Titanium Alloy Guide
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TITANIUM ALLOY GUIDE Company An RTI International Metals, Inc. Company CONTENTS Page Introduction - Facts About Titanium and the Periodic Table .............................................................. 1 Why Select Titanium Alloys? ...................................................... 2-5 Guide to Commercial Titanium Alloys and Their Mill Product Forms ...................................................... 6-7 Basic Titanium Metallurgy .......................................................... 8-9 Machining Titanium ................................................................ 10-11 Forming Titanium .................................................................... 12-14 Welding Titanium .................................................................... 14-15 INTERNET Properties of Commercially WEBSITE Pure Titanium and Titanium Alloys ................................... 16-36 Guaranteed Minimum Properties This publication is also RMI 6Al-4V Alloy Products................................................... 37 available for viewing or Properties After Heat Treatment reproduction purposes of Various RMI Titanium Alloys ....................................... 38-42 on our website at: RMI Service and ISO Approvals .................................................. 43 www.RMITitanium.com. References .................................................................................... 44 RMI Capabilities .......................................................................... 45 PROPERTIES OF PURE ELEMENTAL TITANIUM AT ROOM TEMPERATURE ATOMIC ATOMIC NUMBER WEIGHT 22 47.9 OXIDATION STATES BOILING POINT ˚C 4,3 3289 MELTING POINT ˚C 1670 Ti SYMBOL 4.51 (Ar)3d24s2 DENSITY Titanium ELECTRON CONFIGURATION hcp Crystal Structure Heat of Vaporization 9.83 MJ/kg Lattice Parameters c=0.468 nm Specific Heat 518 J/kg ˚K a=0.295 nm Magnetic Susceptibility 3.17 x 10-6 cm3/g Atomic Volume 10.64 cm3/mol Magnetic Permeability 1.00005 Covalent Radius 1.32Å Modulus of Elasticity 100 GPa Color Dark Grey Poisson's Ratio 0.32 Hardness 70 to 74 BHN Solidus/Liquidus Temp. 1725˚C Coefficient of Thermal Beta Transus Temp. 882˚C -6 Cover and Back Expansion 8.4 x 10 /˚C Thermal Neutron Absorption Electrical Resistivity 42 µohm-cm Cross Section 5.6 Barnes Photo Descriptions Thermal Conductivity 20 W/m•˚K Electronegativity 1.5 Pauling's Heat of Fusion 292 kJ/kg 1.– Heat Exchangers 2.– Offshore Drilling Platform Cover Back 3.– F-22 Fighter 1. 4.– Recreational 5. Applications 5.– Commercial 2. 6. Aerospace 3. 6.– Medical Implants 7. 7.– Automotive 4. Applications 8. 8.– Naval Vessels TITANIUM ALLOY GUIDE 1 INTRODUCTION Titanium has been recognized as an application in seawater, marine, brine element (Symbol Ti; atomic number 22; and aggressive industrial chemical and atomic weight 47.9) for at least 200 service over the past fifty years. Today, years. However, commercial production titanium and its alloys are extensively of titanium did not begin until the used for aerospace, industrial and 1950’s. At that time, titanium was consumer applications. In addition to recognized for its strategic importance aircraft engines and airframes, titanium as a unique lightweight, high strength is also used in the following alloyed, structurally efficient metal for applications: missiles; spacecraft; critical, high-performance aircraft, such chemical and petrochemical as jet engine and airframe components. production; hydrocarbon production The worldwide production of this and processing; power generation; originally exotic, “Space Age” metal desalination; nuclear waste storage; and its alloys has since grown to more pollution control; ore leaching and than 50 million pounds annually. metal recovery; offshore, marine deep- Increased metal sponge and mill sea applications, and Navy ship product production capacity and components; armor plate applications; efficiency, improved manufacturing anodes, automotive components, food technologies, a vastly expanded market and pharmaceutical processing; base and demand have dramatically recreation and sports equipment; lowered the price of titanium products. medical implants and surgical devices; Today, titanium alloys are common, as well as many other areas. readily available engineered metals that compete directly with stainless and This booklet presents an overview of specialty steels, copper alloys, nickel- commercial titanium alloys offered by based alloys and composites. RMI Titanium Company. The purpose of this publication is to provide As the ninth most abundant element in fundamental mechanical and physical the Earth’s Crust and fourth most property data, incentives for their abundant structural metal, the current selection, and basic guidelines for worldwide supply of feedstock ore for successful fabrication and use. producing titanium metal is virtually Additional technical information can be unlimited. Significant unused found in the sources referenced in the worldwide sponge, melting and back of this booklet. Further processing capacity for titanium can information, assistance, analysis and accommodate continued growth into application support for titanium and its new, high-volume applications. In alloys, can be readily obtained by addition to its attractive high strength- contacting RMI Titanium Company to-density characteristics for aerospace headquartered in Niles, Ohio, USA, or use, titanium’s exceptional corrosion any of its facilities and offices resistance derived from its protective worldwide listed in this booklet. oxide film has motivated extensive 1 2 H 22 He PERIODIC TABLE 3 4 5 6 7 8 9 10 Li Be Ti B C N O F Ne 11 12 13 14 15 16 17 18 Na Mg Al Si P S Cl Ar 19 20 21 24 25 26 27 28 29 30 31 32 33 34 35 36 K Ca Sc V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe 55 56 57 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 Cs Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn 87 88 89 104 105 106 107 108 109 110 Fr Ra Ac Rf Db Sg Bh Hs Mt Uun 58 59 60 61 62 63 64 65 66 67 68 69 70 71 Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu 90 91 92 93 94 95 96 97 98 99 100 101 102 103 Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr The information provided on the following pages is intended for reference only. Additional details can be obtained by contacting the Technical staff of RMI Titanium Company through its Sales Department or through the website at www.RMITitanium.com. TITANIUM ALLOY GUIDE 2 WHY SELECT TITANIUM ALLOYS? Figure 1 Attractive Mechanical Properties Titanium and its alloys exhibit a unique combination of mechanical and physical properties and corrosion resistance which have made them desirable for critical, demanding aerospace, industrial, chemical and energy industry service. Of the primary attributes of these alloys listed in Table 1, titanium’s elevated strength-to- Table 1. Primary Attributes of Titanium Alloys · Elevated Strength-to-Density Ratio (high structural efficiency) · Low Density (roughly half the weight of steel, nickel and copper alloys) Figure 2 · Exceptional Corrosion Resistance (superior resistance to chlorides, seawater and sour and oxidizing acidic media) · Excellent Elevated Temperature Properties (up to 600˚C (1100˚F)) density represents the traditional primary incentive for selection and design into aerospace engines and airframe structures and components. Its exceptional corrosion/erosion resistance provides the prime motivation for chemical process, marine and industrial use. Figure 1 reveals the superior structural efficiency Figure 3 of high strength titanium alloys compared to structural steels and aluminum alloys, especially as service temperatures increase. Titanium alloys also offer attractive elevated temperature properties for application in hot gas turbine and auto engine components, where more creep- resistant alloys can be selected for temperatures as high as 600˚C (1100˚F) [see Figure 2]. The family of titanium alloys offers a wide spectrum of strength and combinations of strength and fracture Cyclic Stress Amplitude toughness as shown in Figure 3. This (ksi) permits optimized alloy selection which 100 (MPa) Figure 4 can be tailored for a critical component 600 based on whether it is controlled by 80 Ti6Al-4V Air Steam strength and S-N fatigue, or toughness NaCl Solution and crack growth (i.e., critical flaw size) 60 400 in service. Titanium alloys also exhibit excellent S-N fatigue strength and life 40 Air 12 Cr Steel in air, which remains relatively 200 unaffected by seawater (Figure 4) and 20 NaCl Solution other environments. Most titanium 12 Cr Steel alloys can be processed to provide high 0 0 fracture toughness with minimal 103 105 107 109 environmental degradation (i.e., good Cycles to Failure SCC resistance) if required. In fact, the TITANIUM ALLOY GUIDE 3 lower strength titanium alloys are generally resistant to stress corrosion cracking and corrosion-fatigue in aqueous chloride media. Figure 5 For pressure-critical components and vessels for industrial applications, titanium alloys are qualified under numerous design codes and offer attractive design allowables up to 315˚C (600˚F) as shown in Figure 5. Some common pressure design codes include the ASME Boiler and Pressure Vessel Code (Sections I, III, and VIII), the ANSI (ASME) B31.3 Pressure Code, the BS-5500, CODAP, Stoomwezen and Merkblatt European Codes, and the Australian AS 1210 and Japanese JIS codes. Corrosion and Erosion Resistance presence of common background or Titanium alloys exhibit exceptional contaminating