Surface Hardening of Stainless Steels

Total Page:16

File Type:pdf, Size:1020Kb

Surface Hardening of Stainless Steels Surface Hardening of Stainless Steels Materials and Applications Series, Volume 20 SURFACE HARDENING OF STAINLESS STEELS Euro Inox Euro Inox is the European market development asso- Full members ciation for stainless steel. Members of Euro Inox Acerinox include: www.acerinox.com • European stainless steel producers; Aperam • national stainless steel development associations; www.aperam.com • development associations of the alloying element Outokumpu industries. www.outokumpu.com The prime objectives of Euro Inox are to create aware- ness of the unique properties of stainless steel and Associated members to further its use in existing applications and in Acroni new markets. To achieve these objectives, Euro Inox www.acroni.si organises conferences and seminars and issues guid- British Stainless Steel Association (BSSA) ance in printed and electronic form, to enable archi- www.bssa.org.uk tects, designers, specifiers, fabricators and end users Cedinox to become more familiar with the material. Euro Inox www.cedinox.es also supports technical and market research. Centro Inox www.centroinox.it ConstruirAcier www.construiracier.fr Industeel www.industeel.info Informationsstelle Edelstahl Rostfrei www.edelstahl-rostfrei.de International Chromium Development Association (ICDA) www.icdacr.com International Molybdenum Association (IMOA) www.imoa.info Nickel Institute www.nickelinstitute.org Paslanmaz Çelik Derneği (PASDER) www.turkpasder.com Stowarzyszenie Stal Nierdzewna www.stalenierdzewne.pl SWISS INOX www.swissinox.ch ISBN 978-2-87997-395-1 SURFACE HARDENING OF STAINLESS STEELS Contents Surface Hardening of Stainless Steels 1 Introduction 2 Second edition 2015 2 Principle 3 (Materials and Applications Series, Volume 20) 3 Thermochemical diffusion methods 5 © Euro Inox 2013-2015 3.1 Carburising 6 3.2 Gas nitriding 7 Publisher 3.3 Plasma (ion) nitriding and liquid nitriding 10 Euro Inox 3.4 Nitrocarburising 11 Avenue des Cerisiers 15, bte. 1 3.5 Boriding or boronising 13 1030 Brussels 4 Applied energy methods 14 Phone +32 486 50 37 53 4.1 Induction hardening 14 E-mail: [email protected] 5 Costs 15 Internet: www.euro-inox.org 6 Summary 16 7 References 17 Author Alenka Kosmač, Brussels (B) Cover photos Expanite, Hillerød (DK) (left) iStockphoto (top right) Bodycote Hardiff, Düsseldorf (D) (bottom right) Copyright notice This work is subject to copyright. Euro Inox reserves all rights of translation in any language, reprinting, re-use of illustrations, recitation and broadcasting. No part of this publication may be reproduced, stored Disclaimer in a retrieval system or transmitted in any form or by Euro Inox has made every effort to ensure that the any means, electronic, mechanical, photocopying, information presented in this document is techni- recording or otherwise, without the prior written per- cally correct. However, the reader is advised that the mission of the copyright owner, Euro Inox. Violations material contained herein is for general information may be subject to legal proceedings, involving mon- purposes only. Euro Inox and its members, specifically etary damages as well as compensation for costs disclaim any liability or responsibility for loss, dam- and legal fees, under Luxembourg copyright law and age or injury, resulting from the use of the information regulations within the European Union. contained in this publication. 1 SURFACE HARDENING OF STAINLESS STEELS 1 Introduction Scratch resistance of Surface hardening provides surfaces for the surface is often different consumer products and ensures requested for high- that stainless home appliances, household visibility applications. objects, cutlery and highly exposed objects maintain their pleasing appearance and durability. It is also necessary in industrial applications where exceptional wear resist- ance combined with corrosion resistance are needed. A wide range of such applica- Stainless steel is widely used in applications tions can be found in [1, 2, 3, 4, 5]: in which corrosion resistance is of high im- • consumer goods portance. In many end-uses, the material is • household appliances also expected to have a hard, scratch-resist- • food and beverage industry ant surface. When improved wear resistance • mobile devices is required, surface engineering provides • industrial fluid handling solutions. Industrially proven processes are • industrial and consumer fasteners available that improve surface hardness, • valve and pump parts scratch and wear resistance. • medical applications • marine applications Properties most often expected from sur- • automotive components face hardening [1, 2]: • axis and rotating parts • scratch resistance • surface hardness above 900 HV0.05 • unchanged corrosion resistance Surface hardening can • reduced friction coefficient be used in many differ- • no dimensional change ent areas, from building • minimal or no change in visual appearance and architecture to the food and beverage • no cracking or flaking of the hardened layer industry. Photo: Heat • minimal or no change in surface roughness & Surface Treatment, • no pre-treatment Eindhoven (NL) • no post-treatment • enhanced lifetime and reduced downtime and costs • weldability • suppression of fretting/galling (adhesion) 2 SURFACE HARDENING OF STAINLESS STEELS 2 Principle Surface hardening includes a wide variety There are three distinctly different ap- of techniques. Most often it is used to im- proaches to the various surface-hardening prove the wear resistance of parts without methods [7]: affecting the softer, tough base material 1. Thermochemical diffusion methods, necessary to resist impact occurring during which modify the chemical composition operation. of the surface with hardening species such as carbon, nitrogen and boron. Dif- Wear involves the physical removal of fusion methods allow effective hardening material from a solid object. It can be of the entire surface. They can be used for divided into three categories: abrasive, both single parts and batches. adhesive and fatigue wear. 2. Applied energy or thermal methods, Abrasive wear is when two surfaces rub which do not modify the chemical com- together and the harder surface grinds position of the surface but rather improve away the softer. It can be characterized properties by altering the surface struc- by a rough appearance. Often, work ture – that is they produce a quench-hard- hardening of the surface can occur. ened surface, without additional alloying Adhesive wear, like abrasive wear, is species. They can be used to harden the caused by loaded surfaces rubbing to- entire surface or only part of it (selective gether. With adhesive wear, high local- surface-hardening). ized temperatures are created by friction 3. Surface coating or surface-modification at the tips of opposing asperities on rub- methods, which involve the intentional bing surfaces. These tips can deform and build-up of a new layer on the steel sub- “weld” together, due to localized temper- strate. atures. They either break and fall away as debris or are cold-welded together. Various process methods for the surface Fatigue wear occurs whenever a surface hardening of steels are shown in Table 1. is subjected to repeated high-stress These long-established techniques are load. Wear rates are less affected by tem- continually improved and remain among perature than is corrosion [6]. the most widely applied ones. This publica- tion discusses the most important surface- hardening methods used on stainless steels (marked in italics in the following table). 3 SURFACE HARDENING OF STAINLESS STEELS Table 1. Process methods for the surface hardening of steels [7] Diffusion methods Coating and surface modification Carburising Hard chromium plating Nitriding Electroless nickel plating Nitrocarburising Thermal spraying Carbonitriding Weld hardfacing Boriding or boronising Chemical vapour deposition Thermal diffusion process Physical vapour deposition1 Applied energy methods Ion implantation Flame hardening Laser surface processing Induction hardening Laser-beam hardening Electron-beam hardening Vickers test scheme The pyramidal diamond An indentation left in case- indenter of a Vickers hardness hardened steel after a Vickers tester. hardness test. The difference in length of both diagonals and the illumination gradient, are both classic indications of an out-of-level sample. This is not Source: Wikipedia; Vickers hardness test a good indentation. Photos: R. Tanaka (middle); Dennis M. Clarke, (right) 1 Physical vapour deposition is discussed in the Euro Inox publication Colouring Stainless Steel, Materials and Applications Series, Volume 16, http://www.euro-inox.org/pdf/map/ColouringStainlessSteel_EN.pdf 4 SURFACE HARDENING OF STAINLESS STEELS 3 Thermochemical diffusion methods Traditional thermochemical treatment on ties and tribological properties [8]. Some stainless steel is associated with a loss of recently developed processes, in contrast, corrosion resistance as nitrogen and car- do not diminish the corrosion resistance of bon react with chromium to form carbides/ stainless steels. nitrides, thus withdrawing chromium from solid solution. In the case of stainless steels, hardening by thermochemical treat- ment has been considered bad practice or a compromise between corrosion proper- Table 2. Typical characteristics of thermochemical diffusion treatments for stainless steels [7, 8] Process Typical case Case Process Name of case temperature depth hardness Process characteristics °C µm HV Nitriding/Carburising/Nitrocarburising Hardest cases from
Recommended publications
  • Wear Behavior of Austempered and Quenched and Tempered Gray Cast Irons Under Similar Hardness
    metals Article Wear Behavior of Austempered and Quenched and Tempered Gray Cast Irons under Similar Hardness 1,2 2 2 2, , Bingxu Wang , Xue Han , Gary C. Barber and Yuming Pan * y 1 Faculty of Mechanical Engineering and Automation, Zhejiang Sci-Tech University, Hangzhou 310018, China; [email protected] 2 Automotive Tribology Center, Department of Mechanical Engineering, School of Engineering and Computer Science, Oakland University, Rochester, MI 48309, USA; [email protected] (X.H.); [email protected] (G.C.B.) * Correspondence: [email protected] Current address: 201 N. Squirrel Rd Apt 1204, Auburn Hills, MI 48326, USA. y Received: 14 November 2019; Accepted: 4 December 2019; Published: 8 December 2019 Abstract: In this research, an austempering heat treatment was applied on gray cast iron using various austempering temperatures ranging from 232 ◦C to 371 ◦C and holding times ranging from 1 min to 120 min. The microstructure and hardness were examined using optical microscopy and a Rockwell hardness tester. Rotational ball-on-disk sliding wear tests were carried out to investigate the wear behavior of austempered gray cast iron samples and to compare with conventional quenched and tempered gray cast iron samples under equivalent hardness. For the austempered samples, it was found that acicular ferrite and carbon saturated austenite were formed in the matrix. The ferritic platelets became coarse when increasing the austempering temperature or extending the holding time. Hardness decreased due to a decreasing amount of martensite in the matrix. In wear tests, austempered gray cast iron samples showed slightly higher wear resistance than quenched and tempered samples under similar hardness while using the austempering temperatures of 232 ◦C, 260 ◦C, 288 ◦C, and 316 ◦C and distinctly better wear resistance while using the austempering temperatures of 343 ◦C and 371 ◦C.
    [Show full text]
  • Effects of Carburization Time and Temperature on the Mechanical Properties of Carburized Mild Steel, Using Activated Carbon As Carburizer
    Materials Research, Vol. 12, No. 4, 483-487, 2009 © 2009 Effects of Carburization Time and Temperature on the Mechanical Properties of Carburized Mild Steel, Using Activated Carbon as Carburizer Fatai Olufemi Aramidea,*, Simeon Ademola Ibitoyeb, Isiaka Oluwole Oladelea, Joseph Olatunde Borodea aMetallurgical and Materials Engineering Department, Federal University of Technology, Akure, Ondo State, Nigeria bMaterials Science and Engineering Department, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria Received: July 31, 2009; Revised: September 25, 2009 Due to the complexity of controlling parameters in carburization, there has been relatively little work on process variables during the surface hardening process. This work focuses on the effects of the carburizing temperature and time on the mechanical properties of mild steel carburized with activated carbon, at 850, 900 and 950 °C, soaked at the carburizing temperature for 15 and 30 minutes, quenched in oil, tempered at 550 °C and held for 60 minutes. Prior carburization process, standard test samples were prepared from the as received specimen for tensile and impact tests. After carburization process, the test samples were subjected to the standard test and from the data obtained, ultimate tensile strength, engineering strain, impact strength, Youngs’ moduli were calculated. The case and core hardness of the carburized tempered samples were measured. It was observed that the mechanical properties of mild steels were found to be strongly influenced by the process of carburization, carburizing temperature and soaking time at carburizing temperature. It was concluded that the optimum combination of mechanical properties is achieved at the carburizing temperature of 900 °C followed by oil quenching and tempering at 550 °C.
    [Show full text]
  • Ferritic Nitrocarburizing Gears to Increase Wear Resisitance And
    Ferritic Nitrocarburizing Gears tOI Increase Wear Resistance and Reduce Distortion Loren ,JI, Epler uaHtygear manufacturing depends on controlled toler- asa gaseous territic nitrocarl:mrizillg process and patented by ances and geometry. As a re ult, ferritic nillocarburizing Lucas Industries in 1961. Lucas demonstrated that they could ha become the heat treat process of choice for many produce surface layers identical to those produced in salt bath gear manufacturers. The primary reason for this are: processes using an endothermic, ammonia-based atmosphere. The process is performed at low temperatures, i.e. less than The process was classified as a "thermochemical susfece critical treatment" that involved !he diffusion of both nitrogenand car- 2. The quench methods increase fatigue strength by up to, L25% bon into the surface of a metal at a temperature below the au tell- without distorting. Ferritlc nitrocarboriziag is used in place ite transforrnation temperature. The process would yield .3 single of carburizing and hardening, carbonitriding, nltriding or in phase epsilon layer with an atomic weight of Fep3' The ingle conjunction wi.th conventional and induction hardening. phase layer makes !:heproduct much more wear resistant than gas 3. h establishes gradient base haronesses, i.e, eliminates egg- or ionnitriding, according to Dawc and Trantner 0). shell effect on TiN, TiAlN,. ere. etc. [II 1982, lronbeund HeatTreat developed Ni.tmwear® using In addition, the process can also be applied to hobs, broaches, similar atmo pheres in a fluidized bed medium. Subsequently. drills and other cutting tools. Jack Ross, owner and founder of lronbound,. patented and HisUJry, Fenitic nitrocarburizing was first established in licensed the process to Dynamic Metal Treating.
    [Show full text]
  • Effect of Alloying Elements on Heat Treatment Behavior of Hypoeutectic
    Materials Transactions, Vol. 47, No. 1 (2006) pp. 72 to 81 #2006 The Japan Institute of Metals Effect of Alloying Elements on Heat Treatment Behavior of Hypoeutectic High Chromium Cast Iron Sudsakorn Inthidech1;*, Prasonk Sricharoenchai1 and Yasuhiro Matsubara2 1Department of Metallurgical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok10330, Thailand 2Department of Metallurgical Engineering, Faculty of Engineering, Chulalongkorn University, Bangkok10330, Thailand The relationship between hardness and volume fraction of retained austenite (V ) was investigated in heat-treated 16 mass% and 26 mass%Cr hypoeutectic cast irons with and without addition of a third alloying element of Ni, Cu, Mo and V. In as-hardened state, hardness changed remarkably depending on the V . Overall, Ni and Cu decreased hardness but Mo increased it. Hardness increased in 16 mass%Cr cast iron but decreased in 26 mass%Cr cast iron by V addition. The V increased with Ni, Cu and Mo addition but diminished with V addition in 16 mass%Cr cast iron. In 26 mass%Cr cast iron, Ni and Mo increased the V but Cu and V reduced it. Higher austenitization caused more V . Curves of tempered hardness showed an evident secondary hardening due to precipitation of special carbides and transformation of destabilized austenite into martensite. High tempered hardness was obtained in the specimens with high V in as-hardened state. Maximum tempered hardness (HTmax) was obtained when V was less than 20% and it increased with an increase in Mo content. The HTmax slightly increased with V content in 16 mass%Cr cast iron and decreased in 26 mass%Cr cast iron.
    [Show full text]
  • Effect of Tempering Conditions on Secondary Hardening of Carbides
    materials Article Effect of Tempering Conditions on Secondary Hardening of Carbides and Retained Austenite in Spray-Formed M42 High-Speed Steel Bowen Liu 1,*, Tian Qin 2, Wei Xu 1, Chengchang Jia 1,*, Qiuchi Wu 2, Mingying Chen 2 and Zhe Liu 2 1 Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China; [email protected] 2 School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China; [email protected] (T.Q.); [email protected] (Q.W.); [email protected] (M.C.); [email protected] (Z.L.) * Correspondence: [email protected] (B.L.); [email protected] (C.J.); Tel.: +86-15-210-565-349 (B.L.) Received: 30 October 2019; Accepted: 7 November 2019; Published: 11 November 2019 Abstract: In this study, the effect of tempering conditions on microstructure, grain size, and carbide phase compositions of spray-formed high-speed steel after quenching at 1180 ◦C was studied. The influence of carbide phase, size of carbides, and retained austenite content on secondary hardening of the steel was analyzed by field emission scanning electron microscope (FESEM), transmission electron microscope (TEM), electron backscattered diffraction (EBSD), and differential scanning calorimetry (DSC); the hardness, microhardness of carbide, and bending strength were tested. The results show that M3C, M6C, M7C3, and MC carbides may precipitate at different tempering temperatures and the transformation of the retained austenite can be controlled by tempering. The phase composition of carbides, microstructure, and retained austenite content strongly influences the performance characteristics of M42 high-speed steel after tempering.
    [Show full text]
  • Comparing and Contrasting Carbonitriding and Nitrocarburizing
    This article was originally published in the July 2016 issue of Industrial Heating magazine and is republished here with permission The Heat Treat Doctor® COMPARING AND CONTRASTING CARBONITRIDING AND NITROCARBURIZING Daniel H. Herring THE HERRING GROUP Inc. 630-834-3017 [email protected] The terminology of heat treating is sometimes challenging. Heat treaters can be inconsistent at times, using one word when they really mean another. You have heard the terms carbonitriding and nitrocarburizing and know they are two different case-hardening processes, but what are the real differences between them? Let’s learn more. Part of our confusion stems from the fact that years ago carbonitriding was known by other names – “dry cyaniding,” “gas cyaniding,” “nicarbing” and (yes) “nitrocarburizing.” The Carbonitriding Process Carbonitriding is a modified carburizing process, not a form of nitriding. This modification consists of introducing ammonia into the carburizing atmosphere in order to add nitrogen into the carburized case as it is being produced (Fig. 1). Carbonitriding is typically done at a lower temperature than carburizing, from as low as 700-900°C (1300-1650°F), and for a shorter time than carburizing. Since nitrogen inhibits the diffusion of carbon, a combination of factors result in shallower case depths than is typical for carburized parts, typically between 0.075 mm (0.003 inch) and 0.75 mm (0.030 inch). It is important to note that a common contributor to non-uniform case depth during carbonitriding is to introduce ammo- nia additions before the load is stabilized at temperature (this is a common mistake in furnaces that begin gas additions upon setpoint recovery rather than introducing a time delay for the load to reach tempera- ture).
    [Show full text]
  • Carbonitriding and Hard Shot Peening for High-Strength Gears Yoshihisa Miwa, Masayuki Suzawa, Yukio Arimi, Yoshihiko Kojima, and Katsunori Nishimura Mazda Motor Corp
    Carbonitriding and Hard Shot Peening for High-Strength Gears Yoshihisa Miwa, Masayuki Suzawa, Yukio Arimi, Yoshihiko Kojima, and Katsunori Nishimura Mazda Motor Corp. ABSTRACT CUE HARONESS HARONESS CUE OEtrM A new process for manufacturing high- OISTRIBUTION --E CORE HARONESS strength gears has been developed to meet the requirement of automobile transmission minia- r turization. The points of the process are to GRAIN SIZE increase the shot peening intensity and to MICROSTRUCTURE perform optimal control of the initial (before FATIGUE CARBIOES shot peening) microstructure by heat treatment STREMGTH MON-MARTEMSITIC corresponding with the peening intensity in OEFEtTS -r SURFACEUOU-METALLIC LAYER order to obtain higher residual compressive IuCLUSlONS stress. INTERGRANULAR i TOUGHMESS The new process, named Carbonitriding and Hard Shot Peening in Mazda, brings a much RESlOUAL COYIRESIVE STRESS higher fatigue strength than the one obtained by the conventional carburizing and shot peening process. Fig. 1 METALLURGICAL FACTORS AFFECTING ON THE FATIGUE STRENGTH OF GEARS 1. Introduction A higher drivability, stability in therefore, it is necessary to set a suitable driving, and fuel efficiency are required for i~ardnessdistribution by heat treatment using automobiles and the new systems to meet these clean material. However, in order to augment requirements have been developed. This can the fatigue strength furthermore, it is nec- be seen, for example, in multi-valve system, essary to make use of residual compressive super charging in engines, 4 WD or 4 WS, etc. stress more positively. In addition, the height of engine hood has For enlargement of the residual compressive been lowered in body designing for reducing stress, it is most effective to increase the air resistance.
    [Show full text]
  • Induction Hardening on Drive Axle Shaft and It's
    www.ierjournal.org International Engineering Research Journal (IERJ) Special Issue Page 1197-1201, June 2016, ISSN 2395-1621 Induction Hardening on Drive axle shaft and it’s FEA #1Aniket A. Deshmukh, #2Prof. D.H. Burande 1 PG student, Automotive Engineering, Mechanical Engineering Department, Savitribai Phule Pune University, Pune, Maharashtra, India. 2Associate professor, Mechanical Engineering Department, Savitribai Phule Pune University, Pune, Maharashtra, India. Abstract: This work deals with increasing strength of steel drive axle shafts by placing an extra bush support. It includes the modeling of shaft in CATIA. Drive shaft made up of MS material will be analyzed first. Stress and deformation will be the output of analysis. The meshing and boundary condition application will be carried using Hypermesh; Structural analysis of shaft will be carried out using ANSYS. Re-designing the shaft placing a bush for additional support in the length of shaft, and applying induction hardening process at the place of bush support for increasing the strength and reducing the deflection of the shaft. The design optimization also improves the performance of drive shaft. Keywords: Finite Element Analysis, Drive axle shaft, Induction hardening, Bush support. 1. INTRODUCTION Power is transmitted from engine to differential through propeller shaft, Axle shaft is connected between Hardening process is used for parts that wears while differential and wheel. It takes torque from engine. In this operating. During hardening core of the part does not get paper, drive axle shaft of Bolero automobile is thought of affected. Hardening increases wear resistance of a for the study. This axle shaft is semi-floating kind.
    [Show full text]
  • Carburizing & Carbonitriding
    CARBURIZING & CARBONITRIDING A TRADITIONAL SURFACE HARDENING TREATMENT WITH MODERN PROCESS CONTROLS WHAT IS IT? HOW IS IT DONE? General Description of Carburizing & Carbonitriding Equipment & Process Carburizing is a process of controlled diffusion of carbon into Solid, molten salt and gaseous carbon-carrying medium may the surface of a component, followed by quenching and be employed, however, the first two are now rarely used. tempering, with the objective of increasing the component’s Nitrex offers gas carburizing in computer controlled integral surface hardness. The process is generally applicable to low quench and pit gas carburizing furnaces. A full range of case carbon and low alloy steels. There are two carburizing depths if feasible with an economically derived limit of process types available commercially – vacuum carburizing approximately 0.250” (6.4 mm). In addition, Nitrex offers and conventional carburizing. The former is described in a vacuum carburizing which is described in a separate separate brochure, and conventional carburizing is company publication. discussed here. The sequence of operations is as follows : In this thermal process ferrous alloys are heated to above • parts are appropriately fixtured, loaded into the furnace, their transformation temperature and exposed to carbon rich and the process is initiated atmosphere. Processing temperatures in conventional • carburizing typically are in the 1450°F - 1900°F (790°C - computers and/or process controllers are programmed to 1040°C) range. The diffusion of carbon into the part and the conduct the process automatically, subsequent quench leads to a part with a hard, wear • at the end of the process the load is either direct resistant surface and a tough, shock resistant core.
    [Show full text]
  • Ultra-Fast Boriding for Improved Energy Efficiency and Reduced Emissions in Materials Processing Industries
    ANL/ESD/12-16 Ultra-fast Boriding for Improved Energy Efficiency and Reduced Emissions in Materials Processing Industries. Final Report. Project Period: 9/30/2008 – 9/30/2011 (extended to 12/31/2011) Energy Systems Division About Argonne National Laboratory Argonne is a U.S. Department of Energy laboratory managed by UChicago Argonne, LLC under contract DE-AC02-06CH11357. The Laboratory’s main facility is outside Chicago, at 9700 South Cass Avenue, Argonne, Illinois 60439. For information about Argonne and its pioneering science and technology programs, see www.anl.gov. Availability of This Report This report is available, at no cost, at http://www.osti.gov/bridge. It is also available on paper to the U.S. Department of Energy and its contractors, for a processing fee, from: U.S. Department of Energy Office of Scientific and Technical Information P.O. Box 62 Oak Ridge, TN 37831-0062 phone (865) 576-8401 fax (865) 576-5728 [email protected] Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor UChicago Argonne, LLC, nor any of their employees or officers, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.
    [Show full text]
  • History of the Hardening of Steel : Science and Technology J
    HISTORY OF THE HARDENING OF STEEL : SCIENCE AND TECHNOLOGY J. Vanpaemel To cite this version: J. Vanpaemel. HISTORY OF THE HARDENING OF STEEL : SCIENCE AND TECHNOLOGY. Journal de Physique Colloques, 1982, 43 (C4), pp.C4-847-C4-854. 10.1051/jphyscol:19824139. jpa- 00222126 HAL Id: jpa-00222126 https://hal.archives-ouvertes.fr/jpa-00222126 Submitted on 1 Jan 1982 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. JOURNAL DE PHYSIQUE Colloque C4, suppZ4ment au no 12, Tome 43, de'cembre 1982 page C4-847 HISTORY OF THE HARDENING OF STEEL : SCIENCE AND TECHNOLOGY 3. Vanpaemel Center for historical and socio-economical studies on science and technology Teer EZstZaan 41, 3030 Leuven, SeZgim (Accepted 3 November 1982) Abstract. - The knowledge of the hardening phenomenon was achieved through a very cumulative process without any dis- continuity or 'scientific crisis' . The history of the hardening shows a definite interrelationship between techno- logical approach (or the application-side) and academic science . The hardening of steel appears to have been an operation in common use among the early Greeks The Greek and Roman smiths knew, from experience, how to control the.
    [Show full text]
  • The Stainless Steel Family
    The Stainless Steel Family A short description of the various grades of stainless steel and how they fit into distinct metallurgical families. It has been written primarily from a European perspective and may not fully reflect the practice in other regions. Stainless steel is the term used to describe an extremely versatile family of engineering materials, which are selected primarily for their corrosion and heat resistant properties. All stainless steels contain principally iron and a minimum of 10.5% chromium. At this level, chromium reacts with oxygen and moisture in the environment to form a protective, adherent and coherent, oxide film that envelops the entire surface of the material. This oxide film (known as the passive or boundary layer) is very thin (2-3 namometres). [1nanometre = 10-9 m]. The passive layer on stainless steels exhibits a truly remarkable property: when damaged (e.g. abraded), it self-repairs as chromium in the steel reacts rapidly with oxygen and moisture in the environment to reform the oxide layer. Increasing the chromium content beyond the minimum of 10.5% confers still greater corrosion resistance. Corrosion resistance may be further improved, and a wide range of properties provided, by the addition of 8% or more nickel. The addition of molybdenum further increases corrosion resistance (in particular, resistance to pitting corrosion), while nitrogen increases mechanical strength and enhances resistance to pitting. Categories of Stainless Steels The stainless steel family tree has several branches, which may be differentiated in a variety of ways e.g. in terms of their areas of application, by the alloying elements used in their production, or, perhaps the most accurate way, by the metallurgical phases present in their microscopic structures: .
    [Show full text]