TO CORROSION BY SEAWATER It is established that, with appropriate selection and application, the nickel materials are providing cost- By G.N. Flint and R.N. Cox, reprintedfromn Magazine effective solutions to corrosion problems in FGD of Concrete Research, Mar 1988. equipment, ensuring low maintenance costs with high Corrosion resistance of AISI 316 stainless steel- availability of equipment over the extended life of the partly embedded in concrete, partly exposed to stag- equipment-as demanded by conventional power sta- nant seawater, and partly exposed to seawater- has tion practice in Europe and North America. 13

10 026 FABRICATION AND METALLURGICAL cause of combinations of desirable physical and me- EXPERIENCE IN STAINLESS STEEL PROCESS chanical properties, including high strength at high VESSELS EXPOSED TO CORROSIVE AQUEOUS and low temperatures, toughness, corrosion resist- ENVIRONMENTS ance, controlled thermal expansion, workability and By George E. Moller and Richard E. Avery, presented at excellent spring properties. Air Pollution Seminar, Buffalo, NY, U.S.A., Oct 1987. The same outstanding combination of properties, Corrosion-resistant stainless steel structures, built for enhanced by several newly developed alloys and service in acidic and neutral chloride environments processing techniques, is used and is available to can have their inherent corrosion resistant properties today's designer of electronic components and sys- destroyed by fabrication and rolling mill defects. tems. Examples show degradation by carbon arc gouging, 10 030 NINE PER CENT NICKEL-28 YEARS OF weld attack, grinding, scratching with iron tools, splat- RELIABLE SERVICE IN LLQUEFIED NATURAL ter, heat tint, folds, paint, slag, seams and slivers. GAS CONTAINMENT (16 pages) Practices are discussed for the final shop and field repair of fabricated austenitic stainless steel equip- By William S. Mounce, 1989. ment, in AISI Types 316L and 904L, that has resulted A five-year multinational study sponsored by the Gas in unexpected localized attack. Research Institute, Chicago, showed in quantitative terms that 9% nickel steel has high resistance to the 10 027 WELDING AND FABRICATION IN NICKEL initiation and propagation of brittle fracture at liquid ALLOYS IN FGD SYSTEMS natural gas temperatures. By Richard E. Avery and W.H.D. Plant, presented at The GRI studies are reviewed for their practical Air Pollution Seminar, Buffalo, NY, U.S.A., Oct 1987. significance to designers and owners of liquefied Introduced is the range of nickel alloys commonly natural gas facilities, and are related to the unblem- employed in the fabrication of flue gas desulphurization ished record that the steel has compiled since the early equipment with the reference to the suitability of the 1960s in ship and storage tanks. various grades to withstand conditions experienced in A history of reliable cryogenic performance in service. facilities for handling liquid oxygen, nitrogen, argon Emphasis is placed upon the specification of grades and helium is discussed. and chemistry to meet requirements of performance in 10031 REPAIR WELDING HIGH-ALLOY FURNACE acid-chloride solutions with low pH levels. TUBES (3pages) Use of nickel alloys in new construction practices, and the ease of modification of repair, are described. By R.E. Avery and C.M. Schillmoller, reprinted from Alloy weldability is discussed in conjunction with Hydrocarbon Processing, Jan 1988. application of welding and quality assurance proce- One of the problems faced by operators of high tem- dures. perature reformer and pyrolysis furnaces is repair Fabrication, using to advantage the strength and welding of damaged furnace tubes that have been welding characteristic of the alloys, cost-effective exposed to elevated temperatures. Primary reason for design assembly, and utilization of clad or lined steel the difficulty lies in the high carbon content of the substrates are also covered. common centricast heat-resistant alloy tube materials, and others known for their superior high-temperature 10 028 SOFTENING HIGH-HARDENABILITY STEELS properties. FOR MACHINING AND COLD FORMING Recommendations are provided for successfully (13 pages) restoring ductility by solution annealing the base metal By D.V. Doane, reprinted from Journal of Heat prior to welding. Information is supplied on selection Treating, Vol. 6, (2), 1988. of welding filler metals and welding processes. High-hardenability steels are used for critical gearing, 10 032 PRACTICAL GUIDE TO USING 6Mo AUSTENITIC shafts, bearings and other machine components that STAINLESS STEEL (8 pages) are either cold formed or machined, or both, then subsequently hardened. ByRalphM. Davison andJames D. Redmond, reprinted from MaterialsPerfonnance, Dec 1988. Metallurgical factors affecting formability can be different from those affecting machinability. Conven- Gives information on the metallurgy, crevice corro- tional annealing may be adequate to soften certain sion, and chloride stress corrosion cracking resist- steels, but many grades require either subcritical or ance, design, and fabrication, as well as specifications intercritical annealing treatments to soften them suffi- and commercial product forms available for alloys ciently for machining or forming. 254 SMO, AL-6X, AL6XN, 1925 hMO (25-6MO), Summarized are data for carburizing steels, me- and 2OMo-6. dium carbon engineering steels, and high-carbon steels. Included are ASME boiler and pressure vessel code design stresses for temperatures up to 4270 C; ASTM 10 029 NICKEL ALLOYS IN TODAY'S ELECTRONICS specifications for product forms; and specific welding INDUSTRY (8 pages) filler metals and heat treatment requirements. By C.R. Isleib, given at 20th Annual Connectors 10033 NICKEL-CONTAINING ALLOY PIPING Interconnection TechnologySymposiun, Philadelphia, FOR OFFSHORE OIL AND GAS PRODUCTION pages) U.S.A., Oct 18-21, 1987. (21 By G.L. Swales and B. Todd, presented at the 28th Traditional nickel-containing alloys have played an Annual Conference of Metallurgists important role in electronic components. of the Canadian Institute of Mining and MetallurgyMeeting of Sea and Nickel and nickel alloy wire and strip are being used Science, Halifax, Nova Scotia, Aug 20-24, 1989. extensively in electrical and electronic devices be- 14

Considered are the technical (including fabrication) 10 037 STAINLESS STEEL IN ARCHITECTURE and economic factors influencing the choice of nickel- (16 pages) containing alloy piping - topside and subsea system By Bernard A. Smits, reprinted from Wilkes: applications (excluding downhole) in stainless steels EncyclopediaofArchitectuire: Design, engineering, (standard austenitic, duplex and high-alloy grades), and construction, Vol. 4, 1989. nickel-base alloys and cupronickels. Pointing out that there are more than 57 stainless 10 034 APPLICATIONS OF CENTRIFUGALLY-CAST steels recognized as standard alloys, in addition to ALLOY PIPING AND PIPE FITTINGS IN many proprietary alloys produced by different stain- ONSHORE AND OFFSHORE OIL AND GAS less steel producers, the article categorizes them - PRODUCTION (16 pages) austenitic, ferritic, martensitic - and gives the By G.L. Swales, presented at the 28th Annual representative properties of those used in architec- Conference ofMetallurgists of the Canadian Institute tural work. of Mining and Metallurgy Meeting ofSea andScience, Classification of stainless steel product forms, their Halifax, Nova Scotia, Aug 20-24, 1989. finishes and resistance to corrosion precedes sections devoted to forming, fabrication and cleaning. Petrochemical and oil refining companies have for many years been extensive users of centrifugally-cast 10 038 DEVELOPMENT OF ABRASION-RESISTANT, alloy pipe and tube while oil and gas production NICKEL-CONTAINING ALLOY WHITE IRONS sectors had made little use of them. OF HIGH HARDNESS (12 pages) But centricast heavy-wall alloy tubes and pipes By Dr. Gordon J. Cox, reprinted from American have been used to considerable economic benefit for Foundryinen'sSociety Transactions 1989. onshore flowlines, stainless subsea manifolds in duplex stainless steel, Christmas tree flow loops in It is suggested that the development and use of the martensitic stainless steel, and topside production and nickel-chromium Ni-Hard irons has been neglected test manifolds in medium nickel alloys. in recent years in favor of high-chromium irons An important development is production of inter- mainly because the latter have been made with a nally-clad steel pipe using centrifugal casting tech- high hardness and better fracture resistance. niques-cast carbon steel pipe with internal cladding New work is outlined in which it has been shown of UNS N 10276, S 31603, N 08825 and N 06625 that both Ni-Hard I and 4 can be produced with nickel-containing alloys. high hardness values of at least 700 Brinell and an associated excellent abrasion resistance. 10 035 SELECTION OF CORROSION-RESISTANT Both general classes of these abrasion-resistant ALLOY TUBULARS FOR OFFSHORE white irons have their best respective fields ofapplica- APPLICATIONS (8 pages) tion, but it is suggested that the benefits obtained from By C.M. Schillmoller, presented at the 21st Annual using nickel-bearing irons need now be reassessed. Offshore Technology Conference, Houston, TX, 10 039 STAINLESS STEEL SHEET LINING OF STEEL U.S.A., May 1-4, 1989. TANKS AND PRESSURE VESSELS (16 pages) High alloy stainless steels and nickel-base alloys offer By Richard E. Avery, Jonathan D. Harrington and great potential in revolutionizing well completion design William L. Mathay, 1989. by increasing allowable stress levels, removing corrosion inhibitor systems, and basically making it viable to The practice of lining - wallpapering - carbon operations not possible using conventional technology. steel vessels with stainless steel dates back to the In many offshore applications, corrosion-resistant late 1920s and was the first used by the chemical alloys can be economically justified as an alternate to industry, the oil industry following. carbon steel with continuous corrosion inhibition. Today almost every process industry uses linings where corrosion protection of carbon steel vessels 10 036 A FUNDAMENTAL STUDY OF CORROSION is needed. But the technique has lacked the precise RESISTANT ZINC-NICKEL ELECTROPLATING identification that this report gives it...along with (54 pages) capabilities and limitations, preparing for lining, By Dr. Kei Higashi, Yasunori Hayashi, Hisaaki procedures that include close examination of the Fukushima, Tetsuya Akiyama and Hideki Hagi, various welding techniques involved, inspection supported by a grant from the Nickel Development and testing, and post fabrication cleanup. Institute, Jan 1990. 10 040 THE RIGHT METAL FOR HEAT EXCHANGER Mechanical and chemical properties of metals are con- TUBES (5pages) siderably improved by alloying. Electrodeposition of By Arthur H. Tuthill, reprinted from Chemical alloys has aroused intense interest as a new technique that Engineering, Jan 1990. has greatindustrial possibilities forproducingcoatings of higher quality in the field of surface finishing. When designing a heat exchanger, the surface area From the early 1980s the number of reports on needed to carry the heat load is calculated, then the nickel-zinc alloys began to increase, the trend mainly design developed to meet heat exchanger standards resulting from research by steel manufacturers to and codes. Next come comparative cost estimates, develop highly corrosion-resistant alloy-plated steel factoring in knowledge from experience, and selec- sheet for automotive body panels. tion of the best tubing metal for the service. As a comprehensive knowledge of nickel-zinc al- Most unexpected failures of heat exchangers can loy plating is required to promote this highly corro- be traced to factors not fully taken into account sion-resistant alloy in other fields as well as in the when selecting tube materials - water quality, automotive industry, the authors conducted a series of character of the operation and maintenance, and studies and this reports their extensive findings. exchanger design. 15 10 041 NICKEL-CHROMIUM ALLOYS FOR ELECTRIC viewed, coated-steel systems also being included. RESISTANCE HEATING (15pages) Several new alloys are characterized as candidate By John E. Milne and Roger Giler, 1990. materials while galvanic compatibility is identified as the most critical consideration for marine fasteners. Materials for electric heating depend on an inherent resistance to the flow of electricity to generate heat Guidelines are presented to assist designers in the and the nickel-chromium alloys are widely used. selection of appropriate marine fastener materials. Specifically, this report looks closely at: alloys and 10 046 CLEANABILITY IN RELATION TO BACTERIAL properties; types of resistance elements; heaterdesign RETENTION ON UNUSED AND ABRADED concepts; terminals, leads and connections; how elec- DOMESTIC SINK MATERIALS (10 pages) tric resistance alloys work; effectof processing; nickel- By Dr. John T. Holah & R.H. Thorpe, reprinted from chromium alloy heating element design; failure The Journal of Applied Bacteriology, Aug 1990. analysis; and basic calculations. The relative cleanability of stainless steel, enamelled 10 042 STAINLESS STEEL FOR DURABILITY, FIRE- steel, mineral resin and polycarbonate domestic sink RESISTANCE AND SAFETY (8 pages) materials was assessed by comparing the number of By G. Waller and David J. Cochrane, 1990. organisms remaining on surfaces after cleaning. In unused condition all materials, other than one Fire tests and study of life-cycle costs together demon- enamelled strated that stainless steels are cost-effective materials. steel, were equally cleanable. Stainless They offer a greater degree of safety than glass- steel, abraded artificially or impact damaged to a similar reinforced plastic, aluminum or mild steel, galvanized degree as stainless steel subjected to domestic wear, retained approximately one log order or painted steels. less bacteria after cleaning than the other materials Compared with mild steel, lightweight stainless subjected to the same treatments. steel structures reduce topside weight of oil platforms. Materials that resist surface changes - stainless Additionally, they enhance fire resistance and vir- steel - will remain more hygienic when subjected to tually eliminate the need for maintenance. natural wear than materials that become more readily Maintenance onshore and offshore is costly, disrup- damaged, the report states. tive of production, and sometimes hazardous. The wide deployment of stainless steel will therefore yield 10 047 NICKEL ELECTROPLATING SOLUTIONS significant economic benefits as well as providing (5 pages) levels of fire safety unequalled by alternative meth- By Dr. S. Alec Watson, Dec 1990. ods, the studies showed. Discussed are basic principles and types of nickel 10 043 DESIGN, WATER FACTORS AFFECT SERVICE- solutions -Watts, solutions for hard nickel deposits; WATER PIPING MATERIALS (4 pages) solution for high throwing power; all-chloride solu- By Arthur H. Tuthill, reprinted from Power tions; nickel fluoborate, nickel sulphamate and other Engineering, Jul 1990. solutions. Plant requirements and the control of nickel plating The report identifies some of the principal factors that solutions are covered at length, and effluent treatment, affect the performance of piping used forcooling water. a specialized topic, is touched upon. Although several factors are interrelated, each is considered separately. This allows the engineer to use 10 048 ORGANIC ADDITION AGENTS FOR NICKEL the report as an engineering checklist to ensure that ELECTROPLATING SOLUTIONS (5pages) none of the major factors has been overlooked. By Dr. S. Alec Watson, Dec 1990. Studied are: carbon steel cement-lined piping and other coated steel piping types; nickel-containing stain- Most nickel plating, it is noted, is carried out in less steels; copper-nickel alloys and aluminum bronze; solutions based upon the Watts formulation to which and 6% molybdenum austenitic stainless steels and tita- organic chemicals have been added. For convenience, nium. the organic addition agents are usually divided into brighteners, stress reducers, levelling agents and wet- Factors that affect their behaviour are identified and ting agents according to their one of three ratings given. main function in the solution as designed by the solution formulator, but 10 044 PRACTICAL GUIDE TO USING DUPLEX most addition agents affect several properties of the STAINLESS STEELS (6 pages) nickel deposit. ByRalphM. DavisonandJamesD.Redmond,reprinted Many addition agents alter the structure of the from Materials Performance, Jan 1990. nickel and increase its hardness, and those that lead to incorporation of sulphur into the nickel increase its Duplex stainless steels are defined, and advantages of electrochemical activity. second-generation nitrogen-alloyed grades are explained. Organic addition agents form breakdown products Information is provided on duplex stainless steel met- in use, and when these accumulate in the solution they allurgy, pitting and crevice corrosion resistance, stress- must be removed in order to prevent deterioration in corrosion cracking resistance, specifications, mechanical the properties of the nickel deposits. Further quantities properties, fabrication procedures, and applications. of addition agents must be added at intervals to replace 10 045 PRACTICAL GUIDE TO USING MARINE the material consumed. For these reasons, control of FASTENERS (5pages) solutions containing organic additives is more involved than control of a plain Watts solution. By Ralph W. Ross Jr. and Arthur H. Tuthill, reprinted Brighteners, levelling and wetting agents are dis- from Materials Perfornance, Apr 1990. cussed, as are the effects of addition agents on cathode The marine corrosion resistance of copper-, iron-, efficiency, on corrosion resistance and on hardness. nickel-, and aluminum-based alloy fasteners is re- 16 10 049 ANODES FOR ELECTRODEPOSITION OF 10 052 NICKEL SULPHAMATE SOLUTIONS (5 pages) NICKEL (4 pages) By Dr. S. Alec Watson, Dec 1990. By. Dr. S. Alec Watson, Dec 1990. Nickel-plating solutions based upon nickel sulphamate During nickel electrodeposition, the anode provides are used mainly for electroforming purposes because electrical contact with the solution and distributes the the internal stress in the nickel deposits is lower than current to the work being plated. in deposits from Watts-type solutions. Also, higher In most cases, it is pointed out, the process uses deposition rates can be achieved. nickel metal anodes that dissolve as the current flows Some engineering nickel plating is done in sulphamate and thereby replace the nickel ions discharged at the solutions and they have been used for decorative plat- cathode, maintaining the concentration of nickel salts ing. These applications, however, usually use Watts- dissolved in the plating solution. type formations which, for the same nickel content, are Small insoluble anodes made of titanium with a thin about half the price of the sulphamate solutions. coating of platinum have been used in decorative plating solutions to augment the current from the main 10 053 ADDITIONS TO SULPHAMATE NICKEL soluble anodes arriving at deeply recessed areas. The SOLUTIONS (7pages) insoluble anodes were placed adjacent to the recesses By Dr. S. Alec Watson, Dec 1990. and supplied with current from a separate supply Additions to sulphamate nickel solutions are of two sufficient to increase the thickness of the nickel de- types: organic and metallic. The organic additives used posit within the recess to the required value. are stress reducers, hardening agents, levelling agents This technique suffers from three disadvantages: and wetting agents just as in the Watts solutions. The first, chlorine as well as oxygen can be evolved at the metallic additions are usually cobalt or manganese. anode and must be evacuated because it is toxic; There are circumstances where both are used. second, organic addition agents are consumed rapidly at the insoluble anode owing to its high potential; and 10 054 APPLICATIONS OF ELECTROFORMING third, the solution pH falls at the insoluble anodes (11 pages) owing to the discharge of hydroxyl ions - if the By Dr. S. Alec Watson, Dec 1990. currentthat passes tothe insoluble anodes is more than Electroforming is the production or reproduction of 2 or 3% of the total current, the overall pH of the articles by electrodeposition upon a mandrel or mold solution will fall, not rise, in use, thereby requiring that is subsequently separated from the deposit. This adjustment with inconvenient nickel carbonate or hy- separation is achieved by ensuring that the deposit is droxide instead of sulphuric acid. These disadvan- nonadherent from the commencement of deposition, tages can be overcome by the use of soluble anodes. or by using as the mandrel material a product that can Only soluble nickel anodes are considered further be melted out or dissolved away. here. A second important point concerning the substrate 10 050 APPLICATIONS OF DECORATIVE NICKEL preparation for electroforming, it is noted, is that the PLATING (7pages) form and surface finish applied to the mandrel are exactly copied on the inside surface of the electroform. By Dr. S. Alec Watson, Dec 1990. This high degree of precision is exploited in the Electrodeposited nickel plays the key role in several electroforming of record stampers, security printing decorative metal finishing systems where it is used in plates for producing bank notes, and electroformed combination with chromium, brass, silver, gold, and nickel products such as precision mirrors. lacquers. Since the nickel-chromium finish is the most widely 10 055 ELECTROLESS NICKEL COATINGS (10 pages) used and is also subjected to the most arduous condi- By Dr. S Alec Watson, Dec 1990. tions of service, a lot of attention has been given to the In essence an autocatalytic or electroless nickel solu- discovery of implementation of ways of ensuring tion contains a nickel salt plus reducing agent capable nickel chromium coatings having high durability. of reducing nickel ions to nickel metal. Hypophosphite This report covers the subject under headings of ions added as the sodium salt are the most common, it these finishes: nickel, nickel plus brass, nickel plus is pointed out, though borohydrides and aminoboranes silver, nickel plus gold, and nickel plus chromium. are also used to a lesser extent; these latter are not Also dealt with are the resistance to corrosion of considered further in this report. nickel-chromium, importance of nickel thickness, The use of hydrazine as a reducing agent to give copper undercoats, and double-layer or duplex nickel. pure nickel deposits has been suggested from time to 10 051 APPLICATIONS OF ENGINEERING NICKEL time but the unstable nature of hydrazine has given PLATING (7pages) ride to practical difficulties. Nearly all industrial electroless plating is done with By Dr. S. Alec Watson, Dec 1990. nickel plus hydrophosphite processes that are dis- For engineering applications, nickel electrodeposits are cussed in the report. applied for their physical and mechanical properties. Brightness and levelling are rarely needed. Also, nickel 10 056 PRACTICAL GUIDE TO HIGH-TEMPERATURE thickness is usually greater and engineering nickel coat- ALLOYS (10 pages) ings are often referred to as heavy nickel or thick nickel. By Peter Elliott, reprinted from Materials Performance, In both decorative and engineering plating, it is Aug 1990. stated, the objectives are the same: to upgrade a rela- High-temperature materials are used for many critical tively inexpensive basis metal by imparting to its sur- components in a numberof industries including power face the superior properties of the coating metal. In the generation, chemical processing, and gas turbine. With case of nickel, these properties include improved resist- ever-continuing demands for increased throughput ance to corrosion, erosion, scaling, fretting and wear. 17 and efficiency, there has been a trend towards higher All connectors share one function in common: to service temperatures and pressures. allow an electric current to pass across the connector This has resulted in continued corrosion problems, interface with as little electrical resistance, and conse- countered by continued improvements in material quently IFR heating, as possible. compositions, coating procedures and improved fabrication, notably casting, forging and welding. 10 061 DEVELOPMENT OF MECHANIZED FIELD GIRTH WELDING OF HIGH-ALLOY CORROSION- All these aspects are discussed. RESISTANT PIPELINE MATERIALS (10 pages) 10 057 SELECTION AND PERFORMANCE OF Summary of group sponsored research, by R.E. Avery STAINLESS STEELS AND OTHER NICKEL- and C.M. Schillmoller, 1991. BEARING ALLOYS IN SULPHURIC ACID For pipelines transporting petroleum products the se- (9 pages) lection of corrosion-resistant alloys is frequently justi- By C.M. Schillmoller, Dec 1990. fied in areas where severe corrosion is encountered. Sulphuric acid counts among the most important in- Successful welding of duplex stainless steels and dustrial chemicals. alloy-clad steels requires more care than conventional Although highly corrosive, concentrated sulphuric carbon steels in procedures development, operator acid at ambient temperatures is customarily handled in training and quality control. The economics of using carbon steel equipment. The aggressiveness of the corrosion-resistant alloys can be affected by the rate of acid varies with its concentration and temperature, welding, inspection and pipe laydown, particularly with its velocity relative to exposed surfaces, and with under difficult conditions. the nature of possible contaminants. Welding speed and efficiency can be increased Examined are the behaviour of several stainless using computer-controlled, automated girth welding. steel and nickel-bearing alloy compositions, taking Many improvements have been made in weld joint account of the variables enumerated. preparation, as well as a better root contour. Beginning with alloys suitable for equipment used in the manufacture of sulphuric acid and in the storage and 10 062 FRESH APPROACHES TO MOLD STEEL handling ofcold, concentrated commercially-pure acid, SELECTION (5pages) the text presents guidelines for the selection of corro- By F.T. Gerson, originally presented at the 1991 sion-resisting materials, including typical applications annual technical conference of the Society of Plastics that involve dilute, intermediate and strong acid. Engineers, Montreal. 10 058 HP-MODIFIED FURNACE TUBES FOR STEAM Despite the heavy investments in computer-aided de- REFORMERS AND STEAM CRACKERS (8 pages) sign, manufacturing and engineering which have per- mitted mold making for the plastics industry to advance By C.M. Schillmoller, Mar 1991. dramatically, alloy selection has largely been over- Covered are technical requirements and development looked by molders, fabricators, extruders and even by of specialty furnaces for steam methane reformers and mold makers themselves. ethylene pyrolysis and the reasons why HP-Modified New techniques, such as nickel vapour deposition alloys, in a period of intense competitive develop- to produce freeform shells for use as mold cavities, ment, have almost entirely displaced the formerly ac- and the selection of low thermal expansion alloys, will cepted HK-40 alloy. The technology has been tested. help reduce current barriers to progress, as mold users demand better material properties for their molds. 10 059 HP-MODIFIED FURNACE TUBE MARKET SURVEY (5 pages) 10 063 SELECTION AND USE OF STAINLESS STEELS By C.M. Schillmoller, Mar 1991. AND NICKEL-BEARING ALLOYS IN ORGANIC ACIDS (6 pages) Market facts and projections for centrifugally-cast high-alloy tube applications were compiled during By C. M. Schillmoller, 1992. 1988 and 1989. The corrosive action of organic acids is complicated Sources for the information included architect-en- because, as a rule, these acids are not handled in isolation gineering firms, furnace manufacturers, alloy produc- but as process mixtures with inorganic acids, organic ers, chemical, petrochemical and petroleum companies, solvents and salts. . .as well as in combination with other and industrial publications. organic acids. This controls the performance of the various alloys. Certain guidelines in alloy selection are 10 060 HIGH-PERFORMANCE NICKEL-CONTAINING presented for storage, handling and manufacture. CONNECTOR ALLOYS (14 pages) By Frank Emely, Apr 1991. 10 064 CLAD ENGINEERING (20 pages) Connectors and interconnections are the necessary links By L. M. Smith, Presented at The Offshore Technology tying together and rerouting electrical and electronic Conference, Houston, May 4-7, 1992. power, control, and signal movements between compo- Corrosion resistant alloy clad steel has been available nents and operational units in today's high technology in various forms for more than 40 years. It is being world of computers, communications, automobiles, air- used increasingly in the oil and gas industry. This craft, appliances and military and industrial equipment. publication describes methods of manufacturing and It is estimated that the United States automotive details of welding clad plate, pipe and fittings in the industry consumes more than 100 million terminals context of the specific requirements of this industrial daily with a double-digit growth rate. sector. It also provides information on existing appli- While many connections are permanent, including cations of clad products. soldered and crimp types, many are separable types that The publication concludes that there are successful allow the parts of the connection to bejoined, separated applications of clad steel worldwide using a wide and rejoined mechanically or manually as needed. variety of product forms and that there is considerable 18

experience in welding clad steel. For new projects, 10 069 EFFECT OF WIPING AND SPRAY WASH there is a wide choice of product types to suit most TEMPERATURE ON BACTERIAL RETENTION OF sizes and components so that clad steel is an obvious ABRADED DOMESTIC SINK SURFACE (4 pages) engineering option for corrosive production systems. By R. A. Stevens and J. T. Holah; Reprinted from The 10 065 APPLICATION OF IMPRESSED CURRENT Journal of Applied Bacteriology, Vol. 75, 1993. CATHODIC PROTECTION TO STAINLESS The relative cleanability of artificially abraded stainless STEEL HOT-WATER STORAGE TANKS steel, enamelled steel, mineral resin and polycarbonate (9 pages) domestic sinks was assessed by examining bacterial reten- By Tsukasa Shirouzu, 1992. tion after cleaning. Two cleaning regimes were used: the mechanical action of wiping combined with a spray-rinse, Class 1 pressure vessels made of stainless steel and used and spray-washing at a range of temperatures. as hot-water storage tanks in hotels, hospitals, factories and similar buildings are often thought to be free of 10 070 UNDERSTANDING AND PREVENTING CRACKS corrosion because they store fresh water. However, IN MOLD STEEL (5 pages) studies of past use have shown that corrosion and stress- By F. T. Gerson; Paper presented at the Annual corrosion cracking occur in crevices and welds. Repairs Technical Conference of the Society of Plastics are seldom satisfactory and, although the cathodic pro- Engineers, New Orleans, LA, 1993. tection method is effective, it is seldom used. mold- This report investigates the optimum condition of In order to build precise and reliable products, makers require that the cavity steel they use not crack. cathodic protection for S 30408 stainless steel tanks in the anticipated corrosion environment and studies the This paper examines the types and causes of cracks in application of an impressed current cathodic protection. alloy steel molds, the role of mold-steel selection in preventing such cracks and a new, inexpensive and The report finds that even this type of stainless steel, disarmingly simple technique that helps guard against which is in general use today, can, through suitable their occurrence. cathodic protection, be a material with superior durability. Proper cathodic protection, however, requires 10 071 WROUGHT AND CAST HEAT RESISTANT that attention be given to electrode positioning and STAINLESS STEELS AND NICKEL ALLOYS FOR tank structure for uniform distribution of potential. THE REFINING AND PETROCHEMICAL INDUSTRIES (1995) 10 066 PREVENTING STRESS-CORROSION CRACKING OF AUSTENITIC STAINLESS STEELS IN By D.J. Tillack and J.E. Guthrie. CHEMICAL PLANTS (9 pages) A wide variety of iron and nickel-based materials are By Masao Nakahara, 1992. used for pressure vessels, piping, fittings, valves and otherequipment in refineries and petrochemical plants. This report discusses stress corrosion cracking, SCC, that Some of the more important of those applications at occurs with stainless steels in chemical plants. It focuses temperatures below 650'C (1200'F) will be discussed, on SCC caused by chlorides and how to prevent it. however, the emphasis of this document is on applica- 10 067 EVALUATION OF DECOMMISSIONED LNG tions of heat resistant alloys above this temperature. STORAGE TANKS AT CHULA VISTA, CA By James P. Lewis and Ted A. Williams; presented at 10 073 SELECTION GUIDELINES FOR CORROSION the American Gas Association Distribution! RESISTANT ALLOYS IN THE OIL AND GAS Transmission Conference, April 1991. INDUSTRY (1995) San Diego Gas & Electric built two of the first LNG By Bruce D. Craig peak shaving plants in the United States. These plants Theselectionofcorrosionresistantalloys forproducing which were located on a common facility near their and transporting corrosive oil and gas can be a complex SouthBaypowerplantinChulaVista,Califomia, went procedure and if improperly carried out can lead to into service in 1965 and 1970. They were both mistakes in application and misunderstanding about the decommissioned in 1985 and dismantled in 1990. This performance of a CRA in a specific service environment. paper describes the findings during the dismantling. A group of alloys, based on information available, is selected that represents a possible range of alterna- 10 068 SPECIFYING STAINLESS STEEL SURFACE tives. Sometimes the time to carry out this work can TREATMENTS (5pages) easily require 1-3 years and considerable expense. By Arthur H. Tuthill and Richard E .Avery, Reprinted from Advanced Materials & Processes, Vol. 142 (6), 10 074 THE CORROSION RESISTANCE OF NICKEL- 1992. CONTAINING ALLOYS IN HYDROFLUORIC ACID, HYDROGEN FLUORIDE, AND FLUORINE (1995) This paper discusses various stainless steel surface treatments: passivation, pickling, electropolishing, By C. M. Schillmoller and mechanical cleaning. Also discussed are condi- This brochure illustrates some of the corrosion expe- tions which would favor one method over another riences involved in handling hydrofluoric acid (HF) depending on the application. Often the surface and anhydrous hydrogen fluoride (AHF) as well as the treatment chosen can determine the success of the handling of fluorine. stainless steel being used. Although HF is chemically classified as a weaker acid than hydrochloric or sulphuric acids, few compounds are more corrosive. In many aqueous applications, gold, platinum, Alloy 400 and Alloy C-276 are the only materials adequately resistant to attack for useful long-term service. 19

10 075 SELECTION AND USE OF STAINLESS STEELS 10 079 EFFECTIVENESS OF SANITATION WITH AND NICKEL BEARING ALLOYS IN QUATERNARY AMMONIUM COMPOUND OR NITRIC ACID (1995) CHLORINE ON STAINLESS STEEL AND OTHER C. M. Schillmoller DOMESTIC FOOD-PREPARATION SURFACES (5 pages) Even though most stainless steels do not resist 100% By Joseph F. Frank and Revis A.N. Chmielewski, HN03, they are resistant to corrosion by the 60% to 70% concentrations that result from ammonia/air oxi- Reprinted from Journalof Food Protection, Vol. 60 dation processes, and the low-carbon or stabilized (1), January, 1997. stainless steels play a major role in the production and Surface materials tested included mechanically pol- handling of nitric acid over a wide range of tempera- ished (type 304, #4 finish) and electropolished stain- tures and concentrations. less steel, polycarbonate, and mineral resin. Surfaces This article examines the selection criteria for sev- were prepared for testing by allowing attachment of a eral stainless steels and nickel-bearing alloys in the Staphylococcus aureus culture for 4 h to achieve an production and handling of nitric acid and in its use, initial attached population of 104 to 105 CFU/cm2 . both in the production of ammonium nitrate fertilizers Results indicated that the stainless steels and the and as an acid mixture with HF for descaling. smooth polycarbonate, which had 0.5 log CFU/cm2 or fewer of residual staphylococci, were more readily 10 076 GUIDELINES FOR THE USE OF STAINLESS sanitized by quaternary ammonium compound than STEEL IN MUNICIPAL WASTE WATER were either the mineral resin surfaces, which had TREATMENT PLANTS (1995) nearly 2.0 log CFU/cm2 of residual staphylococci, or By Arthur H. Tuthill and S. Lamb the abraded polycarbonate which had nearly 1.0 log 2 Stainless steel piping has become a standard material CFU/cm of residual staphylococci. of construction for municipal waste water treatment 10 080 CLEANING STAINLESS STEEL SURFACES plants built in the United States over the past 25 years. PRIOR TO SANITARY SERVICE (12 pages) Since the late 1960s, over 1600 municipal waste water treatment plants have been built with stainless steel By A.H. Tuthill, R.E. Avery and R.A. Covert, reprinted aeration piping, transfer piping for digester gas and from Dairy, FoodandEnvironmental Sanitation, Vol. sludge, sliding gates, valves, tanks, screens, hand 17, No. 11, November 1997. rails, and other equipment. Stainless steel was selected This article describes practical procedures for clean- originally over galvanized and painted carbon steel to ing stainless steel surfaces for use in the dairy, other reduce the higher maintenance and replacement cost food and beverage, pharmaceutical, and similar indus- associated with these less corrosion-resistant materials. tries. Types of surface contamination that might oc- Overall experience has been good to excellent. cur, along with their prevention and removal are included. Also mentioned are various steps to be taken 10 077 STAINLESS STEELS FOR BIOPROCESSING to obtain clean surfaces initially. (1994) By C. P. Dillon, D. W. Rahoi, A. H. Tuthill 10 081 PROPERTIES AND APPLICATIONS OF ELECTROLESS NICKEL (37pages, 1997) Stainless steel equipment has a long history of successful use in bioprocessing operations for which By Ron Parkinson high-quality surface finishes, cleanliness, and mainte- The important properties of electroless nickel deposits nance of sanitary conditions are essential. Stainless are described and examples given of how these prop- steels are widely available, corrosion resistant, eco- erties have been used successfully to solve materials nomic, and easy to fabricate; they are uniquely quali- problems in various industries. Through presentation fied as construction materials for equipment and of this information, it is anticipated that new opportu- systems in the bioprocessing industries. nities for the use of electroless nickel coating will become apparent to those not already familiar with 10 078 ELECTROPLATING ON PLASTICS (9 pages, 1995) their broad range of properties, thereby promoting By Ron Parkinson and Tony Hart growth within the industry. Electroplating and electroforming typically account 10 082 IS "NICKEL" SAFE? A TOXICOLOGY PRIMER for 9 to 11 % of total nickel consumption. (16 pages) The substrates on which nickel is electroplated vary widely. Steel is the most common but others By Bruce R. Conard, reprinted from The Proceedings included copper, brass, stainless steel, zinc, aluminum of the Nickel-Cobalt 97 International Symposium, and plastics. Vol. III, August 1997. This publication presents a historical review of the The environmental and human health risks posed by industry and describes its present status and future expec- certain chemical substances are very real and must be tations. It also describes the technical progress that has assessed and managed to prevent harm. In the case of been responsible for the improved performance and metallic elements such as nickel, however, there is a acceptance of plated plastics. The size of the market and tendency by the public and regulators to incorrectly growth forecasts are discussed and related to total nickel oversimplify and misrepresent toxicological informa- consumption in the electroplating industry. tion by assigning the same toxicity to all compounds containing the metal. As a result, many people errone- ously think "nickel" (meaning all forms and compounds of nickel) is dangerous to the environment and is a threat to human health. This paper provides an overview of the animal and human health studies that exist which indicate that some specific compounds of nickel must be carefully managed, but that the major- 20

ity of nickel compounds and the metallic form itself of industry with nickel-containing alloys and competi- (including alloys) show little or no evidence of tive materials - which materials work, what materials causing adverse health effects. Gaps in knowledge others have used successfully, the economics invloved, and specific research programs underway in this the comparative properties and possible problem areas. field will be discussed. Summarized in concise and useful form are major presentations made in the workshops so that the data 10 083 CORROSION PERFORMANCE OF Ni-Cr-Fe and background information are readily available in ALLOYS IN GEOTHERMAL HYPERSALINE handbook form. BRINES (7pages, 1998) By R.H. Moeller and C.J. Cron 11 002 NICKEL ALLOYS FOR ELECTRONICS (126pages) A large scale corrosion test was designed to find the Nickel Development Institute reference book series, most cost effective alloys for completing the Salton 1987. Sea geothermal resource wells. A series of Ni-Cr-Mo Reliability, freedom from maintenance costs, longer alloys were tested over several years in three produc- service and minimum production rejects are increas- tion wells and two injection wells. The various alloys ingly important to designers and manufacturers of were made into 8 5/8in. (22 cm) outside diameter by electronic and electric equipment. 0.400 in (1.0 cm) wall production casing strings about Detailed information is provided forengineers that is 1500 ft. (457 m) long. The well bore was divided into directly applicable in evaluating and applying the nickel three temperature regimes and several joints of each alloys that are most useful to the electronics industry. alloy were tested in each regime. This paper discusses the corrosion effects of the brine on the various alloys 11 003 GUIDELINES FOR SELECTION OF NICKEL for lengthy periods under actual flowing conditions. STAINLESS STEELS FOR MARINE Long term corrosion tests were also conducted on ENVIRONMENTS, NATURAL WATERS AND alloys considered for injection tubing. BRINES (45pages) Nickel Development Institute reference book series, 10 084 ELECTROFORMING - A UNIQUE METAL 1987. FABRICATION PROCESS (11 pages, 1998) Engineers usually begin with a good idea of the By Ron Parkinson alloys that will meet the stresses and mechanical Electroforming plays an important role in our daily requirements of the assembly under consideration. lives. We have contact with it many times each day and Information provided allows them to take the next it greatly enhances our lifestyle in a variety of ways. In step, to make reasonable preliminary estimates of the addition, it is an extremely versatile process. It is used manner in which the environment is likely to affect to produce micro components for the medical and performance of the materials considered. electronics industries and huge components for the aircraft and aerospace industries. For many applica- 11 004 MATERIALS FOR SALINE WATER, tions it has become indispensable and yet outside the DESALINATION AND OILFIELD BRINE PUMPS electroforming community, little appears to be known (25 pages) about the process and its applications. Most metallur- Nickel Development Institute reference book series, gists, engineers and designers are not well informed on 2nd ed., 1994. the subject as it is rarely, if ever, included in technical Materials for saline water pumps include cast irons, courses presented at colleges or universities. Neverthe- austenitic cast irons, copper alloys, nickel-base al- less, it is a unique metal fabrication process and nickel loys and stainless steels. is the dominant metal in this industry. In selecting corrosion-resisting materials for the 10 085 MICROBIOLOGICALLY INFLUENCED several components of saline water pumps there are CORROSION OF STAINLESS STEELS BY fourprincipal considerations: corrosion resistance in WATER USED FOR COOLING AND clean seawater, and in modified saline waters that HYDROSTATIC TESTING (13 pages, 1997) pumps commonly encounter; resistance to high velocity and turbulence; resistance to stagnant saline By G. Kobrin et al., originally presented at the 581h water encountered during standby periods; and gal- Annual InternationalWater Conference, November vanic compatibility: the pump case should galvani- 3-5, 1997, Pittsburgh, PA. cally protect the internals. Case histories from experience and the published litera- These considerations are addressed, as is experi- ture illustrate factors which resulted in microbiologi- ence with available alloys. cally influencedcorrosion (MIC)of stainless steel piping, storage tanks and heat exchangers by waters used for 11 005 MODERN CARBURIZED NICKEL ALLOY STEEL hydrotesting, cooling and other purposes. Practices (86 pages) which will prevent or reduce potential for MIC, includ- Nickel Development Institute reference book series, ing material substitution, are discussed, along with 1990. efforts to heighten awareness of the problem. Summarized are the fundamental properties of carburized steel which achieves superior performance 11 001 MATERIALS ENGINEERING WORKSHOP, because of its unique composite structure. PROCEEDINGS (121 pages) The high-carbon surface layer interacts with the Nickel Development Institute reference book series, low-carbon core during subsequent heat treatment to 2nd ed., 1994. provide desirable residual compressive stresses in A continuing series of materials engineering work- the surface layer to resist imposed loads in service. shops is conducted by experts retained by the Institute. Data are provided on the properties of carburized Applications oriented, they review the experiences nickel alloy steels. And processing techniques to improve productivity are suggested to aid the materials 21 engineer in selecting steel grades and processing se- since 1989. Contents include chapters on: Fundamentals quences to meet stringent design and service require- of corrosion; Nickel-containing alloys in service water ments. systems; Applications in seawater systems, pumps and valves; Factors affecting the life of stainless steel and 11 006 NICKEL IN POWDER METALLURGY STEELS (42 nickel-based alloy expansion joints in steam service; pages) Application of nickel-containing alloys in air pollution By D.V. Doane and Dr. M. Semchyshen, 1991. control systems; Welding of scrubber materials; and With the improvements available in ferrous metal pow- Guidelines for the welded fabrication of nickel-contain- ders and the advances in processing, powder metallurgy ing stainless steels for corrosion resistant services. steel has joined the ranks of engineered materials and 11 012 GUIDELINES FOR THE WELDED FABRICATION should be considered by designers, materials engineers OF NICKEL ALLOYS FOR CORROSION- and process engineers for many new applications that RESISTANT SERVICE (35 pages) require controlled material properties. The handbook summarizes the status of nickel- By Richard E. Avery and Arthur H. Tuthill, 1994. alloyed ferrous powder compacts. Indicated are prop- This publication is presented in three parts with each, in erties that can be achieved at various densities and turn, focused toward the primary interests of the welder, with various compositions and heat treatments. the materials engineer, and the design engineer. Part I, FOR THE WELDER, assumes that the weld-ers 11 007 GUIDELINES FOR THE WELDED FABRICATION and others involved in welded fabrication are familiar with OF NICKEL-CONTAINING STAINLESS STEELS the basic techniques used in carbon steel fabrication and FOR CORROSION-RESISTANT SERVICES have had limited experience with nickel alloys. (46 pages) Part 11, FOR THE MATERIALS ENGINEER, de- By R. E. Avery and A.H. Tuthill, 1992. scribes the types of nickel alloys; it reviews how their Widely specified for applications where corrosion metallurgical and corrosion characteristics are affected resistance is required, stainless steels are an excellent by welding and covers some of the more specialized choice for chemical, dairy, food, architectural, bio- aspects of fabrication such as heat treating. technology equipment and similar services. Part m, FOR THE DESIGN ENGINEER, provides a This publication is presented in three sections: "For the number of design examples showing how the corrosion welder," deals with the differences in welding techniques performance of nickel alloys used in process tanks can be for nickel-containing stainless steels, versus conventional enhanced through thoughtful design. carbon steels; "For the materials engineer," describes 11 013 STAINLESS STEEL IN ARCHITECTURE, BUILDING various types of stainless steels and how their metallurgi- AND CONSTRUCTION - GUIDELINES FOR cal and corrosion resistant characteristics are affected by ROOFS, FLOORS AND HANDRAILS (16pages) welding and heat treating; and, "Forthe design engineer," which demonstrates how the corrosion performance of By D. J. Cochrane, 1994. stainless steels can be enhanced by good design. The unique properties of stainless steel are ideally suited for roofing, whether flat, pitched, arched or 11 008 MACHINING NICKEL ALLOYS (22 pages) curved, floors and interior/exterior handrails, balus- Reference book, prepared for the Nickel Development trades and staircases. Institute by Technical Marketing Resources, Inc., 1992. 11 014 STAINLESS STEEL IN ARCHITECTURE, BUILDING AND CONSTRUCTION - GUIDELINES FOR An overview is provided on machining nickel alloys MAINTENANCE AND CLEANING (8pages) using traditional methods, and the advances that have been made are described. By P. G. Stone, 1994. For over half a century, stainless steel has provided 11 010 NICKEL-CONTAINING MATERIALS FOR WATER architects with the means to produce a permanent CONTROL APPLICATIONS (30 pages) expression of their design concepts. This visual per- By Richard E. Avery and Arthur H. Tuthill, 1993. manency is due to the material's excellent resistance to Nickel-containing materials have established themselves corrosion allowing the surface to retain its original in difficult water control environments such as locks, appearance indefinitely. dams and hydroelectric plants by demonstrating years of However, like any other building material, stainless economical and trouble-free performance. Data com- steel may become soiled in service by the deposition piled from measurements taken at field sites is presented of airborne dirt, by accidental damage or through acts in this publication togetherwith the physical properties of of vandalism. the materials in use. Satisfactory service, substantiated This brochure provides guidance on cleaning tech- by evaluations made as much as twenty-six years after niques that are appropriate for typical service situations. project completion, afford a basis for improving existing Some aspects of design that can simplify cleaning and structures in which lower grade materials are giving less minimise maintenance costs are also indicated. than satisfactory service. The results support the use of various types of nickel-containing materials in new, 11 015 STAINLESS STEEL IN ARCHITECTURE, advanced designs. BUILDING AND CONSTRUCTION - GUIDELINES FOR BUILDING EXTERIORS (10 pages) 11 011 MATERIALS WORKSHOP FOR THE POWER By P. G. Stone, 1994. INDUSTRY, PROCEEDINGS (93 pages) Throughout the world, architecture is recognised as Nickel Development Institute reference book, 1993. one of the greatest arts of any civilisation and, like all This publication summarizes the major presentations art forms, it responds to cultural and technological made in more than 70 power industry materials work- changes within society. shops sponsored by the Nickel Development Institute At first, stainless steel was mainly used for pres- 22

tigious applications. Since then, however, the 12 001 LIFE-CYCLE COST BENEFITS OF continu-ous invention of new ways to make stain- CONSTRUCTING AN FGD SYSTEM WITH less steel has both dramatically reduced its cost, in SELECTED STAINLESS STEELS AND NICKEL- real terms, and expanded the range of products BASE ALLOYS (23 pages) available. Consequently, stainless steel's combina- Report published by PEI Associates, Inc. for the tion of proven performance and cost effectiveness is Nickel Development Institute and the American Iron now being exploited, in mundane as well as prestig- and Steel Institute, 1987. ious applications. Life-cycle cost analyses of the use of stainless steels and 11 016 DIRECTORY OF NORTH AMERICAN SUPPLIERS corrosion-resistant alloys were compared with those of OF STAINLESS STEEL PRODUCTS FOR nonmetallic lined-carbon steel in the construction of BUILDING AND CONSTRUCTION flue gas desulphurization system scrubbers. (2nd edition, 31 pages, 1996) It was found that the life-cycle cost of the corrosion- The information contained in this directory has been resistant alloys are often substantially less than the costs prepared for the general information of the reader for nonmetallic-lined steel. The benefits of using better based on information obtained or otherwise available materials of construction are improved reliability and to NiDI. Anyone that produces, fabricates, installs or reduced downtime; even a minor improvement in these distributes stainless steel building and construction areas can add substantially to the life-cycle cost savings. products is encouraged to submit information de- Additional savings can be achieved by selecting scribing their products or services for possible inclu- materials for individual components in order to match sion in future editions of this directory. the operating environment of the component with the characteristics of the materials. 11 017 NI-HARD MATERIAL DATA AND APPLICATIONS Extensive field experience confirms the favourable (28 pages) conclusions of the cost analyses. By K. Rbhrig, 1996. 12 002 PERFORMANCE OF TUBULAR ALLOY HEAT For over half a century, Ni-Hard has been the number EXCHANGERS IN SEAWATER SERVICE IN THE one choice for industrial processes demanding ex- CHEMICAL PROCESS treme abrasion resistance. Its well-proven, low-cost INDUSTRIES (124 pages) characteristics has seen it used in mining, power, Manual, published by Materials Technical Institute of cement, ceramic, paint, dredging, coal-coke, steel and the Chemical Process Industries, and the Nickel foundry industries. As grinding balls, mill liners, Development Institute, 1987. pulverizer rings and roll heads, slurry pump parts, Although there is much information available on cor- pipes and elbows, wearbacks and metalworking roles rosion of metals and alloys by seawater, relatively -the range of properties inherent in the different grades little has been written about specific equipment in of Ni-Hard have made it a world-wide success. seawater service. This book updates information for users on Ni-Hard's Intended to serve as a practical, easily usable desktop material data and applications. reference for the needs of engineering, operations and maintenance personnel, the manual gives information 11 018 PROPERTIES AND APPLICATIONS OF NI- on materials selection for- and design, operation and RESIST AND DUCTILE NI-RESIST ALLOYS maintenance of - tubular alloy heat exchangers in (38 pages) seawater service in the chemical industries. By Roger Covert, et al, 1998. It will also serve as an educational resource for new Ni-Resist austenitic alloy irons offer an outstanding materials and corrosion engineers engaged in process combination of properties to meet a variety of indus- design and plant assistance. trial demands in withstanding the effects of corrosion, heat and wear. Provides comparative data on the 12 003 GUIDELINES FOR THE USE OF COPPER various grades of Ni-Resist including physical and ALLOYS IN SEAWATER (11 pages) mechanical properties, welding and heat-treatment By Arthur H. Tuthill, reprinted from Materials procedures, and other data to assist in their specifica- Performance, Vol. 26, (9), 1987, by Nickel tion. Provides typical applications for the various Development Institute and Copper Development commercial grades. Association. Guidelines allow engineers to make reasonable esti- 11 019 STAINLESS STEEL PLUMBING (8 pages) mates of effect of environment on copper alloys per- NickelDevelopmentlnstitutereferencebookseries, 1997. formance. Charts and summaries provide useful Today stainless steels are used more and more in guideposts, it is noted, but they do not replace experi- potable water systems. ence, specific data, or properly conducted evaluations The information in this booklet is tailored for design- for successful use of materials. ers, plumbers, end-users, maintenance engineers and 12 004 ANSWERS FOR ARCHITECTS WHO DESIGN others interested in providing reliable potable water FOR BEAUTY, PERFORMANCE, UTILITY AND systems. It covers: the nature of stainless steel; cor- PRESTIGE WITH NICKEL STAINLESS STEEL rosion resistance; disinfection of stainless steel; tub- (60 pages) ing standards; fittings; fabrication and handling. Produced by the Nickel Development Institute on behalf of members of the European Stainless Steel Development and Information Group, 1988. Although available in English, French, German, Ital- ian and Spanish editions, unless a specific language is requested, it will be presumed thatEnglish is preferred. Architects and engineers taking advantage of nickel 23 containing stainless steel's unique combination of 12 009 ADVANTAGES FOR ARCHITECTS WHO DESIGN properties have found it to be a versatile material, FOR BEAUTY, PERMANENCE, UTILITY AND eminently suited for numerous building and construc- PRESTIGE WITH NICKEL-CONTAINING tional applications. STAINLESS STEEL; AN ARCHITECT'S GUIDE Many of these uses are covered in text and color ON CORROSION RESISTANCE (32 pages) photographs from around the world and include building Produced by the Nickel Development Institute on faqades, roofing, windows and doors, entrances, street behalf of members of the European Stainless Steel furniture, interiors, general applications and sculptures. Development and Information Group, 1990. 12 005 A REPORT ON THE PERFORMANCE OF Stainless steel has been used to practical advantage in STAINLESS STEEL PIPE FOR WATER SUPPLY architecture for many years. It provides bright reflec- IN UNDERGROUND SOIL ENVIRONMENTS tive surfaces which are both attractive and functional (66 pages) when used as a complete facade or in conjunction with Two-volume report, published by Japan Stainless Steel glass and other materials. Notable examples are the Association, and the Nickel DevelopmentInstitute, 1988. Chrysler Building in New York and the Savoy Hotel Contains extensive corrosion data and color photo- in London whose clean, bright appearance after more graphs on nickel-containing stainless steel, carbon than 50 years exposure to polluted city air is strong steel, copper and lead pipes tested in 25 widely- tribute to the lasting, cost-effective quality of stainless separated geographic locations in Japan. steel. This publication offers basic guidelines on the advantages for architects designing with stainless steel 12 006 TECHNICAL MANUAL FOR THE DESIGN AND including: selecting the most suitable grades for spe- CONSTRUCTION OF ROOFS OF STAINLESS cific locations; design, fabrication, surface finish and STEEL SHEET (110 pages) maintenance factors; retention of strength after long This English edition - prepared as a joint project of exposure to atmospheric corrosion; and details of the Nickel Development Institute and the Japan atmospheric corrosion tests. It also describes grades of Stainless Steel Association-isbasedon the Technical stainless steel and explains types of corrosion. Manualfor the Design and Construction of Roofs of Stainless Steel Sheet, published by JSSA in 1985. 12 010 STAINLESS STEEL IN SWIMMING POOL BUILDINGS (16pages) It comments on processes in use in Japan for welding stainless steel, and also covers topics ranging from Prepared by the Nickel Development Institute, in elementary facts about stainless steel to a practical association with the Sports Council, Stainless Steel commentary on structural methods and construction, Advisory Centre, Building Research Establishment, taking into account the climate and construction tech- Institute of Sport & Recreation Management, and nology of Japan. Pool Water Treatment Advisory Group, 1995. Stainless steels are well established as corrosion resistant 12 007 COPPER-NICKEL ALLOYS - PROPERTIES materials for many items used in building and equipping AND APPLICATIONS (28 pages) swimming pools. For decades, stainless steels have had Published by Copper Development Association, in co- an excellent track record-typically specified for equip- operation with the Nickel Development Institute, 1982. ment in the pool water (ladders, wave machine grilles, Copper has excellent resistance to corrosion in the etc.), and in environmental engineering plant control atmosphere and in fresh water. The addition of nickel boxes, air handling equipment, fire dampers, etc. to copper improves its strength and durability and also This guide gives practical advice on the successful its resistance to corrosion, erosion and cavitation in all use of stainless steel. It is aimed at architects, design- natural waters, including seawater andbrackish,treated ers, builders and pool managers. or polluted waters. The added advantage of resistance 12 011 DESIGN MANUAL FOR STRUCTURAL to biofouling makes the material ideal for applications STAINLESS STEEL (114 pages) in marine and chemical environments such as ships' hulls, desalination plants, heat exchange equipment, Sponsored by the Nickel Development Institute on seawater and hydraulic pipelines, oil rigs and plat- behalf of the members of the European Stainless Steel forms, fish farming and water handling equipment. Development and Information Group, 1994. This publication discusses typical applications for The contents of this manual relate to an in-depth study copper-nickel alloys and their selection. carried out by the Steel Construction Institute on the 12 008 PIPING MANUAL FOR STAINLESS STEEL structural application of stainless steel foronshore and PIPES FOR BUILDINGS (235pages) offshore structures. Expediency dictated that the project would examine three grades of material only Published by Japan Stainless Steel Association and namely austenitic grades 304L and 316L, and a high the Nickel Development Institute, 1987. strength austenitic-ferritic grade commonly known as This updated report produced by the Japan Stainless Duplex 2205. Steel Association details the successful use of stain- It should be emphasised that this does not however less steel piping for water delivery systems for build- preclude the use of standard 304 and 316 grades or other ings in Japan. The manual covers design, construction austenitic grades that designers and manufacturers and maintenance and provides extensive reference specify provided that the 0.2% proof strength and the information of standards, properties, corrosion and ultimate strength are not lower. In general, 'L' grades other topics. are selected for highly aggressive corrosion conditions to avoid intergranular corrosion from occurring, however, since modem stainless steels contain carbon levels of 0.05% and lower, this phenomena is rarely encountered on thicknesses of material up to 16mm. 24

13 001 ZINC-NICKEL ALLOY ELECTROPLATED STEEL 13 006 DEVELOPMENT OF STAINLESS STEEL COIL AND OTHER PRECOATED COIL FOR USE RAILROAD CARS IN JAPAN (48 pages) BY THE AUTOMOTIVE INDUSTRY: A REVIEW OF By Iseo Hatono, 1992. LITERATURE PUBLISHED 1983 TO 1987 (43 pages) Described is nickel-containing stainless steel in Japa- nese railroad car design and production, and its con- By Dr. S.A. Watson, 1988. sumption. A great deal has been published on the results of fundamental research, applied research and the in- 13 007 FLUE GAS DESULFURIZATION IN JAPAN dustrial development of zinc-alloy electrocoated (30 pages) steels, especially for the automobile manufacturing By Shigeru Morita, 1992. industry. Reviewed are the current state of flue gas One hundred-thirty papers, patents and technical desulphurization in Japan and recent trends in the use of articles were methodically reviewed with the objec- nickel-containing stainless steel and corrosion-resistant tive of obtaining a clear picture, particularly of the nickel alloys in flue gas desulphurization plants. relative merits of zinc-nickel and zinc-iron electrocoated steels. 14 001 HIGH-PERFORMANCE ALLOYS: HOW THEY Comparison of the published findings under eight ARE USED OFFSHORE (6 pages) headings allowed 12 conclusions, favorable toward By C.M. Schillmoller, reprinted from World Oil, 1988. zinc-nickel, to be drawn. Stainless steels and nickel-base alloys are increasingly utilized in the oil and gas industry for exploita- 13 002 DEMAND TRENDS FOR NICKEL AND NICKEL- tion of sour crudes. CONTAINING MATERIALS USED IN THE Traditionally, nickel-alloys and copper-nickel al- JAPANESE ELECTRONICS INDUSTRY loys have served the industry well for sucker rods, (125 pages) instrumentation, packers, valves for gas lift, By A. Nakamura and T. Ishidate, 1989. pumpshafts, seawater piping, heat exchange tubing Reviewed are: the Japanese electronics industry's and other critical components. growth and status; the trend of nickel uses in the New generation platforms, deep sour gas wells, industry, traditional and newly developed; and future carbon dioxide-enhanced oil recovery projects, and annual growth rate. production in the Arctic, all now make use of the specialty chromium-nickel-molybdenum stainless steels and the nickel-chromium-molybdenum alloys 13 003 DEVELOPMENT OF RESIN-COATED STAINLESS in extremely severe corrosive applications. STEEL IN JAPAN (30 pages) Examples are cited and an economic analysis pro- By M. Yoshino, 1990. vided, as well as several suggestions for reducing the weight of platforms' topside construction, and guide- An opportunity developed for applying thin-gauge lines provided for selection of alloys to reliably resist stainless steel to exterior roofs and side walls of the aggressive corrosive environments. residences and factories in Japan. Resin-coated (nickel-containing) stainless steel, RCSS, was the 14 002 WHY ZINC-NICKEL COATED STEELS? (2 pages) answer. By Dr. S.A. Watson, reprintedfrom Nickel, Vol.4 (), This review discusses RCSS substrate, resin paint, 1988. resin coating process, properties of RCSS, weldable and transparent RCSS. A great deal has been published on the results of fundamental research, applied research and the industrial development of the zinc-alloy electrocoated steels. 13 004 STAINLESS STEEL DEMAND FOR KITCHEN The Nickel Development Institute reviewed in- EQUIPMENT IN JAPAN (60 pages) formation published from 1983 onward. Objective By G. Matsuyama, 1990. was to obtain a clear picture, particularly of the relative merits of zinc-nickel and zinc-iron electro- Tables and drawings accompany the many photo plated steels. graphs which illustrate this review. Listed are the 12 conclusions reached afterstudying 130 papers, patents and technical articles. 13 005 APPLICATION OF INCO-COLORED STAINLESS 14 003 NICKEL AIDS CHIPS' NEED FOR SUPER CLEAN STEEL IN JAPAN (38 pages) WATER (1 page) By H. Sato, 1992. By Arthur H. Tuthill, reprinted from Nickel, Vol. 4 In 1972 Inco Limited announced development of a (2), 1988. new coloring process easily adaptable to commercial- Demands by the semiconductor industry gave new scale production. meaning to the term clean water. If water contained This review discusses the process and in particular Ippm total dissolved solids, that was too dirty for the Japanese bathtub market, properties of colored washing infinitesimal chips. Needed: zero total dis- film, coloring technology, pretreatment, color con- solved solids. trol, muiticoloring, continuous coloring and harden- Ion exchange, developed to supply nuclear-grade ing as well as applications that include roofing and water, and reverse osmosis technology, used for puri- siding, interior and exterior, ornamental work, table- fying drinking water, were linked to become a de- ware and signage. ionization reclamation system. It provides water clean Tables document the results of various corrosion, enough to meet what are believed to be the most heat-resistance, scratch and abrasion tests. stringent standards for water purity. 25

14 004 NICKEL STEELS IN ARCTIC SERVICE (7pages) 14 009 ELECTROLESS Ni COATINGS WIN ON By C.M. Schillmoller and Bruce D. Craig, reprinted UNIFORMITY (1 page) from Corrosion '87. 1987. By Atkin Simonian, reprintedfrom Nickel, Vol. 5 (3), The beneficial effects of nickel on fracture toughness at 1990. low temperatures, mechanical properties of thick section Primary technical reasons for selecting electroless forging and enhanced weldability of steels are discussed. nickel coatings include corrosion resistance, wear Materials examined include nickel steels for structural resistance (hardness and lubricity), bondability and applications - offshore structures and storage facilities solderability, metallization on nonconductive sub- -and those specific to oil and gas production. strates, and magnetic properties. Also addressed: the use of highly-alloyed nickel- One feature that gives electroless nickel coatings an containing materials for enhanced corrosion resist- added boost over alternative inorganic coatings is the ance. uniformity of thickness. Reproduced by courtesy of the [United States] 14 005 MODERN ELECTROFORMING (6 pages) Metal Finishing Suppliers' Association is a quick- By Dr. S.A. Watson, reprinted from Transactions of reference table listing electroless nickel applications the Institute of Metal Finishing, 1989. and reasons for their use. Reviews several aspects of current electroforming 14 010 SAVE $US50 000 USING STAINLESS PIPE technology. INSTEAD OF DUCTILE IRON (1 page) Concentrated on are: Nickel alloys and eloctroformed tooling, control of stress in nickel By Arthur H. Tuthill, reprinted from Nickel, Vol.5 (4), electrodeposits, mirrors; Electroforms used in the 1990. printing industry, aerospace applications, To handle the raw water and pipe gallery needs for a electroformed foils and copier belts; Perforated new municipal water treatment plant, Unified Number- products made by means of photoresists, optical ing System S 30403 stainless steel pipe was specified readout discs and holograms. instead of ductile iron. The saving was $US50 000. 14 006 SEDIMENTATION IN CONDENSERS AND HEAT 14 011 VERSATILITY OF HIGH-ALLOYED Ni-Cr-Mo EXCHANGERS: CAUSES AND EFFECTS WELDING CONSUMABLES (4 pages) By Dr. Norman Stephenson, reprinted from Welding By Arthur H. Tuthill, reprinted from Power and Metal Fabrication,Vol. 58 (7&8), 1990. Engineering, Jun 1985. In addition to their use in joining essentially matching Little attention has been given to the important effect wrought alloys, several highly-alloyed Ni-Cr-Mo weld- of low velocities on condenser and heat exchanger ing consumables have been adopted and modified for tubing performance. welding operations on other materials and for the In particular, debris play a critical role in inlet-end production and welding of composites. erosion-corrosion, and sedimentation left unremoved This article looks at the composition and properties of significantly hinders heat transfer. the consumables and their applications in the naval Low velocity is frequently lost sight of in the rush and marine, oil and gas, power, pollution control, to retube and get a unit back on stream, and so failures desalination, chemical, refinery, petrochemical, proc- tend to repeat. ess, cryogenics and surfacing industries . Welding processes and techniques suitable for these 14 007 EVALUATION OF BLEACH PLANT PIPING consumables for various applications are briefly re- MATERIALS (4 pages) viewed. Relevant welding metallurgy is examined, By Arthur H. Tuthill and A. Gamer, reprinted from and possible areas of development are discussed. Tappi Journal, Jun 1990. 14 012 ELECTROFORMING TODAY (17pages) Tests on fabricated pipes in the bleach plant show that further work is needed to establish an inside By Dr. S. Alec Watson, reprinted from proceedings, root pass procedure which avoids the formation of Surface Finishing Congress Asia Pacific Interfinish '90, unmixed zones. Possible options include automatic hosted by Australasian Institute of Metal Finishing and gas tungsten arc welding, a greater root gap, or SingaporeFinishing Society, Singapore, Nov 19-22,1990. consumable inserts. This paper reviews several aspects of current electroforming technology, particularly with regard to 14 008 SINKS OF STAINLESS CLEAN BEST, BEAT nickel and its alloys. BACTERIA (2pages) Developments in applications of electroforming dis- By Dr. John T. Holah, reprinted from Nickel, Vol.5 (4), cussed include tools, foils, aerospace applications, per- 1990. forated products, optical read-out discs and holograms. Required to resist aggressive fluids, abrasive materials and impacting utensils - and to maintain its 14 013 CORROSION OF METALLIC AND NONMETALLIC attractive appearance - that's the demanding role of PIPING FOR BLEACH PLANT D STAGE the domestic sink. FILTRATE (8 pages) One of the popular characteristics of nickel-con- By David C. Crowe and Arthur H. Tuthill, reprinted taining stainless steel that has become the accepted from Proceedings of the TAPPI Engineering material for sink construction during the past 40 Conference, Seattle, Sep 25, 1990. years is the readiness with which its surface can be The condition of six-inch diameter by two-foot long cleaned of soil and bacteria, of particular hygienic spools of PVDF- and PTFE-lined steel, welded titanium, importance in food handling. Alloy G, and AISI type 31 7L steel after approximately 10 years' exposure in a D stage filtrate line is reported. 26 Weld- and heat-affected zone performances are described. This report is part of TAPPI Metals Sub- 14 019 RESIST CHLORIDES, RETAIN STRENGTH AND committee CA4924 Bleach Plant Pipe Test Program. DUCTILITY WITH DUPLEX STAINLESS STEEL ALLOYS (8 pages) 14 014 PERFORMANCE OF HIGHLY-ALLOYED By Richard E. Avery, reprinted from Chemical MATERIALS IN CHLORINE DIOXIDE BLEACHING Engineering Progress, March 1991. (9 pages) Covering the characteristics of duplex stainless steels By Arthur H. Tuthill andDonald E. Bardsley, reprinted and the effect of welding them, the article discusses in from Proceedingsof the Technical Association of the detail nickel-enriched filler metals and welding prepa- Pulp and Paper Industry Engineering Conference, rations, processes and procedures. Seattle, Sep 25, 1990. This data-packed report draws six main conclusions 14 020 WELD FABRICATION OF A 6% MOLYBDENUM on the performance of specific nickel-base alloys for ALLOY TO AVOID CORROSION IN BLEACH D stage environments, and on developing the true PLANT SERVICE (17 pages) long-term general corrosion rate. By Edward L. Hibner, Evan B. Hinshaw and Stephen Lamb, reprinted from Proceedings, Technical 14 015 AMBIENT-TEMPERATURE STRESS-CORROSION Association of the Pulp and PaperIndustry, 1992. CRACKING OF AUSTENITIC STAINLESS STEEL IN SWIMMING POOLS (2pages) Addressed is the formation of unmixed zones that can form during the weld fabrication of N 08925, one of By Dr. John W. Oldfield and Brian Todd, reprinted the 6%-molybdenum alloys. from Materials Performance, Dec 1990. Using proper weld fabrication procedures and joint Chloride stress-corrosion cracking failures of Unified design, these mixed zones can be shown to be mini- Numbering System S 30400 and S 31600 components mized and the weld corrosion integrity of the joint in the atmosphere of indoor swimming pools are conformed using standard corrosion test procedures. discussed. No effect of heat tint or heat input on corrosion No failures under immersed conditions had been resistance was discerned and the root pass weld was reported, nor in the atmosphere associated with out- not preferentially attacked, it is stated. door pools. Changes in pool operations during the last few years 14 021 ALLOY 400 FOR USE IN HIGH PRESSURE are listed. FEEDWATER HEATERS (6pages) By Dennis W. Rahoi, reprinted from Proceedings of 14 016 FUSION BOUNDARY CRACKING IN CuNilOFe materials workshops for the power industry, Nickel WELDMENTS (7pages) Development Institute, 1993. By Dr. Norman Stephenson, reprinted from Joining Figures and tables help to illustrate why Alloy 400 Sciences, Vol I (1), 1991. (UNS N04400) is well suited for use in high pressure feedwater heaters. The main reason for its success is 14 017 STRESS-CORROSION CRACKING IN NICKEL- its high corrosion-resistance and the stress-relieved BASE ALLOY WELDMENTS (5pages) temper has excellent mechanical strength and corre- By Dr. David E. Jordan, International Institute of sponding allowable stress levels. Welding, Montreal 1990. 14 022 ELECTRODEPOSITED COATINGS OF ZINC- In the spectrum of corrosion-resisting steels and alloys NICKEL (4 pages) in which nickel is a significant constituent, nickel- By Dr. S. Alec Watson, reprinted from Transactions base alloys are often preferred because of their resist- of the Institute of Metal Finishing, Vol. 70 (1), 1992. ance to stress-corrosion cracking. Apart from chloride stress-corrosion cracking, The automotive industry is increasingly using preplated which can arise in a municipality of applications in steel coil for body shells in order to increase the sensitive materials such as austenitic stainless steels, service life of vehicles. there are media in more specialized applications Zinc-nickel and zinc-iron alloys have been devel- that require careful choice of nickel alloys and the oped to raise resistance to corrosion compared with condition in which they are used, including plain zinc of equal thickness on steel, but only zinc- hydrofluoric and polythionic acids, caustic soda, nickel is used in Europe. and molten metals. Electrodeposited zinc-nickel is also used increasingly Data on unwelded materials are included in this to replace plain zinc in order to upgrade the performance review since their performance under stress is related of components plated in conventional plating plants. to the characteristics of the welded joints. Performance of the alloy coatings is discussed. 14 018 GUIDELINES FOR WELDING DISSIMILAR 14 023 PERFORMANCE OF HIGHLY ALLOYED METALS (6 pages) MATERIALS IN CHLORINATION BLEACHING (10 pages) By Richard E. Avery, reprinted from Chemical Engineering Progress, May 1991. By Arthur H. Tuthill and Donald E . Bardsley, reprinted from National Association of Corrosion Nickel-containing stainless steels and nickel- and cop- Engineers, NACE, CORROSION '92, 1992. per-base alloys are readily fusion welded to carbon and low-alloy steel and to each other. Data from exposure tests of fifteen alloys in chlorina- Methods are described to estimate the weld metal tion bleaching stage environments is presented. The composition of dissimilar-metal welds. Knowing the data tends to support the wide applicability of the 6 composition, weld properties can be predicted for a percent molybdenum stainless steels for bleach plant wide range of dissimilar-metal welds. service. 27 14 024 A REVIEW OF RECENT TRENDS IN NICKEL 14 029 FABRICATION OPTIONS FOR NICKEL- ELECTROPLATING TECHNOLOGY IN NORTH CONTAINING ALLOYS IN FGD SERVICE: AMERICA AND EUROPE (8 pages) GUIDELINES FOR USERS By Dr. G. A. DiBari and Dr. S. Alec Watson. Presented By Richard E. Avery, reprinted from Materials at the Nickel Development Institute Plating Workshops, Performance, Dec 1993 Japan, Nov 1992. Nickel-containing flue gas desulphurization (FGD) Nickel electroplating is one of the most versatile systems are fabricated by using sheet linings and surface finishing processes available having a broad rolled- and explosion-clad plates of solid alloys. Se- spectrum of end-uses that encompass decorative, lection of the particular method is based primarily on engineering and electroforming applications. Al- the total project cost and customerpreferencebasedon though the main focus of this talk is on those previous experience. The important fabrication and applications, discussion of economic, regulatory quality control steps are discussed. and quality assurance trends is included to provide an overview of the current status of nickel electro- 14 030 WATER TANK BUILT TO LAST 60 YEARS plating. (2 pages) 14 025 STAINLESS STEEL RAILCARS REDUCE By K. Kuwayama, reprinted from Nickel, Vol.10 (1), WEIGHT, SAVE ENERGY (1 page) 1994. Reprintedfrom Nickel, Vol 8 (2), 1992. Excerpt from The city ofMatsuyama on theJapanese island of Shiboku NiDI Review Series 13 006. has built the country's first stainless steel municipal water tank in order to ensure its residents a safe, steady Shown are the carbody's main parts of high-strength supply of drinking water well into the 21 st Century. This stainless steel. article tells why they chose stainless steel. 14 026 CORROSION BEHAVIOUR OF STAINLESS 14 031 NICKEL ALLOY PLATING STEEL, NICKEL BASE ALLOY AND TITANIUM WELDMENTS INCHLORINATION AND By S. A. Watson, reprinted from ASM Handbook, CHLORINE DIOXIDE BLEACHING (20pages) Volume 5, Surface Engineering, 1994. By Arthur H. Tuthill, Richard E. Avery and Andrew Information available on the industrial plating of Garner. Reprinted from Proceedings of the Technical nickel alloys refers to nickel-iron, nickel-cobalt, Association of the Pulp and Paper Industry, TAPPI, nickel-manganese and zinc-nickel deposition. This 7th InternationalSymposium on Corrosionin the Pulp article will highlight nickel-iron, nickel-cobalt and and Paper Industry, Orlando, FL, 1992. nickel-manganese which are of practical interest, plus a few paragraphs on nickel-chromium binary An overview of a decade long series of programs and ternary alloys. which exposed welded coupon and full diameter pipe in chlorination and chlorine dioxide bleaching 14 032 RECYCLING A RAILCAR CLASSIC equipment. Findings have guided procedures for (3 pages) the fabrication and post fabrication cleanup of over By James Borland, reprinted from Nickel, Vol. 10 (4), 75 6%-Mo stainless steel washers. Findings are also 1995. applicable to 6% Mo, nickel base alloy, clad nickel base alloy, titanium and plastic-lined piping for There may be no better testimonial to the quality and bleach plants. Guidelines for procurement and fab- longevity of stainless steel railcars than this award- rication of piping materials are included. Applica- winning modernization program of Canada's trans- bility to mixer-to-tower, tower-to-vat and filtrate continental passenger fleet. piping sections are reported. Via Rail, Canada's publicly owned passenger rail company, decided to refurbish its 40-year-old trans- 14 027 MANAGING GALVANIC CORROSION continental fleet of stainless steel railcars and got more By Arthur H. Tuthill, reprinted from the 12th than it bargained for - more efficiency, more cost International Corrosion Congress, NACE International, savings and more customer satisfaction. 1993. 14 033 SYSTEMIC NICKEL: THE CONTRIBUTION MADE This paper summarized 22 case histories of severe gal- BY STAINLESS STEEL COOKING UTENSILS vanic corrosion problems and solutions that the author (7pages) has encountered in heat exchangers, condensers, pumps By G.N. Flint and S. Packirisamy, reprinted from and valves, welds in hull plate, copper nickel and nickel Contact Dermatitis, Vol. 32 (4), 1995. copper, fasteners, ballast tanks, and partially lined tanks. Guidelines are developed to assist engineers in managing An extensive programme of cooking operations, galvanic corrosion problems they may encounter. using household recipes, has shown that, apart from aberrant value associated with new pans on 14 028 LAMBTON'S ALLOY LINING (3 pages) first use, the contribution made by 19 Cr/9 Ni By James Borland, reprinted from Nickel, Vol. 9 (4), stainless steel cooking utensils to nickel in the diet 1994. is negligible. The amount of nickel (0 to 8 g) When Canada's largest electric utility began rehabili- derived from the utensils in standard portions of tating its Lambton coal-fired generating plant at various "aggressive" foodstuffs tested was less Courtright, Ont., it decided to install flue-gas scrub- than that to be found occurring in I square of a bers to comply with environmental regulations and to bitter-sweet chocolate bar. line them with rubber to prevent corrosion. It was later re-evaluated and wallpapered with N10276. 28

14 034 STAINLESS STEEL REINFORCING AS increase low-temperature toughness. Finally, im- CORROSION PROTECTION (7pages) proved test methods and equipment for measuring By D.B. McDonald, M.R. Sherman, D.W. Pfeifer, and toughness can improve yields by alleviating unnec- Y.P. Virmani, reprinted from Concrete International, essary rejects. May, 1995. 14 039 PURITY OF FOOD COOKED IN STAINLESS Designers are focusing more attention on the con- STEEL UTENSILS (1 pages) struction of corrosion-resistant reinforced concrete By G.N. Flint and S. Packirisamy, reprinted from structures. One potential method is to use highly Food Additives & Contaminants, Vol. 14 (2), 1997. corrosion-resistantreinforcement. Solid stainless steel and stainless steel clad reinforcing bars have been An extensive program of cooking operations, using used in Europe for many years. This paper discusses household recipes, has shown that, apart from aberrant research findings from corrosion studies of these ma- values associated with new pans on first use, the terials, and some recent results from laboratory and contribution made by 19%Cr/9%Ni stainless steel field investigations have been reviewed. Costs associ- cooking utensils to chromium and nickel in the diet is ated with the use of such bars are also discussed. negligible. A higher rate of chromium and nickel release in new pans on first use was observed on 14 035 THE INFLUENCE OF RISK ANALYSIS ON THE products from four manufacturers and appears to be ECONOMICS OF CARBON STEEL AND CRA related to surface finish, since treatment of the surface CLAD FLOWLINES (8 pages) of a new pan was partly, and in the case of By B.D. Craig and R.S. Thompson. Presented at the electropolishing, wholly effective in eliminating their 1995 Offshore Technology Conference, Paper OTC initial high release. 7788, Houston, TX, May 1-4, 1995. 14040 FABRICATION TECHNIQUES FOR SUCCESSFUL Recently a method was presented to assist in making the ORBITAL TUBE WELDING (8 pages) decision to install corrosion resistant alloy (CRA) pipe- By Barbara K. Henon, reprinted from Tube and Pipe lines or inhibited carbon steel. This method incorpo- Quarterly, Vol. 7 (1&2), 1997. rated risk into the decision process. Previous economic analyses comparing solid and clad CRA pipelines to The past decade has seen a revolution in piping system those constructed from inhibited carbon steel have only fabrication technology for many industries. The tech- taken into account the costs for each option without nology has been driven by the semiconductor indus- considering the probability orcost of failure. This paper try's need to deliver process gases to the point-of-use extends the earlier work by examining the effects of at purity levels unheard of 10 years ago. varying the assumed probability of failure of the clad This level of technical sophistication requires a piping pipeline and introducing utility effects. system with an extremely smooth interior surface finish to prevent adherence of particulates, moisture, 14 036 WELDING DUPLEX AND SUPER-DUPLEX or other impurities to the tubing walls. STAINLESS STEELS (23 pages) The increasing demand for high-quality joining of By L. van Nassau, H. Meelker and J. Hilkes, reprinted piping systems in these critical industries in the early from Welding in the World, Vol. 31, (5), 1993. 1980s resulted in an increased use of portable orbital welding systems that operate on single-phase electri- Industrial conditions, especially involving Cl-containing aqueous fluids, may require materials with im- cal power. proved corrosion and/or strength properties compared 14041 LONG LIFE AMBITION (1 page) to a standard austenitic stainless steel grade (AISI 316L By James Borland, reprinted from Nickel, Vol. 12 (1), or X2 CrNiMo 1812). To meet this need a duplex 1996. stainless steel grade with approximately 18.5% Cr, 5% Guildhall, the building that has been the centre of Ni, 2.7% Mo and 0.1% N was introduced in the 1970s. government for London since the 13th century, is This grade is no longer promoted by the manufacturers gaining a 50-million pound sterling addition that uses but new low carbon stainless steel grades with 22-27% stainless steel reinforcing to ensure its long life. Cr, 4-8% Ni, 0.1-0.3% N, with orwithout Mo (1.5-4%), and in some cases with additional elements, have been 14 042 INTERNATIONAL HARMONIZATION RELATED developed. They form the current families of duplex TO PERSISTENCE AND BIOAVAILABILITY and super-duplex stainless steels, with the austenite- (12 pages) ferrite structure in common. By Peter M. Chapman et al., reprinted from Humian Early applications, and even today's projects, have andEcologicalRiskAssessinent,Vol.2 (3), September, frequently been associated with such problems as crack- 1996. ing or preferential corrosion behaviour. Consequently, welding of duplex and super-duplex stainless steel has The 1992 United Nations Conference on Environment been subject to fundamental and applied research. and Development (UNED) identified harmonization of classification and labelling of chemicals by the year 14037 WELDING STAINLESS AND 9% NICKEL STEEL 2000 as one of six program areas requiring interna- CRYOGENIC VESSELS (6pages) tional cooperation. By Richard E. Avery and David Parsons, reprinted Three key measures are presently proposed for clas- from Welding Journal, November, 1995. sifying any substance as "dangerous to the environment"; persistence, bioaccumulation, and toxicity. It is well known that ferritic steels, including the low- The potential for misleading classification and la- alloy steels, lose toughness and ductility at low belling of materials is described. It is suggested that temperatures. The ductile-brittle transition tempera- environmental objectives will not be achieved if ture, i.e., a temperature below which a metal be- inappropriate testing criteria are used. comes brittle, is affected by steel-making practices. Alloys with increasing nickel content substantially 29 14 043 STEELED AGAINST THE ELEMENTS - containing stainless steel, the behaviour of simple STAINLESS STEEL DOORS CAN STAND UP TO structures subjected to drop weight test, generating FIRE AND CORROSIVE ENVIRONMENTS strain rates in the range l0s-'

Diskettes available from NiDI

D-0001 STAINLESS STEEL INFORMATION AND DESIGN DATA - NORTH AMERICAN EDITION The diskette is easy to use and many subjects of stainless steel technology are detailed under sections 3.5" Computer diskette, for use on IBM - compatible headed "Economic Considerations", "Physical and Me- systems. Version 2.1, The Nickel Development chanical Properties" and "Corrosion Resistance and Fab- Institute. rication". Search facilities separate only those steels with This diskette provides specifications, properties, codes strengths above a chosen minimum or with chosen andotherinformationfor44alloys includingAmerican percentages of alloying elements. "Family trees" provide Iron and Steel Institute (AISI) Types 200,300 and 400 rapid access to stainless steels with particular properties. series and cast, precipitation hardening and duplex The disk is not copy-protected; users are encour- stainless steels. aged to make and distribute copies. In addition, Version 2.1 provides a graphical presentation of relative production volumes by alloy, D-0003 CREVICE CORROSION ENGINEERING GUIDE economic considerations, corrosion resistance, and 3.5" Computer diskette, for use on IBM - compatible high-temperature properties. systems. Produced by The Nickel Development A new interactive weight calculator is also included Institute in conjunction with Cortest Laboratories Ltd. and American Society for Mechanical Engineers (UK), and LaQue Center for Corrosion Technology (ASME) code specifications have been added. (US), 1994. The disk is not copy-protected; users are encour- Corrosion engineers and others involved in materials aged to make and distribute copies. specification can now use a simple computer program to determine which grade of stainless steel is best able to D-0002 GUIDE TO STAINLESS STEELS - avoid crevice corrosion in a given aqueous environment. INTERNATIONAL EDITION The program allows the user to select and manipu- 3.5" Computer diskette, for use on any IBM - late input data according to the environment of inter- compatible systems using DOS 3.0 or higher and est. Once variables such as water chemistry, equipped with 512K of memory. temperature, scaling tendency, and pH level have been It provides compositions, metallurgy, applications, selected, the program indicates the likely corrosion physical and mechanical properties at ambient, low performance of a range of stainless steel types. Output and high temperatures, and welding consumables data is clear and easily interpreted. for about 100 austenitic, super-austenitic, duplex, The guide is based on a mathematical model of the ferritic, martensitic and precipitation hardening corrosion process and has been validated by an exten- wrought UNS (AISI) and Euronorm stainless steels. sive range of exposure data. It covers a wide variety of Composition and product-form specifications in- service conditions including those in such industries clude similar ISO, British, German and Japanese as power, pulp and paper, desalination, marine, and grades. water treatment.

Videos available from NiDI

V-0001 STAINLESS STEEL: THE EFFECTIVE SOLUTION V-0002 FRESH APPROACHES TO MOLD STEEL Video cassette, 15 minutes, 1992. SELECTION Complemented by NiDI Technical Series 10,042, this Video cassette, 10 minutes, 1993. video is a visual demonstration of the cost-effective- This video is primarily intended for apprentices and ness of stainless steel as a materials both offshore and students of mold making and mold design. It intro- onshore, especially in the oil industry. The video duces, enlivens and expands the subject matter pre- gives graphic illustration of tests commissioned by sented in NiDI's Technical Series publication 10,062 NiDI, which domonstrate the additional safety margin which bears the same title. provided by stainless steel in the event of fire. This video was commissioned by NiDI in the wake of the Piper Alpha oil rig disaster.

Periodicals available from NiDI

NICKEL COMMUNIQUE Aickel, published quarterly by NiDI, highlights new and interest- Communique is a review of environmental legislation and ing uses of nickel and nickel-containing materials -- from the concerns that may affect the use of nickel or nickel-containing engineering marvels of the modem world to everyday eyeglass materials, including occupational health and safety matters. frames. Nickel is circulated, free of charge, to 37,000 readers in Please contact any of the NiDI offices to be included on the more than ninety countries and a summary of each issue's contents circulation of Communique. is translated into French, German, Spanish and Japanese. If you would like to be included on our circulation list, contact any of the NiDI offices listed on the back of this catalogue. 32 INDEX

Summaries of publicationslisted are on the pages indicated.

page 10 010 Architecture - a demanding market for AEROSPACE stainless steel ...... 11 337 Alloy 713C technical data ...... I 10 037 Stainless steel in architecture ...... 14 393 High-temperature, high-strength nickel-base alloys ...... 2 10 068 Specifying stainless steel surface treatments ...... 18 497 IN-738 alloy - preliminary data ...... 3 11 007 Guidelines for the welded fabrication of 10 084 Electroforming - a unique metal fabrication process ..... 20 nickel-containing stainless steels for corrosion 14 037 Welding stainless and 9% nickel steel resistant services ...... 21 cryogenic vessels ...... 28 11 013 Stainless steel in architecture, building and 14 040 Fabrication techniques for successful construction - guidelines for roofs, floors orbital tube welding ...... 28 and handrails...... 21 11 014 Stainless steel in architecture, building and AGRICULTURE construction - guidelines for maintenance 415 Corrosion resistance of nickel-containing and cleaning ...... 21 alloys in phosphoric acid ...... 2 11 015 Stainless steel in architecture, building and 959 Standard forms and finishes for stainless steels ...... 3 construction - guidelines for building exteriors ...... 21 9025 Stainless steel for bulk materials handling ...... 8 11 016 Directory of North American suppliers of stainless steel products for building and construction ...... 22 10 080 Cleaning stainless steel surfaces prior to sanitary service ...... 19 11 019 Stainless steel plumbing ...... 22 11 017 Ni-Hard material data and applications ...... 22 12 004 Answers for architects who design for beauty, performance, utility and prestige with nickel 14 033 Systemic nickel: the contribution made by stainless steel ...... 22 cooking utensils ...... 27 stainless steel 12 006 Technical manual for the design and construction ALLOY STEELS of roofs of stainless steel sheet ...... 23 278 31/2% nickel steel for low-temperature service ...... I 12 008 Piping manual for stainless steel pipes for buildings ...... 23 12 009 Advantages for architects who design for beauty, 388 Annealed, hot rolled, and normalized permanence, utility and prestige with nickel nickel alloy steels ...... 2 containing stainless steel; an architect's guide 389 Isothermal transformation diagrams of on corrosion resistance ...... 23 nickel alloy steels ...... 2 12 010 Stainless steel in swimming pool buildings .23 392 Hardenability of nickel alloy steels ...... 2 12 011 Design manual for structural stainless steel .23 406 Nickel alloy steel castings ...... 2 13 003 Development of resin-coated stainless steel in Japan . 24 439 Nickel alloy steels for heavy forgings ...... 2 13 005 Application of Inco-colored stainless steel in Japan . 24 447 Alloy steel compositions ...... 2 14 034 Stainless steel reinforcing as corrosion protection . 28 472 Nickel alloy tool steels ...... 3 14 036 Welding duplex and super-duplex stainless steels . 28 479 Nickel alloy nitriding steels ...... 3 14 041 Long life ambition ...... 28 1108 Nickel alloy steel plates ...... 3 14 043 Steeled against the elements - stainless steel doors 1203 Six reasons for specifying nickel carburizing steels ...... 3 can stand up to fire and corrosive environments ...... 29 1205 The role of nickel in carburizing steels ...... 4 14 044 Stainless steel piping ...... 29 1208 Welding 9% nickel steel - a review of the current practices...... 4 AUTOMOTIVE 1232 Fracture toughness and related characteristics 1203 Six reasons for specifying nickel carburizing steels ...... 3 of the cryogenic nickel steels ...... 4 1205 The role of nickel in carburizing steels ...... 4 1238 Low-temperature properties of nickel alloy steels ...... 4 4353 Copper-nickel alloys - engineering properties 1278 IN-787, a precipitation hardening alloy steel, and applications ...... 6 properties and applications...... 5...... 4421 The welding of flake and spheroidal graphite 4393 Cast nickel alloy steels engineering properties ...... 6 Ni-Resist castings ...... 6 4419 18% nickel maraging steel-engineering properties ...... 6 9022 Automotive stainless steels ...... 8 10 028 Softening high-hardenability steels for 10 028 Softening high-hardenability steels for machining and cold forming ...... 13 machining and cold forming ...... 13 10 030 Nine per cent nickel - 28 years of reliable 10 078 Electroplating on plastics ...... 19 service in liquefied natural gas containment ...... 13 11 005 Modem carburized nickel alloy steel ...... 20 10 062 Fresh approaches to mold steel selection .17 11 006 Nickel in powder metallurgy steels ...... 21 10 070 Understanding and preventing cracks in mold steel . 18 11 018 Properties and applications of Ni-Resist and 11 005 Modem carburized nickel alloy steel .20 ductile Ni-Resist alloys ...... 22 14 004 Nickel steels in arctic service .25 11 019 Stainless steel plumbing ...... 22 14 037 Welding stainless and 9% nickel steel 13 001 Zinc-nickel alloy electroplated steel coil and other cryogenic vessels .28 precoated coil for use by the automotive industry: SR-0005 Occupational exposure limits for nickel and a review of literature published 1983 to 1987 ...... 24 nickel compounds .30 14 002 Why zinc-nickel coated steels? ...... 24 V-0002 Fresh approaches to mold steel selection ...... 31 14 022 Electrodeposited coatings of zinc-nickel ...... 26

ARCHITECTURE CAST IRONS AND CAST ALLOYS 9010 Stainless steels for building exteriors ...... 7 70 Ni-Hard - engineering properties and applications ...... I 9012 Finishes for stainless steels...... 7 242 Machining and grinding Ni-Resist and ductile 9014 Design guidelines for the selection and use Ni-Resist ...... I of stainless steels ...... 8 310 Nickel and grey iron - influence on structure 9031 Stainless steel - suggested practices for roofing and properties ...... 1 flashing, copings, fascias, gravel stops, drainage ...... 9 352 The role of alloys in engineering grey iron castings ...... 2 9034 Stainless steel membrane roof ...... 9 406 Nickel alloy steel castings ...... 2 10 004 Fabrication and post-fabrication cleanup of 1196 Cast heat-resistant alloys ...... 3 stainless steels...... 10 1267 Abrasion-resistant castings for handling coal ...... 5 4077 Nickel SG iron - engineering properties ...... 6 33

4383 IN-519 cast chromium-nickel-niobium 10 026 Fabrication and metallurgical experience in heat- resisting steel - engineering properties ...... 6 stainless steel process vessels exposed to 4393 Cast nickel alloy steels engineering properties ...... 6 corrosive aqueous environments ...... 13 4421 The welding of flake and spheroidal graphite 10 032 Practical guide to using 6Mo austenitic stainless steel ..... 13 Ni-Resist castings ...... 6 10 039 Stainless steel sheet lining of steel tanks and 10 018 Influence of carbide content on the stress corrosion pressure vessels ...... 14 cracking of Ni-Resist cast irons in warm seawater ...... 11 10 040 The right metal for heat exchanger tubes ...... 14 10 021 Procurement of quality stainless steel castings ...... 12 10 042 Stainless steel for durability, fire-resistance 10 038 Development of abrasion-resistant, nickel and safety ...... 15 containing alloy white irons of high hardness...... 14 10 043 Design, water factors affect service-water 10 071 Wrought and cast heat resistant stainless steels piping materials ...... 15 and nickel alloys for the refining and 10 044 Practical guide to using duplex stainless steels ...... 15 petrochemical industries ...... 18 10 056 Practical guide to high-temperature alloys ...... 16 11 004 Materials for saline water, desalination and 10 057 Selection and performance of stainless steels oilfield brine pumps...... 20 and other nickel-bearing alloys in sulphuric acid ...... 17 11 017 Ni-Hard material data and applications ...... 22 10 062 Fresh approaches to mold steel selection ...... 17 11 018 Properties and applications of Ni-Resist and 10 063 Selection and use of stainless steels and ductile Ni-Resist alloys ...... 22 nickel-bearing alloys in organic acids ...... 17 CHEMICAL AND PROCESS 10 064 Clad engineering ...... 17 10 066 Preventing stress-corrosion cracking of 279 Resistance of nickel and high-nickel alloys to austenitic stainless steels in chemical plants ...... 18 corrosion by hydrochloric acid, hydrogen chloride and chlorine ...... I 10 068 Specifying stainless steel surface treatments ...... 18 281 Corrosion resistance of nickel and nickel 10 070 Understanding and preventing cracks in mold steel ...... 18 containing alloys in caustic soda and other alkalies ...... I 10 074 The corrosion resistance of nickel-containing alloys 415 Corrosion resistance of nickel-containing alloys in hydrofluoric acid, hydrogen fluoride, and fluorine ...... 18 in phosphoric acid ...... 2 10 075 Selection and performance of stainless steels 443 Corrosion resistance of nickel-containing alloys in and other nickel-bearing alloys in nitric acid ...... 19 hydrofluoric acid, hydrogen fluoride and fluorine ...... 2 10 077 Stainless steels for bioprocessing ...... 19 515 Some nickel copper casting alloys - engineering 10 079 Effectiveness of sanitation with quaternary properties ...... 3 ammonium compound or chlorine on stainless steel 1258 Corrosion fatigue properties of and other domestic food-preparation surfaces ...... 19 nickel-containing materials in seawater ...... 4 10 080 Cleaning stainless steel surfaces prior to 1259 The successful use of austenitic stainless steels sanitary service ...... 19 in seawater...... 4 10 083 Corrosion performance of Ni-Cr-Fe alloys 1262 Resistance of stainless steel to corrosion in in geothermal hypersaline brines ...... 20 naturally occurring waters ...... 4 10 084 Electroforming - a unique metal fabrication process ..... 20 1285 Corrosion resistance of nickel-containing alloys 10 085 Microbiologically influenced corrosion of in organic acids and related compounds ...... 5 stainless steels by water used for cooling and 1318 The corrosion resistance of nickel-containing alloys hydrostatic testing...... 20 in sulphuric acid and related compounds ...... 5 11 007 Guidelines for the welded fabrication of 2828 Corrosion resistance of the austenitic chromium nickel-containing stainless steels for nickel stainless steels in chemical environments ...... 6 corrosion-resistant services ...... 21 4353 Copper-nickel alloys - engineering properties 11 017 Ni-Hard material data and applications ...... 22 and applications ...... 6 11 018 Properties and applications of Ni-Resist and 4421 The welding of flake and spheroidal graphite ductile Ni-Resist alloys ...... 22 Ni-Resist castings ...... 6 11 019 Stainless steel plumbing ...... 22 9005 Role of stainless steels in industrial heat exchangers ...... 7 10 083 Corrosion performance of ni-cr-fe alloys 9008 Stainless steels for pumps, valves, and fittings ...... 7 in geothermal hypersaline brines ...... 20 9009 Stainless steels for pulp and paper manufacturing ...... 7 12 002 Performance of tubular alloy heat exchangers in seawater service in the chemical process industries ..... 22 9013 Stainless steels in ammonia production ...... 8 12 007 Copper-nickel alloys - properties and applications ...... 23 9021 Role of stainless steel in petroleum refining ...... 8...... 14 003 Nickel aids chips' need for super clean water ...... 24 9024 Design guidelines for stainless steel in piping systems ...... 8 14 006 Sedimentation in condensers and heat exchangers: 9026 Stainless steels for evaporators-concentrators ...... 8 Causes and effects ...... 25 9030 A discussion of stainless steels for surface 14 007 Evaluation of bleach plant piping materials ...... 25 condensers and feedwater heater tubing ...... 9...... 9 14 010 Save $US50 000 using stainless pipe instead 9032 Stainless steel: Effective corrosion control in of ductile iron ...... 25 water and waste-water treatment plants ...... 9 14 013 Corrosion of metallic and nonmetallic piping 10 002 Evaluating installed cost of corrosion- resistant for bleach plant D stage filtrate ...... 25 piping...... 10 14 014 Performance of highly-alloyed materials in 10 004 Fabrication and post-fabrication cleanup of chlorine dioxide bleaching ...... 26 stainless steels...... 10 14 017 Stress-corrosion cracking in nickel-base 10 005 Nickel in the process industries - an anxiety alloy weldments ...... 26 closet of materials selection monsters ...... 10 14 020 Weld fabrication of a 6% molybdenum alloy 10 006 High-performance austenitic stainless steels to avoid corrosion in bleach plant service ...... 26 in the pulp and paper industry ...... 10 14 023 Performance of highly alloyed materials in 10 007 Nickel's contribution in air pollution abatement ...... 10 chlorination bleaching ...... 26 10 015 Alloy selection in wet process phosphoric acid plants ..... 11 14 026 Corrosion behaviour of stainless steel, nickel base 10 016 Test techniques for pitting and crevice corrosion alloy and titanium weldments in chlorination and resistance of stainless steels and nickel-base alloys chlorine dioxide bleaching ...... 27 in chloride-containing environments ...... 11...... 1 14 036 Welding duplex and super-duplex stainless steels ...... 28 10 019 Alloy selection for caustic soda service ...... 12 14 037 Welding stainless and 9% nickel steel 10 020 Alloys to resist chlorine, hydrogen chloride and cryogenic vessels ...... 28 hydrochloric acid ...... 12 14 040 Fabrication techniques for successful orbital tube welding...... 28 34

14 042 International harmonization related to 10 069 Effect of wiping and spray wash temperature on persistence and bioavailability ...... 28 bacterial retention of abraded domestic sink surface ...... 18 14 043 Steeled against the elements -stainless steel doors 10 077 Stainless steels for bioprocessing ...... 19 can stand up to fire and corrosive environments ...... 29 10 078 Electroplating on plastics ...... 19 14 044 Stainless steel piping ...... 29 10 079 Effectiveness of sanitation with quaternary 14 045 The role of chlorine in high temperature corrosion ammonium compound or chlorine on stainless steel in waste-to-energy plants...... 29 and other domestic food-preparation surfaces ...... 19 15 001 Nuclear service water piping, 10 080 Cleaning stainless steel surfaces prior to the Salem Nuclear Generating Station ...... 29 sanitary service...... 19 15 002 Nuclear service water piping, 10 082 Is "nickel" safe? A toxicology primer ...... 19 Oskarshamn Nuclear Power Plant ...... 29 10 084 Electroforming - a unique metal fabrication process ..... 20 V-0001 Stainless steel: the effective solution ...... 31 10 085 Microbiologically influenced corrosion of V-0002 Fresh approaches to mold steel selection ...... 31 stainless steels by water used for cooling and hydrostatic testing ...... 20 CIVIL ENGINEERING 11 013 Stainless steel in architecture, building and 10 008 H20: Nickel's contribution to distilled water, construction -guidelines for roofs, floors dams and condensers ...... 10 and handrails ...... 21 10 085 Microbiologically influenced corrosion of 11 014 Stainless steel in architecture, building and stainless steels by water used for cooling and construction - guidelines for maintenance hydrostatic testing...... 20 and cleaning...... 21 11 010 Nickel-containing materials for water control 11 015 Stainless steel in architecture, building and applications...... 21 construction - guidelines for building exteriors ...... 21 12 005 A report on the performance of stainless steel pipe If 016 Directory of North American suppliers of for water supply in underground soil environments ...... 23 stainless steel products for building and construction ...... 22 12 008 Piping manual for stainless steel pipes for buildings ...... 23 11 017 Ni-Hard material data and applications ...... 22 14 015 Ambient-temperature stress-corrosion cracking of 11 019 Stainless steel plumbing ...... 22 austenitic stainless steel in swimming pools ...... 26 12 010 Stainless steel in swimming pool buildings ...... 22 14 030 Water tank built to last 60 years .27 13 004 Stainless steel demand for kitchen equipment 14 032 Recycling a railcar classic .27 in Japan ...... 24 14 034 Stainless steel reinforcing as corrosion protection . 28 13 005 Application of Inco-colored stainless steel in Japan ...... 24 14 036 Welding duplex and super-duplex stainless steels . 28 14 008 Sinks of stainless clean best, beat bacteria ...... 25 14 041 Long life ambition .28 14 032 Recycling a railcar classic ...... 27 14 043 Steeled against the elements - stainless steel doors 14 033 Systemic nickel: the contribution made by can stand up to fire and corrosive environments . 29 stainless steel cooking utensils ...... 27 14 044 Stainless steel piping ...... 29 14 034 Stainless steel reinforcing as corrosion protection ...... 28 14 045 The role of chlorine in high temperature corrosion 14 036 Welding duplex and super-duplex stainless steels ...... 28 in waste-to-energy plants...... 29 14 037 Welding stainless and 9% nickel steel 14 046 Impact performance of model spot-welded cryogenic vessels ...... 28 stainless steel structures...... 29 14 039 Purity of food cooked in stainless steel utensils ...... 28 15 001 Nuclear service water piping, 14 040 Fabrication techniques for successful the Salem Nuclear Generating Station ...... 29 orbital tube welding ...... 28 15 002 Nuclear service water piping, 14 041 Long life ambition ...... 28 Oskarshamn Nuclear Power Plant ...... 29 14 042 Intemational harmonization related to CONSTRUCTION EQUIPMENT AND MACHINERY persistence and bioavailability ...... 28 14 043 Steeled against the elements -stainless steel doors 70 Ni-Hard - engineering properties and applications ...... I can stand up to fire and corrosive environments ...... 29 472 Nickel alloy tool steels ...... 3...... 3 14 044 Stainless steel piping ...... 29 1203 Six reasons for specifying nickel carburizing steels ...... 3 14 045 The role of chlorine in high temperature corrosion 1205 The role of nickel carburizing steels ...... 4 in waste-to-energy plants...... 29 1267 Abrasion-resistant castings for handling coal ...... 5 14 047 A metallurgical approach to metal contact dermatitis ...... 29 1278 IN-787, a precipitation hardening alloy steel, SR-0001 Nickel and nickel alloy articles that come into - properties and applications ...... 5 contact with the skin ...... 30 4421 The welding of flake and spheroidal graphite SR-0003 Nickel pickup by food cooked in stainless Ni-Resist castings ...... 6 steel utensils ...... 30 10 028 Softening high hardenability steels for SR-0006 Coinage and nickel ...... 30 machining and cold forming ...... 13 11 005 Modem carburizing nickel alloy steel ...... 20 COPPER ALLOYS 11 017 Ni-Hard material data and applications ...... 22 375 Copper-nickel alloys for feedwater heater service ...... 2 It 018 Properties and applications of Ni-Resist and 1107 The design and installation of 90/10 ductile Ni-Resist alloys ...... 22 copper-nickel seawater piping systems ...... 3 1240 The interrelation of corrosion and fouling of CONSUMER PRODUCTS metals in seawater ...... 4 1262 Resistance of stainless steel to corrosion in 1258 Corrosion fatigue properties of nickel-containing naturally occurring waters ...... 4 materials in seawater ...... 4 9026 Stainless steels for evaporators-concentrators ...... 8 1265 CA-706 copper-nickel alloy hulls: the Copper 10 004 Fabrication and post-fabrication cleanup of Mariner's experience and economics ...... 5 stainless steels ...... 10 1280 Guide to the welding of copper-nickel alloys ...... 5 10 008 H20: Nickel's contribution to distilled water, 1285 Corrosion resistance of nickel-containing alloys dams and condensers ...... 10 in organic acids and related compounds ...... 5 10 009 Burgers, fries, Coke and stainless steel ...... 10 1304 The influence of corrosion and fouling on 10 046 Cleanability in relation to bacterial retention steam condenser performance ...... 5 on unused and abraded domestic sink materials ...... 15 1305 The resistance of copper-nickel alloys to 10 065 Application of impressed current cathodic ammonia corrosion in simulated steam protection to stainless steel hot-water storage tanks ...... 18 condenser environments ...... 5 10 068 Specifying stainless steel surface treatments .18 35

4319 Copper-nickel and other alloys for desalination 9029 Role of stainless steels in desalination ...... 9 plants ...... 6 9030 A discussion of stainless steels for surface 4353 Copper-nickel alloys - engineering properties condensers and feedwater heater tubing ...... 9 and applications ...... 6 9031 Stainless steel - suggested practices for roofing, 10 011 Nickel-containing materials in marine and flashing, copings, fascias, gravel stops, drainage ...... 9 related environments ...... 11...... 9032 Stainless steel: Effective corrosion control in 10 033 Nickel-containing alloy piping for offshore water and waste-water treatment plants ...... 9 oil and gas production ...... 13 10 001 Solving high-temperature problems in oil 10 040 The right metal for heat exchanger tubes ...... 14 refineries and petrochemical plants ...... 10 11 004 Materials for saline water, desalination and 10 002 Evaluating installed cost of corrosion-resistant oilfield brine pumps...... 20 piping...... 10 12 003 Guidelines for the use of copper alloys in seawater . 22 10 004 Fabrication and post-fabrication cleanup of 12 007 Copper-nickel alloys - properties and applications . 23 stainless steels ...... 10 14 016 Fusion boundary cracking in CuNi OFe weldments . 26 10 005 Nickel in the process industries-an anxiety 14 027 Managing galvanic corrosion .27 closet of materials selection monsters ...... 10 10 006 High-performance austenitic stainless steels CORROSION in the pulp and paper industry ...... 10 266 Heat-resistant castings, corrosion-resistant 10 013 Opportunities for nickel in the oil and gas market castings, their engineering properties (1) introduction (2) deep sour gas production and applications . (3) enhanced oil recovery (4) offshore ...... 11...... 1 279 Resistance of nickel and high-nickel alloys to 10 015 Alloy selection in wet process phosphoric corrosion by hydrochloric acid, hydrogen acid plants ...... 11 chloride and chlorine . 10 016 Test techniques for pitting and crevice corrosion 281 Corrosion resistance of nickel and resistance of stainless steels and nickel-base alloys nickel- containing alloys in caustic soda and in chloride-containing environments ...... 11...... 1 other alkalies . 10 018 Influence of carbide content on the stress corrosion 318 Corrosion resistance of austenitic chromium-nickel cracking of Ni-Resist cast irons in warm seawater .... 11 stainless steels in atmospheric environments . 10 019 Alloy selection for caustic soda service ...... 12 375 Copper-nickel alloys for feedwater heater service ...... 2 10 020 Alloys to resist chlorine, hydrogen chloride and 415 Corrosion resistance of nickel-containing alloys in hydrochloric acid ...... 12 phosphoric acid ...... 2 10 021 Procurement of quality stainless steel castings ...... 12 443 Corrosion resistance of nickel-containing alloys in 10 022 The resistance of stainless steel, partly embedded hydrofluoric acid, hydrogen fluoride and fluorine ...... 2 in concrete, to corrosion by seawater ...... 12 1240 The interrelation of corrosion and fouling of 10 023 Life-cycle comparison of alternative alloys metals in seawater ...... 4 for FGD components ...... 12 1258 Corrosion fatigue properties of nickel-containing 10 024 The use of nickel stainless steels and nickel materials in seawater ...... 4 alloys in flue gas desulphurization systems 1259 The successful use of austenitic stainless steels in the United States ...... 12 in seawater ...... 4 10 025 Flue gas desulphurization; the European scene ...... 12 1262 Resistance of stainless steel to corrosion in 10 026 Fabrication and metallurgical experience in naturally occurring waters ...... 4 stainless steel process vessels exposed to 1265 CA-706 copper-nickel alloy hulls: the Copper Mariner's corrosive aqueous environments ...... 13 experience and economics ...... 5 10 027 Welding and fabrication in nickel alloys in 1278 IN-787 - a precipitation hardening alloy steel, FGD systems ...... 13 properties and applications ...... 5 10 032 Practical guide to using 6Mo austenitic stainless steel ..... 13 1279 Stress corrosion cracking behavior of wrought 10 033 Nickel-containing alloy piping for offshore oil Fe-Cr-Ni alloys in a marine atmosphere ...... 5 and gas production ...... 13 1280 Guide to the welding of copper-nickel alloys ...... 5 10 034 Applications of centrifugally-cast alloy piping 1285 Corrosion resistance of nickel-containing alloys and pipe fittings in onshore and offshore oil in organic acids and related compounds ...... S and gas production...... 14 1300 The corrosion resistance of nickel-containing 10 035 Selection of corrosion-resistant alloy tubulars alloys in flue gas desulfurization and other for offshore applications ...... 14 scrubbing processes ...... 5 10 036 A fundamental study of corrosion-resistant 1304 The influence of corrosion and fouling on zinc-nickel electroplating ...... 14 steam condenser performance ...... 5 10 039 Stainless steel sheet lining of steel tanks and 1305 The resistance of copper-nickel alloys to pressure vessels ...... 14 ammonia corrosion in simulated steam 10 040 The right metal for heat exchanger tubes ...... 14 condenser environments ...... 5 10 043 Design, water factors affect service-water 1318 The corrosion resistance of nickel-containing piping materials ...... 15 alloys in sulphuric acid and related compounds ...... 5 10 044 Practical guide to using duplex stainless steels ...... 15 2828 Corrosion resistance of the austenitic 10 045 Practical guide to using marine fasteners ...... 15 chromium- nickel stainless steels in 10 056 Practical guide to high-temperature alloys ...... 16 chemical environments ...... 6 10 057 Selection and performance of stainless steels 4319 Copper-nickel and other alloys for desalination plants ...... 6 and other nickel-bearing alloys in sulphuric acid ...... 17 4353 Copper-nickel alloys - engineering properties 10 061 Development of mechanized field girth welding and applications ...... 6 of high-alloy corrosion-resistant pipeline materials ...... 17 4421 The welding of flake and spheroidal graphite 10 063 Selection and use of stainless steels and nickel Ni-Resist castings ...... 6 bearing alloys in organic acids ...... 17 9008 Stainless steels for pumps, valves, and fittings ...... 7 10 064 Clad engineering...... 17 9009 Stainless steels for pulp and paper manufacturing ...... 7 10 065 Application of impressed current cathodic 9013 Stainless steels in ammonia production ...... 8 protection to stainless steel hot-water storage tanks ...... 18 9014 Design guidelines for the selection and use 10 066 Preventing stress-corrosion cracking of austenitic of stainless steels ...... 8 stainless steels in chemical plants ...... 18 9021 Role of stainless steel in petroleum refining ...... 8 10 068 Specifying stainless steel surface treatments ...... 18 9026 Stainless steels for evaporators-concentrators ...... 8 10 078 Electroplating on plastics .19 36

10 083 Corrosion performance of Ni-Cr-Fe alloys 1232 Fracture toughness and related characteristics in geothermal hypersaline brines ...... 20 of the cryogenic nickel steels ...... 4 10 084 Electroforming - a unique metal fabrication process ..... 20 1238 Low-temperature properties of nickel alloy steels ...... 4 10 085 Microbiologically influenced corrosion of 4368 Materials for cryogenic service - engineering stainless steels by water used for cooling and properties of austenitic stainless steels ...... 6 hydrostatic testing...... 20 10 030 Nine per cent nickel -28 years of reliable 11 004 Materials for saline water, desalination and service in liquefied natural gas containment ...... 13 oilfield brine pumps...... 20 10 067 Evaluation of decommisioned LNG storage 11 007 Guidelines for the welded fabrication of nickel tanks at Chula Vista, CA ...... 18 containing stainless steels for corrosion 14 004 Nickel steels in arctic service ...... 25 resistant services ...... 21 14 037 Welding stainless and 9% nickel steel 11 012 Guidelines for the welded fabrication of nickel cryogenic vessels ...... 28 alloys for corrosion-resistant service ...... 21 14 040 Fabrication techniques for successful 11 017 Ni-Hard material data and applications ...... 22 orbital tube welding ...... 28 11 018 Properties and applications of Ni-Resist and ductile Ni-Resist alloys ...... 22 DESALINATION 11 019 Stainless steel plumbing ...... 22 1240 The interrelation of corrosion and fouling of 12 001 Life-cycle cost benefits of constructing an metals in seawater ...... 4 FGD system with selected stainless steels and 1258 Corrosion fatigue properties of nickel-containing nickel-base alloys ...... 22 materials in seawater ...... 4 12 005 A report on the performance of stainless steel pipe 1280 Guide to the welding of copper-nickel alloys ...... 5 for water supply in underground soil environments ...... 23 4319 Copper-nickel and other alloys for desalination plants ...... 6 12 010 Stainless steel in swimming pool buildings .23 4353 Copper-nickel alloys - engineering properties 12 011 Design manual for structural stainless steel .23 and applications ...... 6 14 001 High performance alloys: how they are used offshore . 24 9029 Role of stainless steels in desalination ...... 9 14 004 Nickel steels in arctic service .25 10 003 Reverse osmosis - which stainless steel to use ...... 10 14 007 Evaluation of bleach plant piping materials .25 10 004 Fabrication and post-fabrication cleanup of 14 015 Ambient-temperature stress-corrosion cracking of stainless steels...... 10 austenitic stainless steel in swimming pools .26 10 011 Nickel-containing materials in marine and 14 017 Stress-corrosion cracking in nickel-base related environments ...... 11...... alloy weldments .26 10 085 Microbiologically influenced corrosion of 14 020 Weld fabrication of a 6% molybdenum alloy stainless steels by water used for cooling and to avoid corrosion in bleach plant service .26 hydrostatic testing ...... 20 14 021 Alloy 400 for use in high pressure feedwater heaters ...... 26 11 004 Materials for saline water, desalination and 14 023 Performance of highly alloyed materials in oilfield brine pumps ...... 20 chlorination bleaching ...... 26 11 019 Stainless steel plumbing .22 14 026 Corrosion behaviour of stainless steel, 12 007 Copper-nickel alloys - properties and applications . 23 nickel base alloy and titanium weldments in 14 034 Stainless steel reinforcing as corrosion protection . 28 chlorination and chlorine dioxide bleaching ...... 27 14 036 Welding duplex and super-duplex stainless steels . 28 14 027 Managing galvanic corrosion .27 14 040 Fabrication techniques for successful 14 028 Lambton's alloy lining .27 orbital tube welding...... 28 14 032 Recycling a railcar classic .27 14 041 Long life ambition ...... 28 14 033 Systemic nickel: the contribution made by 14 044 Stainless steel piping ...... 29 stainless steel cooking utensils .27 14 034 Stainless steel reinforcing as corrosion protection ...... 28 DUCTILE IRONS 14 035 The influence of risk analysis on the 242 Machining and grinding Ni-Resist and ductile economics of carbon steel and CRA clad flowlines ...... 28 Ni-Resist ...... I 14 036 Welding duplex and super-duplex stainless steels ...... 28 4077 Nickel SG iron - engineering properties ...... 6 14 037 Welding stainless and 9% nickel steel 4421 The welding of flake and spheroidal graphite cryogenic vessels...... 28 Ni-Resist castings ...... 6 14 040 Fabrication techniques for successful 10 018 Influence of carbide content on the stress corrosion orbital tube welding ...... 28 cracking of Ni-Resist cast irons in warm seawater ...... 11 14 041 Long life ambition ...... 28 11 018 Properties and applications of Ni-Resist and 14 043 Steeled against the elements - stainless steel doors ductile Ni-Resist alloys ...... 22 can stand up to fire and corrosive environments ...... 29 ELECTRICAL AND ELECTRONICS 14 044 Stainless steel piping ...... 29 14 045 The role of chlorine in high temperature corrosion 9015 Stainless steel solar collector panels ...... 8 in waste-to-energy plants...... 29 10 029 Nickel alloys in today's electronics industry ...... 13 14 047 A metallurgical approach to metal contact dermatitis ...... 29 10 041 Nickel-chromium alloys for electric 15 001 Nuclear service water piping, resistance heating ...... 15 the Salem Nuclear Generating Station ...... 29 10 060 High-performance nickel-containing 15 002 Nuclear service water piping, connector alloys ...... 17 Oskarshamn Nuclear Power Plant ...... 29 10 078 Electroplating on plastics .19 D-0003 Crevice corrosion engineering guide ...... 31 10 081 Properties and applications of electroless nickel . 19 10 084 Electroforming - a unique metal fabrication process . 20 CRYOGENICS 11 002 Nickel alloys for electronics .20 278 3½%2%nickel steel for low temperature service ...... I 13 002 Demand trends for nickel and nickel-containing 313 Austenitic chromium-nickel stainless steel at materials used in Japanese electronics industry . 24 subzero temperatures - mechanical and 14 003 Nickel aids chips' need for super clean water ...... 24 physical properties ...... I 14 040 Fabrication techniques for successful 328 Types 304 and 304L stainless steels for low orbital tube welding ...... 28 temperature service ...... I 14 043 Steeled against the elements - stainless steel doors 410 27% nickel-iron alloy for low temperature service ...... 2 can stand up to fire and corrosive environments ...... 29 1208 Welding 9% nickel steel - a review of the current practices ...... 4 37

ELECTROPLATING AND ELECTROFORMING 1279 Stress corrosion cracking behavior of wrought 10 036 A fundamental study of corrosion-resistant Fe-Cr-Ni alloys in a marine atmosphere ...... 5 zinc-nickel electroplating ...... 14 1285 Corrosion resistance of nickel-containing alloys 10 047 Nickel electroplating solutions ...... 15 in organic acids and related compounds ...... 5 10 048 Organic addition agents for nickel electroplating 1300 The corrosion resistance of nickel-containing solutions...... 15 alloys in flue gas desulfurization and other scrubbing processes ...... 5 10 049 Anodes for electrodeposition of nickel ...... 16 1318 The corrosion resistance of nickel-containing 10 050 Applications of decorative nickel plating .16 alloys in sulphuric acid and related compounds ...... 5 10 051 Applications of engineering nickel plating .16 10 001 Solving high-temperature problems in oil refineries 10 052 Nickel sulphamate solutions .16 and petrochemical plants ...... 10 10 053 Additions to sulphamate nickel solutions .16 10 005 Nickel in the process industries - an anxiety 10 054 Applications of electroforming .16 closet of materials selection monsters ...... 10 10 055 Electroless nickel coatings .16 10 011 Nickel-containing materials in marine and 10 078 Electroplating on plastics .19 related environments ...... 11...... 10 081 Properties and applications of electroless nickel . 19 10 012 Nickel-base alloys in the power industry ...... 11 10 016 Test techniques for pitting and crevice corrosion 10 084 Electroforming - a unique metal fabrication process .20 resistance of stainless steels and nickel-basealloys in 13 001 Zinc-nickel alloy electroplated steel coil and chloride-containing environments ...... 11 other precoated coil for use by the automotive industry: A review of literature published 10 019 Alloy selection for caustic soda service ...... 12 1983 to 1987 .24 10 020 Alloys to resist chlorine, hydrogen chloride and 14 002 Why zinc-nickel coated steels? . 24 hydrochloric acid ...... 12 14 005 Modem electroforming...... 25 10 024 The use of nickel stainless steels and nickel alloys in flue gas desulphurization systems 14 009 Electroless Ni coatings win on uniformity .25 in the United States ...... 12 14 012 Electroforming today...... 25 10 025 Flue gas desulphurization; the European scene ...... 12 14 022 Electrodeposited coatings of zinc-nickel .26 10 027 Welding and fabrication in nickel alloys in 14 024 A review of recent trends in nickel electroplating FGD systems ...... 13 technology in North America and Europe. 27 10 033 Nickel-containing alloy piping for offshore oil 14 031 Nickel alloy plating ...... 27 and gas production...... 13 10 034 Applications of centrifugally-cast alloy piping ENVIRONMENTAL, HEALTH AND SAFETY and pipe fittings in onshore and offshore oil and gas production...... 14 Communique (Periodical) ...... 29 10 035 Selection of corrosion-resistant alloy tubulars 10 046 Cleanability in relation to bacterial retention on for offshore applications ...... 14 unused and abraded domestic sink materials ...... 15 10 041 Nickel-chromium alloys for electric resistance 10 069 Effect of wiping and spray wash temperature on heating...... 15 bacterial retention of abraded domestic sink surface . 18 10 056 Practical guide to high-temperature alloys ...... 16 10 079 Effectiveness of sanitation with quaternary ammonium compound or chlorine on stainless steel 10 061 Development of mechanized field girth welding and other domestic food-preparation surfaces 19 of high-alloy corrosion-resistant pipeline materials ...... 17 10 080 Cleaning stainless steel surfaces prior to 10 071 Wrought and cast heat resistant stainless steels sanitary service .19 and nickel alloys for the refining and petrochemical industries ...... 18 10 082 Is "nickel" safe? A toxicology primer .19 10 075 Selection and performance of stainless steels and 11 019 Stainless steel plumbing .22 other nickel-bearing alloys in nitric acid ...... 19 13 004 Stainless steel demand for kitchen equipment in Japan 24 10 083 Corrosion performance of Ni-Cr-Fe alloys 14 008 Sinks of stainless clean best, beat bacteria .25 in geothermal hypersaline brines ...... 20 14 033 Systemic nickel: the contribution made by 11 004 Materials for saline water, desalination and stainless steel cooking utensils .27 oilfield brine pumps ...... 20 14 039 Purity of food cooked in stainless steel utensils ...... 28 11 008 Machining nickel alloys ...... 21 14 042 International harmonization related to 11 012 Guidelines for the welded fabrication of nickel persistence and bioavailability ...... 28 alloys for corrosion-resistant service ...... 21 14 043 Steeled against the elements - stainless steel doors 14 01 Versatility of high-alloyed Ni-Cr-Mo welding can stand up to fire and corrosive environments ...... 29 consumables ...... 25 14 047 A metallurgical approach to metal contact dermatitis ...... 29 14 017 Stress-corrosion cracking in nickel-base SR-0001 Nickel and nickel alloy articles that come into alloy weldments ...... 26 contact with the skin ...... 30 14 021 Alloy 400 for use in high pressure feedwater heaters ...... 26 SR-0003 Nickel pickup by food cooked in stainless steel utensils ...... 30 14 027 Managing galvanic corrosion ...... 27 SR-0004 Health studies of high nickel alloys workers 14 028 Lambton's alloy lining ...... 27 in the U.S ...... 30 14 029 Fabrication options for nickel-containing alloys SR-0005 Occupational exposure limits for nickel and in FGD service: guidelines for users ...... 27 nickel compounds ...... 30 14 037 Welding stainless and 9% nickel steel SR-0006 Coinage and nickel ...... 30 cryogenic vessels ...... 28 Safe use of nickel in the workplace - Health GUIDE 14 040 Fabrication techniques for successful (before ordering, please read abstract) ...... 30 orbital tube welding ...... 28 Safe use of nickel in the workplace - Health Guide SUMMARY 14 045 The role of chlorine in high temperature corrosion (before ordering, please read abstract) ...... 30 in waste-to-energy plants...... 29 Safe use of nickel in the workplace - Health BROCHURE 15 001 Nuclear service water piping, (before ordering, please read abstract) ...... 30 the Salem Nuclear Generating Station ...... 29 15 002 Nuclear service water piping, HIGH-NICKEL ALLOYS Oskarshamn Nuclear Power Plant ...... 29 393 High-temperature, high-strength nickel-base alloys ...... 2 515 Some nickel copper casting alloys HIGH-TEMPERATURE ALLOYS - engineering properties ...... 3 266 Heat-resistant castings, corrosion-resistant castings 517 Nickel-chromium alloy 610 and related their engineering properties and applications ...... 1...... casting alloys - engineering properties ...... 3 337 Alloy 713C technical data ...... I 38

393 High-temperature, high-strength nickel-base alloys ...... 2 9032 Stainless steel: Effective corrosion control in 483 IN-100 alloy - engineering properties ...... 3 water and waste-water treatment plants ...... 9 497 IN-738 alloy - preliminary data ...... 3 10 002 Evaluating installed cost of corrosion resistant piping ...... 10 517 Nickel-chromium alloy 610 and related casting alloys- engineering properties ...... 3 10 004 Fabrication and post-fabrication cleanup of stainless steels ...... 10 534 Machining and grinding several cast nickel- base high-temperature alloys ...... 3 10 008 H20: Nickel's contribution to distilled water, dams and 1181 Alloy design using second phases ...... 3 condensers ...... 10 10 011 Nickel-containing materials in marine and 1196 Cast heat-resistant alloys ...... 3 related environments ...... 11...... 2980 Austenitic chromium-nickel stainless steels at 10 018 Influence of carbide content on the stress corrosion elevated temperatures - mechanical and cracking of Ni-Resist cast irons in warm seawater ...... 11 physical properties...... 6 10 021 Procurement of quality stainless steel castings ...... 12 4383 IN-519 cast chromium-nickel-niobium heat- resisting steel - engineering properties ...... 6 10 022 The resistance of stainless steel, partly embedded in concrete, to corrosion by seawater ...... 12 9004 High-temperature characteristics of stainless steel ...... 7 10 034 Applications of centrifugally-cast alloy piping 9013 Stainless steels in ammonia production ...... 8 and pipe fittings in onshore and offshore oil 10 001 Solving high-temperature problems in oil and gas production...... 14 refineries and petrochemical plants ...... 10 10 035 Selection of corrosion-resistant alloy tubulars 10 031 Repair welding high-alloy furnace tubes ...... 13 for offshore applications ...... 14 10 034 Applications of centrifugally-cast alloy piping 10 040 The right metal for heat exchanger tubes ...... 14 and pipe fittings in onshore and offshore oil 10 044 Practical guide to using duplex stainless steels ...... 15 and gas production ...... 14 10 041 Nickel-chromium alloys for electric resistance 10 045 Practical guide to using marine fasteners ...... 15 heating...... 15 10 061 Development of mechanized field girth welding of high-alloy corrosion-resistant pipeline materials ...... 17 10 056 Practical guide to high-temperature alloys ...... 16 10 058 HP-M'odified furnace tubes for steam reformers 10 068 Specifying stainless steel surface treatments ...... 18 and steam crackers ...... 17 10 085 Microbiologically influenced corrosion of stainless steels by water used for cooling and 10 059 HP-Modified furnace tube market survey ...... 17 hydrostatic testing...... 20 10 071 Wrought and cast heat resistant stainless steels 11 003 Guidelines for selection of nickel stainless steels for and nickel alloys for the refining and marine environments, natural waters and brines ...... 20 petrochemical industries...... 18 11 004 Materials for saline water, desalination and 14 040 Fabrication techniques for successful oilfield brine pumps ...... 20 orbital tube welding ...... 28 11 018 Properties and applications of Ni-Resist and 14 043 Steeled against the elements - stainless steel doors ductile Ni-Resist alloys ...... 22 can stand up to fire and corrosive environments ...... 29 11 019 Stainless steel plumbing ...... 22 14 045 The role of chlorine in high temperature corrosion in waste-to-energy plants...... 29 12 002 Performance of tubular alloy heat exchangers in seawater service in the chemical process industries ..... 22 IRON-NICKEL ALLOYS 12 003 Guidelines for the use of copper alloys in seawater . 22 410 27% nickel-iron alloy for low-temperature service ...... 2 12 007 Copper-nickel alloys - properties and applications . 23 14 027 Managing galvanic corrosion .27 MARAGING STEELS 14 034 Stainless steel reinforcing as corrosion protection . 28 584 Welding of maraging steels ...... 3 14 036 Welding duplex and super-duplex stainless steels . 28 4419 18% nickel maraging steel - engineering properties ...... 6 14 040 Fabrication techniques for successful MARINE AND SHIPBUILDING orbital tube welding...... 28 14 041 Long life ambition ...... 28 515 Some nickel copper casting alloys - engineering properties ...... ,.3 14 043 Steeled against the elements - stainless steel doors can stand up to fire and corrosive environments ...... 29 1107 The design and installation of 90/10 copper- nickel seawater piping systems ...... 3 15 001 Nuclear service water piping. the Salem Nuclear Generating Station ...... 29 1240 The interrelation of corrosion and fouling of metals in seawater ...... 4 15 002 Nuclear service water piping, Oskarshamn Nuclear Power Plant ...... 29 1258 Corrosion fatigue properties of nickel-containing materials in seawater ...... 4 MINING AND CEMENT 1259 The successful use of austenitic stainless steels 70 Ni-Hard - engineering properties and applications ...... I in seawater ...... 4 1203 Six reasons for specifying nickel carburizing steels ...... 3 1265 CA-706 copper-nickel alloy hulls: the Copper Aariner'sexperience and economics ...... 5 1205 The role of nickel in carburizing steels ...... 4 1278 IN-787 - a precipitation hardening alloy steel, 1267 Abrasion-resistant castings for handling coal ...... 5 properties and applications ...... 5 1278 IN-787 - a precipitation hardening alloy steel, 1279 Stress corrosion cracking behavior of wrought properties and applications ...... 5 Fe-Cr-Ni alloys in a marine atmosphere ...... 5 4421 The welding of flake and spheroidal graphite 1280 Guide to the welding of copper-nickel alloys ...... 5 Ni-Resist castings ...... 6 4319 Copper-nickel and other alloys for desalination 9025 Stainless steel for bulk materials handling ...... 8 plants ...... 6 9026 Stainless steels for evaporators-concentrators ...... 8 4353 Copper-nickel alloys - engineering properties 11 017 Ni-Hard material data and applications ...... 22 and applications...... 6 11 018 Properties and applications of Ni-Resist and 4419 18% nickel maraging steel - engineering properties ...... 6 ductile Ni-Resist alloys ...... 22 4421 The welding of flake and spheroidal graphite 14 034 Stainless steel reinforcing as corrosion protection ...... 28 Ni-Resist castings ...... 6 14 036 Welding duplex and super-duplex stainless steels ...... 28 9005 Role of stainless steels in industrial heat exchangers ...... 7 14 041 Long life ambition ...... 28 9008 Stainless steels for pumps, valves, and fittings ...... 7 9030 A discussion of stainless steels for surface PETROLEUM AND GAS condensers and feedwater heater tubing ...... 9 1278 IN-787 - a precipitation hardening alloy steel, properties and applications ...... 5 39

4383 IN-519 cast chromium-nickel-niobium heat 9032 Stainless steel: Effective corrosion control in resisting steel - engineering properties ...... 6 water and waste-water treatment plants ...... 9 9013 Stainless steels in ammonia production ...... 8 10 003 Reverse osmosis - which stainless steel to use ...... 10 9021 Role of stainless steel in petroleum refining ...... 8 10 004 Fabrication and post-fabrication cleanup of 10 001 Solving high-temperature problems in oil stainless steels ...... 10 refineries and petrochemical plants ...... 10 10 007 Nickel's contribution in air pollution abatement ...... 10 10 004 Fabrication and post-fabrication cleanup of 10 008 HzO: Nickel's contribution to distilled water, stainless steels ...... 10 dams and condensers ...... 10 10 013 Opportunities for nickel in the oil and gas market 10 021 Procurement of quality stainless steel castings ...... 12 (I) introduction (2) deep sour gas production 10 023 Life-cycle comparison of alternative alloys (3) enhanced oil recovery (4) offshore ...... 11 for FGD components ...... 12 10 014 Welding status of duplex stainless steels 10 024 The use of nickel stainless steels and nickel for offshore applications ...... 11...... alloys in flue gas desulphurization systems in the 10 021 Procurement of quality stainless steel castings .12 United States ...... 12 10 030 Nine per cent nickel -28 years of reliable 10 025 Flue gas desulphurization; the European scene ...... 12 service in liquefied natural gas containment .13 10 027 Welding and fabrication in nickel alloys in 10 031 Repair welding high-alloy furnace tubes .13 FGD systems ...... 13 10 032 Practical guide to using 6Mo austenitic stainless steel . 13 10 068 Specifying stainless steel surface treatments ...... 18 10 033 Nickel-containing alloy piping for offshore oil 10 076 Guidelines for the use of stainless steel in and gas production .13 municipal waste water treatment plant ...... 19 10 034 Applications of centrifugally-cast alloy piping 10 079 Effectiveness of sanitation with quatemary and pipe fittings in onshore and offshore oil and ammonium compound or chlorine on stainless steel gas production .14 and other domestic food-preparation surfaces ...... 19 10 035 Selection of corrosion-resistant alloy tubulars 10 080 Cleaning stainless steel surfaces prior to for offshore applications .14 sanitary service ...... 19 10 042 Stainless steel for durability, fire-resistance 10 085 Microbiologically influenced corrosion of and safety...... 15 stainless steels by water used for cooling and 10 044 Practical guide to using duplex stainless steels ...... 15 hydrostatic testing...... 20 10 056 Practical guide to high-temperature alloys ...... 16 11 019 Stainless steel plumbing ...... 22 10 058 HP-Modified furnace tubes for steam reformers 12 001 Life-cycle cost benefits of constructing an and steam crackers ...... 17 FGD system with selected stainless steels and 10 059 HP-Modified furnace tube market survey ...... 17 nickel-base alloys ...... 22 10 061 Development of mechanized field girth welding 14 029 Fabrication options for nickel-containing alloys of high-alloy corrosion-resistant pipeline materials ...... 17 in FGD service: guidelines for users ...... 27 10 064 Clad engineering...... 17 14 033 Systemic nickel: the contribution made by stainless steel cooking utensils ...... 27 10 067 Evaluation of decommisioned LNG storage tanks at Chula Vista, CA ...... 18 14 036 Welding Duplex And Super-Duplex Stainless Steels ...... 28 10 068 Specifying stainless steel surface treatments ...... 18 14 040 Fabrication techniques for successful orbital tube welding ...... 28 10 071 Wrought and cast heat resistant stainless steels and nickel alloys for the refining and 14 042 International harmonization related to petrochemical industries ...... 18 persistence and bioavailability ...... 28 10 073 Selection guidelines for corrosion resistant alloys 14 044 Stainless steel piping ...... 29 in the oil and gas industry ...... 18 14 045 The role of chlorine in high temperature corrosion 10 085 Microbiologically influenced corrosion of in waste-to-energy plants ...... 29 stainless steels by water used for cooling and SR-0005 Occupational exposure limits for nickel and hydrostatic testing...... 20 nickel compounds...... 30 11 004 Materials for saline water, desalination and POWDERS oilfield brine pumps...... 20 11 006 Nickel in powder metallurgy steels ...... 21 12 007 Copper-nickel alloys - properties and applications ...... 23 12 011 Design manual for structural stainless steel ...... 23 POWER 14 001 High performance alloys: how they are used 375 Copper-nickel alloys for feedwater heater service ...... 2 offshore...... 24 1213 A discussion on stainless steels for surface condenser and 14 004 Nickel steels in arctic service ...... 25 feedwater heater tubing ...... 4 14 017 Stress-corrosion cracking in nickel-base 1240 The interrelation of corrosion and fouling of metals alloy weldments ...... 26 in seawater ...... 4 14 034 Stainless steel reinforcing as corrosion protection ...... 28 1267 Abrasion-resistant castings for handling coal ...... 5 14 035 The influence of risk analysis on the 1300 The corrosion resistance of nickel-containing economics of carbon steel and CRA clad flowlines ...... 28 alloys in flue gas desulfurization and other 14 036 Welding duplex and super-duplex stainless steels ...... 28 scrubbing processes ...... 5 14 037 Welding stainless and 9% nickel steel 1304 The influence of corrosion and fouling on cryogenic vessels ...... 28 steam condenser performance ...... 5 14 040 Fabrication techniques for successful 1305 The resistance of copper-nickel alloys to orbital tube welding ...... 28 ammonia corrosion in simulated steam 14 041 Long life ambition ...... 28 condenser environments ...... 5 14 043 Steeled against the elements - stainless steel doors 4353 Copper-nickel alloys - engineering properties can stand up to fire and corrosive environments ...... 29 and applications ...... 6 V-0001 Stainless steel: the effective solution ...... 31 9005 Role of stainless steels in industrial heat exchangers ...... 7 9008 Stainless steels for pumps, valves, and fittings ...... 7 POLLUTION CONTROL 9015 Stainless steel solar collector panels ...... 8 1300 The corrosion resistance of nickel-containing 9025 Stainless steel for bulk materials handling ...... 8 alloys in flue gas desulfurization and other scrubbing processes ...... 5 9030 A discussion of stainless steels for surface condensers and feedwater heater tubing ...... 9 9008 Stainless steels for pumps, valves, and fittings ...... 7 9032 Stainless steel: Effective corrosion control in 9026 Stainless steels for evaporators-concentrators ...... 8 water and waste-water treatment plants ...... 9 40

10 004 Fabrication and post-fabrication cleanup of 2978 Austenitic chromium-nickel stainless steels at stainless steels ...... 10 ambient temperatures - mechanical and 10 008 H20: Nickel's contribution to distilled water, physical properties...... 6 dams and condensers ...... 10 4421 The welding of flake and spheroidal graphite 10 012 Nickel-base alloys in the power industry ...... 11...... 1 Ni-Resist castings ...... 6 10 021 Procurement of quality stainless steel castings ...... _12 9003 Stainless steel fasteners - a systematic approach 10 023 Life-cycle comparison of alternative alloys to their selection ...... 7 for FGD components ...... 12 9005 Role of stainless steels in industrial heat exchangers ...... 7 10 024 The use of nickel stainless steels and nickel 9008 Stainless steels for pumps, valves, and fittings ...... 7 alloys in flue gas desulphurization systems in 9009 Stainless steels for pulp and paper manufacturing ...... 7 the United States ...... 12 9024 Design guidelines for stainless steel in piping systems ...... 8 10 025 Flue gas desulphurization; the European scene ...... 12 9025 Stainless steel for bulk materials handling ...... 8...... 8 10 027 Welding and fabrication in nickel alloys in 9026 Stainless steels for evaporators/concentrators ...... 8 FGD systems ...... 13 10 002 Evaluating installed cost of corrosion-resistant piping .... 10 10 032 Practical guide to using 6Mo austenitic stainless steel ...... 13 10 003 Reverse osmosis - which stainless steel to use? ...... I 0... 10 039 Stainless steel sheet lining of steel tanks and 10 004 Fabrication and post-fabrication cleanup of pressure vessels ...... 14 stainless steels ...... 10 10 040 The ight metal for heat exchanger tubes ...... 14 10 006 High-performance austenitic stainless steels in the pulp and paper industry ...... 10 10 043 Design, water factors affect service-water piping materials ...... 15 10 017 Stainless steel is cost-equivalent to FRP for use in the bleach plant...... 11 10 044 Practical guide to using duplex stainless steels ...... 15 10 032 Practical guide to using 6Mo austenitic stainless steel ..... 13 10 056 Practical guide to high-temperature alloys ...... 16 10 038 Development of abrasion-resistant, nickel 10 068 Specifying stainless steel surface treatments ...... 18 containing alloy white irons of high hardness ...... 14 10 083 Corrosion performance of Ni-Cr-Fe alloys 10 040 The right metal for heat exchanger tubes ...... 14 in geothermal hypersaline brines ...... 20 10 044 Practical guide to using duplex stainless steels ...... 15 10 085 Microbiologically influenced corrosion of stainless steels by water used for cooling and 10 057 Selection and performance of stainless steels hydrostatic testing ...... 20 and other nickel-bearing alloys in sulphuric acid ...... 17 11 004 Materials for saline water, desalination and 10 063 Selection and use of stainless steels and nickel oilfield brine pumps...... 20 bearing alloys in organic acids ...... 17 11 010 Nickel-containing materials for water control 10 068 Specifying stainless steel surface treatments ...... 18 applications ...... 21 10 085 Microbiologically influenced corrosion of 11 011 Proceedings of materials workshops for the stainless steels by water used for cooling and power industry ...... 21 hydrostatic testing...... 20 It 017 Ni-Hard material data and applications ...... 22 11 003 Guidelines for selection of nickel stainless steels for marine environments, natural waters and brines ...... 20 12 001 Life-cycle cost benefits of constructing an FGD system with selected stainless steels and 11 007 Guidelines for the welded fabrication of nickel-base alloys ...... 22 nickel-containing stainless steels for corrosion-resistant services ...... 21 12 002 Performance of tubular alloy heat exchangers in seawater service in the chemical process industries ..... 22 11 010 Nickel-containing materials for water control applications...... 21 12 003 Guidelines for the use of copper alloys in seawater . 22 11 017 Ni-Hard material data and applications ...... 22 12 007 Copper-nickel alloys - properties and applications ...... 23 11 018 Properties and applications of Ni-Resist and 13 007 Flue gas desulphurization in Japan ...... 24 ductile Ni-Resist alloys ...... 22 14 006 Sedimentation in condensers and heat exchangers: 12 002 Performance of tubular alloy heat exchangers Causes and effects ...... 25 in seawater service in the chemical process industries ..... 22 14 021 Alloy 400 for use in high pressure feedwater heaters ...... 26 14 007 Evaluation of bleach plant piping materials ...... 25 14 028 Lanibton's alloy lining ...... 27 14 013 Corrosion of metallic and non 14 029 Fabrication options for nickel-containing alloys metallic piping for bleach plant D stage filtrate ...... 25 in FGD service: guidelines for users ...... 27 14 014 Performance of highly-alloyed materials in 14 034 Stainless steel reinforcing as corrosion protection ...... 28 chlorine dioxide bleaching ...... 26 14 036 Welding duplex and super-duplex stainless steels ...... 28 14 018 Guidelines for welding dissimilar metals ...... 26 14 037 Welding stainless and 9% nickel steel 14 019 Resist chlorides, retain strength and ductility cryogenic vessels ...... 28 with duplex stainless steel alloys ...... 26 14 040 Fabrication techniques for successful 14 020 Weld fabrication of a 6% molybdenum alloy orbital tube welding ...... 28 to avoid corrosion in bleach plant service ...... 26 14 041 Long life ambition ...... 28 14 023 Performance of highly alloyed materials in 14 044 Stainless steel piping ...... 29 chlorination bleaching ...... 26 14 045 The role of chlorine in high temperature corrosion 14 026 Corrosion behaviour of stainless steel, nickel- in waste-to-energy plants...... 29 base alloy and titanium weldments in chlorination 15 001 Nuclear service water piping, and chlorine dioxide bleaching ...... 27 the Salem Nuclear Generating Station ...... 29 14 034 Stainless steel reinforcing as corrosion protection ...... 28 15 002 Nuclear service water piping, 14 036 Welding duplex and super-duplex stainless steels ...... 28 Oskarshamn Nuclear Power Plant ...... 29 14 040 Fabrication techniques for successful orbital tube welding ...... 28 PULP AND PAPER 14 041 Long life ambition ...... 28 70 Ni-Hard - engineering properties and applications ...... I 14 044 Stainless steel piping ...... 29 242 Machining and grinding Ni-Resist and ductile Ni-Resist ...... I RAIL AND HIGHWAY TRANSPORTATION 959 Standard forms and finishes for stainless steels ...... 3 1278 IN-787 a precipitation hardening alloy steel 1130 Machining the austenitic chromium-nickel properties and applications ...... 5...... 5 stainless steels...... 3 9018 Stainless steels for mass transportation ...... 8 1259 The successful use of austenitic stainless steels 11 019 Stainless steel plumbing ...... 22 in seawater ...... 4 13 006 Development of stainless steel railroad cars in Japan . 24 41

14 025 Stainless steel railcars reduce weight, save energy ...... 27 9021 Role of stainless steel in petroleum refining ...... 8 14 032 Recycling a railcar classic ...... 27 9022 Automotive stainless steels ...... 8 14 034 Stainless steel reinforcing as corrosion protection ...... 28 9024 Design guidelines for stainless steel in piping systems ...... 8 14 036 Welding duplex and super-duplex stainless steels ...... 28 9025 Stainless steel for bulk materials handling ...... 8 14 037 Welding stainless and 9% nickel steel 9026 Stainless steels for evaporators-concentrators ...... 8 cryogenic vessels ...... 28 9029 Role of stainless steels in desalination ...... 9 14 040 Fabrication techniques for successful 9030 A discussion of stainless steels for surface orbital tube welding ...... 28 condensers and feedwater heater tubing ...... 9 14 041 Long life ambition .28 9031 Stainless steel - suggested practices for roofing, 14 046 Impact performance of model spot-welded flashing, copings, fascias, gravel stops, drainage ...... 9 stainless steel structures...... 29 9032 Stainless steel: Effective corrosion control in water and waste-water treatment plants ...... 9 STAINLESS STEELS 9034 Stainless steel membrane roof ...... 9 266 Heat resistant castings, corrosion-resistant castings, 10 003 Reverse osmosis - which stainless steel to use ...... 10 their engineering properties and applications . 10 004 Fabrication and post-fabrication cleanup of 313 Austenitic chromium-nickel stainless steel at subzero stainless steels...... 10 temperatures - mechanical and physical properties . 10 005 Nickel in the process industries - an anxiety 318 Corrosion resistance of austenitic chromium closet of materials selection monsters ...... 10 nickel stainless steels in atmospheric environments . 10 006 High-performance austenitic stainless steels 328 Types 304 and 304L stainless steels for low in the pulp and paper industry ...... 10 temperature service...... I 10 008 H20: Nickel's contribution to distilled water, 428 Fabrication of chromium-nickel stainless steel . 2 dams and condensers ...... 10 959 Standard forms and finishes for stainless steels . 3 10 009 Burgers, fries, Coke and stainless steel ...... 10 1130 Machining the austenitic chromium-nickel 10 010 Architecture - a demanding market for stainless steels...... 3 stainless steel ...... 11 1213 A discussion of stainless steels for surface 10 011 Nickel-containing materials in marine and condenser and feedwater heater tubing . 4 related environments ...... II...... 1220 Specifications and foreign equivalents for 10 013 Opportunities for nickel in the oil and gas market austenitic chromium-nickel stainless steels . 4 (1) introduction (2) deep sour gas production 1229 Standard wrought austenitic stainless steels . 4 (3) enhanced oil recovery (4) offshore ...... II 1259 The successful use of austenitic stainless steels in 10 014 Welding status of duplex stainless steels seawater .4 for offshore applications ...... II 1262 Resistance of stainless steel to corrosion in 10 015 Alloy selection in wet process phosphoric acid plants ..... 11 naturally occurring waters .4 10 016 Test techniques for pitting and crevice corrosion 1279 Stress corrosion cracking behavior of wrought resistance of stainless steels and nickel-base Fe-Cr-Ni alloys in a marine atmosphere . 5 alloys in chloride-containing environments ...... 11 1285 Corrosion resistance of nickel-containing alloys 10 017 Stainless steel is cost-equivalent to FRP for in organic acids and related compounds .5 use in the bleach plant ...... 11 1300 The corrosion resistance of nickel-containing 10 019 Alloy selection for caustic soda service ...... 12 alloys in flue gas desulfurization and other 10 020 Alloys to resist chlorine, hydrogen chloride and scrubbing processes .5 hydrochloric acid ...... 12 2828 Corrosion resistance of the austenitic chromium 10 021 Procurement of quality stainless steel castings ...... 12 nickel stainless steels in chemical environments . 6 10 022 The resistance of stainless steel, partly embedded 2978 Austenitic chromium-nickel stainless steels in concrete, to corrosion by seawater ...... 12 at ambient temperatures - mechanical and physical properties...... 6 10 023 Life-cycle comparison of alternative alloys for FGD components ...... 12 2980 Austenitic chromium-nickel stainless steels at elevated temperatures - mechanical and 10 024 The use of nickel stainless steels and nickel alloys physical properties...... 6 in flue gas desulphurization systems in the United States ...... 12 4368 Materials for cryogenic service - engineering properties of austenitic stainless steels . 6 10 025 Flue gas desulphurization; the European scene ...... 12 4383 I N-519 cast chromium-nickel-niobium heat 10 026 Fabrication and metallurgical experience in resisting steel - engineering properties . 6 stainless steel process vessels exposed to corrosive aqueous environments ...... 13 9001 Cleaning and descaling stainless steel . 7 10 032 Practical guide to using 6Mo austenitic 9002 Welding of stainless steels and other joining stainless steel ...... 13 methods .7 10 033 Nickel-containing alloy piping for offshore oil 9003 Stainless steel fasteners - a systematic approach and gas production...... 13 to their selection .7 10 034 Applications of centrifugally-cast alloy piping 9004 High-temperature characteristics of stainless steel . 7 and pipe fittings in onshore and offshore oil and 9005 Role of stainless steels in industrial heat exchangers .7 gas production ...... 14 9006 Review of the wear and galling characteristics of 10 035 Selection of corrosion-resistant alloy tubulars for stainless steels .7 offshore applications ...... 14 9008 Stainless steels for pumps, valves, and fittings . 7 10 037 Stainless steel in architecture ...... 14 9009 Stainless steels for pulp and paper manufacturing . 7 10 039 Stainless steel sheet lining of steel tanks and 9010 Stainless steels for building exteriors . 7 pressure vessels ...... 14 9011 Stainless steels for machining .7 10 040 The right metal for beat exchanger tubes ...... 14 9012 Finishes for stainless steels...... 7 10 042 Stainless steel for durability. fire-resistance and safety ...15 9013 Stainless steels in ammonia production . 8 10 044 Practical guide to using duplex stainless steels ...... 15 9014 Design guidelines for the selection and use 10 046 Cleanability in relation to bacterial retention on of stainless steels .8 unused and abraded domestic sink materials ...... 15 9015 Stainless steel solar collector panels .8 10 057 Selection and performance of stainless steels and 9016 Stainless steel forgings .8 other nickel-bearing alloys in sulphuric acid ...... 17 9018 Stainless steels for mass transportation . 8 10 061 Development of mechanized field girth welding of high-alloy corrosion-resistant pipeline materials ...... 17 9019 Cold forming stainless steel bar and wire . 8 42

10 063 Selection and use of stainless steels and nickel 14 019 Resist chlorides, retain strength and ductility bearing alloys in organic acids ...... 17 with duplex stainless steel alloys ...... 26 10 065 Application of impressed current cathodic 14 020 Weld fabrication of a 6% molybdenum alloy to protection to stainless steel hot-water storage tanks ...... 18 avoid corrosion in bleach plant service ...... 26 10 066 Preventing stress-corrosion cracking of 14 023 Performance of highly alloyed materials in austenitic stainless steels in chemical plants ...... 18 chlorination bleaching ...... 26 10 068 Specifying stainless steel surface treatments ...... 18 14 025 Stainless steel railcars reduce weight, save energy ...... 27 10 071 Wrought and cast heat resistant stainless steels 14 027 Managing galvanic corrosion ...... 27 and nickel alloys for the refining and 14 029 Fabrication options for nickel-containing alloys in petrochemical industries ...... 18 FGD service: guidelines for users ...... 27 10 073 Selection guidelines for corrosion resistant alloys 14 030 Water tank built to last 60 years ...... 27 in the oil and gas industry ...... 18 14 032 Recycling a railcar classic ...... 27 10 075 Selection and performance of stainless steels and 14 033 Systemic nickel: the contribution made by other nickel-bearing alloys in nitric acid ...... 19 stainless steel cooking utensils ...... 27 10 076 Guidelines for the use of stainless steel in 14 034 Stainless steel reinforcing as corrosion protection ...... 28 municipal waste water treatment plants ...... 19 14 035 The influence of risk analysis on the 10 077 Stainless steels for bioprocessing ...... 19 economics of carbon steel and CRA clad flowlines ...... 28 10 079 Effectiveness of sanitation with quaternary 14 036 Welding duplex and super-duplex stainless steels ...... 28 ammonium compound or chlorine on stainless steel and other domestic food-preparation surfaces ...... 19 14 037 Welding stainless and 9% nickel steel cryogenic vessels ...... 28 10080 Cleaning stainless steel surfaces prior to sanitary service ...... 19 14 039 Purity of food cooked in stainless steel utensils ...... 28 10 083 Corrosion performance of Ni-Cr-Fe alloys 14 040 Fabrication techniques for successful in geothermal hypersaline brines ...... 20 orbital tube welding ...... 28 10 085 Microbiologically influenced corrosion of 14 041 Long life ambition ...... 28 stainless steels by water used for cooling and 14 043 Steeled against the elements - stainless steel doors hydrostatic testing...... 20 can stand up to fire and corrosive environments ...... 29 11 003 Guidelines for selection of nickel stainless steels 14 044 Stainless steel piping ...... 29 for marine environments, natural waters and brines ...... 20 14 045 The role of chlorine in high temperature corrosion 11 004 Materials for saline water, desalination and in waste-to-energy plants...... 29 oilfield brine pumps...... 20 14 046 Impact performance of model spot-welded 11 007 Guidelines for the welded fabrication of stainless steel structures...... 29 nickel-containing stainless steels for corrosion 14 047 A metallurgical approach to metal contact dermatitis ...... 29 resistant services ...... 21 15 001 Nuclear service water piping, 11 013 Stainless steel in architecture, building the Salem Nuclear Generating Station ...... 29 and construction - guidelines for roofs, floors 15 002 Nuclear service water piping, and handrails...... 21 Oskarshamn Nuclear Power Plant ...... 29 11 014 Stainless steel in architecture, building and D-0001 Stainless steel information and design data - construction - guidelines for maintenance North American edition ...... 31 and cleaning ...... 21 D-0002 Guide to stainless steels -international edition ...... 31 11 015 Stainless steel in architecture, building and construction - guidelines for building exteriors ...... 21 SR-0005 Occupational exposure limits for nickel and nickel compounds ...... 30 11 016 Directory of North American suppliers of stainless steel products for building and construction ...... 22 V-0001 Stainless steel: the effective solution ...... 31 11 019 Stainless steel plumbing ...... 22 V-0002 Fresh approaches to mold steel selection ...... 31 12 001 Life-cycle cost benefits of constructing an WELDING AND FABRICATION FGD system with selected stainless steels and nickel-base alloys ...... 22 242 Machining and grinding Ni-Resist and ductile Ni-Resist ...... I 12 004 Answers for architects who design for beauty performance, utility and prestige with nickel 428 Fabrication of chromium-nickel stainless steel stainless steel ...... 22 (300 series) ...... 2 12 005 A report on the performance of stainless steel 534 Machining and grinding several cast nickel pipe for water supply in underground soil base high-temperature alloys ...... 3 environments ...... 23 584 Welding of maraging steels ...... 3 12 006 Technical manual for the design and construction 1130 Machining the austenitic chromium-nickel of roofs of stainless steel sheet ...... 23 stainless steels...... 3 12 008 Piping manual for stainless steel pipes for buildings ...... 23 1208 Welding 9% nickel steel - a review of the 12 009 Advantages for architects who design for beauty, current practices ...... 4 permanence, utility and prestige with nickel 1280 Guide to the welding of copper-nickel alloys ...... 5 containing stainless steel; an architect's guide 4368 Materials for cryogenic service - engineering on corrosion resistance ...... 23 properties of austenitic stainless steels ...... 6 12010 Stainless steel in swimming pool buildings ...... 23 4421 The welding of flake and spheroidal graphite 12 011 Design manual for structural stainless steel ...... 23 Ni-Resist castings ...... 6 13 003 Development of resin-coated stainless steel in Japan . 24 9002 Welding of stainless steels and other joining 13 004 Stainless steel demand for kitchen equipment in Japan 24 methods ...... 7 13 005 Application of Inco-colored stainless steel in Japan . 24 9011 Stainless steels for machining ...... 7 13 006 Development of stainless steel railroad cars in Japan . 24 9016 Stainless steel forgings ...... 8...... 8 13 007 Flue gas desulphurization in Japan .24 9019 Cold forming stainless steel bar and wire ...... 8 14 003 Nickel aids chips' need for super clean water .24 9031 Stainless steel - suggested practices for roofing flashing, copings, fascias, gravel stops, drainage ...... 9 14 008 Sinks of stainless clean best, beat bacteria .25 9034 Stainless steel membrane roof ...... 9 14 010 Save $US50 000 using stainless pipe instead of ductile iron .25 10 004 Fabrication and post-fabrication cleanup of stainless steels...... 10 14 014 Performance of highly-alloyed materials in chlorine dioxide bleaching .26 10 014 Welding status of duplex stainless steels for offshore applications ...... 11 14 015 Ambient-temperature stress-corrosion cracking of austenitic stainless steel in swimming pools . 26 10 021 Procurement of quality stainless steel castings .12 Sedimentation in condensers and heat exchangers: causes and effects

Reprinted from Power Engineering June 1985 edition

NiDI NICKEL DEVELOPMENT INSTITUTE NiDI Reprint Series NO 14 006 Sedimentation in condensers and heat exchangers: causes and effects

Little attention has been given to the important effect of low velocities on condenser and heat exchanger tubing performance. In particular, debris plays a critical role in inlet-end erosion-corrosion, and sedimentation left unremoved significantly hinders heat transfer

By ARTHUR H. TUTHILL, Tuthill Associates, Inc.

For most condensers the design velocity falls in the 6-8 fps range. Minimum veloc- Table 1. Critical crevice solution for series of highly alloyed materials- Molal (CIF and pH for initiation of crevice corrosion (J. W. Oldfield). ities are rarely specified, but low velocities do occur in some tubes due to inevita- Material Cr Ni Mo Cu Other Molal (CI-) pH ble variations in actual velocities around Type 316 18.5 10.0 2.6 4.0 1.65 the nominal velocity. The number of Proprietary 20.5 40.0 2.5 2.1 1.0 Ti 4.0 1.45 tubes that encounter low velocities in- Proprietary 27.5 3.5 2.0 0.46 Cb 4.0 1.25 creases considerably during the winter Type 317 17.6 13.8 3.5 4.0 1.35 months when less flow is needed to trans- Proprietary 20.1 24.9 4.5 1.5 4.0 1.25 fer the same amount of heat. Proprietary 20.4 23.6 6.5 5.0 0.95 In many heat exchangers the design velocity is lower than 6 fps-as low as 1-2 Proprietary 22.0 61.5 9.0 6.0 0.0 fps in some that recently came to the Proprietary 14.9 58.2 14.2 4.0 W writer's attention. The seeming lack of 2.1 Co 6.0 0.0 attention to velocity in heat exchangers in some cases, as compared to condensers, may be due to the practice of selecting standard sizes from a catalog rather than using a functional design approach. Whatever the reason, low velocities in stainless steel and copper alloy tubed condensers and heat exchangers have been the root cause of unexpected and un- r scheduled shutdowns, with all their at- tendant problems and expense. Unfortu- nately, the root cause-low velocity-is frequently lost sight of in the rush to retube and get the unit back on stream, and so failures tend to repeat. Low velocities lead to sedimentation and loss of heat transfer capability. If the unit is over-designed and the sediment left unremoved for many months, the probability of under-sediment corrosion of stainless steel and copper alloy tubes increases significantly. Even in "clean" ~~~~~~~~~~~~~~~~~~~~hs 1%hW:`I:waters there are always some particulates 3D ;u T.~fuie9 tl$~l o iorolnorto in suspension. These particulates have a c2encI xactaa~ E9,C nie1t e3t settling rate determined by their size, shape and density. The velocity of the water must be high enough to sweep the /I 12 13 14 particulate matter through the tube be- Logi fore it settles out in contact with the tube and remains there. Tube length can have a major influence on sedimentation. The longer the tube, .-. the higher the velocity needed to sweep ffi W .nra-iatnn...... *"#flfl , :-.-~nm rqntftnf~ n particulate matter through before it set- .o,.ation .,,ch can occu- ...... -mM-. i iti . -i ties out. Configuration of the unit-once- through, two-pass, U-tube, etc-also ex- erts an influence on whether the particle rapidly depleted, hydrolysis of metal ions is consistent with the many variations in posit corrosion was found in some heat reduces the pH and creates a charge im- the incidence of under-sediment corrosion exchangers after only a year's service. It balance. Chloride ions migrate into the reported and observed in practice. The developed that these units had been de- crevice to balance the charge (Figure 2). crevice gap (tightness) and the stability signed with flow rates of only 1-2 fps. So If the pH and chloride ion content of the crevice conditions during the time many of the tubes were plugged with reach critical values, film breakdown and necessary for initiation are of critical im- sediment that heat transfer was seriously crevice corrosion will be initiated. Table I portance. A loose sandy sediment is un- impaired. The units had excess heat (from Oldfield's work) shows the critical likely to cause crevice attack, whereas a transfer capability and the operating pH and chloride ion concentration for a thick sticky sediment which effectively forces failed to recognize the need to range of common stainless steels and shields the creviced area from the bulk clean until failures occurred. higher alloys (Ref. 5 and 6). environment may lead to crevice attack. A minimum flow rate of 3 fps is suffi- The very high concentrations of chlo- cient to sweep most of the sediment ride ions required for breakdown can only Preventing corrosion through most of the tubes most of the occur in very tight, very stable crevices Keeping the velocity up sufficiently to time. Since particulates do not come pre- where the crevice environment is com- sweep most of the particulate matter packaged in a single size, there is a con- pletely shielded from the bulk environ- through the tube and regular scheduled siderable range in particulate settling ment. Movement of either component of removal of the remaining particulates rates. The differences in tube length and the crevice will upset the conditions nec- will prevent under-sediment corrosion as configuration (once-through, two-pass essary for crevice corrosion initiation. well as improve heat transfer capability. and U-tube design) also influence the Failure to reach "critical" pH and chlo- The need for periodic cleaning seems self- amount of sediment deposited at any giv- ride conditions in the crevice will result in evident, yet in practice there is a wide en flow rate. Generally a minimum de- no breakdown and no crevice attack. The variation in the frequency with which sign velocity of about 5 fps, maintained in stringent conditions needed for break- heat exchangers and condensers are operation, will keep the actual velocity in down to occur are not reached in every opened and cleaned. most tubes above the 3 fps minimum nec- crevice. In many instances they are The author has personally investigated essary to minimize deposition of sediment reached only in a small percent of the cases where copper alloy tubing in heat and biofouling. Sediment that is not I total number of possible crevice sites. In exchangers and in desalination units has swept through can be removed only by practice the incidence of crevice attack not been opened and cleaned for more opening and manually cleaning, and this varies considerably even though the con- than five years. Operating forces appar- should be done on a regular schedule for ditions are seemingly similar. ently assumed that since waters were rel- both heat exchangers and condensers. a Kain, Tuthill and Hoxie have shown atively clean with little visible debris, The interval between condenser clean- that the incidence of crevice corrosion on opening and cleaning was unnecessary. ings is normally determined by the falloff type 304 in natural waters is vanishingly However, particulate matter was present in heat transfer capability and varies I small at chloride concentrations below although the cooling waters were visibly from a few weeks to a year or more. about 200 ppm and equally small for type clean. The copper alloy tubing was deeply Monthly to quarterly cleanings seem to 316 below 1000 ppm (Ref. 7). Above pitted beneath the sediments deposited in be associated with "normal" condenser these chloride concentrations initiation the tubing-in some instances to the operation and good tubing performance was found to occur in a small percentage point of penetration. Replacement was although the relationship is, at best, ap- I of very tight crevices (Figure 3). the only option. proximate. The writer's experience would The fact that crevice corrosion did not In two other and unrelated cases the suggest that deferring sediment removal occur in all of the crevices all of the time author has investigated, severe under-de- beyond six months greatly increases the 2 Wall shear stress, dyne/cm Velocity in tube at normal 250 __ portion and at the lodgement (nsi 8 _

U N 0 0.003 0.U7 U.U3 0.1 0.3 1.0 Inlet end L/D Ratio of flow area around the' lodgement of foreign body (a/A)

Figure 4. Variation inshear stress between flowing seawater Figure 5. Variation invelocity around an obstruction intube and metal wall with distance from the inlet end (Ref. 8). (from Ref. 8).

I- __ probability of under-sediment corrosion alloys have to inlet end erosion-corrosion, clean open tubes. It is little wonder that of copper alloy and stainless steel tubes. it is not uncommon for these alloys, par- inlet end erosion-corrosion accounts for More highly alloyed stainless steel alloys ticularly the C70600 alloy, to suffer inlet such a high proportion of copper alloy and titanium do have greater tolerance end damage in saline waters. tube problems. for under-sediment corrosion than types Debris is believed to be the reason for There are remedies. Since inlet end 304 and 316 and the copper base alloys. the tube end erosion-corrosion damage debris is found in systems where the Since sediment must be removed in order the C70600 and C71500 alloys some- screens are well maintained, strainers to to restore heat transfer capability, regu- times suffer. When the condenser is remove more of the debris that manages lar cleaning would appear to be more opened for cleaning and inspection, it is to get past the screens can be very helpful. sensible than upgrading to cope with uncommon to find sticks, stones, glass, Indeed, the use of strainers seems to be der-sediment corrosion in most instances. shells and similar items lodged in many of increasing. Another option is to use mate- the tube ends and others on the floor of rials more tolerant of erosion-corrosion Inlet end erosion-corrosion the waterbox. Such debris is common such as C72200 alloy, stainless steel, the The role debris plays in inlet end erosion- even in relatively clean waters where the new ferritics or titanium. END corrosion also deserves more attention screens are well maintained. than it has yet received. It is well known Seemingly, such large debris should that inlet end erosion-corrosion effects not get through the much smaller open- are responsible for the majority, perhaps ings in the screens. Nevertheless, it is References 1. LaQue, F. L., Marine Corrosion, John Wi- as much as two-thirds, of copper alloy there in the tube ends and on the floor of ley and Sons, Inc., 1975. tube failures. Nagata and Sato have the water box when the condenser is 2. Bulow, C. L., "Use of Copper Base Alloys in shown that the shear force between the opened. Inlet end debris is removed in Marine Services," Naval Engineers Journal. film of flowing water next to the tube wall order to clean the tubes and usually goes 77 (3) 470-482, June 1965. 3. Syrett, B. C., 'Sulfide Attack in Steam and the tube wall itself at the inlet end is unnoted in tube end failure reports. Over- Surface Condensers," Proceedings of Second double that further down the tube (Fig- looking tube end debris in failure reports International Conference on Environmental ure 4, Ref. 8). and failure analyses is undoubtedly due to Degradation of Engineering Materials in an Efird has measured the critical shear the fact that the debris is no longer pre- Aggressive Environment, 1981 pp 3-14. 5. Oldfield, J. W. and W. H. Sutton, Brit. stress for the common copper tubing al- sent when the tubes are examined in the Corrs. J. 13 (2), 103, 1978. loys (Table 2). The shear stress at the laboratory. If the report is prepared by an 6. Oldfield, J. W. and B. Todd, "The Use of inlet end is between 200 and 250 outside laboratory, the people making the Stainless Steels in MSF Desalination Plants," dynes/cm' for a 2-mps (6.5 fps) flow rate analysis may not even be aware that tube Arab Water Technology Conference, Dubai, November 1981. (Figure 4). Efird's table indicates the end debris was present. 7. Kain, R. M., A. H. Tuthill, and E. C. Hoxie, critical shear stress for C68700 Al-Brass The drastic effect that inlet end debris "The Resistance of Types 304 and 316 Stain- alloy is 192 dynes/cm'. Based on Efird's can have on inlet end erosion-corrosion is less Steels to Crevice Corrosion in Natural estimates of the critical shear stress, alu- clear in another chart from Natata and Waters," J. Afaterialsfor Energy Systems, V. 5, No. 4, March 1984, p. 205. minum brass should have marginal resist- Sato's paper (Figure 5). As shown, the 8. Nagata, K. and S. Sato, "Factors Affecting ance at the inlet end. On the same basis, flow around a partial blockage may reach Corrosion and Fouling of Condenser Tubes of C70600 and C71500 copper nickel alloys almost 8 mps (26.3 fps) when the nominal Copper Alloys and Titanium," Sumitomo would have a 2 to I margin of safety flow is 2 mps (6.6 fps). Debris in the inlet Light Metal Technical Reports, V. 19 Nos. 3 and 4, July 1978, pp. 83-94. against inlet end erosion-corrosion. end increases the shear force several or- 9. Efird, K.D., "The Effect of Fluid Dynamics Despite the apparently ample margin ders of magnitude as compared to the on the Corrosion of Copper Base Alloys in Sea of resistance that C70600 and C71500 values shown in Figure 4, which are for Water," Corrosion, V. 33, No. 1, 1977. passes through or settles out in the tube. ment. Sediment that does not contain or- can develop under sediments containing ganic matter is not likely to be harmful; organic matter and sulfides should oxy- Effect of low elocity the corrosion product film, primarily gen from the water flowing through the LaQue has pointed out that a minimum CuO, is stable and protective under the tube diffuse through the sediment and velocity of about 3 fps is needed to pre- usual range of operating conditions in reach the area where sulfides are being vent free-swimming larvae of biofouling saline, brackish and fresh waters. Sedi- generated. The corrosion rate, now repre- species from settling out and attaching ment that does not contain organic mat- sented by i, is several orders of magni- themselves to the tube wall (Ref. I ). Bu- ter is not likely to lead to under-sediment tude greater than under the normal aerat- low advises "Low velocities may permit corrosion of copper alloys. ed conditions of Point 1. The cathodic the settling out of sea borne debris, mud, Sediment that contains organic matter reaction is again oxygen reduction. silt or suspended solids which, if allowed and goes too long unremoved can lead to Figure I shows steady state conditions. to remain in contact with the metal sur- under-sediment corrosion. Unless this During periods when the environment is face, can result in initiating and perpetu- sediment is removed periodically by shifting from aerated to anaerobic (sul- ating corrosion pitting" (Ref. 2). The au- cleaning, the oxide film will gradually be fide) and the existing film is being re- thor has also suggested a 3-fps minimum replaced by a more porous, less protective placed, corrosion may also be influenced velocity in Table X of the Inco publica- sulfide film. Syrett has shown that al- by galvanic effects. Sulfide films are tion "The Design and Installation of 90- though the sulfide film is protective, oxy- more cathodic than the oxide films. The 10 Copper-Nickel Sea Water Piping Sys- gen, if present with sulfides, accelerates substantial difference in potential be- tems" (Ref. 3). An extensive search of the corrosion of copper alloys (Ref. 4). Since tween the oxide and sulfide films offers literature revealed only a few other casual it is possible for dissolved oxygen in the multiple opportunities for galvanic action references to the need for maintaining flowing water to diffuse through the sedi- to initiate pitting during these film transi- minimum flow rates despite the rather ment, conditions are just right for accel- tion periods. Under-sediment corrosion of well understood adverse consequences of erated corrosion of copper base alloys. copper alloys is characterized by black not doing so. Syrett's potential vs log i diagram can (sulfide) films and pitting. The metal loss Unlike the design velocity, the 3-fps be used to better understand the probable when both oxygen and sulfides are pre- minimum flow rate advocated is the flow sequence of events (Figure 1). Point I sent, point 3 conditions, is all the more rate in any given tube below which sedi- represents normal conditions, an adher- serious when it occurs primarily in pits mentation and/or biofouling increase ent protective Cu2O film is in place. Cor- rather than over the whole surface. rapidly. Should the flow rate in any tube rosion (Cu i>Cu"+ + 2e) is proceeding at drop below 3 fps, the likelihood of sedi- the very low rate characteristic of copper Stainless steel corrosion mentation and/or biofouling is very high alloys in normal waters (i2). The cathodic It is as important to remove sediment and at 1-2 fps is a virtual certainty. Con- reaction is oxygen reduction-the normal from stainless steel tubing as it is from sidering the usual variations in actual reduction reaction. copper alloy tubes. While sulfate reduc- flow rates in individual tubes, this sug- Point 2 represents the steady state con- ing bacteria and sulfides can attack stain- gests that design flow rates of less than 5 ditions with sulfides and no oxygen pre- less steel tubes, the principal concern is fps are quite likely to lead to sedimenta- sent-anaerobic conditions that can de- crevice corrosion. It can and does occur tion, loss of heat transfer capability, un- velop under sediments containing organic under some deposits when sulfides are not der-sediment corrosion and biofouling. matter. Despite the presence of sulfides, present. Oldfield, Sutton, Lee, Kain and Since sediment and under-sediment cor- the corrosion rate (i,) is even lower than others have shown that crevice corrosion rosion can and do occur in fresh and for the normal aerated environment. The can occur in very tight crevices in chlo- brackish waters as well as seawater, mini- cathodic reaction is hydrogen reduction. ride-bearing waters. In the very small mum flow rates need to be maintained in Point 3 represents the conditions that confines of a very tight crevice, oxygen is all cooling waters. Scale deposited from cooling water, I Table 2. Critical shear stress for copper alloys in sea water (Efird) _ and sediment, are mainly responsible for 2 loss of heat transfer capability. When Alloy Critical Shear Stress, dyne/cm that capability must be restored, the con- C12200 - Cu 96 denser or heat exchanger is opened and C68700 - Al Brass 192 cleaned. At low velocities, there is more C70600 - 90-10 Cu Ni 431 sediment deposited and the interval be- C71500 - 70-30 Cu Ni 479 tween cleanings must be shorter. C72200 -85-15 Cr Cu Ni 2969 Heat exchangers are generally not cleaned as regularly as condensers. This may be because, being smaller, they are less critical to plant operation and reduc- 02 Cooling water Hi 02 tion in heat transfer capability is not as serious. Many heat exchangers also seem Hi OH- OH- to be over-designed and can tolerate greater reductions in heat transfer capa- Cathode r Cto bility than most condensers. However, unremoved sediment left long enough can lead to undersediment corrosion of stainless steel and copper alloy tubing. i. Oxidation - Corrosion 2. 02 +2H 20 4e - 4 OH- Copper alloy corrosion M M +e (M* OH-) Reduction Organic matter, if present in sediments, can, through the natural processes of decay, result in sulfides at the sediment Figure 2. Crevice corrosion of stainless steel. The letter Mis the general representation tubing interface. This changes the cnvi- of a metal ion in the uncorroded state. ronment the tube wall sees from aerated 11------~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~I cooling water to anaerobic sulfide sedi- The Nickel The material presented in this publication has been Development prepared for the general Institute is information of the reader an international and should not be used or relied on for specific nonprofit applications without first organization to securing competent advice. serve the needs of The Nickel Development people interested Institute, its members, staff in nickel. and consultants do not represent or warrant its NiDI suitability for any general or specific use and assume no North America liability or responsibility of Nickel Development Institute 15 Toronto Street - Suite 402 any kind in connection with Toronto, Ontario, Canada M5C 2E3 the information herein. Telephone 416362 8850 Telex 06218565 Fax 416362 6346 Europe Nickel Development Institute 42 Weymouth Street London, England W1 N 3L0 Telephone 01 493 7999 Telex 51 261 286 Fax 01493 1555 Nickel Development Institute European Technical Information Centre The Holloway, Alvechurch Birmingham, England B48 7QB Telephone 0527 584 777 Telex 51 337125 Fax 0527 585562 Japan Nickel Development Institute 11-3, 5-chome, Shimbashi Minato-ku, Tokyo, Japan Telephone 034367953 Members of NiDi Telex 72 242 2386 Companhia Niquel Tocantins Fax 034367734 Empresa de Desenvolvimento Central & South America Nickel Development Institute de Recursos Minerais "CODEMIN" S.A. c/o Instituto de Metais Nao Ferrosos Falconbridge Limited Av Nove de Julho, 4015, Caixa Postal 6691 Impala Platinum Limited Sao Paulo-SP, Brasil Telephone 011 887 2033 Inco Limited Telex 38112 5479 MEQ Nickel Pty. Ltd. Fax 011 8858124 Morro do Niquel S.A. India Indian Nickel Development Institute Nippon Yakin Kogyo Co., Ltd. c/o Indian Lead Zinc Information Centre NRNQ (a limited partnership) N 7 Shopping Centre, Block B-6, Satdarjung Enclave New Delhi 110 029, India Outokumpu Oy Telephones 600 973, 604 230 Pacific Metals Co., Ltd. Telex 81 3172050 Sherritt Gordon Mines Limited Australasia Nickel Development Institute Shimura Kako Company, Ltd. P.O. Box 28 Sumitomo Metal Mining Co., Ltd. Blackburn, South Vic 3130, Australia Tokyo Nickel Company Ltd. Telephone 61 38787558 Western Mining Corporation Limited Fax 61 33478525

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J M NiDI NUCLEAR SERVICE WATER PIPING CASE STUDY THE SALEIVI NUCLEAR persed particles of fine sand and clay. The average size of No 15001 GENERATING STATION the particles entering the system is 55 p. Full flow pump 1994 OF THE PUBLIC discharge strainers with a rating of 1/32 inch (0.12 mm) are SERVICE ELECTRIC used to strain and remove debris from the water. Sodium & GAS COIWPANY, hypochlorite is injected into the water using an automatic NEW JERSEY, U-S.A. continuous system to maintain a total residual chlorine level of 0.3 to 0.5 ppm. No other chemicals are added to The Salem Nuclear Generating Station is located in the the water. The water is more brackish during drier periods state of New Jersey on the east coast of the United States of the year, and its temperature varies between 35TF and of America. It has two 1,100 MW operating units which 90TF (20C and 31VC). The pH, chloride, magnesium hard- went into service in 1977 and 1981. Despite regular ness, calcium hardness, and sulfate levels are summarized inspection and maintenance of its service water system, in the table above. The water supply and description have both units began experiencing numerous problems with not changed since the units were first tested. corrosion of the in-plant service water piping. This lead the utility to thoroughly evaluate the problem and possible THE SSTEV replacement materials and to conduct an extensive testing program. The results obtained from both the testing pro- The service water system has two parts, a safety-related gram and the plant's service experience with the various nuclear area which supplies cooling water to reactor plant replacement materials are described in this case study. heat exchangers and a non-safety related turbine area. Both are served by a common intake structure and pumps. The THE WATER SUPPLY majority of the piping is in the safety-related portion of the system, and the two units combined have approximately The Salem plant has an open, once-through service water 100 safety-related heat exchangers. Both unit's service system using Delaware River water which is brackish and water systems were tested approximately 1.5 years prior to has a high silt content. The silt is composed of finely dis- their start-up dates, and stagnant brackish water was present in the piping during that interim period between testing and start-up. The piping for Unit I was installed dur- COOLING WATER AVG. LOW HIGH CHEMISTRY (mg/] (mg/1l (mg/I) ing 1975 and 1976, and the piping for Unit 2 was installed Chloride 3,800 0 10,000 during 1980 and 1981. Corrosion problems have been Magnesium Hardness 796 0 2,000 found throughout the system. The turbine area piping is in (CaCO3 ) Calcium Hardness 220 35 700 continuous use except for shut downs and is primarily large (CaCO3 ) diameter. In the nuclear safety-related system, some por- Sulfate 445 0 1,065 tions are run continuously while redundant safety related pH 7.1 6.2 8.1 sections may contain stagnant water for extended periods of time. The portions of the system which tend to have stagnant water system hydrotests are also conducted. Pumps and important equip- in them for the longest periods of time are the component cooling heat ment are checked for current flows and heat exchangers are moni- exchangers and the pump room coolers which have temperature dri- tored for performance. Daily system walk downs are conducted by ven flow as xvell as the diesel generator coolers where flow is initiat- operations to look for leaks and other potential problems. ed only on infrequent operation of the equipment. Repairs or replacements are scheduled based on the inspection findings and maintenance history. Previously the primary indicators that U~d ergrouuad Pipiaig piping needed to be replaced were through-wall leakage and period- The underground piping is reinforced concrete with a diameter of ic hydro testing. At various times, volumetric non-destructive evaluation (NDE) has also been used to evaluate the condition of the sys- either 24 or 30 inches (609 or 762 mm). When this case study was tem in areas where degradation was observed. In February 1991, a written (1992), the original piping was in place and performing well. program was initiated in one of the units to assess the condition of the Visual inspections and periodic hydrostatic tests indicated that no all the remaining lined carbon steel pipe. Internal visual inspections problems existed and no replacements were necessary. are still used to supplement this testing and are the most widely used inspection method for identifying potential problem areas. IS-Pfrnfu Pipiag The primary in-service inspection programs used by the plant are The original in-plant piping was cement-lined carbon steel in diam- mandated by ASME Section Xl and the plant technical specifica- eters ranging from 34 to 12 inches (20 to 300 mm), coal tar epoxy tions. The only significant change in the program in the last several lined carbon steel with diameters of 16 to 30 inches (410 to 760 years is that inspections have been scheduled more frequently as the mm). The original heat exchanger tubing was 90/10 copper-nickel system aged and more numerous problem areas were identified. This alloy with a diameter of 5/8 inch (16 mm). The primary problem maintenance program has recently been supplemented in accordance experienced with the cement lined carbon steel pipe was that it was with the United States Nuclear Regulatory Commission testing subject to corrosion in areas where there were gaps in the lining requirements mandated by Generic Letter 89-13 which was issued under the welds. The coal tar epoxy lined carbon steel was also sub- July 18, 1989. ject to corrosion in areas where there were gaps in the lining in weld zones or areas of high erosion. More recently, 100% solids epoxy REPLACEMENT MATERIAL coatings have also been used in selected replacement areas. The TESTI NG 90/10 copper-nickel alloy heat exchanger tubes experienced severe pitting corrosion. It was the in-plant piping corrosion problems that The replacement materials currently being used by the utility were lead to the utility's material evaluation, testing, and replacement pro- selected based on a review of the service perfomiance of both the gram. Replacement material selection and performance is discussed original and replacement materials, a technical literature review, a in the "Replacement Material Selection" section. laboratory testing program, and three in-situ material test installations. The cost, availability, and ease of installation were compared VCalv'es CaHId Punmps with the corrosion and erosion resistance provided by each candidate alloy to determine the most cost effective solution. The plant has used nickel aluminum bronze, rubber-lined carbon steel, and CF8 (cast type 316 or UNS J928 10) pump and valve bod- The utility set up three test loops in 1986 to evaluate candidate ies. The CF8 and nickel aluminum bronze valves have been used to replacement materials more extensively. The following materials replace some of the rubber-lined carbon steel and bronze compo- were included in the test loops: various 6 Mo austenitic stainless nents and are reportedly performing "fairly well". There are still a steels [VDNI, Cronifer® 1925 hO (UNS N08925); Allegheny large number of lined carbon steel valves in the system. They are Ludlum Steel Corporation, AL-6XN® (UNS N08367); and Avesta replaced or repaired as necessary. Stainless Inc., 254 SMO® (UNS S31254)] in several product forms and processing conditions; control specimens of Type 316 in various SYSTEM MJAINTEMANCE forms; Alloy 625 (UNS N06625); and Alloy C-276 (UNS N10276). AN D TESTING Both crevice and pitting test specimens were used. The 6% Mo austenitic stainless steels were selected as the primary loop test mate- The utility has a periodic inspection and maintenance program for rial because of the performance of AL-6X heat exchanger tubing and the service water system which has been in place in varying degrees 254 SMO in the replacement applications where they had been used, since initial system start up. System inspection occurs during fuel availability, cost, and ease of fabrication. Although titanium had per- outages, which are approximately 18 months apart. During the formed well in their heat exchangers, the utility would consider using inspection period, various parts of the system are opened and an the material in the future only if field welding could be minimized, internal visual inspection is performed. In those areas where the w hich is typically not practical, and if the price were reasonable. For piping is large enough, crawl-through inspections are conducted. these reasons, titanium was not included in the test loops. At the time The inspections focus primarily on known problem areas. Periodic this case study was prepared, the total exposure time for the various

2 materials ranged from 3 to 4 years. Testing will be on-going. Since epoxy lined carbon steel are being replaced as needed with 6 Mo the test loops are connected to the turbine building service water sys- austenitic stainless steels. The primary indicator that pipe replace- tem and since this section is isolated during refueling outages, there ment is needed is through-wall leakage. Three 6 Mo austenitic stain- have been periods when testing was temporarily interrupted which less steels have been used to date in the plant: 254 SMO®; AL- reduced the total exposure time. 6XN®; and INCO® alloy 25-6M (NS N08925), produced by the INCO family of companies. The total length of 6 Mo austenitic The three test loops, which simulate the various field environments, stainless steel in service at the time of this case study is 7,512 feet contain approximately 80 to 90 specimens each. The service condi- (2,290 meters). The pipe ranges from 3/4 to 20 inches (19 to 508 tions tested are flowing, ambient stagnant, and heated stagnant. The mm) in diameter. For pipe up to and including 2 inches (50.8 mm) test loops themselves were constructed of 6 Mo austenitic stainless in diameter, ANSI Schedules 40S and 80S are used to specify wall steel. The specimens have been in place since 1986, and the results thickness, and, for diameters of 2 inches (50.8 mm) to 14 inches to date have provided the following information. No general, pitting (355.6 mm), ANSI Schedule 40 is used. For larger pipe sizes (16 or crevice attack has been observed on any of the 6 Mo austenitic stainless steel surfaces, weld zones or weld heat-affected zones to inch or greater) schedule standard is used. date. Relatively minor crevice corrosion has been noted on a very small number of 6 Mo austenitic stainless steel crevice specimens after three years in service. Early crevice and pitting attack of the Type 316 was observed, and the samples were removed from the test loops. The number of coupons of Type 316 evaluated was considered insufficient for a strong comparison, so additional Type 316 samples were added in May of 1991 for an improved database. No attack has been noted on the Alloy 625 or the Alloy C-276.

REPLACEMEINT NATERIAL SELECTICON

W;:_ A_'~~~~~. -1a In the early 1980's the initial piping replacements were made with types 304 and 316 stainless steel and carbon steel with polyethylene or 100% solids epoxy linings. Neither the 304 or 316 stainless steels, the polyethelyne lined carbon steel or the 100% solids epoxy lined materials have met long term performance objectives. Containment service water pipe replacement February 7992 Salem Unit 2 The utility began installing small quantities of replacement 6% molybdenum stainless steel materials in 1986. The first large replace- Hope Creek Plant, which is at the same location, went on line in 1987 ment project occurred in late 1988. The replacement materials were and began experiencing problems in the raw water side of its closed selected based on the performance of the initial replacement materials, loop service water system within 2 years of start up. This plant also the test loop results at that time, consultant recommendations, and the has a major on-going replacement program. The 6 Mo austenitic experience of other plants. Either AL-6X® or titanium were used as a stainless steels will be the replacement piping for all currently replacement for the 90/10 copper nickel alloy heat exchanger tubes. planned projects at both plants unless unanticipated problems arise. These replacements were initiated in the early 1980's and both mate- In addition to the piping, all of the fittings, flanges, and other system rials have performed very well. A 20 inch weld mitered elbow of 254 components are fabricated from 6 Mo austenitic stainless steel. SMOG was installed in a very severe service section of in-plant pipe in 1986 and also performed very well. The replacement materials Trsble already placed in service are closely monitored both by visual and Chensil CmPrositioa'u of the NDE in the outages following their installation and there is no indica- Alloys (weight percent) tion of weld or heat affected zone pitting corrosion, which has been a UNS ALLOY Cr Ni Mo C N OTHER significant problem with 304 and 316 stainless steels. NUMBER NAME The 6 Mo austenitic stainless steels were selected as the preferred S31600 Type 316 17 10 2 _ _ S31254 254 SIO 20 18 6 0.75 0.20 - replacement material, because they were judged to be the most cost N08367 AL-6XN 20 24 6 - 0.20 - effective, were readily available, and presented no significant fabri- N08925 25-6NIO and 20 24 6 0.75 0.20 - cation problems. No significant difference in performance has been 1925 hMO N06625 Alloy 625 20 60 9 -- 3 Nb noted among the 6 Mo austenitics during testing or in service. The N10276 Alloy C-276 15 66 15 -- 3W cement and coal tar epoxy lined carbon steel pipe and sections pre- unknown 90/10 copper- 10 90 nickel viously replaced with Type 316 or polyethylene or 100% solids

re3 FABRICATION OF THE 6 preferred replacement material by this utility, because these alloys Alo AUSTENITIC STAfINLESS provided the required corrosion resistance, are considered to be cost STEEL PIPING SSTEM effective, are readily available, and present no significant fabrication problems. Unless unforeseen problems arise, the 6 Mo austenitic Quality fabrication and installation is a requirement for obtaining opti- stainless steels will be used for all of the currently planned replace- mal performance with special alloys, and the utility emphasized this ment programs in both of the Salem Plant units where problems requirement for the replacement work. In most cases, 6 Mo austenitic originally occurred and the Hope Creek Plant where corrosion stainless steels are being welded to each other, but, when the transition problems have also arisen. Since the utility found no significant between the 6 Mo austenitic stainless steel and the pre-existing mater- difference in the performance of the various 6 Mo austenitics, all ial has to be made, electrically insulated flanges are used. Piping of the alloys in the family are considered to be equivalent for use greater than or equal to 3 inches (76 mm) in diameter is shop fabricat- by the utility. Although titanium performed well in service, it is ed prior to installation, whenever possible to ensure optimum control not likely to be considered for future piping installations unless the of all procedures. Smaller diameter piping, which is easier to work price was competitive and field welding could be minimized, with, is fabricated on-site by the installation contractor. Since this was which is often not practical. a new material for the utility and the fabricator, precautions were taken To ensure the success of this on-going replacement program, the to ensure that the workers were adequately prepared. Extensive train- utility and installation contractor conducted an extensive training ing and qualification programs were conducted to ensure that proper and qualification program based on manufacturer recommenda- welding, bending, and cutting techniques were used. NDE of initial tions. Because of these precautions, no significant fabrication welding projects established confidence in the fabricating processes. problems have been encountered. Other utilities and contractors Based on manufacturers' recommendations, the fabricator limits the considering the use of 6Mo austenitic stainless steels are encour- heat input and uses a 9% molybdenum filler of a Alloy 625 chemistry aged to obtain the assistance and recommendations of the materi- (AWS ENiCrMo-3) for all welds. This provides an over alloyed weld al manufacturer as well as other experienced users for best results. metal composition to ensure complete weld metal corrosion resistance. The 6 Mo austenitic stainless steels are readily available in all of Interpass temperatures are kept below 1000C to avoid harmful precip- the common product forms such as fittings, flanges, and other sys- itation in the previous weld passes and heat-affected zone. The utility tem components commonly used in service water systems. This avoids creating crevices whenever possible, because they are a possi- makes it possible to replace all existing components and provide ble site for initiation of corrosion. They have eliminated the use of maximum system cost effectiveness and efficiency. Since there are socket welds for that reason and use full penetration butt welds instead. several 6Mo austenitic stainless steel alloy producers from which The predominant replacement piping is small in size and does not lend to chose, material specifiers can select from a variety of sources itself to inside diameter cleaning. A light flapper wheel is used to based on the properties and components required, quality, techni- smooth the inside diameter when access is possible. System acid pick- cal support, service, delivery, and price. ling is precluded by connections with existing carbon steel piping and the mix of materials for components such as gaskets, valves, and piping, but, in some instances, shop fabricated assemblies are pickled. The Nickel Development Institute would like to acknowledge the assistance of Mr John Rot ey of Public Service Electric & CO NCLUSI ONS Gas Company iho wtas indispensable in this project's success, and PSE&G for its support of this endeavor r Rowley pro- After a significant amount of rigorous testing and collecting actual vided the infornationfor this case study and reviewed thefinal service data, the 6 Mo austenitic stainless steels were selected as the manuscriptfor accuracy.

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10 026 Fabrication and metallurgical experience in 14 035 The influence of risk analysis on the stainless steel process vessels exposed to economics of carbon steel and CRA clad flowlines ...... 28 corrosive aqueous environments ...... 13 14 036 Welding duplex and super-duplex stainless steels ...... 28 10 027 Welding and fabrication in nickel alloys in 14 037 Welding stainless and 9% nickel steel FGD systems ...... 13 cryogenic vessels...... 28 10 031 Repair welding high-alloy furnace tubes ...... 13 14 040 Fabrication techniques for successful 10 039 Stainless steel sheet lining of steel tanks and orbital tube welding ...... 28 pressure vessels ...... 14 14 041 Long life ambition ...... 28 10 061 Development of mechanized field girth welding 14 046 Impact performance of model spot-welded of high-alloy corrosion-resistant pipeline materials ...... 17 stainless steel structures...... 29 10 064 Clad engineering ...... 17 15 001 Nuclear service water piping, 10 068 Specifying stainless steel surface treatments ...... 18 the Salem Nuclear Generating Station ...... 29 10 080 Cleaning stainless steel surfaces prior to 15 002 Nuclear service water piping, sanitary service ...... 19 Oskarshamn Nuclear Power Plant ...... 29 10 085 Microbiologically influenced corrosion of D-0003 Crevice corrosion engineering guide ...... 31 stainless steels by water used for cooling and SR-0005 Occupational exposure limits for nickel and hydrostatic testing ...... 20 nickel compounds ...... 30 11 007 Guidelines for the welded fabrication of nickel-containing stainless steels for corrosion MISCELLANEOUS resistant services...... 21 297 Properties of some metals and alloys ...... I 11 008 Machining nickel alloys ...... 21 11 001 Proceedings of materials engineering workshops ...... 20 11 012 Guidelines for the welded fabrication of 11 011 Proceedings of materials workshops for the nickel alloys for corrosion-resistant service ...... 21 power industry ...... 21 11 019 Stainless steel plumbing ...... 22 12 006 Technical manual for the design and construction of roofs of stainless steel sheet ...... 23 12 011 Design manual for structural stainless steel ...... 23 14 011 Versatility of high-alloyed Ni-Cr-Mo welding DISKETTES consumables ...... 25 D-0001 Stainless steel information and design data 14 016 Fusion boundary cracking in CuNilOFe weldments ...... 26 North American edition ...... 31 14 018 Guidelines for welding dissimilar metals ...... 26 D-0002 Guide to stainless steels - international edition ...... 31 14 019 Resist chlorides, retain strength and ductility D-0003 Crevice corrosion engineering guide ...... 31 with duplex stainless steel alloys ...... 26 14 020 Weld fabrication of a 6% molybdenum alloy to PERIODICALS avoid corrosion in bleach plant service ...... 26 Com m unique 1...... 1 14 028 Lambton's alloy lining ...... 27 Nickel ...... 31 14 029 Fabrication options for nickel-containing alloys in FGD service: guidelines for users ...... 27 VIDEOS 14 032 Recycling a railcar classic ...... 27 V-0001 Stainless steel: the effective solution ...... 31 14 034 Stainless steel reinforcing as corrosion protection . 28 V-0002 Fresh approaches to mold steel selection ...... 31 The Nickel North America Nickel Development Institute Development 214 King Street West - Suite 510 Toronto, Ontario Institute is Canada M5H 3S6 Telephone 1 416 591 7999 an international Fax 1 416591 7987 nonprofit Europe Nickel Development Institute organization 42 Weymouth Street London, England W1 N 3LQ serving the needs of Telephone 44 171 493 7999 people interested Fax 44 171 493 1555 Nickel Development Institute in the application of European Technical Information Centre The Holloway, Alvechurch nickel and Birmingham, England B48 7QB Telephone 44 152 758 4777 nickel-containing Fax 44 152 758 5562 materials. Japan Nickel Development Institute 11-3, 5-chome, Shimbashi Minato-ku, Tokyo, Japan Telephone 81 3 3436 7953 Fax 81 3 3436 7734 Central & South America Nickel Development Institute c/o Instituto de Metais Nao Ferrosos R. Pirapora, 310 Sdo Paulo-SP, Brasil 04008-060 Telephone 55 11 887 2033 Fax 55 11 885 8124 India Nickel Development Institute 55A Uday Park (First Floor) Khel Gaon Marg New Delhi 110 049 India Telephone 91 11 6865631 Fax 91 11 6863376 Australasia Nickel Development Institute Members of NiDI 150 Drummond Street, Suite 3 Codemin S.A. Carlton, Victoria 3053 Australia Companhia Nrquel Tocantins Telephone 613 9650 9547 Falconbridge Limited Fax 613 9650 9548 Inco Limited South Korea Nippon Yakin Kogyo Co., Ltd. Nickel Development Institute Olympia Building, Room 811 Outokumpu Oy 196-7 Jamsilbon-Dong, Songpa-Ku P.T. International Nickel Indonesia Seoul 138 229, South Korea Telephone 82 2 419 6465 Pacific Metals Co., Ltd. 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Printed on recycled paper in Canada Nov 98/6.0 NiDI Nickel Development Institute

Guidelines for the welded farcation of nickel-containing stainless steels for corrosion resistant ser\ces

A Nickel Development Institute Reference Book, Series Ng 11 007 The material presented in this publication has been prepared for the general information of the reader and should not be used or relied on for specific applications without first securing competent advice. The Nickel Development Institute, its members, staff and consultants do not represent or warrant its suitability for any general or specific use and assume no liability or responsibility of any kind in connection with the information herein. NIDI Nickel Development Institute

The Nickel Development Institute is the market development and applications research organization of the primary nickel industry. Incorporated and organized in 1984, its headquarters are in Toronto, Canada. Objective of the Institute is sustained growth in the consumption of nickel. Through a network of small permanent staff and key international consultants and project contractors, the Institute carries out market development activities, market exploration, and applications-oriented technical research relevant to the achievement of its objective around the world. Technical service is provided to nickel consumers and others concerned with nickel, nickel alloys and their uses. Principal marketing efforts of the Institute are directed toward the United States, Western Europe, Japan and the newly industrializing nations in Latin America, the Pacific rim and the Indian subcontinent . .. those countries having the greatest current consumption of nickel and those having the greatest potential for growth. Information services are available to designers, specifiers, and educators as well as to the nickel users. Enquiries are welcomed from architects, engineers, industrial designers, specification writers, and others responsible for selection of materials for manufacturing and construction. The Institute co-operates with colleges and universities by furnishing relevant information and material for engineering, materials science, and industrial design education. Guidelines for the welded fabrication of nickel-containing stainless steels for corrosion resistant services Table of Contents Introduction ...... i

PART I - For the welder ...... 1 Physical properties of austenitic steels ...... 2 Factors affecting corrosion resistance of stainless steel welds ...... 2 Full penetration welds ...... 2 Seal welding crevices ...... 2 Embedded iron ...... 2 Avoid surface oxides from welding ...... 3 Other welding related defects ...... 3 Welding qualifications ...... 3 Welder training ...... 4 Preparation for welding ...... 4 Cutting and joint preparation ...... 5 Weld joint designs ...... 5 Cleaning in preparation for welding ...... 7 Oxides and other surface layers ...... 7 Contamination elements ...... 8 Chlorinated solvents ...... 9 Health hazards ...... 9 Fixturing, fitting and tack welding ...... 9 Fixtures and positioners ...... 10 Backing materials ...... 10 Tack welding ...... 10 Fitting pipe joints for GTAW root welds ...... 11 Purging during pipe root welding ...... 11 Welding Processes ...... 12 Shielded metal arc welding ...... 12 Electrode types .... 133...... : Other guides in SMAW ...... 13 Electrode handling and storage ...... 13 Welding current ...... 15 Arc starting and stopping ...... 15 Gas tungsten arc welding ...... 15 GTAW equipment ...... 16 Consumables ...... 16 Operator technique guides ...... 17 Gas metal arc welding ...... 18 Arc transfer modes...... 18 GMAW equipment ...... 18 Consumables ...... 19 Other welding processes ...... 19 Post-fabrication cleaning ...... : 19 Surface contaminants ...... 20 Detection ...... 20 Removal ...... 20 Embedded iron ...... 20 Detecting embedded iron ...... 21 Removing embedded iron ...... 21 Mechanical damage ...... 22 Safety and welding fumes ...... 22 PART II - For the materials engineer ...... 23 Stainless steel alloys ...... 23 Austenitic stainless steels ...... 23 Effect of welding on corrosion resistance ...... 23 Role of weld metal ferrite ...... 27 M easuring weld metal ferrite ...... 27 Duplex stainless steels ...... 28 Characteristics of duplex stainless steels ...... 30 High temperature exposure ...... 30 Effect of welding on duplex stainless steels ...... 30 Nickel-enriched filler m etal ...... 31 Heat input control ...... 31 Interpass tem perature control ...... 31 Preheat ...... 32 Other stainless steels ...... 32 M artensitic stainless steels ...... 33 Ferritic stainless steels ...... 33 Precipitation hardening stainless steels ...... 34 Corrosion resistant stainless steel castings ...... 34 Heat treatm ent of stainless steel ...... 35 Alternate 1...... 35 Alternate 2 ...... 35 M aterial procurem ent and storage guides ...... 36 Surface finishes ...... 36 Purchasing guidelines ...... 38

PART Ill - For the design engineer ...... 39 Design for corrosion services ...... 39 Tank bottoms ...... 39 Tank bottom outlets ...... 40 Bottom corner welds ...... 40 Attachm ents and structurals ...... 40 Heaters and inlets ...... 42 Pipe welds ...... 42 Appendix A: Specifications for stainless steel for welded fabrication ...... 45 Additional requirements ...... 46 Bibliography ...... 46 Acknowledgement ...... 46 Tables Table 1 - Influence of physical properties on welding austenitic stainless steels com pared to carbon steel ...... 1 Table 2 - Stainless steel cutting m ethods ...... 5 Table 3 - Melting temperatures of metals and metal oxides ...... 7 Table 4 - Suggested filler metals for welding stainless steels ...... 14 Table 5 - Comparison of GMAW arc modes for stainless steels ...... 18 Table 6- Wrought austenitic stainless steels chemical analysis ...... 24 Table 7 - Corrosion resistant stainless steel castings chemical analysis ...... 25 Table 8 - Duplex stainless steels chemical analysis ...... 29 Table 9 - Duplex stainless steel filler metals typical composition ...... 32 Table 10 - Suggested filler metals for welding some of the martensitic, ferritic and precipitation hardening stainless steels ...... 33 Table 11 - Stainless steel products forms ...... 36 Table 12 - Standard mechanical sheet finishes ...... 37 Figures Figures 1-1 to 1-7 - Typical weld joint designs ...... 6 to 7 Figure 2 - Backing bar groove designs ...... 10 Figure 3 - The correct tack weld sequence ...... 11 Figure 4 - Typical pipe purging fixtures ...... 12 Figure 5 - Shielded metal arc welding ...... 12 Figure 6 - Gas tungsten arc welding ...... 15 Figure 7 - Gas metal arc welding ...... 17 Figure 8 - Typical fabrication defects ...... 20 Figure 9 - Crevice corrosion ...... 20 Figure 10 - A scratch serves as an initiation site for corrosion ...... 20 Figure 11 - Effect of carbon control on carbide precipitation in Type 304 ...... 26 Figure 12 - Revised constitution diagram for stainless steel weld metal ...... 28 Figure 13 -Typical microstructure of cold rolled, quench annealed Alloy 2205 seamless tube ...... 28 Figures 14-1 to 14-36 - Designs for improved corrosion service ...... 39 to 44 Introduction

Nickel-containing stainless steels are In the section FOR THE WELDER, it indispensable in the construction of is assumed that the welders or others equipment for the process industries. involved in welded fabrication are These steels are used in place of familiar with the basic techniques used conventional steels for properties such in carbon steel fabrication, but have had as excellent corrosion resistance, limited experience with nickel-containing toughness at low temperatures and stainless steels. The Welder section good elevated-temperature properties. employs a "how to do it" approach for The stainless steels are an excellent the non-engineer but may also serve as choice for chemical, dairy, food, archi- a reference for the welding and metal- tectural, biotechnology equipment and lurgical engineer. similar services. The wrought nickel The section FOR THE MATERIALS stainless steels widely used for corro- ENGINEER describes the various types sion services range from Type 304 of stainless steels, how their metallurgi- (Unified Numbering System, UNS, cal and corrosion characteristics are S30400) through the newer 6% molyb- affected by welding and some of the denum alloys, along with the compara- more specialized aspects of fabrication ble cast alloys and the duplex stainless such as heat treating. Guidelines for steels. material procurement and handling are This publication is presented in three also covered. sections identified as, FOR THE The section FOR THE DESIGN WELDER (page 1), FOR THE MATERI- ENGINEER provides a number of ALS ENGINEER (page 23) and FOR design examples of how the corrosion THE DESIGN ENGINEER (page 39). performance of stainless steels can be enhanced through good design. Part I For the welder

Part I focuses on the fabrication and molybdenum stainless steels. Duplex welding of austenitic stainless steels, stainless steels which are half austenite Types 304, 316, 321 and 347 (UNS and half ferrite are discussed in the S30400, S31600, S321 00 and S34700) section entitled "For the materials and the more highly alloyed 4 and 6% engineer."

Table I Influence of physical properties on welding austenitic stainless steels compared to carbon steel Austenitic stainless Carbon steel steel Remarks Melting point 2550-2650° F 28000F Type 304 requires less heat to produce (Type 304) (1400-14500C) (1540°C) fusion, which means faster welding for the same heat or less heat for the same speed. Magnetic Non-magnetic Magnetic to over Nickel stainless steels are not subject to arc blow. response all temperatures (1) 1300 F (7050C)

Rate of heat Type 304 conducts heat much more slowly conductivity (Type 304) than carbon steel thus promoting sharper (% at 212 0F) (100C) 28% 100% heat gradients. This accelerates warping, (%Oat 1200 0F) (6500C) 66%, 100% especially in combination with higher expansion rates. Slower diffusion of heat expansion through the base metal means that weld zones remain hot longer, one result of which may be longer dwell in the carbide precipitation range unless excess heat is artificially removed by chill bars, etc. Electrical resistance This is of importance in electrical fusion (Annealed) methods. The higher electrical resistance of (Microhm-cm, approx.) Type 304 results in the generation of more heat At 680F (20C) 72.0 12.5 for the same current or the same heat with At 1625 0F (885C) 126.0 125 lower current, as compared with carbon steel. This, together with its low rate of heat conductivity, accounts for the effectiveness of resistance welding methods on Type 304. Thermal Expansion 9.8 6.5 Type 304 expands and contracts at a faster rate over range indicated (68-932°F) (68-11620 F) than carbon steel, which means that increased in./in./F x 10 expansion and contraction must be allowed for in order to control warping and the development of thermal stresses upon cooling. For example, in./in./C x 1 6 17.6 11.7 more tack welds are used for stainless steel (20-5000C) (20-628°C) than for carbon steel.

(1) Duplex stainless steels are magnetic.

1 For the welder Physical properties of Full penetration welds austenitic stainless steels It is well recognized that for optimum strength, butt welds should be full- The physical properties of ordinary penetration welds. In corrosion service, carbon steels and austenitic stainless any crevice resulting from lack of steels are quite different and these call penetration is also a potential site for for some revision of welding proce- crevice corrosion. A typical example of dures. Physical properties, Table I, an undesirable crevice is incomplete include such items as melting point, fusion of a pipe root pass weld such as thermal expansion, thermal conductivity shown in Figure 14-31 (see page 43). and others that are not significantly In some environments, corrosion takes changed by thermal or mechanical place in the crevice which, in turn, can processing. As illustrated in Table I, the lead to early failure of the weld joint. melting point of the austenitic grades is lower, so less heat is required to pro- Seal welding crevices duce fusion. Their electrical resistance Crevices between two stainless steel is higher than that of mild steel so less surfaces such as tray supports tacked to electrical current (lower heat settings) is a tank, as shown in Figure 14-16 (see required for welding. These stainless page 40), also invite crevice corrosion. steels have a lower coefficient of ther- Avoiding such crevices is a design mal conductivity, which causes heat to responsibility and discussed further in concentrate in a small zone adjacent to the section For the Design Engineer, as the weld. The austenitic stainless steels well as calling for corrective action. also have coefficients of thermal expan- However, it is helpful for those actually sion approximately 50% greater than making the equipment to assist in mild steel, which calls for more attention eliminating crevices whenever possible. to the control of warpage and distortion. Embedded iron When new stainless steel equipment Factors affecting develops rust spots, it is nearly always corrosion resistance of the result of embedded free iron. In stainless steel welds some environments, if the iron is not removed, deep attack in the form of Before discussing welding guidelines, it pitting corrosion may take place. In less is useful to describe the types of welds extreme environments, the iron rust and stainless steel surfaces which will may act as a contaminant affecting give the best performance in corrosive product purity, or present an unsightly environments. These are factors that rusty appearance to a surface that the welders or others on the shop floor should be clean and bright. control, rather than alloy selection, Free iron is most often embedded in which is usually made by the end user stainless steels during welding or or Materials Engineer. The manufacture forming operations. Some cardinal of corrosion resistant equipment that will fabrication rules to follow in avoiding give superior service should be viewed free iron are: as a joint effort of selecting the correct alloy and then employing the proper El DO NOT bring iron or steel surfaces welding and fabrication practices. Both into intimate contact with stainless elements are essential. steel. The contact could come from lifting tools, steel tables or storage racks, to name a few.

2 For the welder LI DO NOT use tools such as abrasive When, after normal precautions are disks or wheels that have been previ- taken and there are still surface oxides, ously used on ordinary iron or steel and they can be removed by acid pickling, could have iron embedded. glass-bead blasting or one of the other methods discussed in Post-Fabrication LI Use only stainless steel wire brushes Cleaning. that have never been used on carbon steel. Never use brushes with carbon Other welding related defects steel wire. Three other welding related defects and their removal procedure are listed L1 DO NOT leave stainless steel sheets below. or plates on the floor exposed to traffic. Sheet and plate are best stored in the L1 Arc strikes on the parent material vertical position. damage stainless steel's protective film and create crevice-like imperfections. l Locate stainless steel fabrication Weld stop points may create pinpoint away from carbon steel fabrication, if at defects in the weld metal. Both imper- all possible, to avoid iron contamination fections should be removed by light from steel grinding, cutting and blasting grinding with clean fine grit abrasive operations. tools.

The detection of free iron and removal l Weld spatter creates a tiny weld methods are discussed under Post- where the molten slug of metal touches Fabrication Cleaning in this section. and adheres to the surface. The protective film is penetrated and tiny cervices Avoid surface oxides from are created where the film is weakened welding the most. Weld spatter can easily be For best corrosion resistance, the eliminated by applying a commercial stainless steel surface should be free of spatter-prevention paste to either side of surface oxides. The oxides may be in the the joint to be welded. The paste and form of heat tint resulting from welding on spatter are washed off during cleanup. the reverse side or heat tint on the weld or in the heat affected zone, HAZ. Oxides LI Slag on some coated electrode welds can also develop on the root inside is difficult to remove completely. Small diameter, ID, surface of pipe welds made slag particles resist cleaning and with an inadequate inert gas purge. particularly remain where there is a The oxides may vary from thin, straw slight undercut or other irregularity. coloured, a purple colour to a black Slag particles create crevices and must heavy oxide. The darker the colour and be removed by wire brushing, light heavier the oxide, the more likely pitting grinding or abrasive blasting with iron corrosion will develop, causing serious free materials. attack to the underlying metal. It should be understood that the oxides are Welding qualifications harmful in corrosive environments. Oxides normally need not be removed It is standard practice for fabricators of when the stainless steel will operate at process equipment to develop and high temperatures where oxides would maintain welding procedure specifica- normally form. Heat tint seldom leads to tions, WPS, for the various types of corrosion in atmospheric or other mild welding performed. The individual environments but is frequently removed welders and welding operators are for cosmetic purposes. tested and certified by satisfactorily

3 For the welder making acceptable performance qualifi- P-Number Base metal cation weldments. There are a number of Society or Industry codes that govern 8 Austenitic stainless steels in welding qualifications, but the two most Table VI from Type 304 widely used in the US for corrosion through 347 and Alloy 254 resistance equipment are: SMO plus the similar CF cast - American Society of Mechanical alloys of Table VII Engineers, ASME, Boiler and Pres- 1OH Duplexstainless steels includ- sure Vessel Code - Section IX, ing Alloys 255 and 2205 and Welding and Brazing Qualification; cast CD 4MCu - American Welding Society, AWS, 45 Alloys 904L and 20Cb-3 and Standard for Welding Procedure and 6% molybdenum alloys of Ta- Performance Qualification - AWS ble VI except Alloy 254 SMO. B2.1. Not all alloys have been assigned a Internationally, each country typically P-Number. Alloys without a number has its own individual codes or stand- require individual qualification even ards. Fortunately, there is a trend though similar in composition to an alloy toward the acceptance and interchange already qualified. If an alloy is not listed of specifications in the interest of elimi- in the P-Number tables, the alloy manu- nating unmerited requalification. facturer should be contacted to deter- Common to these codes is the identifi- mine if a number has been recently cation of essential variables that estab- assigned by the code. lish when a new procedure qualification test weldment is required. Essential Welder training variables differ for each welding process but common examples might be: In complying with welding qualification - change in base metal being welded specifications such as ASME and AWS, (P-Number); welders must pass a performance test. A - change in filler metal (F-Number); welder training program is not only - significant change in thickness being essential prior to taking the performance welded; test but also insures quality production - change in shielding gas used; welding. Stainless steels are sufficiently - change in welding process used. different in welding characteristics from ordinary steels that the welders should ASME Section IX classification of be provided training and practice time. P-Numbers often first determines if a Once they are familiar with the stainless separate WPS is needed. A change in a steels, many welders develop a prefer- base metal from one P-Number to ence over regular steels. In addition to another P-Number requires the particular base metal and welding requalification. Also joints made be- process, training should also cover the tween two base metals of different shapes to be welded such as pipe and P-Numbers require a separate WPS, thin sheets or unusual welding positions. even though qualification tests have been made for each of the two base Preparation for welding metals welded to themselves. P-Num- bers are shown below: Stainless steels should be handled with somewhat greater care than carbon steels in cutting and fitting. The care taken in preparation for welding is time

4 For the welder well spent in improved weld quality and a costs. Butt welds should be full penetra- finished product that will give optimum tion welds for corrosive services. Fillet serviceability. welds need not be full penetration as long as both sides and ends are welded Cutting and joint preparation to seal off voids that could collect liquid With the exception of oxyacetylene and allow crevice corrosion. cutting, stainless steels can be cut by the Fillet welding branch connections on same methods used for carbon steel. pipe headers leaves a large and severe Oxyacetylene cutting stainless steel crevice on the ID. This practice invites (without iron rich powder additions) crevice and microbiologically influenced results in the formation of refractory corrosion and should be prohibited for chromium oxides, preventing accurate, stainless steel pipe fabrications in all smooth cuts. The thickness and shape of services. the parts being cut or prepared for weld- The molten stainless steel weld metal ing largely dictates which of the methods is somewhat less fluid than carbon steel shown in Table is most appropriate. and depth of weld penetration is not as great. To compensate, stainless steel Weld joint designs weld joints may have a wider bevel, The weld joint designs used for thinner land and a wider root gap. The stainless steels are similar to those welding process also influences opti- used for ordinary steels. The weld joint mum joint design. For example, spray design selected must produce welds of arc, gas metal arc welding, GMAW, suitable strength and service perform- gives much deeper penetration than ance while still allowing low welding short circuiting GMAW, so thicker lands are used with the former process.

Table 11 Stainless steel cutting methods Method Thickness cut Comments Shearing Sheet/strip, thin plate Prepare edge exposed to environment to remove tear crevices. Sawing & abrasive cutting Wide range of thicknesses Remove lubricant or cutting liquid before welding or heat treating. Machining Wide range shapes Remove lubricant or cutting liquid before welding or heat treating. Plasma arc cutting (PAC) Wide range of thicknesses Grind cut surfaces to clean metal.

Powder metal cutting with Wide range of thicknesses Cut less accurate than iron-rich powder PAC, must remove all dross.

Carbon arc cutting Used for gouging backside Grind cut surfaces to clean metal. of welds and cutting irregular shapes.

5 For the welder Typical joint designs for sheet and Ck plate welding are shown in Figures 1-1 through 1-5. Typical pipe joint designs for gas tungsten arc welding, GTAW, root welds with and without consumable inserts, are shown in Figures 1-6 and 1-7. Consumable insert rings are widely used and are recommended for consistent root penetration. t = .5 in. (12.7 mm) or greater Gap A = .03 in. min. .093 in. (0.8 mm - 2.4 mm) Land B = .062 to .093 in. (1.6 - 2.4 mm) Angle C = 60 to 800 Figure 1-3 Typical double "V" joint for plate. t I'

R Maximum t = .125 in. (3.2 mm) Gap A = .03 in. min., .093 in. max. (0.8 - 2.3 mm) A | I _1 Figure 1-1 Typical square butt joint for sheet. t = .75 in. (19 mm) and over Gap A = .062 in. min. .125 in. max. (1.6 - 3.2 mm) Land B = .062 to .093 in. (1.6 - 2.4 mm) Radius R = .25 in. min. (6.4 mm) lii•1C Figure 1-4 Typical single "U" joint for plate. t 11 HA - B Ma;Kimum t = .5 in. (12.7 mm) Gap A = .03 in. min. .093 in. max. (0.8 mm - 2.4 mm) -- I*1 A Land B = .062 to .093 in. (1.6 - 2.4 mm) t = .75 in. (19 mm) and over Anqle C = 60 to 800 Gap A = .062 in. min. .125 in. (1.6 - 3.2 mm) Land B = .062 to .093 in. Figure 1-2 Typical single "V" joint for (1.6 - 2.4 mm) sheet and plate. Radius R = .25 in. min. (6.4 mm)

Figure 1-5 Typical double "U"joint for plate.

6 For the welder A

t Misalignement .062 in. .062+± .03in. (1.6 mm) Max. D (1.6 ± 0.8mm) A= 37.50 ± 2.50 C= .062 in. .03 in. D< Diameter of filler metal for keyhole (1.8mm 0.9 mm) method D > Diameter of filler metal for continuous Figure 1-6 Typical joint design for pipe feeding method with consumable insert. Figure 1-7 Typical joint design for pipe welded without consumable insert.

Cleaning in preparation for thermal cutting. Stainless steel oxides are comprised mainly of those of chro- welding mium and nickel. Because these oxides The weld area to be cleaned includes melt at a much higher temperature than the joint edges and two or three inches of the weld metal, they are not fused adjacent surfaces. Improper cleaning can during welding. Often an oxide film cause weld defects such as cracks, por- becomes trapped in the solidifying weld osity or lack of fusion. The corrosion resis- resulting in a defect that is difficult to tance of the weld and HAZ can be sub- detect by radiography. This is a basic stantially reduced if foreign material is left difference from welding steel. With steel, on the surface before welding or a heating iron oxides melt at about the same operation. After cleaning, joints should be temperature as the weld metal. While it covered unless welding will be immedi- is considered poor practice to weld over ately performed. a heavy steel mill scale, it does not present the problem caused by a stain- Oxide and other surface layers - less steel oxide film. The differences The joints to be welded should be free of between metal and metal oxide melting the surface oxides frequently left after temperatures is shown in Table l11.

Table IlIl Melting temperatures of metals and metal oxides Metal Melting temperatures Metal Melting temperatures 0F (C) oxide TF (C)

Iron 2798 (1537) Fe203 2850 (1565)

Fe304 2900 (1593) Nickel 2650 (1454) NiO 3600 (1982)

304 S/S 2550-2650 (1400-1454) Cr203 4110 (2266)

7 For the welder Stainless steel wrought products sulphur, carbon - hydrocarbons such delivered by the mills are normally free as cutting fluids, of objectionable oxides and do not grease, oil, waxes need special treatment prior to welding. and primers Any oxide layer would be thin and not likely the cause of welding problems. sulphur, - marking crayons, Very thin metals, such as strip under phosphorous, paints and tem- 0.010 in. (0.25mm) may need special carbon perature indicating cleaning such as vapour honing since markers even light oxide layers may be trapped in small, fast solidifying welds. lead, zinc, - tools such as Stainless steels that have been in copper hammers (lead), service often require special pre-weld hold down or cleanup. If the alloy has been exposed backing bars to high temperatures, the surface is (copper), zinc rich often heavily oxidized or may have a paint carburized or sulphurized layer. Such layers must be removed by grinding or shop dirt - any or all of the machining. Wire brushing polishes and above does not remove the tightly adhering oxides. Stainless steel equipment that The presence of sulphur, phosphorous has been in chemical service may be and low-melting metals may cause contaminated by the product media. A cracks in the weld or HAZ. Carbon or good example is caustic. If caustic is carbonaceous materials left on the left on the surface during welding, the surface during welding may be taken in weld and HAZ often develops cracks. solution, resulting in a high carbon layer Neutralizing caustic residue with an which in turn lowers the corrosion acid solution is part of an effective resistance in certain environments. cleanup prior to welding. It is good Cleaning to remove the above con- practice to give a neutralizing treatment taminants should be accomplished by prior to repair welding chemical equip- following a few guidelines, along with ment. That is, neutralize acid contami- common sense. Metallic contaminants nated surfaces with a mild basic solu- and materials not having an oil or tion and an alkaline contaminated grease base are often best removed by surface with a mild acidic solution. A mechanical means such as abrasive hot water rinse should always follow the blasting or grinding. It is essential that neutralizing treatment. the blasting material or abrasive disk be free of contaminants such as free iron. A Contamination elements - There nitric acid treatment, followed by neu- are a number of elements and com- tralization can also effectively remove pounds that must be removed from the some low melting metals without dam- surface prior to welding. If not removed, age to the stainless steel. the heat from welding can cause Oil or grease (hydrocarbon) base cracking, weld defects or reduced contaminants must be removed by corrosion resistance of the weld or solvent cleaning because they are not HAZ. The elements to be avoided and removed by water or acid rinses. Large common sources of the elements are: weldments are usually hand cleaned by wiping with solvent saturated cloths. Other acceptable methods include immersion in, swabbing with or spraying with alkaline, emulsion, solvent or

8 For the welder detergent cleaners or a combination of misapplication, some organizations these; by vapour degreasing; by steam, prohibit the use of any chlorinated with or without a cleaner; or by high- solvent across the board. Non-chlorin- pressure water jetting. American Society ated solvents are preferred for cleaning for Testing and Materials, ASTM, A380, stainless steels and should always be Standard Recommended Practice for used for equipment and crevices. Cleaning and Descaling Stainless Steel Parts, Equipment and Systems, is an Health hazards - The term health excellent guide for fabricators and hazard has been defined as including users. carcinogens, toxic agents, irritants, A typical procedure to remove oil or corrosives, sensitizers and any agent grease includes: that damages the lungs, skin, eyes or - remove excess contaminant by mucous membranes. Each organization wiping with clean cloth; should assure that the solvents used are - swab the weld area (at least 2 not harmful to personnel or equipment. in.(5cm) each side of the weld) with In addition to the toxic effect, considera- an organic solvent such as aliphatic tion must be given to venting of explo- petroleums, chlorinated hydro- sive fumes, safe disposal of spent carbons or blends of the two. (See solutions and other related handling cautionary remarks below.) Use only practices. Compliance with state and clean solvents (uncontaminated with local regulations is obviously a require- acid, alkali, oil or other foreign ment. material) and clean cloths; Solvents used for pre-weld cleaning - remove all solvent by wiping with include, but are not limited to, the clean, dry cloth; following: - check to assure complete cleaning. - non-chlorinated: toluene, methyl - A residue on the drying cloth can ethyl ketone and acetone indicate incomplete cleaning. Where - chlorinated solvent: 1.1.1. Trichloroethane size allows, either the water-break or All must be handled in compliance atomized test are effective checks. with regulator requirements and manufacturers' instructions. Selecting the solvent cleaner involves considerations more than just the ability to remove oil and grease. Two precau- Fixturing, fitting and tack tions are as follows. welding Good alignment of the assembly prior Chlorinated solvents - Many to welding can reduce welding time. It is commercial solvents contain chlorides essential that the mating pieces to be and are effective in cleaning machined joined should be carefully aligned for parts and crevice free components. The good quality welding. When one mem- potential problem with chlorinated ber is considerably thicker than the solvents is that they may remain and other, for example a tank head thicker concentrate in crevices and later initiate than the shell, the head side should be crevice corrosion and stress corrosion machined to a taper of 3:1 or more to cracking, SCC. There have been unnec- reduce stress concentrations. Joints essary and costly SCC failures of with varying root gap require special stainless steel heat exchangers after adjustment by the welding operator and cleaning with chlorinated solvents. may result in burn through or lack of Cleaning of open, bold areas with penetration. When the volume of identi- chlorinated solvents does not present a cal parts is large, use of fixtures is often problem, but rather than risk a economically justified.

9 For the welder Fixtures and positioners - Fixtures most often used for backing bars. are usually designed for each particular Typical backing bar designs for use with assembly and hold the parts together and without a backing gas are shown in throughout the welding operation. When Figure 2. In the normal course of weld- fixtures are attached to positioners, ing, the copper bar chills the weld to there is a further advantage in that solid metal without melting the copper. welding can be done in the most con- The arc should not be misdirected to the venient position. Some advantages of extent that copper is melted and incor- using fixtures are: porated into the stainless steel weld or - better joint match-up; weld cracking can result. It is good - less tacking and welding time; practice to pickle after welding to re- - distortion from welding is minimized; move traces of copper from the surface - finish assembly is made to closer and essential to pickle if solution anneal- tolerance. ing is to follow welding. It is important that fixture surfaces Argon backing gas provides excellent holding the stainless steel parts do not protection to the underneath side of introduce iron contamination. This can be GTAW welds. It helps control penetra- avoided by surfacing the fixture contact- tion and maintain a bright, clean under ing surfaces with stainless steel and surface. Nitrogen is also used as a using the fixtures only for stainless steel. backing gas and has a price advantage over argon. However, nitrogen should Backing materials - A backing not be introduced into the arc atmos- material should be used in welding phere which, in turn, could alter the weld sheet or plate, unless both sides of the metal composition balance. joint can be welded. Without a backing, When a copper backing bar or an inert the underneath side may have erratic gas backing purge is impractical, there penetration with crevices, voids and are commercially available tapes, pastes excessive oxidation. Such defects and ceramic backing products. These reduce weld strength and can initiate offer some protection from burn-through accelerated corrosion. Copper, with its but give little protection from oxidation, high thermal conductivity, is the material so final cleaning by abrasive means or acid pickling is needed after welding 3 in. approx, typ when these backing materials are used.

Tack welding - Joints not held in fixtures must be tack welded to maintain a uniform gap and alignment along the entire length. The tacks should be placed in a sequence to minimize the effect of shrinkage. In fitting two sheets, 0.015 to 0.035 .187 to .25 tack welds should be placed at each 4, Ad .187 to .25 end and then the middle section as t .062 - shown in Figure 3 (A). Figure 3 (B) diameter I < i shows how the sheets close up when .312 to .375 _ tack welding progresses from one end. diameter Tack welds in stainless steel must be Section A-A Section B-B spaced considerably closer than would Figure 2 Backing bar groove designs. be needed for ordinary carbon steel (A) Standard groove for use without a since the higher thermal expansion of backing gas. (B) Square-corner groove stainless steel causes greater distortion. employed with backing gas. A rough guide is to use about half the

10 For the welder A to pull the joint closed. To maintain the desired gap, it may be necessary to use spacers and to increase the size and number of tack welds. Spacers are usually short lengths of suitable diameter 6 4 , 7 3 8 5 9 2 clean stainless steel wire. Any cracked or defective tack welds should be ground out. Both ends of the tacks on open root welds should be tapered to aid in fusing B into the root weld. The need to maintain a proper gap during root pass welding is two-fold. First, a consistent and uniform gap aids the welder in producing the optimum ID root 1 2 3 4 5 contour. When the joint closes up, there is a tendency for concave roots rather than the desired slightly convex contour. The other reason for a uniform root gap is the Figure 3 The correct tack weld se- need to maintain the optimum root pass quence is shown in A above. When tack chemical composition. For many corro- welding from one end only, as shown in sion services, the filler metal addition is B, the edges close up. essential to provide a weld with corrosion resistance comparable to the base metal. spacing between stainless tacks as used As the joint closes, it is usually impossible for carbon steel when distortion is a to melt a proper amount of filler metal into factor. the weld root. For example, the 6% The length of tack welds may be as molybdenum stainless steels require short as 0.125 in. (3 mm), or a small spot proper root gap and adequate filler metal of weld metal for thin material to over 1 in. addition for high integrity.root welds. (254 mm) long for heavy plate sections. More important, the shape of the tack Purging during pipe root welding - should not cause a defect in the final The pipe interior must be purged with an weld. Heavy or high tacks or abrupt inert gas prior to the GTAW root pass. starts and stops should be contour Failure to use a purge can result in a ground. Bead shape is easier controlled heavily oxidized ID root surface with with the GTAW process, making it a substantially lower corrosion resistance. good choice for tack welding. Tack welds Purging is usually with pure argon, but to be incorporated into the final weld nitrogen is sometimes used because of must be wire brushed or ground to clean lower cost. With duplex stainless steels, metal. They should be inspected for nitrogen backing gas compensates for crater cracks and any cracks ground out. nitrogen lost in the weld metal and restores weld pitting resistance. In Europe, Fitting pipe joints for GTAW root a nitrogen-1 0% hydrogen mixture is welds - Tack welding is important widely used for purging austenitic steel because the tack normally becomes a pipe, but would not generally be accept- part of the root weld. Inert gas purging able for duplex steels. prior to tacking is needed for protection Purging is a two-step operation, the first against oxidation. In tacking joints being done prior to welding to displace air without consumable inserts, or open root inside the pipe. To save time and purging welds as they often are called, there is a gas, baffles on either side of the weld joint strong tendency for the shrinkage forces are often used to reduce the purge area.

1 1 For the welder GMAW processes. The areas covered in Aprox. 6 in. (150 mm) Hinges earlier sections of this publication such HH Weld as base metal properties, joint designs and preparation for welding are common to all welding procedures and are not repeated. Retrieval Hinged Retrieval cord disks cord Shielded metal arc welding Hinged collapsible purging disk SMAW is a versatile process, widely used for welding stainless steel when the shapes or quantity do not justify Vent Chain or linkage Pull cord automatic welding. The electrode is a solid wire covered by an extruded flux coating, although some manufacturers use a cored wire in lieu of the solid core wire. SMAW is frequently referred to as covered electrode or stick welding. The arc zone in the SMAW process is shown Figure 4 Typical pipe purging fixtures. in Figure 5.

Open root weld joints should be taped Molten weld metal and dead air spaces vented prior to Protective gas I coating purging. The internal oxygen content from electrode Electrode wire coating '~~~&Ac should be reduced to below 1% prior to Slag -C7/t>Lr Metal welding. Typical purging fixtures are 3 > ,,/ Dro~~dplets shown in Figure 4. Before the start of welding, the purge Sol ifi e d \\\t flow rate should be reduced to the point weld metal where there is only a slight positive Power supply pressure. Tape covering weld joints should be removed just in advance of the area to be welded. After the root pass, the internal purge should be maintained during the next two filler passes in order to minimize heat tint Figure 5 Shielded metal arc welding. (oxidation) on the inside weld surface. This is especially important when it is The welding is performed manually impractical to pickle after welding. with the welder maintaining control over For those needing more information the arc length and directing the arc into on GTAW root pass pipe welding, there the weld joint. The electrode coating are a number of technical articles and has these functions: specifications available. Two excellent - the outer flux does not burn off as sources are the American Welding fast as the electrode core which, in Society publications listed in the Gen- turn, helps control the arc action and eral References. ability to weld out-of-position; - the flux is used to provide alloy Welding processes addition to the weld metal. The core wire is not always the same composi- This section provides information to tion as the deposited weld metal and assist in formulating stainless steel therefore it is poor practice to remove welding procedures for the shielded the flux and use the core wire for filler metal arc welding, SMAW, GTAW and with another process such as GTAW;

12 For the welder - the gaseous envelope from flux ing current. They are more popular than decomposition excludes oxygen and the lime type because of better operat- nitrogen from the molten weld metal; ing characteristics. The arc is stable and - the molten slag formed on top of the smooth with a fine metal transfer. The weld protects the weld metal from weld bead is uniform with a flat to contamination by the atmosphere slightly concave contour. Slag is easily and helps to shape the bead. removed without a secondary film remaining on the weld bead. Electrode types - The electrodes are selected first on the basis of weld metal Other guides in SMAW - Factors composition and then according to the which contribute to high quality stainless type of coating. Normally, they are of steel welds include proper handling and matching or higher alloy composition to storage of electrodes, correct welding the base metal. In some cases, it is an current along with good arc starting and engineering decision to use a special stopping techniques. composition electrode. The electrode coating type is usually left to the indi- Electrode handling and storage - vidual fabricators. Electrodes for stain- Stainless steel electrodes are normally less steel base metals are shown in furnished in packages suitable for long Table IV. storage. After the package is opened, The flux formula is usually each the electrodes should be stored in manufacturer's jealously guarded heated cabinets at the temperature proprietary information. The flux coating recommended by the manufacturer. If influences how the electrode operates in the electrodes have been over exposed various positions, shape and uniformity to moisture, they should be recondi- of weld bead and that hard-to-define tioned by a higher temperature bake operator appeal. There are two basic using the manufacturer's suggested classifications, namely -15 (lime) and - time and temperature. It is preferable to 16 (basic-titania). For example, an obtain the manufacturer's specific electrode may be either type 308-15 or recommendations, since the tempera- 308-16. Electrode manufacturers often ture often varies with the particular establish their own suffix to designate coating, but lacking this information, special electrodes but AWS A 5.4 - 81 commonly used temperatures are: recognizes only -15 and -16. - storage of opened electrodes Lime coated electrodes (-15) are also 2250F (11 C); known as lime-fluorspar or basic type. - recondition bake They are used on direct current, elec- 5000F (2600C). trode positive, DCEP, (reverse polarity) current, but some brands operate on Moisture in the coating is a concern alternating current, AC. Lime coated because the hydrogen gas generated electrodes give the cleanest weld metal, can cause weld porosity. The pores may lowest in nitrogen, oxygen and inclu- be in the weld metal or may reach the sions. The weld metal tends to be surface just as the metal solidifies, tougher, more ductile, more crack resist- forming visible surface pores. The ant and have the best corrosion resist- porosity can occur in butt welds when ance. The electrodes have good pen- the moisture content of the coating is etration and all-position weldability, high, but more often occurs in fillet which is desirable for field work. welds. Excessive moisture in duplex AC-DC coated electrodes (-16) covered electrodes has the added risk generally have a mixture of lime and of causing hydrogen embrittlement in titania and are often used with alternat-

13 Table IV Suggested filler metals for welding stainless steels

Bare welding Bare welding Covered welding electrodes and Covered welding electrodes and electrode rods - AWS electrode rods - AWS Base AWS or common or common Base AWS or common or common metal name name metal name name AISI AWSA 5.4 AWSA5.9 AISI AWSA5.4 AWSA5.9 (UNS) (UNS) (UNS) (UNS) (UNS) (UNS) 304 E 308() ER 308(1) 20 MO-6(2) (3) (3) (S30400) (W3081 0) (S30880) (N08026) 304L E308L ER 308L 2OCb-3(2) E32OLR ER 32OLR (S30403) (W30813) (S30883) (N08020) (W88022) (N08022) 309 E 309l) ER 309() (S30900) (W3091 0) (S30980) Castings 310 E310 ER 310 ACI type AWSA 5.4 AWSA5.9 (S31 000) (W31010) (S31080) (UNS) (UNS) (UNS) 316 E 316(1) ER 316(') CF-8 E 308() ER 308(1) (S31600) (W31610) (S31680) (J92600) (W3081 0) (S30880) 316L E316L ER 316L CF-3 E 308L ER 308L (S31603) (W31613) (S31683) (J92500) (W30813) (S30883) 317 E317P') ER 317(1) CF-8M E 316(') ER 316(1) (S31700) (W31710) (S31780) (J92900) (W31610) (S31680) 317L E317L ER 317L CF-3M E316L ER 316L (S31703) (W31713) (S31783) (J92800) (W31613) (S31683) 317 LM (3) (3) CN-7M E320 LR ER 320 LR (S31725) (J95150) (W88022) (N08022) 321 E347 ER 321 CK-3MCu (3) (3) (S321 00) (W3471 0) (S52180) (S32154) 347 E 347 ER 347 CA-6NM E410 NiMo ER 410 NiMo (S34700) (W3471 0) (S34780) (J91540) (W41016) (S41086)

Alloy 904L (3) (3) Notes: (N08904) (1)The "L"or low carbon grade or a stabilized grade is always used for welded fabrication except in a few instances Alloy 254 SMOM2) (3) where the slighty higher strength of the regular grades is (3) more important than best corrosion resistance. (S31254) (2)Trade name. 2 (3)A filler metal with 9%or more molybdenum such as the two listed AL-6XN( ) (3) (3) below is normally used to weld these stainless steels. (N08367) Bare welding 1925 hMo 2 ) (3) Covered electrode electrodes and rods (3) AWS A5.11 AWS 5.14 (N08926) (UNS) (UNS) 25-6 MoM2' (3) (3) ENiCrMo-3 ER NiCrMo-3 (N08926) (W86112) (N06625) ENiCrMo-4 Er NiCrMo-4 (W80276) (N1 0276)

14 For the welder the ferrite phase which is not a concern - Avoid excessive weaving of the with the 300-series austenitic stainless electrode. Acceptable weave limits steels. Wet electrodes should not be vary with the particular electrode baked but discarded. and some weave or oscillation is Moisture in the coating is not the only often necessary to obtain accept- cause of weld metal porosity. Welding able bead contour in a lime-type on painted, greasy or oily surfaces may electrode. However, an excessive lead to pores of the worm-hole type. weave results in a high heat input that can cause hot cracking and Welding current - Electrode manufac- increased deformation to the turers usually print on each package the weldment. Weaving is usually recommended current ranges for each limited to 2 to 2.5 times the core diameter. Since stainless steels have a wire diameter. higher electrical resistance than ordinary steels, the current ranges may be 25 to Gas tungsten arc welding 50% of that used for steel electrodes. The GTAW process or TIG, tungsten Excessive current overheats the elec- inert gas, as it is frequently called, is trode coating which in turn causes a widely used and is well suited for weld- loss of arc force and difficulty in directing ing stainless steels. An inert gas (usu- the arc near the end of the electrode. ally argon) is used to protect the molten weld metal and the tungsten electrode Arc starting and stopping - The same from the air. Filler metal in the form of good operator techniques for arc start- bare wire is added as needed, either by ing and stopping used for low hydrogen manual or automatic feeding into the carbon steel electrodes such as type arc. The process is illustrated in Figure E7018, are applicable to stainless steel 6. GTAW can weld material as thin as a welding. few mils to heavy gauges, but usually faster welding processes are used over Some guides are: 0.25 in. (6.4 mm). - Strike the arc at some point in the joint so that the metal is remelted. rkWelding torch An arc strike away from the weld may have cracks and unless re- Tungsten electrode Shielding gas moved, will result in lower corrosion Molten metal weld Arc Filler resistance in that area; Solidified meta etal - Do not abruptly extinguish the arc weld VO leaving a large weld crater. A depression will form as the metal solidifies, often with a slag-filled pipe or cracks in the center of the crater depression. One acceptable technique is to hold the arc over the weld pool for a few moments and then move quickly back, lifting the arc from the completed weld. Another technique is to extinguish the arc against one of the joint side walls after filling the crater;

Figure 6 Gas tungsten arc welding.

15 For the welder Some of the advantages of this specific current ranges while others use process for welding stainless steels a size such as .09 in. (2.4 mm) for a include: much wider current range. Also the - no slag to remove which minimizes electrode end preparation preferences post weld cleanup; vary but one commonly used is a 20 to - an all position welding process which 250 taper with the tip blunted to a 0.010 is particularly useful in pipe welding; in. (0.25 mm) diameter. - no weld spatter to clean; Nozzle or gas cups come in a wide - essentially no alloy loss during variety of shapes and sizes and it is welding. often best to match the nozzle to the weld joint or application. Larger cup GTAW equipment - Direct current, diameters provide better shielding gas electrode negative, DCEN, (straight protection to the weld while smaller polarity) current is standard. One option nozzles help maintain a more stable arc is the pulsed-current where there is a and allow better visibility. An alternate is pulsating high rate of current rise and the gas lens which creates a laminar decay. This current mode is well suited to flow by special screens inside the welding thin material and for joints which nozzle. The flow of inert gas is projected have poor fit-up. Pulsed-current is also a considerable distance beyond the end useful in making the root pass of pipe of the nozzle, giving both better gas joints. A high-frequency starting feature protection and good visibility. is commonly a part of the power source. With any welding process using inert This allows an arc to be initiated without gas, it is important that all gas lines and a scratch start that may result in contami- connections be checked to ensure nation of the tungsten electrode. Some freedom from leaks in the system. If a power sources are provided with a leak is present, for example in a gas feature that allows the electrode to be line, air will aspirate into the inert gas positioned on the work but power does stream rather than the internal gas not flow until the torch is lifted. An advan- exiting as is sometimes believed. tage over high frequency starting is that it eliminates possible interference to Consumables - Pure argon, helium nearby components such as computers. or mixtures of the two are used for In addition to current controls at the shielding gas in welding stainless steels. power source, it is often useful to have a The oxygen bearing argon mixtures used foot pedal current control. This control in GMAW should not be used in GTAW allows the welder to increase or de- because of rapid deterioration of the crease current during welding to adjust to tungsten electrode. Nitrogen additions conditions such as poor fit-up. A further are not recommended for the same advantage is at arc stops where slowly reason. In manual welding and joining reducing the current and in turn the weld thicknesses below .06 in. (1.6 mm), pool, effectively eliminates crater cracks. argon is the preferred shielding gas. It Torches are either air or water cooled. provides good penetration at lower flow The air-cooled variety is limited to lower rates than helium and less chance of currents than the water-cooled. The 2% melt-through. Helium produces a higher thoriated tungsten electrodes are most heat input and deeper penetrating arc commonly used because of their excel- which may be an advantage in some lent emissive qualities, although other automatic welding applications. Argon- tungsten electrode types are acceptable. helium mixtures may improve the bead Opinions differ regarding electrode size contour and wetability. for various amperages. Some favour The correct filler metals for GTAW using a different diameter for a number of stainless steels are shown in Table IV.

16 For the welder Straight lengths are commonly used for concave bead that has a tendency for manual welding and spool or coil wire centerline cracking. Adequate filler metal for automatic welding. Conventional addition produces a slightly convex weld quality control practices to assure clean bead and in some alloys enhances the wire and absence of material mix-up are ferrite evel, both of which improve essential. Bare wire for GTAW should cracking resistance. be wiped clean before using and stored In welds subject to severe corrosive in a covered area. environments, it is often necessary for the welds to be of higher alloy content Operator technique guides - Arc than the base materials being joined to initiation is made easier by devices such give comparable corrosion resistance. as a high frequency start or a pilot arc. In Alloy-enriched welds are possible only the absence of these devices, a scratch when ample filler metal additions are start is used which risks contaminating made. It is difficult to define just how the electrode and the metal being much is ample and to measure it. A welded. Where practical, starting tabs rough guide is that at least 50% of the adjacent to the weld joint are useful in weld metal should be from filler metal eliminating damage to the base metal. addition. However, it is also important The welder must also be careful when that adequate filler metal mixing takes extinguishing the arc. The size of the place before the weld solidifies, other- weld pool must be decreased, otherwise wise segregated spots of high and low crater cracking is likely as the weld alloy may exist. One cause of this type of solidifies. In the absence of a foot pedal segregation is from uneven melting of current control described earlier or a the filler metal along with fast solidifica- power source current decay system, the tion rates. An example of where this type arc pool should be decreased in size by of weld segregation could adversely increasing the travel speed before lifting affect service performance is a root weld the electrode from the joint. Good arc of pipe used in a severe environment. stopping practice is particularly important in the root pass of welds that are welded from only one side, otherwise the cracks Electrode may extend completely through the root Solidified and are difficult to repair. After the arc is weld Shielding broken, the welder should hold the torch metal t~ gas over the crater for several seconds to allow the weld to cool under protection of the argon atmosphere. Stainless steels are easy to weld with the GTAW process. The alloys are relatively insensitive to marginal shielding compared to reactive metals such as titanium or zirconium. However, it is good practice to provide ample shielding protection to both the weld puddle and backside as well as keeping the filler metal within the inert gas envelope during welding. If the process has a potential short- Contactor* Welding coming, it is that the weld may look good control machine but have inadequate filler metal. In some weld joints, this practice can result in a Figure 7 Gas metal arc welding

17 For the welder process are shown in Figure 7. Gas metal arc welding In the GMAW process (often referred Arc transfer modes - The type of to as MIG when an inert shielded gas is metal transfer in GMAW has a profound used or MAG when an active gas is influence on the process characteristics used), an arc is established between a to the extent that it is often misleading consumable, bare wire electrode and to make general statements about the work piece. The arc and deposited GMAW without indicating the arc weld metal are protected from the transfer mode. The three modes most atmosphere by a gas shield, comprised used in welding stainless steels are mainly of the inert gases, argon and/or spray, short circuiting and pulsed arc. helium. Small amounts of active gases Table Vcompares some parameter and such as carbon dioxide, oxygen and usability differences in the three. hydrogen are optional for better wetting and arc action. Some advantages of GMAW equipment - The same GMAW over GTAW and SMAW include: power sources, wire feed mechanisms - faster welding speeds; and torches used for welding ordinary - no slag to remove which minimizes steels are used for stainless steels. post weld clean-up; Plastic liners in the wire feed conduit - ease of automation; and, have been found helpful in reducing - good transfer of elements across drag with stainless wire. The GMAW the arc. process has more welding parameters to control than GTAW and SMAW such The basic components of the GMAW as amperage, voltage, current slope,

Table V Comparison of GMAW arc modes for stainless steels Spray Short circuiting Pulsed arc arc welding type transfer welding Typical thickness 0.125 in. (3mm) min. welded 0.25 in. (6mm) 0.06 in. (1.6 mm) 0.06 in. (1.6 mm) and thicker normal and up and up Welding positions Flat & horizontal all all Relative deposition rate highest lowest intermediate Typical wire 0.06 in. 0.030 or 0.035 in. 0.035 or 0.045 in. diameter (1.16 mm) (0.8 or 0.9 mm) (0.9 or 1.2 mm) Typical welding 250-300 amps 50-225 amps up to 250 amps peak current Shielding gas(l) Argon - 1% 2 90 % Helium 90 % Helium Argon - 2 % 02 7.5 % Argon 7.5 % Argon 2.5% C02 2.5 % CO2 or or 90 % Argon 90 % Argon 7.5 % Helium 7.5 % Helium 2.5 % C02 2.5 % C02 or Argon - 1%02 (1)Other gas mixtures are used, however, the shielding gas should contain at least 97.5 % inert gas, i.e., argon, helium or a mixture of the two.

18 For the welder wire feed, pulse rate and the arc advances in flux cored arc products transfer mode. Consequently the which produce quality welds at higher GMAW power sources are often more efficiency than SMAW. Cored wires are complex and expensive. Some of the often easier to produce to special newer power sources such as the compositions or ferrite ranges than it is synergic pulsed arc have made opera- to melt large heats for solid wire. tion simpler by providing only one Submerged arc welding, SAW, has control dial for the operator, with other been used extensively for welding parameters adjusted automatically. The thickness about 0.25 in. (6.4 mm) and welding current used more than 95% of thicker and for overlay welding. Com- the time is DCEP (reversed polarity). mercial fluxes are available for use with This current gives deeper penetration standard filler metals used for GMAW. than DCEN (straight polarity) and a Plasma arc, electroslag, electron beam, stable arc. DCEN is limited to applica- laser and friction welding are used tions requiring shallow penetration such more and more and the resistance as overlay welding. welding processes; spot, seam, projection and flash welding are readily Consumables - Some of the more adaptable to stainless steels. common shielding gases used in Stainless steel may be joined to itself GMAW are shown in Table V. Spray or a number of other metals by brazing. arc shielding gas is usually argon with It is not usually used when the joint will either 1% or 2% oxygen. Short be exposed to severe corrosive envi- circuiting and pulsed arc welding use a ronments but there are instances in greater variety of shielding gases. A food and other process industries popular mixture in North America is where brazing provides adequate 90% helium, 7.5% argon and 2.5% CO2 properties. but in Europe, helium is quite expen- Oxyfuel welding, OFW, is not recom- sive and 90% argon, 7.5% helium and mended for stainless steels. The 2.5% CO2 is widely used. Whatever the chromium oxide formed on the surface combination, the shielding gas should makes oxyacetylene welding difficult. contain at least 97.5% inert gases However, more important is the ex- (argon, helium or a mixture of the two). treme care needed in welding to avoid Carbon dioxide should not exceed reducing the corrosion resistance of the 2.5% or the weld quality and corrosion weld and weld area. resistance may be reduced. The preferred filler metals to be used Post-fabrication cleaning in GMAW stainless steels are shown in Table IV. The most widely used diam- All too often, it is assumed the fabrica- eters are 0.035 in. 0.045 in. and 0.062 tion, be it a tank, pressure vessel, pipe in. (0.9 mm, 1.2 mm and 1.6 mm) but assembly etc., is ready for service after others are available. the final weld is made and inspected. Post-fabrication cleaning may be as Other welding processes important as any of the fabrication steps Stainless steels can be welded by discussed above. The surface condition most of the commercial welding proc- of stainless steels is critical, both where esses. These processes may offer the product must not be contaminated, advantages not obtainable in SMAW, e.g., pharmaceutical, food and nuclear GTAW and GMAW processes and plants; and where the stainless must should not be overlooked for high resist an aggressive environment such production or special fabrications. As an as in a chemical or other process example, there have been recent industry plant. Surface conditions that

19 For the welder can reduce corrosion resistance may be must be free of organic contaminants grouped into four categories; surface for the acid to be effective in removing contamination, embedded iron, mechani- free iron, surface oxides or similar cal damage or welding related defects. conditions. Because little can be done Figure 8 illustrates some of the common during fabrication to reduce organic conditions. contamination, the fabricator must do this during the final cleanup. Embedded Detection - Visual inspection is ~~~iron or rust usually used for organic contamination, Heat tintx~a~a""

A t _J1

AMMIMMMI 'el

Figure 9 Crevice corrosion occured Figure 10 A deep scratch made during where crayon marks were made and not fabrication served as an initiation site for removed on a stainless steel vessel. corrosion in this vessel.

20 For the welder rust streaks. In addition to being un- trained to administer it in only a few sightly as they corrode, the larger hours. This test is generally required particles of embedded iron may initiate for stainless steel equipment used in, crevice corrosion in the underlying for example, pharmaceutical, food and stainless steel. Figure 10 shows corro- nuclear plants, as well as for equip- sion at several points along a scratch ment used to process chemicals. An where iron had been embedded. In excellent basic guide to these tests is corrosive service, crevice corrosion ASTM A380, "Standard Recom- initiated by large embedded iron parti- mended Practice for Cleaning and cles may lead to corrosion failure that Descaling Stainless Steel Parts." would not otherwise occur. In the pharmaceutical, food, and other Removing embedded iron - processing industries in which stainless Pickling, which is carried out after is used primarily to prevent con- degreasing, is the most effective tamination of the product, embedded method for removing embedded iron. iron cannot be tolerated. In pickling, the surface layer, less than 0.001 in. (0.025 mm), is removed by Detecting embedded iron -The corrosion, normally in a nitric/ simplest test for embedded free iron is hydrofluoric acid bath at 120 0F, to spray the surface with clean water (500C). Pickling not only removes and drain the excess. After 24 hours, embedded iron and other metallic the surface is inspected for rust streaks. contamination, it leaves the surface This is a minimum test that any fabricat- bright and clean, and in its most ing shop can conduct. To ensure resistant condition. Since pickling is against rust-streaked units, the water controlled corrosion, low-carbon or test should be specified in procurement stabilized grades of stainless are documents. preferred. The process may initiate A more sensitive indication of embed- intergranular corrosion in the HAZ of ded iron is obtained by use of the regular unstabilized grades. Because ferroxyl test for free iron. The test pickling is aggressive, it will destroy a solution is prepared by mixing the polished or high-luster surface. following ingredients: Using nitric acid alone will remove superficial iron contamination but few, Ingredient Amount if any, of the larger, deeply embedded % volume or weight particles. Nitric acid treatment is to as passivation. This can Distilled water 94 1,000 cm3 referred Nitric acid, 60-67% 3 30 cm3 be misleading, since the pickled is also passivated when it Potassium ferrocyanide 3 30 g surface contacts air. The solution is best applied using a Small objects are best pickled by one-quart spray applicator, the type that immersion. Piping, field-erected tanks applies bleach to laundry. Iron contami- and vessels too large to immerse can nation is indicated by the appearance of be treated by circulating the pickling a blue colour after a few minutes. The solution through them. Typically, depth of colour roughly indicates the chemical-cleaning contractors are degree of contamination. The solution hired to do this. should be removed after a few minutes When ferroxyl testing shows only with a water spray or a damp cloth. spotty patches of iron, these can be The ferroxyl test is not only sensitive removed by local application of nitric/ but it can be performed in the field as hydrofluoric acid paste. For large easily as in the shop. Personnel can be tanks, filling to about 6 in. (150 mm)

21 For the welder to pickle the bottom, and locally remov- GTAW is usually used because of greater ing embedded iron on side-walls is often ease in making small repair welds. Filler a practical alternative to circulating metal should always be added and wash pickling solution throughout them. passes or cosmetic welds never allowed When pickling is not practical, blasting because of the risk of weld cracking and can be used, but not all abrasives yield reduced corrosion resistance. good results. Glass-bead blasting produces good results but, before blasting, a test should be made to Safety and welding fumes determine that it will remove the surface Safety rules for welding stainless steels contamination. Also, periodic tests are essentially the same as for all metals should be made to see how much reuse as they pertain to areas such as electri- of beads can be tolerated before they cal equipment, gas equipment, eye and begin to recontaminate the surface. face protection, fire protection, labeling Walnut shells have also performed well hazardous materials and similar items. A as an abrasive. good reference guide on welding safety Abrasive blasting with steel shot or is American National Standard Institute/ grit is generally unsatisfactory because Accredited Standards Committee, ANSI/ of the possibility of embedding iron ASC, Z49.1-88, "Safety in Welding and particles. Also, grit blasting leaves a Cutting," published by the American rough profile that makes the stainless Welding Society. steel susceptible to crevice corrosion, Proper ventilation to minimize the whether or not the surface is free of welders' exposure to fumes is important iron. Sand blasting should also be in welding and cutting all metals, includ- avoided if possible, because even new ing stainless steels. In addition to good sand is seldom free of iron particles or ventilation, the welders and cutters other contaminants. should try to avoid breathing the fume plume directly, by positioning the work so Mechanical damage that their head is away from the plume. When the surface has been damaged The composition of welding fumes varies and reconditioning is needed, the repair with the welding filler metal and welding is usually made by grinding or by process. Arc processes also produce welding and grinding. Shallow defects gaseous products such as ozone and are first removed by grinding, preferably oxides of nitrogen. Concern has been with a clean fine grit abrasive disk, a expressed in welding with stainless steel flapper wheel or a pencil type grinder. and high alloy steel consumables be- The maximum grinding depth to remove cause of the chromium and, to a lesser defects is often specified by the fabrica- extent, the nickel usually present in the tion specification and may vary from welding fume. Good ventilation will 10% to 25% of the total thickness. minimize the potential health risk. The When weld repair is needed, it can be International Institute of Welding has made by SMAW, GMAW or GTAW. developed a series of "Fume information sheets for welders" which offer internationally accepted suggested guidelines for fume control.

22 Part 11 For the materials engineer

This section is for the engineer who developed for an austenitic stainless needs further information about the steel to weld a martensitic stainless wrought and cast stainless steel alloys, steel could result in low quality welds. how their corrosion resistance is affected by welding and typical heat treating practices. Also included are Austenitic stainless steels guides for material procurement and Austenitic stainless steels are non- good storage practices. magnetic or only slightly magnetic in the annealed state and can be hardened only by cold working. They possess Stainless steel alloys excellent cryogenic (low temperature) Steel is made corrosion resistant by the properties and good strength at high addition of 11% or more chromium. The temperatures. Corrosion resistance is term stainless describes the non- outstanding in a wide range of environ- rusting, bright appearance of these ments. They exhibit good weldability alloys. The earliest types of stainless and are easy to fabricate provided steel were the straight chromium grades suitable procedures are maintained. with chromium ranging from over 10% The composition of common grades of to about 18%, but through the years a wrought stainless steels and corrosion- number of different type stainless steel resistant stainless steel castings is alloys have been developed and cat- shown in Tables VI and VII. It includes egorized into five groups, namely: alloys commercially available world- - martensitic (AISI* 400-series) wide and those most frequently used for - ferritic (AISI* 400-series) corrosion resistant applications. The - austenitic (AISI* 300-series) UNS numbers in Table VI have either - precipitation hardening an S or N prefix. Stainless steels are - duplex defined by ASTM as having at least *American Iron and Steel Institute 50% iron which UNS identifies with a S number. Alloys with a N number are The austenitic stainless steels are the classified as nickel alloys, but the most widely used but the use of duplex distinction is purely artificial. The alloys is increasing, although they still fabricability of the high alloy S grades represent a small part of the stainless and the nickel alloys in Table VI is steels used. This publication describes essentially the same. these two alloy families and their use. The other three groups, martensitic, ferritic and precipitation hardening are Effect of welding on corrosion also identified as stainless steels but the resistance fabrication and welding is often quite Austenitic stainless steels are usually different from the austenitic and duplex specified for their excellent corrosion grades. When discussing welding and resistance. Welding can reduce base fabrication techniques, the particular metal corrosion resistance in aggressive stainless steel group must be identified, environments. In welding, heat is otherwise serious mistakes could be generated that produces a temperature made. For example, using a procedure gradient in the base metal, i.e. the HAZ.

23 For the materials engineer

Table VI Wrought austenitic stainless steels chemical analysis, %, of major elements (Max. except as noted) AISI Type or common name (UNS) C Cr Ni Mo Other 304 0.08 18.0-20.0 8.0-10.5 0.10N (S30400) 304 L 0.03 18.0-20.0 8.0-12.CI 0.10N (S30403) 309 0.20 22.0-24.0 12.0-15.1I (S30900) 310 0.25 24.0-26.0 19.0-22.1 (S31 000) 316 0.08 16.0-18.0 10.0-14.1 2.0-3.0 0.10N (S31600) 316L 0.03 16.0-18.0 10.0-14.1 2.0-3.0 0.10N (S31603) 317 0.08 18.0-20.0 11.0-15.1 3.0-4.0 0.10N (S31700) I 317L 0.03 18.0-20.0 11.0-15.1 3.0-4.0 0.10N (S31703) I 317 LM 0.03 18.0-20.0 13.0-17.1 4.0-5.0 0.10N (S31725) 321 0.08 17.0-19.0 9.0-12.C 5x%Cmin, (S321 00) 0.70 max. Ti 347 0.08 17-0-19.0 9.0-13.C 10 x %C min, (S34700) 1.10 max. (Nb + Ta) Alloy 904L 0.02 19.0-23.0 23.0-28.1 4.0-5.0 1.0-2.0 Cu (N08904) ) Alloy 254 SMO* 0.02 19.5-20.5 17.5-18.' 6.0-6.5 0.18-0.22N (S31254) 5 0.50-1.00 Cu AL-6XN* 0.03 20.0-22.0 23.5-25.' 6.0-7.0 0.18-0.25N (N08367) 5 0.75 Cu 1925 h Mo* 0.02 20.0-21.0 24.5-25.' 6.0-6.8 0.18-0.20N (N08926) 0.8-1.0 Cu 20 Mo-6* 0.03 22.0-26.0 33.0-37.1 5.0-6.7 2.0-4.0 Cu (N08026) 5 20Cb-3* 0.07 19.0-21.0 32.0-38. 2.0-3.0 3.0-4.0 Cu (N08020) 8x C min, 1.00 %max. 25-6 MO* 0.02 19.0-21.0 24.0-26.( 6.0-7.0 0.15-0.25N (N08926) 0.5-1,5 Cu * 254 SMO is a trademark of Avesta AB AL-6XN is a trademark of Allegheny Lundlum Steel Corporation 1925 hMo is atrademark of VDM Nickel Technologie A.G. 20 Mo-6 and 20 Cb-3 are trademarks of Carpenter Technology Corp. 25-6 MO is a trademark of Inco Alloys International. Inc. 24 For the materials engineer Table VII Corrosion resistant stainless steel castings chemical analysis, %, of major elements (Max. except as noted) ACI Similar Most Type wrought common Anneal at (UNS) type C Cr Ni Mo Others structure OF (0C)

CF-8 304 0.08 18.0-21.0 8.0-11.0 - Ferrite in 1900-2050 (J92600) austenite (1035-1120)

CF-3 304L 0.03 17.0-21.0 8.0-11.0 - 1900-2050 (J92500) (1035-1120)

CF-8M 316 0.08 18.0-21.0 9.0-12.0 2.0-3.0 1900-2050 (J92900) (1035-1120)

CF-3M 316L 0.03 17.0-21.0 9.0-13.0 2.0-3.0 1950-2050 (J92800) (1065-1120)

CN-7M 20Cb-3 (1) 0.07 19.0-22.0 27.5-30.5 2.0-3.0 3.0-4.OCu Austenite 2050 (1120) (N08007) Min.

CK-3M Cu Alloy254SMO(2) 0.02 19.5-20.5 17.5-18.5 6.0-6.5 0.18-0.22N Austenite 2100-2200 (J93254) 0.50-1.00 Cu (1150-1205)

CA-6NM 0.06 11.5-14.0 3.5-4.5 0.4-1.0 - Martensite 1900-1950 (J91540) (1035-1065) followed by double temper CD-7MCuN FERRALIUM (3) 0.04 24.0-27.0 4.5-6.5 2.0-4.0 0.10--0.25N Duplex- 1925 (1050) 255 1.5-22.5 Cu austenite & Min. ferrite CD-3MN ASTM-A- 2205 0.03 21.0-23.5 4.5-6.5 2.5-3.5 0.10-0.30N Duplex- 2050 (1120) 890, Gr4A austenite & Min. (J92205) ferrite

Zeron 100 (4) Zeron 100 (4) 0.03 24.0-26.0 6.0-8.5 3.0-4.0 0.2-0.3N Duplex- 2050 (1120) (J93380) austenite & Min. ferrite (1)20Cb-3 is a tradename of Carpenter Technology Corporation (3)FERRALIUM is a trademark of Langley Alloys, Ltd (2)254SMO is a trademark of Avesta AB (4)Zeron 100 is a trademark of Weir Material Services, Ltd.

Welding may also induce residual attack, IGA, in the weld HAZ. In the stresses in the weld area which in temperature range of about 800°F to certain environments can lead to SCC. 1650°F (4250C to 9000C), carbon Heat treatments to reduce residual combines with chromium to form chro- stresses are discussed in the section mium carbides at the grain boundaries. Heat Treatment of Austenitic Stainless The area adjacent to the carbides is Steels. depleted in chromium. When the car- One of the early corrosion problems bide network is continuous, the low related to welding was intergranular chromium envelope around grains may

25 For the materials engineer

OF 0C

900 , 0.062 16001- 0.080, '

8001 14001-

700 F 12001-

6001- 1000[- 5001- 800 - l I I I I I 10sec. 1 min. 10 min. 1 h. 10 h. 100 h. 1,000 h. 10,000 h.

Time-temperature-sensitization curves

Figure 11 Effect of carbon control on carbide precipitation in Type 304. be selectively attacked, resulting in chromium carbides have formed at the intergranular corrosion. In the worst grain boundaries, when the time at case, the depleted chromium layer is temperature for any particular carbon corroded away and complete grains are content Type 304 is to the right of the % separated from the base metal and can carbon curve. It can be seen that the even fall out. Alloys are said to be temperature where sensitization occurs sensitized when welding or heat treat- most rapidly varies from 13000F ment results in chromium depleted (700 0C), with an alloy of 0.062% car- areas that will be attacked in these bon, to 1 OOF (6000C), for a 0.03% corrosive environments. Sensitized carbon alloy. From Figure 11, an alloy alloys may still provide good service in with 0.062% carbon could become many of the milder environments in sensitized in as little time as 2 to 3 which stainless steels are used. Today, minutes at 1300 0F (700°C ). On the with the trend of mills to furnish lower other hand, 304L with 0.030% carbon carbon products, IGA of austenitic could be held at 11 00 0F (5950C) for 8 stainless steels occurs less often. hours before being sensitized. For this The degree of sensitization, i.e., the reason the low carbon "L" grades are amount of grain boundary chromium most commonly used for corrosion carbides formed, is influenced by the resistant equipment where IGA is a amount of carbon, exposure tempera- possibility. With the "L" grade, the weld ture and time at this temperature. Figure HAZ is not at temperature long enough 11 illustrates the time-temperature- to become sensitized. sensitization curves for Type 304 Grain boundary chromium carbides stainless steel. Curves of other can be prevented from forming when austenitic stainlesses would be similar titanium or niobium-tantalum are but the actual values would be some- present in the alloy. (Niobium,Nb, is what different. To explain Figure 11, the also known by the name columbium, alloy is sensitized, that is a network of Cb, in some references). These ele-

26 For the materials engineer ments have a greater affinity for carbon cooling, the higher the ferrite content. than chromium and form evenly distrib- Unfortunately, ferrite is not obtainable uted carbides away from the grain in all nickel stainless steel alloys. For boundaries, where there is no adverse example, it is not possible to adjust the affect on the corrosion resistance. Type composition to obtain ferrite in Type 310 321 (UNS S32100) contains titanium (UNS S31 000). In spite of being fully and 347 (UNS S34700) contains nio- austenitic and prone to fissures, the bium-tantalum. Both are stabilized alloy has been used over 50 years with versions of type 304. The stabilized excellent service. In the absence of grades are usually preferred where weld metal ferrite, it is more important there will be long time service in the for the filler metal manufacturer to sensitizing temperature range of 8000F control minor elements such as silicon, to 1650° F (4250C to 9000C). phosphorus and sulphur to as low a A third method of preventing IGA in level as possible to prevent cracking. the weld HAZ in alloys containing over When a filler metal is required with a 0.03% carbon is to redissolve the specific ferrite level, the purchaser or chromium carbides by a solution anneal user should specify the level to the at 19000 F to 21500F (10400C to supplier. Stainless steel filler metal 11750C), followed by rapid cooling. specifications, ANSI/AWS A5.4 for The solution anneal is a good method to electrodes and ANSI/AWS A5.9 for bare restore full corrosion resistance when wire do not specify ferrite levels for any the shape, size and geometry of the of the alloy classes. weldment allows the heat treatment. Solution annealing must be closely Measuring weld metal ferrite - controlled in both heating and cooling to While there is wide agreement on the minimize distortion within acceptable beneficial affect of ferrite in the weld, it limits. is not always easy to measure the amount accurately in a given weld Role of weld metal ferrite deposit. One of the three following Microfissures or cracks have been methods can be used. known to occur in austenitic stainless steel welds. They can appear in the 1. Magnetic instruments can measure weld metal during or immediately after ferrite on a relative scale and this is the welding, or they may occur in the HAZ method most used by filler metal proof previously deposited weld metal. The ducers. Calibration of the instruments is microstructure of the weld metal very critical and AWS has developed a strongly influences susceptibility to special calibration procedure. AWS also microfissuring. A fully austenitic weld is details how the weld pad is to be made more prone to microfissuring than a and prepared for testing, since this can weld with some ferrite. influence the measurement. Ferrite Ferrite levels of 5% to 10% or more in determination using sophisticated welds or castings can be quite beneficial laboratory magnetic instruments is often in reducing hot cracking and not practical for the average user. microfissuring. For example, a Type 308 Portable magnetic instruments are (UNS W30840) weld with zero to 2% commercially available that, even ferrite might be quite crack sensitive though they may be less accurate, are while another 308 weld with 5% to 8% easier for the fabricator to use. ferrite would have good crack resistance. The amount of ferrite in a 300-series 2. Using the weld chemical composi- weld is controlled by the composition and tion, ferrite content can be estimated the weld cooling rate, the faster the from a constitution diagram for stainless

27 For the materials engineer

to I1 + cZ ,0OR U? a) I, CZ

0c)

-- I z+ 2 I- -1 - .1- -1'_. -- ~ 16 17 18 19 20 21 22 23 24 25 26 27 Chromium equivalent = %Cr + %Mo + 1.5 x % Si + 0.5 x % Cb

Figure 12 Revised constitution diagram for stainless steel weld metal. (from Metals Handbook, Volume 6, Ninth Edition) steel weld metal, Figure 12. Earlier, temperatures 9000F to 17000F (480CC to ferrite diagrams represented ferrite in 9250C) to avoid a loss of room tempera- units of volume-%. The most recent ture ductility as a result of a high tem- Welding Research Council, WRC, perature sigma phase. Sigma forms diagram determines ferrite number, FN, more readily from ferrite than from by the magnetic response. The FN and austenite and is discussed in the duplex volume-% are the same up to 6% but stainless steel section. differ at higher levels. Ferrite determination using the diagram is easy and quite accurate, provided a reliable chemical Duplex stainless steels anaylsis has been made. Duplex stainless steels are an alloy family that have two phases - ferrite 3. The ferrite content can be estimated and austenite - with ferrite typically by metallographic examination. It is most accurate when ferrite is in the range of 4% to 10% and should be performed by an experienced techni- cian. One advantage to this method is that it can be used on small specimens removed from weldments or where the two other methods are not practical. There are services where ferrite in the weld structure is not a benefit. At cryrogenic temperatures,viz., -320OF (-195oC), toughness and impact strength are reduced by ferrite and it is Figure 13 Typical microstructure of cold common practice to specify welds with rolled, quench annealed Alloy 2205 no more than 2 FN and preferably 0 FN. seamless tube. Dark phase - ferrite, It is also desirable to have low ferrite light phase - austenite. when the welds are exposed to service (from Sandvik AB)

28 For the materials engineer between 40% and 60%.The ferrite/ is improved pitting and crevice corrosion austenite ratio is accomplished in resistance. With proper welding proce- wrought alloys by composition adjust- dures, as-welded second-generation ment along with controlled hot working duplex stainless steels can have nearly and annealing practices at the mill. The the same level of corrosion resistance as alloys could properly be called ferritic- mill annealed material. Nitrogen is also austenitic stainless steels but the term beneficial in the manufacture of second- "duplex" is more widely used. A typical generation alloy plates, where the duplex stainless steel microstructure is ductile-brittle transition is depressed well shown in Figure 13. The matrix which below room temperature, making heavy appears as the darker background is section weldments practical. However, ferrite and the elongated, island-like duplex alloys are generally not used lighter phase is austenite. below about -500F (45oC) Duplex alloys date to the 1930s and whereas some fully austenitic alloys may the early alloys are now identified as be used to -4560 F (270oC). first-generation. Unfortunately, the early Alloy 2205 (UNS S31803) is the most alloys had a problem of significant loss of widely used duplex alloy and is available corrosion resistance in the as-welded from a number of producers. Comparing condition and it has taken some time for the duplex composition to a fully the new second-generation alloys to austenitic stainless steel such as Type overcome this reputation. All the alloys 316, 2205 is higher in chromium, lower shown in Table VII are second-genera- in nickel and contains nitrogen. The tion alloys and typically contain 0.15% to nitrogen addition is very critical in duplex 0.30% nitrogen. One benefit of nitrogen alloys as will be discussed shortly.

Table Vill Duplex stainless steels chemical analysis, %, of major elements (Max. except as noted) Common name

(UNS) C Cr Ni Mo Others

7-Mo PLUS (" 0.03 26.0-29.0 3.5-5.2 1.0-2.5 0.10-0.35N (S32950)

Alloy 2205 0.03 21.0-23.0 4.5-6.5 2.5-3.5 0.08-0.20N (S31803)

FERRALIUM 255(2 0.03 24.0-27.0 4.5-6.5 2.0-4.0 0.10-0.25N (S32550) 1.5-2.5Cu

SAF 2507 ( 0.03 24.0-26.0 6.0-8.0 3.0-5.0 0.24-0.32N (S32750)

Zeron 100 (4 0.03 24.0-26.0 6.0-8.0 3.0-4.0 0.5-1.0 Cu (S32760) 0.5-1.0 W 0.2-0.3 N

(1) 7-Mo PLUS is a trademark of Carpenter Technology Corporation (2) FERRALIUM is a trademark of Langley Alloys, Ltd. (3) SAF 2507 is a trademark of Sandvik AB (4) Zeron 100 is a trademark of Weir Material Services, Ltd.

29 For the materials engineer Characteristics of duplex producing or fabricating the alloys, a high temperature solution anneal at stainless steels 19000F (10400C) or higher, depending The duplex alloys offer two important on the alloy, followed by rapid cooling is advantages over austenitic alloys such employed to give optimum mechanical as 304L and 316L, namely greater properties and corrosion resistance. In resistance to chloride stress corrosion exposure to the temperature range of cracking, CSCC, and higher mechanical 6000F to 17500F (3150C to 950°C) the properties. The yield strength of duplex duplex alloys act differently than the alloys is typically two to three times austenitics but once the differences are higher and the tensile strength 25% recognized, no problems should arise. higher while still maintaining good An intermetallic phase called sigma ductility at normal operating tempera- can form when duplex alloys are held in tures. the 12000F to 17500F (6500C to 9500C) The susceptibility of austenitic stain- temperature range. Sigma causes room less steels to CSCC at temperatures 0 temperature embrittlement and, when above about 140 F (600C) is a well present in appreciable amounts, corro- known concern. The ferritic stainless sion resistance is lowered. However, steels are highly resistant but are more attention to minimum time in the sigma difficult to fabricate and weld. The forming range during annealing and duplex alloys have intermediate resist- welding, improved processing control at ance to CSCC which, in many environ- the steel mill and the beneficial effect of ments, represents a substantial im- nitrogen can essentially eliminate any provement over the austenitics. The sigma problem. In normal second- duplex alloys also offer: generation duplex welding procedures, - general and pitting corrosion resist- the weld or HAZ is not at temperature ance equal to or better than type long enough for sigma to be a factor. 316L stainless steel in many envi- Another high temperature occurrence is ronments; a phenomenon called 8850F (4750C) embrittlement. It can occur when a - resistance to intergranular corrosion duplex alloy (or any iron-chromium alloy due to the low carbon content; containing 13% to 90% Cr) is held within or slowly cooled through the - good resistance to erosion and temperature range of 600°F to 1000°F abrasion; and, (3150C to 5400C). With the second- generation duplex alloy and using - a thermal expansion coefficient standard annealing and welding prac- close to that of carbon steel which tices, the weld or HAZ is not at tempera- can result in lower stresses in ture long enough for this embrittlement weldments involving duplex stainless to occur. It is mentioned here as a and carbon steel. precaution should there be need to deviate from standard procedures. There are metallurgical differences compared to the austenitic alloys that when known and recognized are easily Effect of welding on duplex handled. The differences occur as a stainless steels result of high temperature exposure. The weldability of second-generation duplex alloys has been greatly improved High temperature exposure - through controlled nitrogen additions Duplex stainless steels are normally and the development of nickel-enriched used in the temperature range of about filler metals. Using a few welding -500F to 5000F (-450C to 260CC). In procedure controls, sound welds with

30 For the materials engineer corrosion resistance comparable to the current AWS stainless steel filler metal base metal are obtained. The impor- specifications but will be included in tance of controls on heat input, interpass future editions. temperature, preheat and nickel-enriched filler metal are as follows: Heat input control - There is not complete agreement on the part of Nickel-enriched filler metal - Duplex producers and welding investigators as stainless steel welds made with matching to the proper limits on heat input. The composition filler metal or autogenously argument for high heat input (see welded (no filler metal) may exhibit 80% formula) is that it allows more time for or more ferrite in the fusion zone in the ferrite to transform to austenite, particu- as-welded condition. A weld with such a larly in the heat affected zone. The high ferrite level has poor toughness and concern for high heat input is that it ductility and often will not pass a bend could allow embrittling phases, such as test. The higher ferrite content of such sigma and 8850F (4750C) embrittlement welds also markedly reduces corrosion to develop in the ferrite. With the resistance in many aggresive environ- second-generation duplex stainless ments. An anneal at 19000F to 2100F steels, longer time at temperature is (10400C to 11500C) restores the desired needed for these phases to develop, so ferrite/austenite balance but the treat- there should be no significant ment is not practical for many fabrications embrittlement. A generally accepted and is expensive. Increasing the nickel heat input range in kilo joules (kJ) is 15 content of the filler metal allows more to 65 kJ/in. (0.6 to 2.6 kJ/mm) although austenite to form so that welds in the as- levels as high as 152 kJ/in. (6.0 kJ/mm) welded condition have typically 30% to are claimed to have been successfully 60% ferrite. Welds made with nickel- used. When a welding process with enriched filler metals have good as- less than 15 kJ/in. (0.6 kJ/mm) heat welded ductility, are able to pass bend input must be used, preheating to tests, and have corrosion resistance 2000F-4000F (950C - 205'C) is helpful comparable to the base metal. in reducing the cooling rate and increas- It is desirable that all weld passes be ing austenite in the weld. Where there is made with substantial filler metal addi- a question on heat input for a particular tion to provide a nickel enhanced weld duplex alloy, it is a good practice to metal compostition. A large amount of contact the material supplier for specific base metal dilution can result in welds recommendations. having a high ferrite content with lower Heat input in kJ/in. is calculated: ductility and toughness. An example of where this can occur is the root pass of Voltage x Amperage x 60 a pipe weld with high base metal dilution. Special care should be taken to Travel speed (inch/minute) x 1000 add sufficient nickel-enriched filler metal. Joints with a feather edge and tight fit- Interpass temperature control - An ups favor high dilution and are best early concern was that a high interpass avoided. Joints with an open root temperature could result in 885°F spacing and a land are preferred since (4750C) embrittlement and a limit of they require the addition of filler metal. 300°F (1500C) maximum interpass Nickel-enriched filler metal products temperature was suggested. This limit is for the duplex alloys are available as conservative and in some instances a covered electrodes, bare filler metal and maximum limit of 450°F (2300C) could flux cored wire as shown in Table IX. be acceptable. However, in the interest Duplex filler metals are not covered by of consistency, fabricators often specify

31 For the materials engineer Table IX Duplex stainless steel filler metals typical composition

Filler metal For welding common name base metal (UNS) C Cr Ni Mo Others Covered electrodes 2209-16 "I 2205 0.03 23 9.7 3.0 0.10N (W39209) tentative (S31803)

22.9.3.L-16 12) 3RE60 (S31500) 0.03 22 9.5 3 0.15N 22.9.3.L-1512' 2205 (S31803) 2 22.9.3.LR' , 2304 (S32304) 7-Mo PLUS Enriched Ni'3' 7-MO PLUS 0.03 26.5 9.5 1.5 0.20N (S32950) FERRALIUM 255141 FERRALIUM 255 0.03 25 7.5 3.1 0.20N (W39553) tentative (S32550) 2.0 Cu Bare filler wire 2 22.8.3L' ) 3 RE60 (S31500) 0.01 22.5 8 3 0.10N 2205 (S31803) 2304 (S32304) 7-Mo PLUS Enriched Ni'3' 7-Mo Plus 0.02 26.5 8.5 1.5 0.20N (S32950) FERRALIUM 255'4 FERRALIUM 255 0.03 25 5.8 3.0 0.17N (S39553) Tentative (S32550) Zeron 100 filler wire51 Zeron 100 0.03 25 10* 3.5 0.25N (S32760) 0.7 Cu 0.7W Flux Cored Wire In-Flux 2209-01 2205 0.02 22.0 8.5 3.3 0.14N (W31831) (S31803) In-Flux259-0" FERRALIUM 255 0.02 25 10 3.2 0.14N (S32550) 2.0 Cu

2209-16, In-Flux 2205-0 and In-Flux 259-0 are ,'4 FERRALIUM is a trademark of Langley Alloys, Ltd. trademarks of Teleldyne McKay 5' Zeron 100 is a trademark of Weir Material Services, Ltd. ,2i 22.9.3.L-16, 22.9.3.L-15, 22.9.3.LR and 22.8.3.L are * When the joint is fully heat treated after welding, Ni should trademarks of Sandvik AB be 6.0-8.0% '3) 7-Mo PLUS is a trademark of Carpenter Technology Corporation the same value used for austenitic low heat input welding process, below stainless steel, 300°F or 350°F (150°C to 15 kJ/in. (0.6 kJ/mm), must be used, a 1750C). preheat of 200°F-400°F (95°C-2050C) reduces rapid cooling and decreases Preheat - There is no need for the amount of ferrite in the weld metal preheat on thicknesses 0.25 in. (6 mm) and HAZ. and less on welds made with nickel- enriched filler metals. In heavier sec- Other stainless steels tions and high restraint welds, preheat may be used to advantage in minimizing Other types of stainless steels are the chance of weld cracking. When a martensitic, ferritic and precipitation

32 For the materials engineer three types follows and illustrates some extensively used for heavy components of the basic differences from the such as pump bowls, valve bodies and austenitic alloys. Some of the more compressor cases. CA-15 (UNS J91150) common alloys and their welding filler was the standard alloy but has been metals are shown in Table X largely replaced by CA-6NM (UNS J91540). Compared to CA-15, CA-6NM has improved toughness and weldability, Table X along with better resistance to cavitation. Suggested filler metals for welding It is preferable to weld CA-6NM cast- some of the martensitic, ferritic and ings in the heat treated condition rather precipitation hardening stainless steels than the as-cast. Welding is usually done at room temperature although a preheat of 250°F to 300°F (120 0C to 1500C) may Covered Bare welding be beneficial for large welds in heavy or Base welding electrodes and highly stressed sections. After welding, metal electrode rods the casting is heated to not higher than AISI AWS A5.4 AWS A5.9 11 00°F to 11 50°F (5900C to 6200C) and (UNS) (UNS) (UNS) air-cooled. When there is a special Type 410 (wrought) E4 10 ER410 hardness requirement, CA-6NM may be (S41 000) (W41 010) (W41040) given a normalizing heat treatment above CA-15 (casting) E4 10 ER410 1750°F (9500C) and air cooled, followed (J91540) (W41 010) (W41040) by a double temper of 11 00 0F to 11 50°F CA-6NM (casting) E41ONiMo ER41 ONiMo (590°C to 620°C). The casting should be (J91540) (W41016) (W41046) cooled to room temperature between Type 430 (wrought) E430 ER430 each tempering treatment. (S43000) (W4301 0) (W43040) 17-4PH E630 (') ER630 (1) Ferritic stainless steels (S1 7400) (W3741 0) (W37440) The ferritic alloys are not hardenable

() When weld does not need to match bare metal by heat treatment and only slightly strength, E 308 (UNS W30810) or ER 308 hardenable by cold working. They are (UNS W30840) are often used. magnetic and have good resistance to corrosion in many environments. Most typical of the ferritic stainless steels is Martensitic stainless steels type 430 (UNS S43000), a straight- The martensitic alloys can be hard- chromium alloy with 16% to 18% chro- ened and strengthened by heat treat- mium, 0.12% max. carbon, some minor ment and only slightly hardened by cold elements and the balance iron. working. They are strongly magnetic, Weldability of the ferritic stainless resist corrosion in mild environments and steels is generally better than the have fairly good fabricating qualities. The martensitic. Exposure to high tempera- alloys are often selected because of high tures, such as in the weld heat affected mechanical properties and low cost. zone, causes a reduction in ductility and Weldability of the martensitic toughness along with grain coarsening. stainlesses varies with alloy content, Solution annealing to prevent IGA is particularly the amount of carbon. The done at 14500°F (7900C) for ferritic higher the carbon content, the greater stainless steels instead of 19000F to the need for preheat and postweld heat 1950°F (1040 0C to 1065°C) as for treatment to produce sound welds. austenitic stainless steels. There is While the wrought martensitic stainless greater need for preheating and steels have limited use in process postweld annealing as the thickness and industries, the cast grades have been joint restraint increases.

33 For the materials engineer Precipitation hardening areas worn and corroded in later service stainless steels will sensitize the HAZ to IGA. Users can and should request a 0.03% C maxi- Iron-chromium-nickel alloys contain- mum as an exception to the specifica- ing precipitation-hardening elements such as copper, aluminum and titanium tion in order to prevent IGA in this alloy. Normally, these castings are welded have good weldability, comparable to without problems, but where welding that of the austenitic alloys, but are often is extensive, special techniques used for components which require little may be needed to prevent microfissures next or no welding. When welding is required, to the weld. Techniques available are low it is best to weld these alloys in the interpass temperatures, low heat input annealed condition prior to the final age and peening of the weld to relieve hardening heat treatment. These stain- mechanical stresses. less steels are hardenable by a combina- The austenitic and duplex castings in tion of cold working and a low-tempera- 0 Table VII are usually purchased to one ture heat treatment, 850 F to 11 00F of the following specifications: (4550C to 5950C). ASTM A 743 - Castings, Iron- Corrosion resistant Chromium, Iron-Chromium-Nickel, Nickel-Base, Corrosion Resistant, stainless steel castings For General Application. Stainless steel castings are classified, based on their end use, as corrosion ASTM A 744 - Castings, Iron- resistant or heat resistant, and are Chromium, Nickel-Base, Corrosion designated accordingly by the first letter Resistant, For Severe Service. C or H. The heat resistant grades are generally higher in alloy content than Both specifications require that the the corrosion types and in nearly all casting be solution annealed which cases have higher carbon. The follow- largely removes alloy segregation and ing remarks apply to corrosion resistant dendritic structures occurring in cast- types and may not be applicable to the ings, particularly in heavy sections. The heat resistant alloys. The chemical high temperature anneal of 1900'F composition of the more common (1040'C) or higher, depending on the austenitic and duplex cast alloys is alloy, promotes a more uniform chemi- shown in Table VII (see page 25). cal composition and microstructure, as The most widely used, CF-3, CF-3M, well as dissolving carbides. As a result CF-8 and CF-8M grades, normally have of the anneal, the casting is in the most 5% to 20% ferrite in the austenitic corrosion resistant state. For best matrix. The amount will vary with corrosion resistance, the widely used composition, thermal history of the CF-3M and CF-8M grades must be casting and at different locations in the annealed at 20500 F (1120 0C), not casting. Ferrite is beneficial in minimiz- 19000F (1040'C) as allowed by the ing casting cracks and improving specification. weldability. Some cast corrosion resist- Stainless steel castings are often ant stainless steel grades such as welded, either by fabricators making CN-7M are fully austenitic by nature of assembly welds, during service life or their composition. ASTM Specifications by the foundries weld repairing defects. do not as yet include the 0.03% carbon When the casting will be placed in a grade for CN-7M as they do for the severe corrosive environment, selecting standard grades. Weld repair of cast- a low carbon version such as CF-3 or ings at the foundry or weld buildup of CF-3M can avoid problems resulting

34 For the materials engineer from the formation of chromium car- When weldments are solution annealed bides in the weld HAZ. The same effect and rapidly cooled, new residual of chromium carbides on IGA discussed stresses are often introduced. These in wrought alloys is true for cast alloys. stresses can cause movement after The need for a low carbon version machining, with the result that the part applies not only for the initial fabrication exceeds dimensional tolerance limits. welds but also for later maintenance Stress relieving of mild steel weldments overlay and weld buildup of cast compo- is frequently performed but it is best to nents. When a low carbon grade is not avoid stress relief treatments of stain- included in ASTM A743 or A744, an less steel weldments unless absolutely exception to the specification can necessary. When it is necessary, two usually be reached with the foundry. alternates are available, namely: One difference between A743 and A744 is that A744 requires a full solu- Alternate 1 - Use a low temperature tion anneal after all weld repairs except stress equalizing treatment at 6000 F to for minor repairs as defined in the 8000F (3150C to 4250C) with a hold of 4 specification. Austenitic A743 castings hours per inch of thickness, followed by which are intended for general service a slow cool. Since the alloys have do not require the solution anneal to be excellent creep strength, the low tem- made after all weld repairs. Knowledge perature treatment removes only peak of the intended service conditions is stresses. The treatment is safe to use helpful in selecting the correct material with the standard grades such as 304 specification and casting grade but if and 316 as well as the stabilized and this information is not available, a low low carbon grades since the tempera- carbon grade of W744 is usually a good ture is below that at which harmful choice. chromium carbides form. Heat treatment of Alternate 2 - If the 6000F to 8000F (3150C to 4250C) treatment is inad- stainless steel equate in reducing stresses to the level desired, stress relieving in the range of Austenitic stainless steels, both wrought 0 0 forms and castings, are normally sup- 800 F to 1700 F (4250C to 9250C) may plied in the solution annealed condition. be required. The higher the temperature In solution annealing, the alloy is heated and the longer the time, the more 0 complete the stress relief. For example, to a high temperature, 1900 F to 0 21500F (104000 to 11750C) depending one hour at 1600 F (8700C) removes on the alloy type, and rapidly cooled, about 85% of the residual stresses. usually by a water quench. At the However, the standard grades such as annealing temperature, chromium Types 304 and 316 cannot be heated in carbides are put back into solution as this range without sacrificing corrosion chromium and carbon, restoring the full resistance as a result of carbide precipi- resistance to IGA of the alloy. The tation. A stabilized grade, e.g., 321, 347 anneal also removes the effect of cold or 348 or a low carbon grade, e.g., working and places the alloy in a soft, 304L, 316L etc. should be used when ductile condition, however, the quench- stress relief in this temperature range is ing operation may leave considerable required. Refer to Figure 11, page 26, in residual stresses. developing stress relief treatments that In fabrication, even higher residual will avoid carbide precipitation and IGA stresses may be developed as a result in Type 304. of forming operations and welding.

35 For the materials engineer Table Xl Stainless steel products forms

Diameter Item Description Thickness Width or size Sheet Coils and cut lengths: Mill finishes Nos. 1,2D & 2B under .187 in. 24 in.& over - Pol. finishes Nos. 3, 4,6, 7 & 8 under .187 in. all widths Strip Cold finished, coils or cut lengths under .187 in. under 24 in. - Plates Flat rolled or forged .187 in.& over over 10 in. Bars Hot finished rounds, squares, octagons and hexagons - - .25 in. & over Hot finished flats .125 in.& over .25 in.to 10 in.incl. Cold finished rounds, squares, octagons and hexagons - - over 1.2 in. Cold finished flats - .375 in. & over - Rods Hot rolled rounds, squares, octagons, and hexagons in coils for cold rolling or cold drawing. - - .25 in.to .75 in. Wire Cold finished only: round, square, octagon, hexagon, flat wire 0.010 in.to .062 in.to .5in. & under under .187 in. under .375 in. Extrusions Not considered "standard" shapes, but of wide interest. Currently limited in size to approximately 6.5 inches diameter circle, or structurals to 5 inches diameter. Tubing Dimensions by the outside diameter and wall thickness. Piping Nominal pipe size is the inside diameter from .125 inch to and including 12 inches. Nominal pipe size is the outside diameter for 14 inches and larger diameters. The wall thickness is dimensioned by schedules (5S, 1OS, 20, 30, 40, 80, 120, 160, XX and variations thereof) for all nominal pipe sizes.

Material procurement and are included in weldments, it is useful to storage guides review the extent to which the heat affected zone of welds may suffer GA Table Xl shows the principal stainless in the process fluid of interest. steel wrought product forms - plate, sheet, pipe and tubing - most com- Surface finishes monly used in welded fabrication. These are normally purchased in the low Table XII shows the standard finishes for carbon modification for each grade, sheet and strip. The most widely used although the alloys stabilized with finish for sheet is 2B. Polished finishes titanium or niobium-tantalum are also are also available but are not normally used as discussed in the section on used in welded fabrications for the welding for corrosion resistance. Bars chemical and other process industries and structural shapes are sometimes except food and medical equipment. included in the fabrication. With bars There is no standard surface finish for and shapes, the higher carbon grades plate as there is for sheet and strip. are normally used because of their Plate is normally hot rolled, annealed somewhat higher strength. When they and pickled. Surface defects and

36 For the materials engineer Table XII Standard mechanical sheet finishes

Unpolished or rolled finishes: No. 1 A rough, dull surface which results from hot rolling to the specified thickness followed by annealing and descaling. No. 2D A dull finish which results from cold rolling followed by annealing and descaling, and may perhaps get a final light roll pass through unpolished rolls. A 2D finish is used where appearance is of no concern. No. 2B A bright, cold-rolled finish resulting in the same manner as No. 2D finish, except that the annealed and descaled sheet receives a final light roll pass through polished rolls. This is the general-purpose cold-rolled finish that can be used as is, or as a prliminary step to polishing. No. 2BA or BA Non-standard but widely offered bright annealed finish, highly reflective surface.

Polished finishes: No. 3 An intermediate polished surface obtained by finishing with a 100-grit abrasive. Generally used where a semi-finished polished surface is required. A No. 3 finish usually receives additional polishing during fabrication. No. 4 A polished surface obtained by finishing with a 120 - 150 mesh abrasive, following initial grinding with coarser abrasives. This is a general-purpose bright finish with a visible "grain" which presents mirror reflection. No. 6 A dull satin finish having lower reflectivity than No. 4 finish. It is produced by Tampico brushing the No. 4 finish in a medium of abrasive and oil. It is used for architectural applications and ornimental where a high luster is undesirable, and to contrast with brighter finishes. No. 7 A highly reflective finish that is obtained by buffing finely ground surfaces but not to the extent of removing the "grit" lines. It is used cheifly for architecural and ornamental purposes. No. 8 The most reflective surface, which is obtained by polishing with successively finer abrasives and buffing extensively until all grit lines from peliminary grinding operations are removed. It is used for applications such as mirrors and reflectors.

Standard mechanical strip finishes: No. 1 Approximates a 2D finish for sheet. No. 2 Approximates a 2B finish for sheet. BA Bright annealed, highly reflective finish. Used extensively for automotive trim. Mill-buffed No. 2 or BA strip finish followed by buffing to produce a uniform colour and uniform reflectivity. Used for automotive trim, household hardware and for subsequent chromium plating. For more information consult: NiDi 9012, "Finishes for stainless steels". roughness in plate can initiate crevice about 8 in. (200mm), and from sheet in attack in severe environments. For such larger sizes. The finish on welded pipe services, it is necessary to negotiate normally approaches the 2B or 2D finish surface finish required with the on sheet, except in the area of the weld. producer. The finish on extruded seamless pipe is Pipe is not normally furnished to a not quite as smooth but is normally specific finish. Welded pipe is made satisfactory from the standpoint of from cold finished coils in sizes up to corrosion.

37 For the materials engineer Electropolishing is an electrochemical welded and removed from the rest of process which provides a high luster the surface just prior to final cleaning finish and is finding increased use in and inspection. applications where cleanability is a major concern, such as bioprocessing and 4. Pipe is normally ordered to either paper mill head box equipment. The ASTM A 312, which requires a final process may be described as the re- heat treatment after welding, or to verse of electroplating in that there is an ASTM A 774, which does not. Pipe electrolyte but the current is reversed to A 312 is standard for most ware- and metal is removed rather than plating house stock. Only five of the more a new layer. The electropolishing proc- common grades are covered in A ess selectively reduces the peaks and 778. A 778 tends to be used for the sharp edges that exist on the metal larger diameter sizes where the low surfaces, which in turn lessens the carbon grades have proven to have chance of product build up and eases adequate corrosion resistance in the cleaning. There is evidence that the as-welded condition. ASTM A 403 corrosion resistance is improved over and A 774 are the comparable that of mechanically polished surfaces. specifications for stainless steel Electropolishing may be performed on fittings. Large diameter welded the completed fabrication rather than stainless steel pipe spiral can be sheet, strip or other starting products. obtained to ASTM A 409. The surface roughness, that is the distance between the peaks and valleys, 5. The interior finish in the area of the is reduced about 25% through weld is often of concern. Most electropolishing. The surface may be welded pipe producers achieve a ground to a 180 to 250 grit finish before good finish in the area of the weld electropolishing but mechanical polishing but the finish desired should be on electropolished surfaces is avoided. identified in procurement to avoid misunderstandings. Purchasing guidelines 6. Standard pipe lengths are 20 ft. The following guidelines are offered (6m), but longer lengths up to 60 ft. when purchasing stainless steel to be (18m) are available. For smaller used in the fabrication of corrosion diameter lines, considerable savings resistant equipment. can be made by ordering in longer 1. Select the low carbon grades or the lengths and utilizing bends in lieu of stabilized alternates for welded fittings. fabrications that will not be solution annealed after fabrication. Standard specifications for stainless steel product forms for welded fabrica- 2. Specify a 2B finish for sheet. Specify tion are shown in APPENDIX A. The the finish the application requires for ASTM specifications do not cover plate in the procurement ducuments. assembly welds such as required to fabricate pipe assemblies, tanks and 3. Specify protective paper for sheet other process equipment. Specfications and plate to be applied at the mill for fabrication weld quality are the when special surface protection responsibility of the user and must be during storage and fabrication war- included in procurement documents. rants. The protective paper can be stripped back in the area to be

38 Part III For the design engineer

Design for corrosion design, but can be significant and have led to failures in flat bottom tanks. The services concave and dished head arrangements Much can be done in the detailed design can withstand much greater fatigue to improve corrosion resistance and loadings than can flat bottoms. obtain better service from less expensive grades.

There are two cardinal rules: 1. DESIGN FOR COMPLETE AND FREE DRAINAGE. 2. ELIMINATE OR SEAL WELD Figure 14-1 Flat Figure 14-2 Flat CREVICES. bottom, square bottom, rounded corners - worst. corners - good Tank bottoms - Figures 14-1 through corners, poor 14-6 show six common tank bottom outside. arrangements. The square corner flat bottom arrangement, Figure 14-1, invites early failure from the inside at the corner weld where sediment will collect, in- New Old creasing the probability of crevice attack. grout grout Moisture penetrating the flat bottom to / d X, &~~1j I/// pad support invites rapid crevice corrosion from the underside. The rounded bottom shown in Figure Figure 14-3 Flat Figure 14-4 Flat 14-2 is much more resistant from the bottom, rounded bottom, rounded inside, but is actually worse from the corners, grouted - corners, drip skirt outside as condensation is funnelled poor inside, poor - good inside, directly into the crevice between the tank outside. good outside. bottom and pad support. The grout used to divert such condensation, Figure 14-3, does help initially but soon shrinks back and becomes a maintenance demand itself. The drip skirt shown in Figure 14-4 is much the best arrangement for flat bottom tanks. The concave bottom and [ head bottom on supports, the dished Figure 14-5 Figure 14-6 Figures 14-5 and 14-6, are very good Concave bottom, Dished head - best and superior to all flat bottom tanks not rounded corners - inside, best out- only in corrosion resistance but also in good inside, good side, fatigue fatigue. Fatigue stresses from filling and outside, fatigue resistant considered in emptying are seldom resistant.

39 For the design engineer Tank bottom outlets - Water left Bottom corner welds - When the standing in the bottom of stainless steel side wall forms a right angle with the tanks has been a source of tank bottom bottom, the fillet weld is seldom as failures in both fresh and saline waters. smooth as shown in Figure 14-13. It is Side outlets and centre outlets, shown usually rough and frequently varies in in Figures 14-7 and 14-8, allow for width compensating for variations in fit convenient construction but invite early up. Because of the location, it is very failure of stainless steel tank bottoms. difficult to grind and blend the weld into Not only is a layer of stagnant water the adjacent sides. Debris tends to held on the tank bottom but sediment collect and is difficult to remove, leading cannot be easily flushed out. A flush to under sediment type crevice attack. side outlet and a recessed bottom outlet Unless welded from the outside as in as in Figures- 14-9 and 14-10 allow the Figure 14-14, the crevice is vulnerable to bottom to be completely drained and all crevice attack. Rounding the corner and debris and sediment to be flushed out, moving the weld to the side wall over- leaving the bottom clean and dry. The comes both short comings as shown in sloped arrangements shown in Figures Figure 14-15. This construction has 14-11 and 14-12 make it easier to flush much improved corrosion resistance and out and clean. also has better fatigue resistance.

. K LI Wed Weld eld Figure 14-7 Side Figure 14-8 Centre Figure 14-13 Figure 14-14 outlet, above outlet, above Corner weld from Corner weld from bottom - poor. bottom - poor. inside - poor both sides - poor inside, worst inside, good outside. outside.

L L 'r4 Weld Weld Figure 14-9 Side Figure 14-10 outlet, flush - Centre outlet, good. recessed - good. Figure 14-15 Side wall in lieu of corner weld - best inside, good outside, fatigue resistant.

Attachments and structurals - All attachments create potential crevice K sites. Figure 14-16 shows a tray support angle with intermittent welds adequate Figure 14-11 Side Figure 14-12 for strength. There is a severe crevice Centre outlet, between the angle and the inside wall of outlet, flush, the vessel which will become filled with sloped - best. recessed, sloped - best. debris and invite premature failure from

40 For the design engineer crevice corrosion. always be done. It is good practice to Figure 14-17shows drill a weep hole through the outer wall the same tray and must be done if the vessel is to support with a receive a stress relief or solution anneal, continuous seal weld otherwise the expansion of the trapped at the top preventing air could damage the vessel wall. unwanted material Figure 14-21 shows structural angles from finding its way F positioned so they can drain, an impor- down the wall and Figure 14-16 Tray tant factor when shutting down and into the crevice. The support, staggered flushing out. Angles should never be angle to side wall strength weld - positioned as in the top section of Figure crevice is still open adequate support, 14-22. The best position for complete from the bottom but severe crevice drainage is shown in the lower view. this is a much less severe crevice which When channels are used, drain holes vapors but not material can still enter. Figure 14-18 shows a full seal weld at the top and bottom of the tray support angle. Here the crevice is fully sealed. Worst7 1 Best Good Best Figure 14-21 Figure 14-22 Position of angles. Position of angles.

I should be drilled about every 12 in. Figure 14-17 Tray Figure 14-18 Tray (300 mm) in the centre, unless they can support, full seal, support, full seal be positioned as in the right hand view weld top - good weld top & bottom of Figure 14-23. crevice resistance. - best crevice Continuous fillet welds on support resistance beams will seal the severe beam to horizontal plate crevice shown in the -I upper section of Figure 14-24. Baffles in tanks and heat exchangers create dead spaces where sediment

I1 Figure 14-19 Figure 14-20 Worst Good Best Reinforcing pad, Reinforced pad, staggered welds - seal weld - best Figure 14-23 Position of channels. adequate strength crevice resistance. Figure 14-19 shows a reinforcing pad Continuous fillets both sides to which other attachments are fre- crevice sealed quently welded. The intermittent weld creates a severe pad-to-sidewall crevice rered inviting premature failure. It takes very fillets severe crevice little more time to complete the seal weld as shown in Figure 14-20 which should Figure 14-24 Vertical beams.

41 For the design engineer can collect and where full cleaning is Concentrated difficult. Figure 14-25 shows a cut out at solution the lower corner of a tank baffle and Figure 14-26 a cut out in the lower Concentrated Concentrated portion of a heat exchanger tube sup- solution -solution _ port plate. Both arrangements reduce debris collection and facilitate cleaning. Dilute G 9 ~solution Heaters and inlets - Heaters should Poor Good be located so they do not cause hot Figure 14-28 Poor and good designs for mixing concentrated and dilute I solutions. stainless steel pipe rather than butt weld, as in Figure 14-29. On larger diameter pipe, over 2 in. (50 mm), a Figure 14-25 Figure 14-26 Heat backing ring as shown in Figure 14-30 Corner baffle cut exchanger, baffle is often used. Both designs may be out - good. cut out - good. satisfactory for those services where the spots on the vessel wall. In Figure 14-27, stainless steel alloy has adequate the poor location of heaters creates hot crevice corrosion resistance. Because spots which in turn may result in higher of the crevice formed, these designs corrosion in the area between the heater often lead to unnecessary corrosion in and vessel wall. The good design avoids aggressive environments and are not hot spots by centrally locating the heater. recommended. The backing ring has When a concentrated solution is the further disadvantage of protruding added to a vessel, it should not be into the flow stream, which in turn can introduced at the side as shown in the cause product build up or unnecessary poor design of Figure 14-28. Side turbulence. is introduction causes concentration and Very often stainless steel piping uneven mixing at the side wall. With the installed as commercial quality, that is good design, mixing takes place away from the side wall. It is also good design practice to introduce feed below the :N=.g liquid level to avoid splashing and drying above the liquid line.

Pipe welds - It is frequently conven- Figure 14-29 Figure 14-30 Pipe ient to socket weld small diameter Socket weld joint weld made with severe crevice backing ring - severe crevice. without imposing code standards such as the ASME or the American Petro- Heater Heater - leum Institute, API, which require full penetration butt welds. When procure- Poor Good ment does not require full penetration smooth ID butt welds, it is all too com- Figure 14-27 Poor and good designs mon to have a beautiful looking weld for the location of heaters in a vessel. from the outside but incomplete pen-

42 For the design engineer etration on the The hand fed filler metal method is inside, such as more widely used in the chemical shown in Figure process industry but the experience of 14-31. Many the particular company or welders, corrosion failures strongly influences the selection. It is originate in crev- important that the root bead have ices created by adequate and uniform amounts of filler incomplete pen- metal melted into the weld for best etration at the root Figure 14-31 Pipe corrosion resistance. This addition is of pipe butt welds. weld with incom- readily obtained with consumable Since ASTM does plete penetration - inserts or by skilled welders using the not cover fabrica- severe crevice. hand fed filler metal method. tion, procurement specifications must There are a number of automatic specify full penetration and smooth ID GTAW machines available for root pass for the root bead of butt welds when the and fill welding. The root pass can be weld quality is not covered by other made using an insert, with automatic specifications. wire feed or in thin wall pipe, single The preferred pipe butt welding pass welds can be made without filler procedure to insure high quality root metal addition. The ID root contour of welds is the use of GTAW for the root automatic welds is very consistent and pass with an inert gas backing. In it is an excellent process to use where manual root pass welds, the hand fed the economics are favourable. Auto- filler metal technique or the use of matic GTAW is a particular advantage consumable inserts is commonly used. for tubing and pipe 2 in. (50 mm) diam- Figure 14-32 shows some standard eter and less. consumable insert designs. Properly Three good pipe-to-flange welding made welds with either technique can arrangements are shown in Figures provide a crevice free ID surface with 14-33, 14-34 and 14-35. The recessed minimum bead convexity or concavity. arrangement shown in 14-33 avoids the need for machining or grinding smooth the surface of the weld on the flange face in Figure 14-34. Both these arrangements are suitable when the flange is of the same material as the pipe. Neither is suitable when carbon Class 1 Class 2 steel or ductile iron flanges are used on stainless steel pipe. In this case a stub end arrangement shown in Figure 14-35 is preferred. In the case of pressure

Class 5 Class 3 I __ ILI Class 4 I Figure 14-33 Pipe Figure 14-34 Pipe recessed flange flush, pipe and Figure 14-32 Standard consumable and pipe, same flange same alloy - inserts, (from AWS A5.30). alloy - good. better.

43 For the design engineer

. piping, the flange ...Z" design must also Undrainedwwaterfilm -- fi be in accordance I 0 - to 77 71, 77 77 77 77 */ 7 with the applicable design or fabrica- I -0 A tion specification. For piping and Undrained water film heat exchanger Figure 14-35 Stub tubing to drain end, flange carbon B completely, it is steel or ductile iron necessary to slope - very good. the piping or heat Figure 14-36 exchanger just enough so that water will (A) Horizontal (standard) - poor. drain and not be trapped where the pipe (B) Horizontal sloped - very good. or tubing sags slightly between support points. Figure 14-36 shows how a water film tends to remain in horizontal runs of pipe or tubing and how water drains when sloped.

44 Appendix A Specifications for stainless steel for welded fabrication ASTM A240 - "Heat resisting chro- ASTM A312 - "Seamless and welded mium and chromium-nickel stainless austenitic stainless steel pipe." steel plate, sheet and strip for pres- ASTM A403 - "Wrought austenitic sure vessels." stainless steel piping fittings." A240 is the basic specification for A312 (pipe) and A403 (fittings) are the procurement of stainless steel for older specifications for welded welded fabrication. A240 requires austenitic stainless steel pipe for solution annealing at the mill. This aggresive environments developed for, specification includes 40 austenitic, 4 and widely used by, the chemical duplex and 16 ferritic grades. Caution: industry. Both products require a Care must be taken to select the low solution anneal after welding. Most of carbon or stabilized grades for corrosion the common stainless steel are resistant services, as the higher carbon covered. Caution: Care must be taken grades, used primarily in heat resistant to select the low carbon or stabilized applications, are included. grades for corrosion resistant services, as the higher carbon grades are also ASTM A262 - "Detecting included in A 312. Sizes from 1/8 inch to susceptibility to intergrannular attack 30 inch diameter are included. in austenitic stainless steels." A262 is a supplemental specification ASTM A778 - "Welded, unannealed that covers five tests that can be in- austenitic stainless steel tubular cluded in procurement specifications products." when maximum resistance to ASTM A774 - "As welded austenitic intergrannular attack is required. When stainless steel fittings for general A262 is used, the criteria to be met in corrosive services at low and moder- the test (practice) must be included as ated temperatures." pass/fail criteria are not part of A262. A778 (pipe) and A774 (fittings) are used where the low carbon and stabilized ASTM A264 - "Stainless chromium- grades can be used in the as welded nickel steel-clad plate, sheet and condition. Soluti6n annealing after strip." welding is not required. Only low carbon A264 is the specification for the clad and stabilized grades are included in construction using the austenitic grades these specifications. Sizes from 3 covered in A240. inches to 48 inches are covered.

ASTM A265 - "Nickel and nickel-base ASTM A409 - "Welded large diameter alloy-clad steel plate." austenitic steel pipe for corrosive or A265 is the specification for clad con- high temperature service." struction using the ten highly alloyed A409 covers light wall, spiral welded, as nickel and nickel-base grades covered well as straight seam welded, pipe 14 under separately identified ASTM B inches to 30 inches in diameter. Solution section specifications. annealing is required unless waived. Fourteen grades are covered. Caution: Care must be taken to select the low carbon or stabilized grades for corrosion resistant services, as the higher carbon grades are also included. There is no specification for fittings.

45 Additional requirements: Few ASTM pipe and fitting specifica- 2. Inert gas backup on the inside of tions require pickling after production. the pipe during welding to minimize oxidation and heat tint. ASTM specifications do not cover shop 3. Matching composition or higher Mo fabrication of pipe and fittings. The user content filler metal for Mo-containing must develop his own specifications for grades. butt welding and fabrication to pipe drawings. Important points to include 4. Protection of piping with protective are the following: end caps to minimize contamination during shipment and storage. 1. Full penetration, smooth ID, TIG made root beads.

Bibliography

AN S I/AWS D1 0.4 - 86, Recommended American Welding Society, Welding Practices for Welding Austenitic Chro- Handbook, Volume 4, Seventh Edition. mium-Nickel Stainless Steel Piping and Tubing. ASM International, Metals Handbook, Ninth Edition, Volume 6, Welding, ANSI/AWS D1 0.11 - 87, Recommended Brazing and Soldering. Practices for Root Pass Welding of Pipe Without Backing. AWS B2.1 - 84, Standard for Welding Procedure and Performance Qualifica- ASTM A380, Standard Recommended tion. Practice for Cleaning and Descaling Stainless Steel Parts, Equipment, and ASME Boiler and Pressure Vessel Systems. Code, Section Nine.

American Iron and Steel Institute, Fabrication and Post-Fabrication Welding of Stainless Steels and Other Cleanup of Stainless Steels, by Arthur Joining Methods, distributed by Nickel H. Tuthill, NiDI Technical Series Development Institute, Publication Ng 10 004. Ng 9002.

Acknowledgement

The authors are indebted to Richard B. valuable technical comments. Hitchcock and David E. Jordan for their

46 This report was prepared by Richard E. Avery Arthur H. Tuthill Consultants to the Nickel Development Institute I

The Nickel North America Nickel Development Institute 214 King Street West - Suite 510 Development Toronto, Ontario Canada MSH 3S6 Institute is Telephone 1 416 591 7999 Fax 1 416 591 7987 an international Europe Nickel Development Institute nonprofit 42 Weymouth Street London, England W1 N 3C organization Telephone 44 171 493 7999 Fax 44 171 493 1555 serving the needs of Nickel Development Institute European Technical Information Centre people interested The Holloway, Alvechurch Birmingham, England 848 7B Telephone 44 152 758 4M in the application of Fax 44 152 758 5562 nickel and Japan Nickel Development Institute nickel-containing 11-3, 5-chome, Shimbashi Minato-ku, Tokyo, Jan materials. Telephone 813 3436 7953 Fax 81 3 3436 7734 Central & South America Nickel Development Institute cto nstituto doeMetals No Frrosos R. Prapora, 31 0 Sao Pauo-SP, Brasil 04008-060 Telephone 55 11 887 2033 Fax 55 11 885 8124 India Nickel Development Institute 55A Uday Park (First Floor) Khel Gaon Marg Members of NIDI New Dehi 110 049 India Companhia Niquel Tocantins Telephone 91 11 686 5631 Fax Empresa de Desenvolvimento 91 11 686 3378 de Recursos Minerals 'CODEMIN" S.A. Australasia' Nickel Development Institute Falconbridge Umited PO. Box 28, 8tackburn South Victoria 3130, Australia Inco Limited Telephone 613 9878 7558 Morro do Niquel S.A. Fax 613 9894 3403 Nippon Yakin Kogyo Co., Ltd. South Korea Outokumpu Oy Nickel Development Institute Olympia Building, Room 811 PT. International Nickel Indonesia 196-7 Jamslbon-Dong, Songpa-Ku Seoul 138 229, South Korea Pacific Metals Co., Ltd. Telephone 82 2 419 6465 QNI Limited Fax 82 2 419 2088 Sherritt International Corporation Inc. China Nickel Development Institute Shimura Kako Company, Ltd. Room 677, Poly Plaza Office 8uilding 14 Dongzhimen Nandajie - Sumitomo Metal Mining Co., Ltd. Beijing, China 100027 Tokyo Nickel Company Ltd. Telephone 86 106500 1188 (ext. 3677) WMC Limited Fax - 86 10 6501 021 SEP 92,9.0 .iun WoU. may 9W'20 Printed on recycled paper in Canada Cd 97140 Nickel Development Institute Materials Workshop for Nuclear Power Plants

Program Evaluation

Please evaluate each segment and its relevance to your position at the Nuclear Regulatory Committee on a scale of 1 to 5. (1 = excellent; 2 = good; 3 = average; 4 = needs improvement; 5 = poor) Overall Relevance Topic Evaluation to Job Basics of Stainless Steel and Ni-Base Alloys Corrosion Basics Welding Stainless Steels High Strength Stainless Steels Advanced Stainless Steels Microbiologically Influenced Corrosion

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744 $kW iat d404.ea ed eadA

Nicole Paulus and Curtis Kovach Nickel Development Institute 3209 McKnight East Drive Pittsburgh, PA 15237-6423 412-369-0377 Phone 412-367-2353 Fax v

PRESENTERS '<'j Cmiii' Kovach holdsianl'.S.in 'Metalurgical' Engineering from the dniversify of Piitsburgh.

= = - =W6 and has over 40 years exieience instainless' = a -- =~~M steel research and mHrk'tt'evlopm eni;. His: work with a major domestic stainles'stee~producer specialized in"tube and pipingfor the power industry. He hasauthored more'than thirty technical publications.relted to stainless st'eel' High Performance Stainless Steels and corrosion control. I ;-. ' - - gggaggo in Condenser Applications (I hour) Since 1972, 200 power condenser tubing installa- Di: Nicole Paulhus holds an undergraduate' tions requiring about 100 million feet of tube have Basics of Stainless Steel and been made worldwide. On a megawatt or surface degree in Mechanical Engineering'and a Ph.D. Nickel-Base Alloys 11hour) area basis, more than half of this has been in nuclear in MetallurgicalEngineerng,,, from ,,.the,.Swiss. power plants. This presentation provides technical deral Institute of Technology. in' Zurich, This is a discussion of stainless steels and nickel-base highliahts of this successful new development and alloys - their chemistry, metallurgy, engineering prop- describes corrosion, mechanical, and heat transfer Switzerland, where she fdcused on 'the 'mech6n-' erties, and areas of application. Emphasis is on typ- performance; common installation and operating prac- ical properties of high nitrogens'tainless steels.. ical grades within these material classes, and on tices, and a discussion of problem areas that have selection uidelines based on tVical properties. Since 1995, she has been involved with'staihless been noted. steel market development with a special' epha- Corrosion Basics (11hr: New Stainless Steels'for, sis on the power industry. She-is'Jhe''-uithoriofC A primer on forms of corrosion that may be encoun-: Feedwater Heater-Applications '4 minutes) ,eight technical papers. - tered in power plants. Guidelines for identfying and '' -:1~.1~"~ avoiding these torms of corrosion'are given, empha- Type 439-a'nd Type 304N-'are now seeinq extensive sizing'-bo'h operating and material 'ariables. The -service in' feedwater heafers, and the 6%- molybde- WORKSHOP MATERIALS material is helpful in .designing- operating practices' *num .stainless steels are'` becming -a material of that minimize corrosion and prevent -its occurrence choice. Experience withthese' grades and with'some .Par'ticipa'nts'willbeprided itfco urseate' when' developing maintenance procedures and new. new grades that have great potenticl for high pressure DaSea on'- khors lectres' aln6ig, with designs. ' . ..: service' is documented., The technical -disussion NiDI publications related to the \V'orksho•, ':focuses on' stress corrosion.and'strength corparisoni topics. Participants will also receive -lst oll. Welding Stainless Steel houri among alloys. . ,el-.,,. a' ri nic - bfa. - 1 o s - of r m n 'o t~ NiDI-publications, which can be ,btain edfree' of; Stainless steels and nickel-base alloys offer mnay out .Microhioloyically Influenced Corrosion standing properties if they are fabricated and used . : .. ,u,. . tr ch'arge by contacting NiDI. ' ' ' 'i' properly. Welding, annealing, and pdst-weld clean- - --.. ing are discussed-in terms:.ot procedures that opti 1The correct selection arid 'use of stainless'sfeefs in ser- mize performdnce and avoid unexpected damage, ;'vice water. and'-6ther: water-handling- sstems con reducethe'risk of corrosion'degradation 'cdusedb a. ARRANGEMENTS Heat Exchanger Applications - 145 minutes) -icrobial effect .prThe funda'rrientls 'of MIC aresre-: All oishop expenses are paid for the

This dis&ussi'on covers theuses dnd'limitctions of C- --isented, as well assuggestions for minimizing risk w en Nickel. Development, Institute. The host 'utility is ventional 'stinless steel heat xchanget ;:tubing . using standard st6ihless: steel grades. -The outstandin - TUs6ea on y op Ioyidemeeting spaceaina 5,mmX~ grades.' The'growing number .of applications for the MIC resistance of the high performance stainless steeoI .projection setup. Wor s opt`ina6^e,Nel&at av~ new #high -performance stainless steels" 'are 'also ' 'andnickel-baseIIloys is documened. ' : described ith focus'on the corrosion-and mechan- ''''' ' - tim-tha 'isiconvenient for 'the` utiliy a'ncipsen' c reltrnn ' y 'icalpropertiesof these grades . Emphasis is placed - SericeWater. Systems, /4inuts - -t'ers-..,T64e:- rMshp agnai on,-tubing 'material 'selection- in 'reltidn. tocooling ' i' This segment is based oin '6NiDIsurveyconductedat " the--utilityAsselection from- the list'ofia 1vaiable water chemistry and heat exchanger operating cons- -.'all US nuclear powerplonts:' It sho'ws ha-t tes'of topics. Arr 5scl ega -"'i i r shop ditions. This discussion is helpful to those.responsible'. .'corrosion haveoccurred' in'th'servic'e' w ater'systems can~~ire-e-b7'rr'~ rea in'raTh',i "ti for maintaining the integrity of existing heat exchang- at these pants, and what replacement materials have wuksh6^' bacdes-ri Dbycialling~rePa rnuinsi'the-.,," ers and to those-planning for heat .exchanger' .. ' ben chosen'to solve theproblems. replacements. For additional information, or to N-nil The market development schedule a workshop at your site, %N0 1 and applications research please fax or mail this form to: ;\u NICKEL organization DEVELOPMENT of the primary 0¢SNSTITUTE nickel industry. Nicole Paulcs or Curt Kovacl ; -nc6r,,6r

Please contact me about a deeor)f -trSt of workshop at my site.

Name: NVi's inform to designers, s Company: engineers respo and use of materi tions. Inquiries ad architects, engineers, io it- Address:: ers, and others respons eselec- tion of materials for man i andn construction. NiDI coopera colleges and universities by furn irjg,-rle- vant information and mateia stupor City: engineering, materials sciencea industrial design education. State: Zip:: Technical service is a key part of NiDJ's- Telephone: (_) market development activity. Through its network of international consultants, Fax: ( I NiDI has at its disposal a vast wealth of technical information on nickel-containing materials and their uses. This infor- Email: mation is available to users and specifiers of these materials at no charge through NiDi's technical infor- / mation service. Nickel Developm~ent Istitute

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The Nickel Development Institute (NiDI) Publications Technical Information Service is the market development and Nickel Technical service is a key part of NiDl's applications research organization of the A quarterly magazine, Nickel was first market development activity. Through its primary nickel industry. Incorporated published in September 1985. It covers network of international consultants, NiDI and organized in 1984, NiDI directs its new and changing applications of nickel has at its disposal a vast wealth of worldwide program from its technical information on nickel-containing headquarters in Toronto, Canada. and its alloys. Nickel is distributed to a circulation list of materials and their uses. This information NiDI's objective is sustained growth in is available to users and specifiers of the use of nickel and nickel-containing 37,000 in 95 countries. Authors are drawn from NiDI's these materials at no charge through steels and alloys. Through its global NiDI's technical information service. offices and key international consultants international roster of consultants and other respected experts around the world. and contractors, NiDI carries out market Web Site development activities, market Technical Literature exploration, and applications-oriented NiDI distributes 90,000 technical wwwnidi.org technical research around the world. publications annually to designers, Introduced in December 1997, NiDI's Market development is the primary specifiers, in fact, anyone interested in the web site provides contact information for thrust of NiDl's overall program. use of nickel and nickel-containing all of our offices, details on our various NiDI's information services are materials. educational workshops, electronic copies available not only to nickel users but to NiDI's ever-growing library presently has of Communique and a request form and designers, specifiers, educators, some 278 titles. A catalogue summarizing abstracts for some of our technical fabricators and others having an the contents of each of these publications is literature. interest in nickel-containing materials available from NiDI offices around the world. and their applications. Enquiries are welcomed from architects, engineers, Communique Nickel Development Institute specification writers, and others Introduced in September 1990, publications and technical responsible for the selection of Communique is published three times information service are available free materials for manufacturing and per year. of charge to anyone construction. NiDI co-operates with Communique reviews international interested in nickel and nickel- colleges and universities by furnishing regulatory activity and other matters relevant information and materials for relating to the environmental impact of containing materials. Please contact engineering, materials science, and nickel, including occupational health any NiDI office for more information industrial design education. and safety. or visit www.nidi.org. North America Nickel Development Institute 214 King Street West -Suite 510 Toronto, Ontario Canada M5H 3S6 Telephone 1 416 591 7999 Fax 1 416 5917987 Europe Nickel Development Institute 42 Weymouth Street London, England WI N 3LQ Telephone 44 171 493 7999 Fax 44 171 493 1555 Nickel Development Institute European Technical Information Centre The Holloway, Alvechurch Birmingham, England B48 70B Telephone 44 152 758 4777 Fax 44 152 758 5562 Japan Nickel Development Institute 11-3, 5-chome, Shimbashi Minato-ku, Tokyo, Japan Telephone 81 3 3436 7953 Fax 81 3 3436 7734 Central & South America Nickel Development Institute c/o Instituto de Metais Nao Ferrosos R. Pirapora, 310 Sao Paulo-SP, Brasil 04008-060 Telephone 55 11 887 2033 Fax 55 11 885 8124 India Nickel Development Institute 55A Uday Park (First Floor) Khel Gaon Marg New Delhi 110049 Members of NiDI India Codemin S.A. Telephone 91116865631 Fax 91 11 686 3376 Companhia Nfquel Tocantins Australasia Falconbridge Limited Nickel Development Institute Inco Limited 150 Drummond Street, Suite 3 Carlton, Victoria 3053 Nippon Yakin Kogyo Co., Ltd. Australia Telephone 613 9650 9547 OUtokumpu Oy Fax 613 9650 9548 P.T. International Nickel Indonesia South Korea Pacific Metals Co., Ltd. Nickel Development Institute Olympia Building, Room 811 QNI Limited 196-7 Jamsilbon-Dong, Songpa-Ku Seoul 138 229, South Korea Sherritt International Corporation Inc. Telephone 82 2 419 6465 Shimura Kako Company, Ltd. Fax 82 2 419 2088 Sumitomo Metal Mining Co., Ltd. China Nickel Development Institute Tokyo Nickel Company Ltd. Room 677, Poly Plaza Office Building WMC Limited 14 Dongzhimen Nandajie Beijing, China 100027 Telephone 86 10 6500 1188 (ext. 3677) Printed on recycled paper in Canada Oct 98/5.0 Fax 86 10 6501 0261 i

; Membership and Structure Accomplishments

Membership in SSINA is open to a Leadership roles in many public North American producers of specialty policy and legislative issues affecting the steel products. specialty steel industry.

The "hands-on" involvement of members in a Successful prosecution of unfair trade issues relating to the industry has been a cases under U.S. trade laws. These pivotal reason for the effectiveness of SSINA. programs, a legitimate governmental response to the numerous findings of The committees are: unfair pricing and subsidization of a Board of Directors imports, have resulted in hundreds of millions of dollars of additional sales for X Superalloys Committee specialty steel producers and job • Environment Committee opportunities for their employees. a Manufacturing Committee * Health and Safety Committee a Participation in the founding and continued Steel Caucuses in the U.S. * Critical Materials Committee support of the Senate and House of Representatives. * Tax Committee * Electrical Steel Task Force a Active involvement in U.S. bilateral and • Stainless Steel Bar and Rod Task Force multilateral trade negotiations with major steel producing nations. D Stainless Steel Flat Rolled Task Force

* Stainless Steel Wire Task Force a Enactment since 1972 of federal * Stainless Steel Market legislation requiring the use of domestic Development Committee specialty steel in the performance of Department of Defense contracts, *Sponsors ensuring millions of dollars of sales by The Stainless Steel Market Development the industry to the defense sector. Committee is joined in its work by representatives from a wide range of i Effectively representing the industry's best diverse businesses sharing an interest in interests with governmental agencies in expanding the use of stainless steel. Current seeking solutions to our nation's membership includes service centers, environmental problems relating to processors, fabricators, raw material hazardous waste disposal, clean water, suppliers, design/engineering firms. clean air, and other issues. What Are Specialty Steels?

Specialty steels are high technology, high value materials produced by a unique segment of the U.S. steel industry. They differ from other steels in their high alloy content, technical properties, and special processing techniques.

Specialty steels are difficult to make and require more personal attention and labor input than other steels. Their characteristics include exceptional hardness; toughness; strength; resistance to heat, corrosion or abrasion; and combinations of these characteristics.

Specialty steels are identified as: * Stainless Steels * High Speed and Tool Steels * High Temperature Alloys (Superalloys) • Electrical Steels * Magnetic and Electronic Metals

Specialty steels touch our daily lives in a wide range of uses. They are essential in today's industrialized economy and serve critical applications in aircraft; automobiles; appliances; communications, electronic, marine and power-generating equipment; home utensils and cutlery; construction products; food and chemical processing plant equipment; and medical, health, and sports equipment.