Comprehensive nuclear materials 2 08 nickel alloys properties and characteristics

Comprehensive nuclear materials 2 08 nickel alloys properties and characteristics Comprehensive nuclear materials 2 08 nickel alloys properties and characteristics Comprehensive nuclear materials 2 08 nickel alloys properties and characteristics Comprehensive nuclear materials 2 08 nickel alloys properties and characteristics Comprehensive nuclear materials 2 08 nickel alloys properties and characteristics Comprehensive nuclear materials 2 08 nickel alloys properties and characteristics Comprehensive nuclear materials 2 08 nickel alloys properties and characteristics

2.08 Nickel Alloys: Properties and Characteristics T Yonezawa Tohoku University, Japan ß 2012 Elsevier Ltd All rights reserved 2.08.1 Introduction 234 2.08.2 2.08.2.1 2.08.2.1.1 2.08.2.1.2 2.08.2.2 2.08.2.2.1 2.08.2.2.2 2.08.2.3 2.08.2.3.1 2.08.2.3.2 2.08.2.4 2.08.2.4.1 2.08.2.4.2 2.08.3 2.08.3.1 2.08.3.2 2.08.3.3 2.08.3.4 2.08.3.5 2.08.3.6 2.08.3.7 2.08.3.7.1 2.08.3.7.2 2.08.3.8 2.08.4 2.08.4.1 2.08.4.2 2.08.4.3 2.08.4.4 2.08.4.5 2.08.4.6 2.08.4.6.1 2.08.4.6.2 2.08.4.6.3 2.08.5 References Nickel and Nickel Alloy Systems Ni and Ni–Cu Alloys Chemical compositions, physical properties, and mechanical properties Applications to nuclear power industrial fields Ni–Cr–Fe and Ni–Cr–Fe–Mo Alloys Chemical compositions, physical properties, and mechanical properties Applications to nuclear power industrial fields Ni–Mo–Fe, Ni–Mo–Cr–Fe, and Ni–Cr–Mo–Fe Alloys Chemical compositions, physical properties, and mechanical properties Applications to nuclear power industrial fields Other Ni-Based Alloys Chemical compositions, physical properties, and mechanical properties Applications to nuclear power industrial fields Fabrication of Ni-Based Alloys Melting Hot Forming Cold Forming Heat Treatment Descaling and Pickling Grinding and Machining Welding Weldability Welding materials and example of welding condition Applicable Specifications Corrosion Resistance and Stress Corrosion Cracking Resistance In Air and in Water In Seawater and Chloride Solution In Caustic Solutions In Hydrochloride Gas, Chlorine, and Hydrofluoric Acid In High-Temperature Water In High-Temperature Gases Oxidation Nitriding Sulfidation Summary 234 235 235 239 241 241 244 250 250 253 253 253 253 254 254 254 255 256 257 257 257 257 257 258 258 258 261 262 262 262 263 263 264 264 265 265 Abbreviations ASME ASTM BWR American Society of Mechanical Engineering American Society for Testing and Materials Boiling water reactor CRDM EBW fcc FCAW GTAW HTGR Control rod drive mechanism Electron beam welding Face-centered cubic Flux cored arc welding Gas tungsten arc welding High-temperature gas-cooled reactor 233 234 Nickel Alloys: Properties and Characteristics Precipitation hardening at about 715 C after solution annealing at a high temperature near 1075 C HTTR High-temperature engineering HTGR test reactor IGSCC Intergranular stress corrosion cracking LBW Laser beam welding MA Mill-annealed MAG Metal active gas welding MIG Metal inert gas welding PWR Pressurized water reactor PWSCC Primary water stress corrosion cracking SAW Submerged arc welding SCC Stress corrosion cracking SG Steam generator SMAW Shielded metal arc welding TT Thermally treated or thermal treatment HTH 2.08.1 Introduction Nickel was first used as an alloying element for steels in the mid-eighteenth century The development of corrosion-resistant steels was started in the nineteenth century.1,2 These studies led to the development of various kinds of stainless steels, particularly in the early 1900s Particularly, the 300 series austenitic stainless steels were developed and became the ‘most widely used tonnage’ materials in the twentieth century The nickel–copper Alloy 400 (Monel 400, UNS N04400) was developed as the first nickel-based alloy at the beginning of the twentieth century.3 This alloy was developed as an alternative chloride-corrosionresistant material to austenitic stainless steel Nickel is a less noble element than copper; however, it is more noble than iron and zinc It exhibits higher corrosion resistance than iron in most environments due to the formation of denser and more protective corrosion films with superior passivation characteristics compared to iron Nickel has superior corrosion resistance in caustic or nonoxidizing acidic solutions, and in gaseous halogens It can be relatively easily alloyed with various elements such as chromium, molybdenum, iron, and copper Many nickel-based alloys have been developed and applied as corrosion-resistant alloys in various environments, as well as creep-resistant alloys in high-temperature applications.4 Based on their excellent properties, nickel-based alloys have been widely applied in a number of fields, for example, the aerospace industry, chemical industries, and electricity generation plants In the nuclear power industry, nickel-based alloys have been used in pressurized water reactors (PWRs) and boiling water reactors (BWRs) since their initial development in the early 1950s In particular, Alloys X-750 (UNS N07750) and X-718 (UNS N07718) have been widely applied, for example, for jet-engine blades, due to their excellent creep strength A high-creep-strength material is one that is highly resistant to stress relaxation at high temperatures Alloys X-750 and 718 have therefore been applied as bolting and spring materials for PWRs and BWRs Alloy 600 (UNS N06600) has superior resistance to stress corrosion cracking (SCC) in boiling 42% MgCl2 solution as high-chloride solutions.5 In the Shippingport and Yankee Rowe reactors, 347 stainless steel was used as a steam generator (SG) tube material (The Shippingport reactor was the first full-scale nuclear powered electricity generation plant (prototype reactor), and the Yankee Rowe reactor was the first commercial PWR.) Beginning with the Connecticut Yankee PWR, the next electricity generation plant, Alloy 600 was used as the SG tube material, and then subsequently applied in PWRs worldwide, due to its superior SCC resistance in high-chloride solutions Among the other superior properties of Alloy 600, its thermal expansion coefficient is noted to be between that of ferritic steels and austenitic steels Based on this, the residual stress and strain for dissimilar weld joints of ferritic steels and austenitic steels can be minimized by the use of Alloy 600 and its compatible weld metals In nuclear power plants, ferritic steels and austenitic steels are widely used as the main component materials, especially for the pressure boundary Numerous dissimilar metal weld joints are therefore found in nuclear power plants Alloy 600 and its weld metals such as Alloys 82, 132, and 182 have also found widespread application in such plants Nickel-based alloys were developed not only as corrosion-resistant materials but also as heatresistant materials These alloys are suitable for various components and parts in light water reactors, heavy water reactors, gas reactors, etc The detailed features and various physical properties of these nickel-based alloys are described in the following sections 2.08.2 Nickel and Nickel Alloy Systems Nickel by itself is a very versatile corrosion-resistant metal and has a higher strength at elevated temperatures than steel Nickel forms a complete solid solution Nickel Alloys: Properties and Characteristics 235 Atomic percent nickel 10 20 30 40 50 60 70 80 90 100 1600 1455 ؇C 1400 L 1200 Temperature ( ЊC) 1084.87 ؇C 1000 800 600 354.5 ؇C 65.5 400 354.4 ؇C Tc (Cu,Ni) α1 + α2 200 0 10 20 30 Cu 50 60 40 Weight percent nickel 70 80 90 100 Ni Figure Copper–nickel binary phase diagram with copper (as shown in Figure 1), manganese, and gold.6 Nickel forms a peritectic with iron (as shown in Figure 2) and eutectics with many elements, such as chromium (as shown in Figure 3), molybdenum (as shown in Figure 4), silicon, titanium, aluminum, niobium.6 Nickel can form solid solutions with many elements and intermetallic compound with aluminum, titanium, niobium, and so on The ternary constitutional diagram for the iron–nickel–chromium isothermal section at 650  C shown in Figure indicates a wide region covered by the face-centered cubic (fcc) structure of nickel But the fcc region is shrunk in the ternary constitutional diagram at 600  C for nickel–chromium– molybdenum system, as shown in Figure In this alloy system, sigma phase and other intermetallic phases are found based on a composition range.6 The effects of alloying elements on the properties of nickel-based alloys are summarized in Table Commercially pure nickel and various nickel-based alloys are representative of the newly developed materials during the twentieth century These materials are typically encountered in various industrial systems, including chemical and petrochemical processing, aerospace engineering, fossil fuel and nuclear power generation, energy conversion, solar energy conversion, thermal processing and heat treatment, oil and gas production, pollution control and waste processing, marine engineering, pulp and paper industry, agrichemicals, industrial and domestic heating, and electronics and telecommunication, among others Various nickel-based alloys, including binary, ternary, and other complex systems, were also developed in the twentieth century The main features and applications of these commercially pure nickel and nickel-based alloys are summarized in Figure Detailed properties and features of these nickel and nickel-based alloys are described in the following sections The several of these nickel-based alloys have been applied or designed to various nuclear reactor materials as shown in Table 2.08.2.1 Ni and Ni–Cu Alloys 2.08.2.1.1 Chemical compositions, physical properties, and mechanical properties The chemical compositions of nickel and typical nickel–copper alloys are shown in Table 3, along with those of other nickel-based alloys Alloy 200 (UNS N02200) is a commercially pure (99.6%) wrought nickel Alloy 201 (UNS N02201) is the low-carbon version of Alloy 200 These alloys have good mechanical properties and good resistance to corrosion at low to moderate temperatures in 236 Nickel Alloys: Properties and Characteristics Atomic percent nickel 10 20 30 40 50 60 70 80 90 100 1600 1538 ؇C 1514 ؇C 1400 1394 ؇C (δ-Fe) L 1455 ؇C 1440 ؇C 67 20 40 60 80 100 800 1200 Tc(α-Fe) Tc(FeNi3) 700 Temperature (ЊC) 600 500 1000 (γ-Fe,Ni) Tc(γ-Fe,Ni) 400 912 ؇C 300 800 770 ؇C 200 Tc(α-Fe) 20 40 60 600 Tc(γ -Fe,Ni) 517 ؇C 73 400 347 ؇C 4.9 (α-Fe) 50 80 100 354.3 ؇C FeNi3 64 200 Fe 10 20 30 40 50 60 Weight percent nickel 70 80 90 100 Ni Figure Iron–nickel binary phase diagram Atomic percent chromium 10 20 30 40 50 60 70 80 90 1900 100 1863 ؇C 1700 L Temperature (ЊC) 1500 1455 ؇C 1345 ؇C 1300 (Cr) 1100 (Ni) 900 700 590 ؇C γЈ 500 Ni 10 20 30 40 50 60 Weight percent chromium Figure Nickel–chromium binary phase diagram 70 80 90 100 Cr Nickel Alloys: Properties and Characteristics 10 Atomic percent molybdenum 30 40 50 60 20 70 80 90 100 2700 2623 ؇C 2500 2300 L Temperature (ЊC) 2100 1900 1700 1500 1455 ؇C 1362 ؇C 1300 1309 ؇C (Ni) 1100 867 ؇C Ni4Mo (Mo) NiMo 907 ؇C 900 Ni3Mo 700 Ni 10 20 30 40 50 60 70 Weight percent molybdenum 80 90 100 Mo Figure Nickel–molybdenum binary phase diagram Cr 10 90 20 80 30 pe rce n αЈ + γ 50 rom ch σ 60 40 ium σ+α σ+γ 70 nt rce pe ht 60 αЈ + σ 50 ht We ig 70 ig We t ir on αЈ 40 30 80 20 90 α+γ γ 10 α Fe 10 20 30 60 40 50 Weight percent nickel Figure Iron–nickel–chromium ternary phase diagram (at 650  C) 70 80 90 Ni 237 238 Nickel Alloys: Properties and Characteristics Mo 10 90 20 80 s+α A+α α α P+ δ+ σ+A P δ+ erc ht p A 50 σ 40 A 30 γ+ 80 γ+P γ+ δ m 70 nu de We ig A lyb mo P P+ nt 50 60 rce 60 δ pe 40 70 t igh We en tn ick el 30 20 γ+σ 90 10 γ Ni 10 20 30 40 50 60 70 Weight percent chromium 80 90 Cr Figure Nickel–chromium–molybdenum ternary phase diagram (at 600  C) caustic solutions such as NaOH or dilute deaerated solutions of common nonoxidizing mineral acids such as HCl, H2SO4, or H3PO4.7 The mechanical properties of Alloy 200 at elevated temperatures are shown in Figures and 9.3 Alloy 200 is typically limited to use at temperatures below 315  C At higher temperatures, Alloy 200 products can suffer from graphitization, which can severely compromise the properties of the material Alloy 200 is susceptible to embrittlement after longterm heating in the range of 425–760  C, due to carbide precipitation along grain boundaries.4 For service above 315  C, Alloy 201 is preferred.7 The reason for the good corrosion resistance of Alloys 200 and 201 is the fact that the standard oxidation–reduction potential of nickel is more noble than that of iron and less noble than that of copper Due to nickel’s high overpotential for hydrogen evolution, hydrogen is not easily discharged from any of the common nonoxidizing acids, and a supply of oxygen is necessary for rapid corrosion to occur Hence, in the presence of oxidizing species such as ferric ions, cupric ions, nitrates, peroxides, or oxygen, nickel can corrode rapidly The outstanding corrosion-resistance characteristics of Alloy 200 to caustic soda and other alkalis have led to its successful use in caustic evaporator tubes.7 The nickel–copper Alloy 400 is a complete solidsolution alloy that can be hardened only by coldworking Alloy 400 contains about 30–33% copper in a nickel matrix and has similar characteristics as those of Alloy 200 It has high strength and toughness over a wide temperature range and good resistance to many corrosive environments Alloy 400 exhibits excellent resistance to corrosion in many reducing media It is also generally more resistant to attack by oxidizing environments compared to higher coppercontent alloys It is also widely used in marine applications Alloy 400 products exhibit low corrosion rates in flowing seawater, whereas in stagnant conditions, crevice and pitting corrosion can be induced It is also resistant to SCC and pitting in most fresh and industrial waters Alloy 400 is highly resistant to hydrofluoric acid at all concentrations and at all temperatures up to their boiling points It is therefore widely used in components for seawater applications, salt units, crude distillation, and as a structural material in chemical plants.8 Alloy K-500 (UNS N05500) is a precipitationhardened version of Alloy 400 It contains aluminum Nickel Alloys: Properties and Characteristics Table 239 The effects of alloying elements various properties of nickel-based alloys Alloying elements Main feature for aqueous corrosion Main feature for high-temperature applications Other benefits Ni Provides corrosion resistance to caustic solutions and dilute deaerated solutions of nonoxidizing mineral acids Improves chloride SCC Provides resistance to oxidizing media Enhances localized corrosion resistance Stabilization of austenitic phase Provides precipitation of g0 Thermal stability and fabricability Cr Mo Provides resistance to reducing media W Enhances localized corrosion resistance Behaves similar to Mo but less effective Ti Nb, Ta Si Affects detrimental effect for sensitization Provides solid solution hardening Provides precipitation of M23C6, M6C, MC, etc., much precipitation of MC decreases precipitation of g0 and g00 Austenitic stabilizer N Cu B, Zr Provides solid solution hardening Provides precipitation of M6C Suppress precipitation of Z phase (Ni3Ti) Provides oxidation resistance Provides precipitation of g0 Provides precipitation of g0 and g00 Provides oxidation resistance Al C Provides solid solution hardening Provides precipitation of M23C6, as benefit for notched rupture resistance Provides solid solution hardening; provides precipitation of M6C Detrimental to thermal stability Deoxidizer in melting process Increases fluidity in casting process Mechanical properties Thermal stability and mechanical properties Improves resistance to seawater La, Ce and titanium, and is hardened by the formation of submicroscopic particles of intermetallic compounds, Ni3(Ti, Al) The formation of intermetallic compounds occurs as a solid-state reaction during the thermal aging (precipitation hardening) treatment Prior to the aging treatment, the alloy component needs to be solution-annealed to dissolve any phases that may have formed during previous processing The solution annealing and aging are normally carried out in the temperature range 980–1040  C and 540–590  C, respectively Alloy K-500 has the excellent corrosion-resistant features of Alloy 400 with the added benefits of increased strength up to 600  C and hardness The alloy has low magnetic permeability and is nonmagnetic up to 134  C Some typical applications of Alloy K-500 include pump shafts, impellers, medical blades and scrapers, oil well drill collars and instruments, nonmagnetic Increases creep rupture strength Suppress precipitation of Z phase Provides oxidation resistance Deoxidizer in melting process housings and other complementary tools, electronic components, springs, and valve trains.9 The mechanical and various physical properties of nickel and typical nickel–copper alloys are shown in Tables and 5, respectively, along with those of other nickel-based alloys Physical properties at elevated temperature are shown in Tables 6–8 2.08.2.1.2 Applications to nuclear power industrial fields Based on the high thermal conductivity (see Table 6) and high corrosion resistance of nickel–copper alloys in seawater, Alloy 400 has been widely applied in boiler feed water heat exchanger tubes and shells, and Alloy 500 has found wide use for pump shafts and impellers in seawater pumps Based on such industrial applications, Alloy 400 was used for SG tubes in some CANDU reactors Ni Ni–Cr–Fe alloy Ni–Cr–Fe/ Ni–Cr–Fe–Mo P.H alloy Ni–Mo–Cr–Fe alloy Alloy 201 Ni > 99.0, C < 0.02 Low C commercial pure Ni Applicable in caustic solution above 315 ЊC Alloy 400 Ni–31Cu–2Fe (S £ 0.024) Applicable to the components for sea water, salt unit, crude distillation, etc Alloy R-405 Ni–31Cu–2Fe–0.04S Free machining grade of Alloy 400 Alloy K-500 Ni–30Cu–2Fe–0.6Ti–2.7Al P.H version of Alloy 400, up to 600 ЊC Applicable to pump-shaft, impellers, scrapers, etc Alloy 600 Ni–15Cr–8Fe Excellently resistant to in chloride SCC Applicable to structural materials Alloy 601 Ni–23Cr–8Fe–1.4Al Excellently resistant to high-temperature oxidation Applicable to oxidation-resistant parts Alloy 690 Ni–29Cr–9Fe Excellently resistant to many corrosive aqueous media, etc Applicable to structural materials Alloy 800 Fe–33Ni–21Cr Highly resistant to high-temperature oxidation Applicable to components for high-temperature use Ni–15Cr–7Fe–2.5Ti–1Nb–0.7Al Typical P.H Ni-based alloy Applicable to parts which need high tensile, creep and creep rupture properties Ni–19Cr–17Fe–3Mo–0.9Ti–0.5Al–5.1Nb Higher strength level than Alloy X-750 Applicable to parts which need high tensile, creep and creep rupture, etc Fe–25Ni–15Cr–1.3Mo–2.1Ti–0.3Al Age-hardenable alloy Good strength and oxidation resistance up to 700 ЊC Alloy X-750 Alloy 718 Ni–28Mo–5Fe–2Co Excellently resistant to hydrochloric acid But, weak to solutions with mixing of oxidant Alloy B-2 Alloy B Ni–28Mo–4Fe–2Co–Low Si, Low C Improved on corrosion resistance in heat affected zone after welding of Alloy B Alloy B-3 Ni–30Mo–2Fe–2Co–2Cr–2W–2Mn Minimized fabrication problems for Alloy B-2 Not applicable to the environment with ferric or cupric salt Ni–17Mo–16.5Cr–4.5W–5.3Fe–0.3V Excellent high resistance to oxidation, corrosion in chlorine, compounds with chlorine, oxidizing acid, etc Ni–16Mo–15.5Cr–5Fe–3.7W–2Co Improved on fabricability and long range aging characteristics of Alloy C Alloy C-4 Ni–16Mo–16Cr–2Fe–1.5Co Advanced Alloy B Superior corrosion resistance to oxidizing environment compared to Alloy B Alloy C-22 Ni–21Cr–13.5Mo–4Fe–3W–2Co Improved on corrosion resistance of Alloy C-276 in oxidizing environment Alloy 625 Ni–21.5Cr–9Mo–4Fe High creep rupture strength and high resistance to corrosion and pitting in oxidizing environment Alloy 625LCF Ni–21.5Cr–9Mo–4Fe Improved on low cycle fatigue properties and cold formability of Alloy 625 Alloy C Alloy C-276 Ni–Cr–Mo–Fe alloy Others Features Commercial pure Ni Applicable in caustic solution below 315 ЊC Alloy A286 Ni–Mo–Fe alloy Chemical compositions Ni > 99.0 Alloy 686 Ni–21Cr–16Mo–4Fe–3.7W–1.2Al High Cr content of Alloy C-276 Excellent resistance to SCC, pitting and crevice corrosion in aggressive media Alloy 59 Ni–23Cr–15.7Mo–1Fe–0.3Al Pure Ni–Cr–Mo alloy Excellent corrosion resistance and thermal stability Alloy 825 42Ni–21.5Cr–25Fe–3Mo–2.2Cu–0.9Ti Improved on aqueous corrosion resistance in a wide variety of corrosion media, modified by Alloy 800 Alloy G Ni–22Cr–19.5Fe–6.5Mo–2Cu,Nb,Co–0.8W Superior corrosion resistance to oxidizing environment, inferior corrosion resistant to reducing environment Alloy G-3 Ni–22Cr–19.5Fe–7Mo–2Cu–4Co Improved on bending characteristics of weld joints for Alloy G Alloy G-30 Ni–30Cr–15Fe–5Mo–2.7W–1.7Cu–4Co Improved on corrosion resistance in wet phosphoric acid for Alloy G Alloy N Alloy 230 Alloy X Alloy XR Ni–16.5Mo–7Cr–4Fe Excellent corrosion resistance to liquid fluoride Ni–22Cr–14W–4Co–2Mo–2Fe Excellent resistance to oxidation and nitriding, as well as high strength at high temperatures Ni–22Cr–18.5Fe–9Mo–0.6W–2Co High strength at high temperatures and good resistance to oxidation in high temperature air Ni–Cr–Fe–Mo–2Co Originally developed as a structural material for high temperature gas-cooled reactors Figure Nickel-based alloy systems and their features (dotted line: reference material, P.H.: precipitation hardened) In nuclear power plants, several of these nickel-based alloys have been applied or are suitable as materials for various components, pipes, tubes, and other parts The main applications or candidates of nickel-based alloys for various nuclear reactors are summarized in Table Nickel Alloys: Properties and Characteristics Ni–Cu alloy Alloy no Alloy 200 240 Alloy system Nickel Alloys: Properties and Characteristics Table Main applications or candidates of nickelbased alloys for nuclear reactors Type of nuclear reactor Alloys BWR PWR CANDU reactor LMFBR HTGR 600, X-750, 718, 625 600, X-750, 718, 690, 800, A286 600, X-750, 718, 690, 800 X-750, 718, 800 600, X-750, 718, 625, XR 2.08.2.2 Ni–Cr–Fe and Ni–Cr–Fe–Mo Alloys 2.08.2.2.1 Chemical compositions, physical properties, and mechanical properties The chemical compositions of typical nickel– chromium–iron and nickel–chromium–iron– molybdenum alloys are shown in Table 3, together with those of other nickel-based alloys As described earlier, nickel is a very versatile corrosion-resistant metal The addition of chromium confers resistance to sulfur compounds and also provides resistance to oxidizing conditions at high temperatures or in corrosive solutions, with the exceptions of nitric acid and chloride solutions In addition, chromium confers resistance to oxidation and sulfidation at high temperatures Alloy 600 consists of about 76% nickel, 15% chromium, and 8% iron The alloy is not precipitationhardenable and can only be hardened and strengthened by cold-working It has excellent resistance to hot halogen gases and has been used in processes involving chlorination It has excellent resistance to oxidation and chloride SCC It is widely applied as a structural material in many industrial fields owing to its strength and corrosion resistance.10 The thermal expansion coefficient of Alloy 600 is smaller than those of austenitic stainless steels and somewhat larger than those of ferritic steels, as shown in Table It is also highly resistant to sensitization in heat-affected zones during welding The alloy and its weld metals such as Alloys 82, 132, and 182 have therefore been widely used for dissimilar metal weld joints to reduce residual stresses and strains after welding Alloy 601 has a higher chromium content (about 23%) than Alloy 600 and about 1.4% aluminum The alloy is resistant to high-temperature oxidation and has good resistance to aqueous corrosion Oxidation resistance is further enhanced by its aluminum content The alloy has been applied to the muffles of heat-treatment furnaces and in catalytic convertors for exhaust gases in automobiles.11 241 Alloy X-750 contains titanium, aluminum, and niobium, and is hardened by precipitation of the g0 phase as Ni3(Ti, Al, Nb).12 Alloy 718, on the other hand, contains niobium, molybdenum, titanium, and aluminum, and is hardened by the precipitation of both the g0 phase as Ni3(Ti, Al, Nb) and the g00 phase as Ni3Nb.13 These alloys were developed as high creep-strength and high creep-rupture-strength materials for jet-engine blades and vanes in the 1940s These precipitation-hardened materials have also been used in industrial gas-turbine materials In addition, Alloy X-750 has been used as a bolting material and Alloy 718 has been applied to bellows, springs, etc for industrial products Alloy 690 (UNS N06690) was developed in the late 1960s and has a higher chromium content (about 30%) than Alloys 600 and 601 It exhibits excellent resistance to many corrosive aqueous media and high-temperature atmospheres The properties of Alloy 690 are useful in a range of applications involving nitric or nitric/hydrofluoric acid production, and as heating coils and tanks for nitric/hydrofluoric solutions used in the pickling of stainless steels, for example.14 Alloy 800 (UNS N08800) is an iron-based nickel– chromium alloy This alloy has been compared to Alloys 600 and 690 from the view point of its corrosion resistance in many environments It was introduced for industrial use in the 1950s as an oxidation-resistant alloy and for high-temperature applications requiring optimum creep and creeprupture properties Alloy 800 has been widely used as an oxidation-resistant material and is suitable for high-temperature applications due to its high resistance to s-phase embrittlement after heating in the range of 650–870  C.15 Alloy 825 (UNS N08825) was developed from alloy 800 by the addition of molybdenum (about 3%), copper (about 2%), and titanium (about 0.9%) for improved aqueous corrosion resistance in a wide variety of corrosive media In this alloy, the nickel content confers resistance to chloride-ion SCC Nickel in conjunction with molybdenum and copper gives outstanding resistance to reducing environments such as those containing sulfuric and phosphoric acids Molybdenum also enhances its resistance to pitting and crevice corrosion In both reducing and oxidizing environments, the alloy resists general corrosion, pitting, crevice corrosion, intergranular (IG) corrosion, and SCC Some typical applications include various components used in sulfuric acid pickling of steel and copper, components in petroleum refineries and petrochemical 242 Chemical compositions of nickel-based alloys Alloy Systems Alloys UNS no Ni 200 201 400 Ni–Cu Ni–Cr–Fe Cr Mo Fe N02200 ≧99.0a N02201 ≧99.0a N04400 ≧63.0a – – – – – – ≦0.40 – ≦0.40 – ≦2.50 – R-405 N04405 ≧63.0 – – K-500 N05500 ≧63.0 – 600 N06600 ≧72.0 14.0– 17.0 14.0– 17.0 21.0– 25.0 27.0– 31.0 19.0– 23.0 14.0– 17.0 17.0– 21.0 13.50– 16.00 ≦1.00 a ≧72.0 a 600M 601 690 Reference 800 Ni–Cr–Fe X-750 718 Reference A286 Ni–Mo–Fe B Ni–Mo– Cr–Fe Ni N06601 58.0– 63.0 N06690 ≧58.0 N08800 30.0– 35.0 N07750 ≧70.0a N07718 50.0– 55.0a S66286 24.00– 27.00 N10001 b b B-2 N10665 B-3 N10675 ≧65.0 C-276 N10276 b ≦1.00 1.0–3.0 14.5– 16.5 Co Mn V P S ≦0.15 ≦0.35 ≦0.020 ≦0.35 ≦0.30 ≦0.50 – – – ≦0.35 – ≦0.35 – ≦2.0 – – – – ≦2.50 – ≦0.30 ≦0.50 – ≦2.0 – – – ≦2.0 – ≦0.25 ≦0.50 – ≦1.50 – – – 6.0– – 10.0 6.0– – 10.0 b 13.0 – ≦0.15 ≦0.50 – ≦1.0 – – ≦0.010 ≦0.25 – ≦0.010 ≦0.25 – ≦0.0240 28.0– – 34.0 0.025– 28.0– – 0.060 34.0 ≦0.010 27.0– 0.35–0.85 33.0 ≦0.015 ≦0.50 – ≦0.05 ≦0.50 – ≦1.0 – – ≦0.015 ≦0.10 ≦0.50 – ≦1.0 – – ≦0.15 ≦0.50 – ≦1.0 – ≦0.10 ≦1.0 – – – – – – 2.80– 3.30 1.00– 1.50 26.0– 30.0 26.0– 30.0 27.0– 32.0 15.0– 17.0 W 7.0– – 11.0 39.5 C Si Cu Ti Al Nb (ỵTa) B La N Zr Nb Ta Niỵ Mo – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – – 2.30– – 3.15 – – – – – – – – – – – – – – – – ≦0.50 – – – – – – – – ≦0.015 ≦1.0 – – – – – – ≦0.015 ≦0.50 – 1.0– – 1.70 – – 1.0– – 3.0 – – – – – – – – – ≦1.50 – – ≦0.015 ≦0.75 0.15–0.60 – – – – – – – – ≦0.010 ≦0.50 2.25–2.75 – – – – – – ≦0.015 ≦0.015 ≦0.30 0.65–1.15 – – – – – – – – – – – – – – – – – – – – – – – ≦0.080 ≦0.35 ≦1.0 ≦0.35 – b – ≦0.08 ≦1.00 – – 1.90–2.35 4.0– 6.0 ≦2.0 – ≦0.05 ≦1.0 ≦2.5 – – – 0.70– – 1.20 4.75– ≦0.0060 5.50 – 0.0010– 0.010 – – – ≦0.02 ≦0.10 ≦1.0 ≦2.00 0.10– ≦0.040 ≦0.030 0.50 ≦1.0 0.2– ≦0.04 ≦0.03 0.4 ≦1.0 – ≦0.04 ≦0.03 0.15– 0.60 0.40– 1.0 0.20– 0.80 ≦0.35 – – – – – – – – 1.0– 3.0 4.0– 7.0 ≦3.0 ≦0.010 ≦0.10 ≦3.0 ≦3.0 ≦0.20 ≦0.030 ≦0.010 ≦0.20 ≦0.20 ≦0.50 – – – – 3.0– 4.5 ≦0.010 ≦0.08 ≦2.5 ≦1.0 ≦0.35 ≦0.04 – – – – – ≦0.10 ≦0.20 ≦0.20 94.0– 98.0 – – – – 5.0– 9.0 17.0b – ≦0.080 ≦0.50 ≦1.0 ≦1.0 – ≦0.03 – – – Nickel Alloys: Properties and Characteristics Table 252 Nickel Alloys: Properties and Characteristics content, care must be taken to avoid using this alloy in oxidizing environments Alloy B-2 (UNS N10665) is an advanced version of Alloy B It has superior corrosion resistance in weld-heat-affected zones compared to Alloy B, due to reduced carbon and silicon contents and a restricted range of iron content Alloy B-3 (UNS N10675) was developed to minimize problems associated with the fabrication of B-2 alloy components Alloy B-3 has excellent resistance to hydrochloric acid at all concentrations and temperatures.30 It also withstands sulfuric, acetic, formic, and phosphoric acids, as well as other nonoxidizing media Alloy B-3 has a special chemistry designed to achieve a level of thermal stability superior to that of Alloy B-2 It has been applied to similar components as Alloy B-2, but cannot be used in environments containing ferric or cupric salts because these salts may cause rapid corrosion failure Alloy C (UNS N10002) (nickel-based 18% chromium–16% molybdenum–5% iron–4% tungsten) is also an advanced version of Alloy B It has superior corrosion resistance to oxidizing environments compared to Alloy B due to the added chromium However, Alloy C is degraded after heating in the temperature range 650–1090  C due to the precipitation of M6C carbides and of m phase along grain boundaries Solution heat treatment is therefore necessary after welding in the case of this alloy Alloy C-276 (UNS N10276) improves upon this weakness by using reduced carbon (