Compendium

Alloy & Superalloy Catalog — Steels, Al, Ti, Ni-Co, Refractory

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Alloy & Superalloy Catalog — Steels, Al, Ti, Ni-Co, Refractory

A grade-level reference for engineering alloys with their key composition, strengthening mechanism, mechanical and physical property ranges, processing route, manufacturer, and primary application. Property numbers are pulled from the alloy producer’s published datasheets (ATI, Carpenter Technology, Haynes International, Special Metals, Howmet Aerospace, Cannon-Muskegon, Cleveland-Cliffs, Voestalpine, Voestalpine BÖHLER) and from AMS / ASTM / ISO / DIN / EN / JIS / GB specifications. Where a property varies with heat treatment, processing route (cast vs wrought vs single-crystal vs LPBF), or test direction, that variance is called out — Tier 3 is the home of the processing-property fingerprint, not a single nominal value.

For the conceptual treatment of solid-solution, precipitation, dispersion, work hardening, transformation, and grain-boundary strengthening, see mechanical-behavior-of-materials. For phase diagrams behind eutectoid steel, γ-γ′ Ni-superalloy, α-β Ti, and martensitic transformation see crystallography-phase-diagrams. For corrosion behavior see biomaterials (implant alloys) and the cross-cluster stainless-steels note.

1. Aerospace + high-temperature nickel superalloys

The Ni-superalloy family is built around an austenitic FCC γ matrix (Ni-Cr-Co-Fe-Mo-W solid solution) strengthened by ordered L12 γ′ (Ni3(Al,Ti)) precipitates, occasionally body-centered-tetragonal DO22 γ″ (Ni3Nb), and grain-boundary carbides (M23C6 / MC / M6C). Producers: Special Metals Corporation (PCC subsidiary — owns the Inconel / Incoloy / Nimonic / Udimet trademarks), Haynes International (Kokomo IN — Hastelloy / Haynes brands), ATI Specialty Materials, Cannon-Muskegon (PCC — CMSX / CM single-crystal), Carpenter Technology Powder Products.

1.1 Wrought + powder-metallurgy nickel grades

Inconel 718 (UNS N07718, AMS 5662 bar, AMS 5663 forging, AMS 5596 sheet)

  • Composition wt%: Ni 50-55, Cr 17-21, Fe balance (~17), Nb+Ta 4.75-5.5, Mo 2.8-3.3, Ti 0.65-1.15, Al 0.2-0.8, C 0.08 max. Develops Eiselstein 1965 (Special Metals predecessor Inco).
  • Strengthening: γ″ Ni3Nb DO22 (primary, ~70% of strength) + γ′ Ni3(Al,Ti) L12. γ″ is metastable and over-ages to δ Ni3Nb above ~650°C, limiting service temperature.
  • Heat treatment: solution 980°C/1 h + double age 720°C/8 h FC 620°C/8 h AC (AMS standard).
  • Properties (solution + aged): UTS 1240-1400 MPa, YS 1030-1180 MPa, elongation 12-21%, hardness 36-47 HRC, density 8.19 g/cm³, E 200 GPa, k 11.4 W/m·K, max service ~650°C (creep limit).
  • Manufacturing: VIM + VAR (double-melted standard, AMS 5663F double-melt mandatory for rotating critical, triple-melt VIM-ESR-VAR for largest forgings). PM-HIP route through Carpenter Technology Powder Products + ATI Powermet for finer microstructure. LPBF AM at EOS / SLM Solutions / Renishaw / GE Additive / Velo3D Sapphire is qualified for non-rotating ducts and rocket engine components (RocketLab Rutherford, Relativity Aeon-R, Ursa Major).
  • Applications: GE9X / GEnx / Trent 1000 turbine discs, casings, fasteners; SLS RS-25 + RL10 + Aeon-R; nuclear reactor superheater tubing; oil + gas downhole tools.

Inconel 625 (UNS N06625, AMS 5666 bar, AMS 5599 sheet, ASTM B443)

  • Composition: Ni 58 min, Cr 20-23, Mo 8-10, Nb+Ta 3.15-4.15, Fe 5 max, Ti 0.4 max, Al 0.4 max.
  • Strengthening: solid-solution by Mo + Nb; γ″ forms slowly (does not over-age in normal service). Solid-solution hardening only at elevated temperature.
  • Properties (annealed Grade 1): UTS 830-1100 MPa, YS 415-655 MPa, elongation 30-60%, density 8.44 g/cm³, max service 980°C (oxidation-limited).
  • Applications: marine bellows + exhaust on LNG carriers, chemical process piping, jet engine combustor liners + seal rings, nuclear reactor components, additive-manufactured rocket combustion chambers (SpaceX SuperDraco hypergolic engine LPBF Inconel).

Inconel 600 (UNS N06600) / 601 (UNS N06601) / 690 (UNS N06690)

  • 600: Ni 76 / Cr 15 / Fe 8; solid-solution, oxidation + carburization resistance; furnace muffles, heat-treat baskets.
  • 601: Ni 60 / Cr 23 / Al 1.4 / Fe balance; Al for oxidation, alumina scale at 1100°C; heat-treat retorts, gas-turbine combustors.
  • 690: Ni 60 / Cr 30 / Fe 9; high Cr defeats primary-water stress-corrosion cracking PWSCC; PWR steam-generator tubing replacing failed Alloy 600 — Mihama Unit 2 / Three Mile Island 1 retubes; nuclear fuel reprocessing.

Hastelloy X (UNS N06002, AMS 5754)

  • Composition: Ni 47 / Cr 22 / Fe 18 / Mo 9 / Co 1.5 / W 0.6.
  • Solid-solution; oxidation to 1200°C; toughness preserved after long exposure.
  • UTS 770 MPa RT / 250 MPa @ 870°C; widely used in jet engine combustor cans + transition ducts (CF6, CFM56, V2500, PW2000); GE Power 7HA + 9HA frame gas turbines.

Hastelloy C-276 (UNS N10276)

  • Composition: Ni 57 / Cr 16 / Mo 16 / Fe 5 / W 4 / Co 2.5 / C 0.01 max (very low for sensitization resistance).
  • Extreme aqueous corrosion resistance — sulfuric, HCl, wet Cl2, FGD flue-gas desulfurization scrubbers, pharmaceutical reactors, pulp + paper digesters, nuclear waste vitrification.
  • UTS 760 MPa, YS 355 MPa, elongation 60%, density 8.89 g/cm³.

Waspaloy (UNS N07001, AMS 5704 / 5544 / 5586)

  • Composition: Ni 58 / Cr 19.5 / Co 13.5 / Mo 4.3 / Ti 3.0 / Al 1.4 / Fe 2 max / C 0.07; developed Pratt & Whitney 1952.
  • Strengthening: γ′ Ni3(Al,Ti), 25% volume fraction; service to ~870°C.
  • Solution 1080°C/4 h OQ + age 845°C/24 h AC + 760°C/16 h AC; UTS 1410 MPa, YS 1050 MPa @ RT; 1010 MPa @ 540°C; rupture life 100 h @ 815°C / 350 MPa.
  • Turbine discs, blades (low-stage), spacers, fasteners — P&W F100 / F119 / F135, RR Trent 1000 IP turbine discs, GE F404/F414.

René 41 (UNS N07041)

  • Composition: Ni 55 / Cr 19 / Co 11 / Mo 10 / Ti 3.1 / Al 1.5; GE 1950s.
  • γ′ at ~25% vol; UTS 1410 MPa solution + aged; similar niche to Waspaloy but slightly hotter (~870°C).
  • Apollo X-15 nose + leading edges; Saturn V S-II liquid-H2 turbopump turbine blades.

Udimet 720 / U720Li (UNS N07720)

  • Composition: Ni 55 / Cr 18 / Co 14.7 / Mo 3 / W 1.25 / Ti 5 / Al 2.5 (720); Li variant Cr 16 / B 0.015 / lower C for billet conversion.
  • γ′ ~45% vol; one of the highest-strength wrought Ni superalloys; powder-met required (PM-HIP).
  • Turbine discs T700/T900 GE, modern military fighter engines.

Rene 88DT (Ni 54 / Cr 16 / Co 13 / Mo 4 / W 4 / Ti 3.7 / Al 2.1 / Nb 0.7)

  • PM-HIP grade for turbine discs in GE90 + GEnx; dual heat treat — coarse-grain rim for creep + fine-grain bore for LCF.

1.2 Cast nickel superalloys (turbine blades)

MAR-M-247 (Martin Marietta now Lockheed Martin 1970s)

  • Composition: Ni 60 / Co 10 / Cr 8.25 / Al 5.5 / Ti 1 / W 10 / Mo 0.7 / Ta 3 / Hf 1.4 / C 0.15 / B 0.015 / Zr 0.05.
  • γ′ Ni3(Al,Ti,Ta) ~60% vol; cast via investment casting at Howmet Aerospace / PCC / Doncasters / Allegheny Technologies.
  • Equiaxed (EQ), directionally solidified (DS — columnar grain along stress axis), or single-crystal (SX) form. Hf added in DS/SX to remediate grain-boundary cracking from B.
  • UTS 1100 MPa RT / 700 MPa @ 870°C; rupture 100 h @ 982°C / 207 MPa.

CMSX-4 (Cannon-Muskegon)

  • Composition: Ni 62 / Cr 6.5 / Co 9.6 / Mo 0.6 / W 6.4 / Ta 6.5 / Al 5.6 / Ti 1 / Re 3 / Hf 0.1; 2nd-generation single-crystal.
  • 70% γ′ vol; Re slows γ′ coarsening and raises creep resistance enabling service to 1100°C.
  • Solidified [001] orientation along blade-pull axis using Bridgman directional solidifier with helical grain selector. Howmet / PCC / RTX (P&W Power Systems Manufacturing) own the technology.
  • Rolls-Royce Trent 800/900/1000/XWB HP turbine blades, P&W F119/F135.

CMSX-10 (3rd-generation single-crystal)

  • Composition: Ni 69 / Cr 2 / Co 3 / Mo 0.4 / W 5 / Ta 8 / Al 5.7 / Ti 0.2 / Re 6 / Nb 0.1 / Hf 0.03.
  • Re raised to 6%; higher creep capability but Re shortage 2007-2011 forced industry pivot to lower-Re 4th-gen + Ru-bearing 5th-gen (CMSX-15, TMS-138, TMS-196).
  • CMSX-4 Plus / CMSX-4HT: optimized for hot-section recycling Re reclamation (Re costs >1400/kg sustained); supply-chain pressure drives Re recycling at Heraeus / Umicore.

GTD-444 (GE)

  • Ni-Cr-Co-Al-Ti-W-Ta-Re Re-bearing DS for industrial gas turbine 7H/9H frame stage-1 blades; service ~1010°C.

IN-738LC (Special Metals)

  • Ni 62 / Cr 16 / Co 8.5 / Mo 1.75 / W 2.6 / Ti 3.4 / Al 3.4 / Ta 1.75 / Nb 0.9 / C 0.11; conventional EQ casting; industrial gas turbines + cogeneration; Siemens Energy 8000H frame, GE 7FA/9FA stages 2-4.

Rene N5 / N6 / N515 (GE) — single-crystal blade alloys for GE90 + GEnx + F110, similar Re content 3-6%.

1.3 Strengthening mechanism summary (Ni superalloys)

The temperature ceiling for any γ-γ′ Ni superalloy is set by γ′ over-aging: above ~0.6 Tm γ′ Ostwald-ripens (rafted morphology under load) and creep dominates. Re and Ru in 2nd-5th generation SX alloys slow diffusion in γ. γ″ Ni3Nb-strengthened alloys (Inconel 718, 706, 625 at intermediate temperature) over-age to δ Ni3Nb above 650°C — δ is incoherent and contributes nothing to strength, only to grain pinning during forging. Carbides (MC primary, M23C6 secondary) decorate grain boundaries; oversize MC carbides initiate fatigue cracks and powder-met routes minimize them. See γ-γ′ section for the L12 ordering reaction.

2. Cobalt-based superalloys + wear alloys

Cobalt superalloys have a higher melting point than nickel (~1490°C vs 1453°C) and excellent hot-corrosion + thermal-fatigue resistance, but lower as-cast strength than Ni γ-γ′ alloys because Co does not form a coherent L12 precipitate analog (Co3(Al,W) was discovered 2006 but is not yet industrial). Strengthening is by solid solution + M23C6 / M6C carbides.

Stellite 6 (Co 60 / Cr 28 / W 4 / C 1.1 / Fe 3 max / Si 1 max — Deloro Stellite now Kennametal)

  • Hard-facing weld overlay applied by GTAW + PTA + laser cladding to valve seats, drill collars, pump components. Hardness 38-48 HRC as-deposited; resists adhesive + abrasive wear + galling.
  • Original Elwood Haynes 1907 patent — the founder of Haynes Stellite later split off into Haynes International (superalloys) + Stellite (hard-facing, now Kennametal).

Stellite 12 (Co 58 / Cr 30 / W 8 / C 1.4 / Si 1.4) — harder than Stellite 6, used on hot-rolling mill rolls, hot extrusion dies.

MAR-M-509 (Co 54 / Cr 24 / Ni 10 / W 7 / Ta 3.5 / Ti 0.2 / C 0.6) — cast turbine vanes (GE F404, P&W TF30); cobalt vane alloys hold the trailing-edge position because of resistance to thermal cycling.

X-40 (Co 53 / Cr 25.5 / Ni 10 / W 7.5 / Fe 1.5 / C 0.5) — first-stage vane in early GE J-79 / RR Spey; replaced in modern engines by ceramic-matrix composite (CMC) vanes.

Tribaloy T-800 (Co 54 / Mo 28 / Cr 17 / Si 3.4) — Laves-phase intermetallic Co3Mo2Si embedded in matrix; aerospace bushings, fuel pump bearings, valve plugs.

Biomedical CoCrMo F75 / F1537 / F90 (ASTM)

  • F75 — cast (Co 58 / Cr 28 / Mo 6 / C 0.35); UTS 655 MPa, YS 450 MPa; femoral knee + hip stems.
  • F1537 — wrought low-carbon (C ≤ 0.05); UTS 1170 MPa, YS 827 MPa; modular femoral heads + hip stems.
  • F90 — wrought Co 49 / Cr 20 / W 15 / Ni 10 / Fe 3; long-stem fracture-fixation plates + screws.
  • Co-ion release controversy (metal-on-metal MoM hip resurfacing — DePuy ASR recall 2010, Smith+Nephew BHR — drives Ti / ceramic alternatives in young patients). See biomaterials.

3. Iron-based superalloys

A-286 (UNS S66286, AMS 5731 / 5732 / 5734 / 5737)

  • Composition: Fe 53 / Ni 26 / Cr 15 / Ti 2.15 / Mo 1.25 / V 0.3 / Al 0.2 / C 0.05 / B 0.005.
  • γ′ Ni3(Al,Ti) precipitation in an austenitic Fe-Ni matrix; cheaper than Ni-based but capped at ~700°C service.
  • UTS 1000 MPa, YS 690 MPa solution + age; turbocharger turbine wheels (Garrett, BorgWarner), exhaust valves + manifolds (auto + heavy truck), low-pressure gas turbine discs, cryogenic fasteners (Boeing, SpaceX Falcon 9 stage-2 LOX/LNG tank bolts).

Discaloy (UNS K66220) — historical Fe-Ni-Cr γ′ alloy, displaced by A-286.

Inconel 706 (UNS N09706) — Fe-Ni superalloy with Nb + Ti for γ′ + γ″; cheaper alternative to 718 in industrial gas turbines because Co + Mo are reduced.

Pyromet 31V (Carpenter) — Fe-Ni-Cr Ti-Al γ′; exhaust valves auto.

4. Refractory metal alloys (Mo, W, Ta, Nb, Re)

The refractory metals all have BCC structure (except Re — HCP) and melting points above 2000°C. Their Achilles heel is catastrophic oxidation in air above 600-1200°C, so all in-air refractory applications require silicide / aluminide coatings or vacuum / inert atmosphere.

Mo-TZM (Mo 99 / Ti 0.5 / Zr 0.08 / C 0.03 — ASTM B387)

  • Carbide dispersion (TiC + ZrC) raises recrystallization temperature from 1100°C (pure Mo) to ~1400°C.
  • UTS 690 MPa @ RT, 415 MPa @ 1000°C; density 10.2 g/cm³; melt point 2610°C.
  • Vacuum induction melting (VIM) + arc-cast or P/M; producers Plansee (Austria), H.C. Starck, Allegheny Technologies, Climax Specialty Metals.
  • Rocket engine throat inserts (Mo-TZM unprotected in short-duration LOX/LH2), forging dies for tungsten + titanium hot isothermal forging, X-ray rotating anode targets.

Mo-La (Mo + 0.3-0.7% La2O3 dispersion strengthening, ASTM B387 Type 365)

  • Filament + glass-melting electrodes; Plansee + H.C. Starck.

Nb1Zr (UNS R04261)

  • Niobium + 1% zirconium; sodium-cooled fast reactor cladding candidate (SP-100 program); also used as superconducting RF accelerator material — purified RRR>250 SRF cavities at Tokamak Energy + LCLS-II SLAC + CERN HL-LHC at Niowave / ATI / RI.

Ta-2.5W (UNS R05252, ASTM B708)

  • Tantalum + 2.5% tungsten; UTS 580 MPa annealed; chemical process equipment (sulfuric acid heater coils, HCl reactors, pharmaceutical autoclaves) where price is justified ($300/kg sustained 2024).

C-103 (Nb-10Hf-1Ti, UNS R04295)

  • Niobium-hafnium-titanium; can be used unprotected to ~1480°C briefly; silicide-coated R512E for longer cycles.
  • Apollo Service Propulsion System nozzle extension; SpaceX Merlin + Raptor vacuum nozzle extensions; Rocket Lab Rutherford LP turbopump.
  • Producer: ATI Wah Chang (Albany OR); historical specialty.

MoSi2 (molybdenum disilicide)

  • C40 hexagonal, ductile-to-brittle above 1200°C; electric heating elements (Kanthal Super, MHI Tubes) in air furnaces to 1800°C; passivates with SiO2 scale.

W-Re (W + 3 or 26% Re) — thermocouple wire (Type C, K) for ultra-high-temperature furnaces.

5. Aluminum alloys (highlights — full catalog in aluminum-alloys)

Heat-treatable Al alloys strengthen by precipitation of metastable phases (GP zones → θ″ → θ′ → θ in 2xxx; GP zones → η′ → η in 7xxx; β″ → β′ → β-Mg2Si in 6xxx). Non-heat-treatable 1xxx, 3xxx, 5xxx work-harden only.

  • 2024-T3 (UNS A92024, AMS-QQ-A-250/5) — Al-Cu 4.4-Mg 1.5; UTS 470 MPa, YS 325 MPa, elongation 18%, density 2.78 g/cm³; airframe skins + structures, fastener stock; T3 = solution + cold worked + natural age.
  • 7075-T6 (UNS A97075, AMS-QQ-A-250/12) — Al-Zn 5.6-Mg 2.5-Cu 1.6; UTS 570 MPa, YS 505 MPa, elongation 11%, density 2.81 g/cm³; aerospace structure, high-stress airframe forgings, sporting goods.
  • 6061-T6 (UNS A96061) — Al-Mg 1.0-Si 0.6; UTS 310 MPa, YS 275 MPa, elongation 12%, density 2.7; weldable structural extrusions, bicycle frames, fuselage stringers.
  • 5083-H321 (UNS A95083) — Al-Mg 4.5-Mn 0.7 non-heat-treatable; UTS 305 MPa, elongation 16%, excellent marine + cryogenic LNG tankers (operates to -163°C in LNG service).
  • 7050-T7451 — Al-Zn 6.2-Mg 2.25-Cu 2.3-Zr; replaces 7075 in thick (>50 mm) plate; F/A-18 + 787 forgings + plate.
  • 2055-T8 — Al-Cu-Li 3rd-gen lithium alloy from Constellium; 5% lower density than 7050, 5-8% higher modulus; A350 lower wing skin + Falcon 9 propellant tank dome welds.
  • Scalmalloy (AP Works / APWorks GmbH) — Al-Mg-Sc additive-manufacturing grade for LPBF; UTS 520 MPa T6, elongation 13%; topology-optimized aerospace + automotive (Airbus A350 bracket; APWorks Light Rider e-motorcycle).

6. Titanium alloys (highlights — full catalog in titanium-alloys)

α (HCP) — stable to 882°C; β (BCC) — stabilized by V, Mo, Nb, Cr, Fe; α-β duplex — Ti-6Al-4V workhorse.

  • Ti-6Al-4V Grade 5 (UNS R56400, AMS 4928 bar, AMS 4911 sheet, ASTM B348) — Ti-6Al-4V; ~50% of all titanium ever produced. UTS 950 MPa, YS 880 MPa, elongation 14%, density 4.43 g/cm³, E 114 GPa, melt 1660°C; airframe spars + frames, engine fan blades (CFM56 / LEAP fan), 3D-printed medical implants (LimaCorporate Trabecular Titanium, Stryker Tritanium).
  • Ti-6Al-4V ELI Grade 23 (UNS R56401, ASTM F136 / F1108) — extra-low interstitial (O ≤ 0.13, N ≤ 0.05) for fracture toughness + biocompatibility; orthopedic + dental implants, cryogenic vessels.
  • CP-Ti Grade 1-4 (UNS R50250 / R50400 / R50550 / R50700) — commercially pure α titanium; ascending oxygen content drives ascending strength + descending ductility; chemical reactors, plate-heat-exchanger plates (APV, Alfa Laval, Tranter), dental crowns, marine condenser tubes.
  • β-Ti alloys:
    • Ti-15-3 (Ti-15V-3Cr-3Sn-3Al, UNS R58153) — strip + spring stock.
    • Ti-5553 (Ti-5Al-5Mo-5V-3Cr-0.5Fe, Boeing-developed) — UTS 1240 MPa, YS 1170 MPa; F-22 + 787 + 777X main landing gear, replacing 300M ultra-high-strength steel for weight savings (~30% lighter).
    • Beta-C (Ti-3Al-8V-6Cr-4Mo-4Zr, UNS R58640) — oil + gas downhole springs + tubular components; high-strength UTS 1380 MPa STA.
    • Ti-13Nb-13Zr (ASTM F1713) — biomedical β alloy E ~80 GPa (vs ~110 GPa for Ti-6Al-4V); reduces stress shielding in orthopedic implants.
    • β-21S (Ti-15Mo-2.7Nb-3Al-0.25Si) — Boeing 777 engine exhaust plug; oxidation-resistant β.
  • α / near-α high-temperature Ti:
    • Ti-1100 (Ti-6Al-2.75Sn-4Zr-0.4Mo-0.4Si-0.4O, Timet) — service to 600°C, RR Trent + Tay + V2500 compressor discs.
    • Ti-6242S (Ti-6Al-2Sn-4Zr-2Mo-0.1Si) — service to 540°C; compressor disc + blade in P&W TF30, F100 / F119 / F135 stages.
    • Ti-834 (RR-developed) — service to 600°C; Trent compressor stages.
    • Beta-CEZ (Ti-5Al-2Sn-2Zr-4Mo-4Cr, Aubert+Duval, Snecma developed) — disc material for SNECMA M88.
  • α-Ti Ti-5Al-2.5Sn (Grade 6, UNS R54520) — weldable, used for cryogenic LH2 / LOX tankage (Saturn V S-IVB common bulkhead).

7. Steels

7.1 High-strength low-alloy (HSLA) + ultra-high-strength

  • HSLA 50 / 65 / 80 / 100 (ASTM A572 grades 50, 65, 80; A656; A841) — Nb, V, Ti microalloying (~0.1% total) gives grain-refined + precipitation strengthening; UTS 480-700 MPa; bridges, ship plate, pipeline (X80 + X100 line-pipe specs at TransCanada Keystone + Gazprom).
  • HY-80 (MIL-S-16216 Grade HY-80, UNS K31820) — Ni 2.5 / Cr 1.5 / Mo 0.4 / Mn 0.4 / C 0.18 max — quench + temper; YS 550 MPa minimum; submarine pressure hulls (Los Angeles class, Trafalgar class).
  • HY-100 (UNS K32045) — Ni 2.75 / Cr 1.6 / Mo 0.5; YS 690 MPa; Seawolf-class deep-dive sections.
  • HY-130 (UNS K33450) — Ni 5 / Cr 0.6 / Mo 0.5; YS 900 MPa; experimental deep-diving subs + ASRV.
  • HSLA-115 / HSLA-100 (Ni-Cu-Nb) — Cu precipitation-hardened submarine plate replacing HY-100 (Virginia + Columbia class); cheaper + better weldability.
  • Aermet 100 (Carpenter, UNS K92580) — Ni 11 / Co 13 / Cr 3 / Mo 1.2; UTS 1965 MPa, YS 1725 MPa, KIC 110 MPa·m^0.5; aircraft landing gear (F/A-18E/F, F-35 alternative supplier).
  • AF1410 (Carpenter) — Ni 10 / Co 14 / Cr 2 / Mo 1; UTS 1620 MPa with KIC 154 MPa·m^0.5; submarine + carrier hooks + arresting cables.
  • Maraging 250 / 300 / 350 (UNS K92890 / K93120 / K93160, AMS 6512 / 6514 / 6520) — Ni 18 / Co 8-12 / Mo 3-5 / Ti 0.4-1.85 / Al 0.1; martensitic Fe-Ni matrix aged to precipitate Ni3Mo + Ni3Ti; YS 1700 / 2000 / 2400 MPa; rocket motor cases (Polaris, Trident D5, ICBM solid motors), uranium centrifuge rotors, golf-club faces, machine-tool spindles.
  • Eglin steel ES-1 (USAF Research Lab) — Fe-Co-Ni-Cr-Mo modified secondary-hardening steel; UTS ~2000 MPa with toughness ~85 MPa·m^0.5; bomb cases + bunker-busters (GBU-28).
  • Carpenter Custom 465 (UNS S46500) — Cr 11.7 / Ni 11 / Mo 1 / Ti 1.6 (PH stainless boundary case); UTS 1860 MPa H950 condition; aerospace structural fasteners + landing gear.
  • 300M (UNS K44220) — modified 4340 with Si 1.6 + V 0.07; UTS 1860 MPa; aircraft landing gear (incumbent before Ti-5553).

7.2 Tool steels

  • D2 (UNS T30402, AISI D2) — Cr 12 / Mo 1 / V 0.9 / C 1.5 high-Cr cold-work; HRC 60-62; punch + die, knives.
  • H13 (UNS T20813) — Cr 5 / Mo 1.5 / V 1 / Si 1 / C 0.4 hot-work; HRC 48-54 tempered; aluminum die-casting dies (Magna, Ryobi, Italpresse Gauss), forging dies, hot extrusion dies.
  • M2 (UNS T11302) — Mo 5 / W 6 / Cr 4 / V 2 / C 0.85 high-speed; HSS drill bits, taps, end mills.
  • A2 (UNS T30102) — Cr 5 / Mo 1 / V 0.2 / C 1 air-hardening cold-work; HRC 60-62.
  • S7 (UNS T41907) — Cr 3.25 / Mo 1.4 / V 0.3 / C 0.5 shock-resisting; chisels, punches, pneumatic hammer bits.

7.3 Stainless steels

Cr ≥ 10.5% defines stainless; passive Cr2O3 film 2-3 nm thick. ASTM A276 (wrought bar), A240 (sheet + plate), F899 (surgical instruments). UNS prefix S (austenitic + ferritic + duplex), N (Ni alloys), J (cast).

  • 304 / 304L (UNS S30400 / S30403, JIS SUS304, EN 1.4301 / 1.4307) — Cr 18 / Ni 8 austenitic; UTS 515 MPa, YS 205 MPa, elongation 40%; general kitchen + food + chemical + architectural. L = low-carbon (≤0.03%) for weld sensitization resistance.
  • 316 / 316L (UNS S31600 / S31603, EN 1.4401 / 1.4404) — Cr 17 / Ni 12 / Mo 2.5; pitting resistance over 304; marine, pharma, medical implants ASTM F138 (no longer first-line for permanent — Ti-6Al-4V ELI preferred).
  • 321 (UNS S32100) — 304 + Ti for grain-boundary stabilization; aircraft exhaust manifolds + engine ducting.
  • 17-4PH (UNS S17400, AMS 5604 / 5643 / 5825) — Cr 17 / Ni 4 / Cu 4 / Nb+Ta 0.2-0.45 precipitation-hardened martensitic; UTS 1310 MPa H900 / 1170 MPa H1025 / 1000 MPa H1150; aerospace fittings, oil + gas, valve stems, golf-club hosels; one of the most-tonnage PH stainless steels globally.
  • 15-5PH (UNS S15500) — modified 17-4 with lower Cr + δ-ferrite-free for higher transverse toughness; UTS 1310 MPa H900; aerospace.
  • 13-8 Mo PH13-8Mo (UNS S13800) — Cr 13 / Ni 8 / Mo 2.25 / Al 1.1 (Al replaces Cu for finer η-NiAl precipitate); UTS 1517 MPa H950; aerospace bulkheads + landing-gear secondary structures.
  • 305 (UNS S30500) — 304 + Ni 11-13 for cold-heading + deep-drawing.
  • 322 / Carpenter Custom 455 (UNS S45500) — Cr 12 / Ni 8.5 / Cu 2.3 / Ti 1.2 PH; aerospace.
  • Custom 465 (UNS S46500) — discussed §7.1.
  • Duplex 2205 (UNS S31803 / S32205, EN 1.4462) — Cr 22 / Ni 5 / Mo 3 / N 0.16 austenitic + ferritic 50/50; UTS 620 MPa, YS 450 MPa, PREN ~35; subsea Christmas-tree manifolds, offshore platforms (Statoil Snøhvit), pulp + paper digesters.
  • Superduplex 2507 (UNS S32750, EN 1.4410) — Cr 25 / Ni 7 / Mo 4 / N 0.27; PREN ~42; deepwater oil + gas, FGD scrubbers; producers Outokumpu (Avesta SE), Sandvik, Acerinox, NSSC.
  • AL-6XN (UNS N08367) — Cr 21 / Ni 24 / Mo 6.5 / N 0.22 superaustenitic; PREN ~47; chloride + seawater service; nuclear-power condenser tubing replacing 90/10 CuNi where biofouling control is needed.

7.4 Steel-mill producers (global)

  • China Baowu Steel Group — largest globally, ~131 Mt crude steel 2023.
  • ArcelorMittal — global #2, Luxembourg HQ.
  • Nippon Steel — Japan, acquired US Steel announced 2023 (regulatory approval 2025).
  • POSCO — South Korea, Pohang + Gwangyang integrated mills.
  • JFE Steel — Japan.
  • Hyundai Steel — Korea.
  • Tata Steel — India (largest) + Europe (Port Talbot UK + IJmuiden NL).
  • Cleveland-Cliffs — US integrated (Burns Harbor, AK Steel acquisition 2020).
  • Nucor — US largest by capacity (mini-mill EAF).
  • U.S. Steel — US, Mon Valley + Gary Works.
  • Voestalpine — Austria, specialty + rail + automotive sheet; Donawitz + Linz.
  • BÖHLER-Uddeholm (Voestalpine subsidiary) — premium tool + high-speed + bearing + plastic-mold steel.
  • Carpenter Technology — US specialty alloys + powder (PA).
  • Universal Stainless — US specialty bar + billet.
  • ATI — US specialty (titanium, nickel, stainless).

8. Copper alloys (highlights — full catalog in Engineering Tier 3)

  • C36000 free-machining brass (UNS C36000) — Cu 61.5 / Zn 35.5 / Pb 3; UTS 380 MPa; screw-machine parts, plumbing fittings, ammunition.
  • C932 bearing bronze (UNS C93200, SAE 660) — Cu 83 / Sn 7 / Pb 7 / Zn 3; UTS 240 MPa; oil-impregnated sleeve bearings, bushings, wear plates.
  • C70600 CuNi 90/10 (UNS C70600) — Cu 88 / Ni 10 / Fe 1.4 / Mn 1; UTS 275 MPa; saltwater seawater piping (US Navy MIL-T-16420), condenser tubing, desalination plants.
  • C71500 CuNi 70/30 (UNS C71500) — Cu 69 / Ni 30; harder service, naval condensers + offshore.
  • C17200 beryllium-copper (UNS C17200) — Cu 98 / Be 1.9 / Co 0.25; UTS 1310 MPa age-hardened, hardness 41 HRC, non-sparking + non-magnetic; oilfield wrenches + drilling-rig hand tools, semiconductor probe pins, undersea cable connectors. Bechtel + Materion (parent), Be inhalation health-and-safety driven OSHA permissible exposure 0.2 µg/m³ (2019).
  • C18700 Cu-Ni-Si Corson (UNS C18700) — Cu 96.7 / Ni 2 / Si 0.5 precipitation hardened; UTS 750 MPa; lead-frames + automotive connectors replacing C17200 because Be-free.
  • GlidCop AL-15 / AL-25 / AL-60 (Hoganas, North American Höganäs) — Cu + 0.15-0.6% Al2O3 oxide dispersion strengthened (ODS); recrystallization to 900°C; spot-welding electrodes, X-ray-target backing, particle-accelerator-target backing (CERN, LCLS-II SLAC).

9. Lead, tin, zinc, magnesium specialty alloys

  • Eutectic Sn-Pb solder Sn63Pb37 — melting point 183°C; banned in EU under RoHS Directive 2002/95/EC effective 2006 for new consumer electronics. Replaced by SAC305 (Sn 96.5 / Ag 3 / Cu 0.5) m.p. 217°C, SAC405, SAC0307; military + medical + aerospace retain Sn-Pb under RoHS exemptions.
  • Pb-Sb-Sn babbitt (ASTM B23 Grade 2) — Pb 75 / Sb 15 / Sn 10; sleeve bearings for large rotating equipment (steam turbines, marine main shafts). Tin-base alternative Grade 1.
  • Pb-Sb 4-6% battery alloy — lead-acid battery grids; Antimony added for casting + creep resistance; Ca-Sn alternative grids in maintenance-free SLA batteries.
  • Magnesium AZ31B (UNS M11311) — Mg-Al 3 / Zn 1; sheet + extrusion; UTS 260 MPa, YS 200 MPa, density 1.77 g/cm³; phone cases, laptop chassis (Dell Latitude / HP EliteBook / Lenovo ThinkPad T-series).
  • AZ91D (UNS M11916) — Mg-Al 9 / Zn 1 / Mn 0.2; die casting standard; transmission cases (VW DSG, BMW B58), instrument panels, steering wheel armatures. World’s largest die-cast Mg producers: Magna, Meridian Lightweight Technologies, Georg Fischer Lightweight Castings.
  • WE43 (UNS M18430) — Mg-Y 4 / Nd 2.25 / Zr 0.5 / Mn 0.15 (rare-earth strengthened); UTS 270 MPa, creep resistance to 250°C; helicopter gearbox housings (Bell + Sikorsky + Boeing AH-64 transmission), CompositeShield armor; bioresorbable cardiovascular stents — Biotronik Magmaris (CE mark 2016, withdrawn from market for second-gen revision 2021).
  • ZK60 (UNS M16600) — Mg-Zn 5.5 / Zr 0.5; high-strength wrought; UTS 365 MPa; aerospace + sporting goods.
  • ME20 (UK) — Mg-Mn 1.5 / Ce 0.15; weldable.
  • Elektron 21 (Magnesium Elektron / Luxfer MEL Technologies UK) — Mg-Nd-Gd-Zn-Zr; aerospace transmission castings, motorsport.
  • ZAMAK 3 / 5 / 7 (UNS Z33520 / Z35540 / Z33523) — Zn-Al 4-Cu 1-Mg 0.04 family; die casting (HPDC) for hardware (Stanley Black & Decker, Master Lock), auto trim, plumbing handles.
  • ZA-8 / ZA-12 / ZA-27 (UNS Z35636 / Z35631 / Z35841) — high-Al (8-27%) Zn alloys; gravity + sand cast; mech-eng bushings + bearings; UTS up to 425 MPa (ZA-27).

10. Specialty + emerging metallic systems

  • Amorphous metals (metallic glasses) — Klement-Willens-Duwez 1960 quenched first Au-Si glass at ~10^6 K/s. Bulk metallic glasses (BMGs) need lower critical cooling rate.
    • Metglas 2605SA1 (Fe78B13Si9) — distribution transformer cores; magnetostriction λs ~12 ppm, saturation 1.56 T; ABB + Hitachi Metals (Proterial).
    • Vitreloy 1 (LiquidMetal — Caltech, Johnson 1992; Zr 41.2 / Ti 13.8 / Cu 12.5 / Ni 10 / Be 22.5) — first BMG cast in mm-thick sections; YS 1900 MPa, E 95 GPa, elastic strain limit ~2%; high-end golf clubs (Liquidmetal Technologies), surgical scalpels, watch springs (Omega Co-Axial escapement components), iPhone SIM ejection pin and other Apple structural parts under license to Eontec / Engel.
  • High-entropy alloys (HEAs) — independently published Yeh (NTHU 2004) + Cantor (Oxford 2004).
    • Cantor alloy Co20Cr20Fe20Mn20Ni20 — single-phase FCC; UTS 750 MPa, KIC 217 MPa·m^0.5 at 77 K (Otto + George 2014); cryogenic tank candidate.
    • AlCoCrFeNi — duplex FCC + BCC + ordered B2; tunable hardness 200-700 HV via Al content.
    • MoNbTaW Senkov refractory HEA — BCC; UTS 405 MPa @ 1600°C; turbine-blade candidate but oxidation problem unresolved.
    • CoCrFeNi (4-element) — Mn-free for fab cleanliness; cryogenic tankage research.
  • Bulk metallic glasses (Vitreloy 1 above) — Zr-Ti-Cu-Ni-Be family.
  • Shape-memory alloys:
    • Nitinol (NiTi 50:50 atomic, UNS N01555) — austenite-martensite reversible transformation between B2 (austenite, parent) and B19′ (martensite, monoclinic); Mf -50 to +80°C tunable. Pseudoelastic strain to 8%. Inventor William Buehler at Naval Ordnance Laboratory 1959 (Nitinol = “Nickel Titanium Naval Ordnance Laboratory”).
      • Applications: self-expanding peripheral + carotid + biliary + esophageal stents (Boston Scientific, Cook Medical, Medtronic, Abbott); orthodontic archwires (3M Unitek, Ormco); guidewires (Terumo, Asahi Intecc); JPL Mars 2020 Perseverance + Curiosity rover wheel SLEW shape-memory springs.
  • Auxetic + mechanical metamaterials — negative-Poisson honeycomb + chiral structures, foam-converted PU + PE auxetics; HRL Microlattice ultralight nickel “world’s lightest material 0.9 mg/cm³”; 3D-printed lattices at Lawrence Livermore + Carbon CLIP.

11. Manufacturing routes by alloy family

11.1 Vacuum melting (aerospace nickel + titanium)

  • VIM Vacuum Induction Melting — primary melting in vacuum to deoxidize + remove low-vapor-pressure tramp elements (Pb, Bi, Sb, Te). Special Metals + ATI + Haynes + Carpenter operate VIM. Ingot scale 1-30 t.
  • VAR Vacuum Arc Remelting — secondary remelt of consumable VIM ingot under vacuum; reduces macrosegregation; double-VAR required for rotating critical Ni superalloy per AMS 5663 / 2280.
  • ESR Electroslag Remelting — under molten CaF2 + CaO + Al2O3 slag; competitive with VAR for some grades (Ti, stainless); produces fine equiaxed structure.
  • Triple-melt (VIM-ESR-VAR) — largest critical forging ingots (Trent fan + IP turbine discs; 787 main landing gear forgings); the only route certified for some Boeing + Airbus + GE + RR rotating parts.

11.2 Powder atomization + HIP

  • Gas atomization (Ar inert, EIGA Electrode Induction-melting Gas Atomization for reactive Ti + Zr) at ATI Powermet + Carpenter Technology Powder Products + Praxair Surface Technologies + AP&C (GE Additive) + LPW + Tekna.
  • Hot Isostatic Pressing (HIP) at 1100-1280°C, 100-200 MPa Ar — consolidates powder to >99.9% density; PM-HIP grades like Udimet 720Li + Rene 88DT + Rene 104 (ME3) reach finer grain than wrought equivalents.
  • PM-HIP-net-shape for complex turbine + auxiliary turbine + valve bodies; Bodycote + Quintus + EPSI press supplied isostatic equipment.

11.3 Investment casting (turbine blades + vanes)

  • Lost-wax with ceramic shell. Equiaxed (EQ) → directionally solidified (DS, ~1970s, Bridgman furnace, Pratt & Whitney + GE) → single-crystal (SX, ~1980s, helical grain selector + seed) progression raises rupture life by ~40°C per generation.
  • Industry leaders: Howmet Aerospace (LaPorte IN, Whitehall MI, Exeter UK — formerly Pratt & Whitney Cast Parts, then Wyman-Gordon, then Alcoa, then Arconic spin-off); PCC Precision Castparts (PCC Aerostructures, Portland OR — Berkshire Hathaway subsidiary 2016); Doncasters Group UK; GE Aviation in-house casting Auburn AL; Rolls-Royce internal foundry Bristol + Indianapolis; RTX/Pratt & Whitney PW Power Systems Manufacturing.
  • 3D-printed ceramic core + wax for cooled blades — Voxeljet + 3D Systems + Howmet AM (Niskayuna).

11.4 Additive manufacturing — alloy / machine map

  • LPBF Laser Powder Bed Fusion — most-deployed metal AM:
    • EOS (Krailling DE) — M290, M300-4, M400-4. Qualified for IN718, IN625, Ti-6Al-4V Grade 5+23, AlSi10Mg, Scalmalloy, CoCrMo F75, MaragingMS1 (Maraging 300), 17-4PH, 316L, CuCrZr (rocket engine combustion chambers), HX, Cu pure, Mo, W.
    • SLM Solutions / Nikon SLM — NXG XII 600 (12 lasers); same alloy set + DDM-AM rocket combustors.
    • Renishaw — RenAM 500Q (UK).
    • GE Additive Concept Laser — M2 Series 5 (acquired Arcam 2016) + Concept Laser X Line 2000R big-box (800x400x500 mm).
    • Velo3D Sapphire / Sapphire XC — support-free overhang printing (0° vertical wall); SpaceX Crew Dragon SuperDraco + Aeon 1 (Relativity) + Rutherford (RocketLab).
    • Aconity — AconityMIDI / AconityONE.
    • Trumpf — TruPrint 3000 / 5000.
    • 3D Systems DMP Flex 350.
  • EBPBF Electron Beam Powder Bed Fusion — Arcam (GE Additive) Q20+ / Spectra H. Mostly Ti-6Al-4V + Ti-Al gamma-TiAl (RR / P&W LP turbine blades for GEnx + GE9X — TiAl 4822 first commercial use); CoCrMo orthopedic.
  • DED Directed Energy Deposition — laser + wire (Optomec LENS, Trumpf TruLaser Cell, BeAM, MeltioM450); electron beam wire (Sciaky EBAM — Lockheed Martin large titanium aerospace landing gear); plasma transferred arc (Norsk Titanium Merke IV — Boeing 787 titanium structural).
  • Binder Jetting — Desktop Metal Production System P-1/P-50, ExOne (acquired Desktop Metal 2021) X1 160Pro / X1 25Pro / Innovent+. Stainless 316L/17-4PH/4140/M2/Cu/Inconel 625/H13 currently; lower density (95-98% as-printed → ~99% after sintering + HIP).
  • WAAM Wire Arc Additive Manufacturing — Sciaky EBAM, Norsk Titanium Merke IV (titanium aerospace + production Boeing parts), Cranfield WAAM, Gefertec (Berlin, arc-3D), MX3D (Amsterdam — bridge demonstration).
  • Standards: ASTM F2924 Ti-6Al-4V LPBF, ASTM F3055 Inconel 718 LPBF, ASTM F3056 Inconel 625, ASTM F3184 17-4PH, ASTM F3318 AlSi10Mg.

11.5 Forging + rolling

  • Open-die forging — large discs, generator shafts, marine main shafts; press capacity 50 000+ tonnes at Aubert+Duval (Pamiers FR), Lechler (DE), Sumitomo Heavy Industries (JP), Western Superconducting Technologies (CN), Doosan (KR).
  • Closed-die forging — turbine discs + airframe bulkheads at ATI Forged Products, Howmet Aerospace, Aubert+Duval, Doncasters, Western Superconducting Technologies (CN — single-source for many ChAFTE forgings); F-35 aft fuselage bulkhead 7050-T7452 forging at Alcoa now Howmet.
  • Hot rolling — strip + plate at integrated mills (Cleveland-Cliffs, ArcelorMittal, Nippon Steel, POSCO, JFE, China Baowu); Nucor EAF flat-rolled (Indiana, Mississippi, AR).
  • Cold rolling — sheet to gauge; Outokumpu Avesta, Acerinox, Aperam stainless.
  • Ring rolling — bearing races, jet-engine casings; Forged Solutions / Doncasters / FUCHS.

12. Standards bodies + specifications

  • AMS Aerospace Material Specifications — published by SAE International; alloy + heat-treatment + processing. Numbered AMS 49xx (aluminum), AMS 56xx (steel), AMS 57xx (stainless + heat-resistant), AMS 65xx (titanium), AMS 77xx (Ni alloys).
  • MIL-DTL / MIL-STD — US Department of Defense; MIL-DTL-9046 Ti sheet, MIL-S-16216 HY-80, MIL-PRF-23377 epoxy primer.
  • ASTM International — ASTM A276 wrought stainless bar, A479 nuclear stainless, B164 Monel + Ni-Cu, B265 Ti sheet + plate, B348 Ti bar, B637 PH-stainless aerospace fasteners, F75 cast CoCrMo for surgical implants, F136 Ti-6Al-4V ELI for surgical, F899 stainless surgical instruments, F1295 Ti-Nb biomedical, F1537 wrought CoCrMo, F2924 LPBF Ti-6Al-4V, F3055 LPBF IN718.
  • UNS Unified Numbering System (SAE + ASTM joint) — S31600 = 316SS, R56400 = Ti-6Al-4V, N07718 = Inconel 718, N06600 = Inconel 600, A92024 = 2024 Al, M11311 = AZ31B, C36000 = Brass 360.
  • ISO — ISO 5832-1 (Ti implants), ISO 5832-9 (Ti-Nb biomedical), ISO 6892-1 (tensile testing).
  • JIS Japan Industrial Standards — JIS G 4304 (stainless plate), JIS H 4600 (Ti plate).
  • DIN / EN German + European — DIN 17440 stainless (superseded by EN 10088), EN 10025 structural, EN AW 2024 aluminum.
  • GB Chinese national — GB/T 3280 stainless, GB/T 3620 Ti alloys.

Safety-critical traceability mandates double + triple lot certification, mechanical-test bars per heat, micrograph + chemistry per lot.

Adjacent

Graph View