# Hangbo Alloy — full grade data dump
# Generated 2026-09-20. Values are typical or standard specification limits.
# Source: https://www.hb-nickelalloy.com/llms-full.txt

## Duplex Stainless Steel 2205 (UNS S32205)
URL: https://www.hb-nickelalloy.com/alloys/stainless-2205/
Family: Stainless Steel
Equivalents: DIN 1.4462; GB 022Cr22Ni5Mo3N
2205 duplex stainless (UNS S32205) has a roughly equal ferrite/austenite structure. Yield strength is about twice that of 316L and PREN is around 35, with excellent chloride stress-corrosion-cracking and pitting resistance, making it a mainstay for marine, chemical and oil and gas service.
Composition (wt%): Fe Balance; Cr 22.0–23.0; Ni 4.50–6.50; Mo 3.00–3.50; N 0.14–0.20; Mn ≤ 2.00; Si ≤ 1.00; C ≤ 0.030
Mechanical (RT): tensile ≥ 620 MPa; yield ≥ 450 MPa; elongation ≥ 25 %; hardness ≤ 293 HB
Physical: density 7.80 g/cm³; melting 1385–1443 °C; thermal conductivity 19.0 W/m·K; modulus 190 GPa; max service 300 °C
Standards: ASTM A276; ASTM A240; ASTM A790; ASTM A182; UNS S32205
Applications: Offshore platforms and subsea pipelines; Chemical vessels and heat exchangers; Oil and gas transport and sour gas piping; Desalination and effluent treatment; Pulp digesters and bleaching equipment
Q: What is the service temperature limit of 2205 duplex?
A: 2205 is generally limited to −50 to 300 °C. Long-term exposure between 300 and 525 °C precipitates sigma phase, sharply reducing toughness and corrosion resistance, while below −50 °C the ferrite phase risks ductile-to-brittle transition. For high-temperature service use 316H, 800H or a nickel alloy.
Q: How do I choose between 2205 and 2507 super duplex?
A: 2507 (S32750) contains 25% Cr, 4% Mo and 0.27% N with PREN around 40–42 and yield near 550 MPa — better corrosion resistance and strength than 2205 at roughly 30–50% higher price. Choose 2507 for high chloride, higher temperature or extended-life service; 2205 is adequate for normal seawater and chemical duties.

## GH2132 (A-286) (UNS S66286)
URL: https://www.hb-nickelalloy.com/alloys/gh2132/
Family: High-Temperature Alloys / Superalloys
Equivalents: DIN 1.4980; GB GH2132
GH2132 is an iron-nickel-chromium precipitation-hardening superalloy (equivalent to A-286). Below 650 °C it offers high yield strength and creep resistance with good oxidation resistance at moderate cost, making it the principal Chinese grade for aero-engine and gas-turbine fasteners and discs.
Composition (wt%): Fe Balance; Ni 24.0–27.0; Cr 13.5–16.0; Ti 1.75–2.30; Mo 1.00–1.50; V 0.10–0.50; Al ≤ 0.40; B 0.001–0.010; C ≤ 0.08
Mechanical (RT): tensile ≥ 930 MPa (aged); yield ≥ 660 MPa (aged); elongation ≥ 15 %; hardness ≥ 28 HRC
Physical: density 7.93 g/cm³; melting 1364–1424 °C; thermal conductivity 15.1 W/m·K; modulus 201 GPa; max service 650 °C
Standards: GB/T 14992; GB/T 14994; GJB 3165; AMS 5731
Applications: Aero-engine discs, blades and fasteners; Gas turbine high-temperature bolting and springs; Automotive turbocharger wheels and exhaust parts; High-temperature petrochemical equipment
Q: How do I choose between GH2132 and GH4169 (Inconel 718)?
A: GH2132 is iron-base with good strength below 650 °C at roughly 50–60% of GH4169's cost. GH4169 is nickel-base with higher strength below 650 °C, better weldability and fatigue resistance, and excellent cryogenic toughness. Choose GH4169 for highly stressed, long-life or welded critical parts, and GH2132 for volume fasteners and mid-temperature components where economy matters.

## GH2747 (Haynes 747) (UNS —)
URL: https://www.hb-nickelalloy.com/alloys/gh2747/
Family: High-Temperature Alloys / Superalloys
Equivalents: DIN —; GB GH2747
GH2747 is a Fe-Ni-Cr precipitation-hardening superalloy (equivalent to US Haynes 747 and Russian ЭП747). High chromium, high aluminium and rare-earth cerium give outstanding oxidation resistance at 1100–1250 °C (short-term to 1300 °C) at lower cost than nickel-base grades, for furnace rollers, thermocouple sheaths and heat-treatment equipment parts.
Composition (wt%): Fe Balance; Ni 44.0–46.0; Cr 15.0–17.0; Al 2.9–3.9; Ce ≤ 0.03; C ≤ 0.10; Si ≤ 1.0; Mn ≤ 1.0
Mechanical (RT): tensile ≥ 735 MPa; yield ≥ 400 MPa; elongation ≥ 18 %; hardness ≤ 250 HB
Physical: density 8.0 g/cm³; melting 1300–1410 °C; thermal conductivity 14.0 W/m·K; modulus 205 GPa; max service 1100–1250 °C
Standards: GB/T 14992
Applications: Furnace rollers, radiant tubes and trays; Thermocouple sheaths and heat-resistant parts; Ethylene cracking furnace internals; Glass and ceramic kiln components
Q: What service temperature does GH2747 reach?
A: GH2747 serves long-term to 1100–1250 °C and short-term to 1300 °C. It is supplied in the solution-treated condition; to raise mid-temperature strength of 700–900 °C, age at 750–800 °C for 16 h and air cool.

## GH3030 (ЭИ435) (UNS —)
URL: https://www.hb-nickelalloy.com/alloys/gh3030/
Family: High-Temperature Alloys / Superalloys
Equivalents: DIN 2.4951; GB GH3030
GH3030 is an 80Ni-20Cr solid-solution nickel superalloy with good oxidation resistance and hot strength below 800 °C. Easy to hot/cold work and weld, it is a classic material for aero-engine combustors and afterburner components.
Composition (wt%): Ni Balance; Cr 19.0–22.0; Fe ≤ 1.5; Ti 0.15–0.35; Al ≤ 0.15; C ≤ 0.12; Mn ≤ 0.70; Si ≤ 0.80; S ≤ 0.020
Mechanical (RT): tensile ≥ 685 MPa; yield ≥ 295 MPa; elongation ≥ 30 %; hardness ≤ 190 HB
Physical: density 8.40 g/cm³; melting 1374–1420 °C; thermal conductivity 15.1 W/m·K; modulus 212 GPa; max service 1000 °C
Standards: GB/T 14992; GB/T 14994; GJB 3165
Applications: Aero-engine combustors, afterburners and flame tubes; Turbine guide vanes operating below 800 °C; Industrial gas turbine hot parts; Heat-treat furnace components
Q: What heat treatment does GH3030 use?
A: GH3030 is normally solution treated at 980–1020 °C and air or water cooled. For cold-rolled sheet, annealing at 1050–1080 °C gives a fine grain and good formability. The alloy cannot be age hardened — properties are adjusted only by solution treatment and cold work.

## GH3039 (ЭИ602) (UNS —)
URL: https://www.hb-nickelalloy.com/alloys/gh3039/
Family: High-Temperature Alloys / Superalloys
Equivalents: DIN —; GB GH3039
GH3039 is a Ni-Cr solid-solution nickel superalloy with good oxidation resistance and hot strength below 800 °C. Easy to hot/cold work and weld, it is a widely used Chinese grade for aero-engine combustors, flame tubes and chemical high-temperature parts.
Composition (wt%): Ni Balance; Cr 19.0–22.0; Mo 1.80–2.30; Al 0.35–0.75; Ti 0.35–0.75; Nb 0.90–1.30; Fe ≤ 3.0; C ≤ 0.08
Mechanical (RT): tensile ≥ 735 MPa; yield ≥ 345 MPa; elongation ≥ 30 %; hardness ≤ 200 HB
Physical: density 8.30 g/cm³; melting 1330–1380 °C; thermal conductivity 21.8 W/m·K; modulus 205 GPa; max service 800 °C
Standards: GB/T 14992; GB/T 14994; GJB 3165
Applications: Aero-engine combustors and flame tubes; Afterburners and exhaust nozzle parts; Heat-treatment furnaces and chemical high-temperature parts; Gas turbine hot sheet components
Q: What heat treatment does GH3039 use?
A: GH3039 is normally solution treated at 1050–1080 °C and air or water cooled. It is solid-solution strengthened and cannot be age hardened — properties are adjusted by solution treatment and cold work.

## GH3044 (ЭИ868) (UNS —)
URL: https://www.hb-nickelalloy.com/alloys/gh3044/
Family: High-Temperature Alloys / Superalloys
Equivalents: DIN —; GB GH3044
GH3044 is a high-tungsten solid-solution nickel superalloy. With a high tungsten content it offers good plasticity, moderate hot strength below 900 °C and excellent oxidation resistance together with outstanding stamping and welding behaviour, used for combustion chambers and afterburner sheet structures.
Composition (wt%): Ni Balance; Cr 23.5–26.5; W 13.0–16.0; Mo ≤ 1.50; Al ≤ 0.50; Ti 0.30–0.70; Fe ≤ 4.0; C ≤ 0.10
Mechanical (RT): tensile ≥ 685 MPa; yield ≥ 345 MPa; elongation ≥ 30 %; hardness ≤ 250 HB
Physical: density 8.89 g/cm³; melting 1320–1370 °C; thermal conductivity 12.7 W/m·K; modulus 210 GPa; max service 900 °C
Standards: GB/T 14992; GB/T 14994; GJB 3165
Applications: Aero-engine combustors and afterburners; Gas turbine hot sheet components; Flame tubes and heat shields; Heat-treatment furnace components
Q: Why does GH3044 contain so much tungsten?
A: The 13.0–16.0% tungsten provides solid-solution strengthening, keeping high hot strength and creep resistance below 900 °C while retaining good plasticity and workability.

## GH4080A (Nimonic 80A) (UNS N07080)
URL: https://www.hb-nickelalloy.com/alloys/gh4080a/
Family: High-Temperature Alloys / Superalloys
Equivalents: DIN 2.4952; GB GH4080A
GH4080A is a Ni-Cr base precipitation-hardening superalloy (equivalent to British Nimonic 80A), strengthened by γ′ (Ni₃(Al,Ti)). It offers good creep and oxidation resistance below 800 °C with good hot/cold workability and a low cobalt content for cost control, for turbine blades, discs, high-temperature bolts and springs.
Composition (wt%): Ni Balance; Cr 18.0–21.0; Co ≤ 2.0; Al 1.0–1.8; Ti 1.8–2.7; Mo 1.0–1.8; Fe ≤ 1.5; C 0.04–0.10; B ≤ 0.008
Mechanical (RT): tensile ≥ 1000 MPa; yield ≥ 600 MPa; elongation ≥ 20 %; hardness ≥ 285 HB
Physical: density 8.15 g/cm³; melting 1395–1425 °C; thermal conductivity 11.3 W/m·K; modulus 214 GPa; max service 800 °C
Standards: GB/T 14992; ASTM B637; HB 5286
Applications: Gas-turbine blades and discs; High-temperature bolts, fasteners and springs; Diesel-engine exhaust valves; Nuclear and marine high-temperature load-bearing parts
Q: What is the standard heat treatment for GH4080A?
A: Solution treatment at 1080 °C ±10 °C for 8 h followed by oil or water cooling, then ageing at 700 °C ±10 °C for 16 h and air cooling.

## GH4090 (Nimonic 90) (UNS N07090)
URL: https://www.hb-nickelalloy.com/alloys/gh4090/
Family: High-Temperature Alloys / Superalloys
Equivalents: DIN 2.4632; GB GH4090
GH4090 is a Ni-Cr-Co precipitation-hardening superalloy (equivalent to British Nimonic 90). It offers high tensile and creep resistance at 815–870 °C with good oxidation and corrosion resistance and high fatigue strength under thermal cycling, for turbine blades, discs, high-temperature fasteners and springs.
Composition (wt%): Ni Balance; Cr 18.0–21.0; Co 15.0–21.0; Ti 2.0–3.0; Al 1.0–2.0; Fe ≤ 1.5; C ≤ 0.13; Si ≤ 1.0; Mn ≤ 1.0
Mechanical (RT): tensile ≥ 1080 MPa; yield ≥ 690 MPa; elongation ≥ 15 %; hardness 28–35 HRC
Physical: density 8.18 g/cm³; melting 1310–1370 °C; thermal conductivity 11.5 W/m·K; modulus 210 GPa; max service 920 °C
Standards: GB/T 14992; ASTM B637; AMS 5829
Applications: Gas turbine blades and discs; High-temperature fasteners, clamps and seals; Exhaust valves and springs; Compressor and hot-section load-bearing parts
Q: What is the typical heat treatment for GH4090?
A: Solution treatment at about 1080 °C for 8 h followed by air/oil cooling, then ageing at 700–720 °C for 16 h and air cooling.

## GH4099 (ЭП693) (UNS —)
URL: https://www.hb-nickelalloy.com/alloys/gh4099/
Family: High-Temperature Alloys / Superalloys
Equivalents: DIN —; GB GH4099
GH4099 is a Ni-Cr-Co-W-Mo precipitation-hardened nickel superalloy for long-term service at 900 °C and short-term at 1000 °C. Combining high-temperature strength with excellent oxidation resistance and weldability, it is the material of choice for aero-engine combustor and afterburner welded load-bearing sheet structures.
Composition (wt%): Ni Balance; Cr 17.0–20.0; Co 5.0–8.0; W 5.0–7.0; Mo 3.5–4.5; Al 1.7–2.4; Ti 1.0–1.5; Fe ≤ 2.0; C ≤ 0.08
Mechanical (RT): tensile ≥ 1100 MPa; yield ≥ 700 MPa; elongation ≥ 12 %; hardness 280–320 HBW
Physical: density 8.30 g/cm³; melting 1330–1390 °C; thermal conductivity 21.8 W/m·K; modulus 208 GPa; max service 900 °C
Standards: GB/T 14992; GB/T 14995; GJB 1952A
Applications: Aero-engine combustors and afterburners; High-temperature welded load-bearing sheet structures; Gas turbine hot components; Aero-engine heat-affected structures
Q: What is the heat treatment for GH4099?
A: Solution treatment at 1080–1140 °C (1140–1160 °C for sheet) followed by air cooling; to raise strength between 600–900 °C, age at 900 °C ±10 °C for 4 h and air cool. Large welded sheet assemblies can be used directly after solution treatment.

## GH4648 (ЭП648) (UNS —)
URL: https://www.hb-nickelalloy.com/alloys/gh4648/
Family: High-Temperature Alloys / Superalloys
Equivalents: DIN —; GB GH4648
GH4648 is a very-high-chromium (about 32%) nickel-base precipitation-hardening superalloy for long-term service at 900 °C and short-term to 1100 °C, offering outstanding oxidation and hot-corrosion resistance with moderate strength and good fatigue/creep behaviour, for high-temperature structural parts in corrosive service.
Composition (wt%): Ni Balance; Cr 32.0–35.0; W 4.5–5.5; Mo 2.5–3.5; Al 0.5–1.1; Ti 0.5–1.1; Nb 0.5–1.1; Fe ≤ 4.0; C ≤ 0.10
Mechanical (RT): tensile ≥ 780 MPa; yield ≥ 345 MPa; elongation ≥ 25 %; hardness 220–280 HBW
Physical: density 8.27 g/cm³; melting 1336–1395 °C; thermal conductivity 11.2 W/m·K; modulus 205 GPa; max service 900 °C
Standards: GB/T 14992
Applications: Aero-engine combustor casings and flame tubes; Turbine guide vanes and exhaust nozzle flaps; Ethylene cracking furnace tubes; Gas turbine combustor liners
Q: Are there any usage cautions for GH4648?
A: Avoid long-term service in the 550–650 °C sensitisation range where grain-boundary carbide coarsening may reduce impact toughness; in sulphur-bearing gas above 800 °C keep sulphur below 0.1% to prevent hot sulphidation.

## GH4708 (ЭП742) (UNS —)
URL: https://www.hb-nickelalloy.com/alloys/gh4708/
Family: High-Temperature Alloys / Superalloys
Equivalents: DIN —; GB GH4708
GH4708 is a Ni-Cr-Co base superalloy strengthened by W/Mo solid-solution and Al/Ti γ′ precipitation, giving high strength, oxidation resistance and thermal-fatigue resistance, for turbine discs, blades and fasteners in aero-engines and industrial gas turbines.
Composition (wt%): Ni Balance; Cr 17.0–20.0; Co 12.0–15.0; W 5.5–7.0; Mo 3.5–5.0; Al 1.0–1.8; Ti 2.5–3.5; Fe ≤ 4.0; C 0.05–0.10
Mechanical (RT): tensile ≥ 1275 MPa; yield ≥ 835 MPa; elongation ≥ 12 %; hardness 320–380 HBW
Physical: density 8.35 g/cm³; melting 1320–1360 °C; thermal conductivity 11.0 W/m·K; modulus 210 GPa; max service 800 °C
Standards: GB/T 14992
Applications: Turbine discs, blades and high-temperature fasteners; Gas-turbine rotors and load-bearing shafts; Aero-engine hot-section parts; Compressor and turbine high-temperature components
Q: What is the heat treatment for GH4708?
A: GH4708 uses a standard three-step treatment: solution at 1120 °C ±10 °C for 2–4 h followed by air cooling, then staged ageing to precipitate fine γ′ for optimum combined properties.

## GH4738 (Waspaloy) (UNS N07001)
URL: https://www.hb-nickelalloy.com/alloys/gh4738/
Family: High-Temperature Alloys / Superalloys
Equivalents: DIN 2.4654; GB GH4738
GH4738 is a Ni-Cr-Co base precipitation-hardening superalloy (equivalent to US Waspaloy), strengthened by γ′. It offers high tensile and creep strength up to about 760 °C with good oxidation resistance, and is the standard material for turbine discs, blades and high-stress fasteners in aero and industrial gas turbines.
Composition (wt%): Ni Balance; Cr 18.0–21.0; Co 12.0–15.0; Mo 3.5–5.0; Ti 2.75–3.25; Al 1.20–1.60; Fe ≤ 2.0; C 0.02–0.10; Zr ≤ 0.10
Mechanical (RT): tensile ≥ 1200 MPa; yield ≥ 835 MPa; elongation ≥ 15 %; hardness 30–40 HRC
Physical: density 8.19 g/cm³; melting 1320–1360 °C; thermal conductivity 12.0 W/m·K; modulus 210 GPa; max service 760 °C
Standards: GB/T 14992; ASTM B637; AMS 5704
Applications: Gas-turbine discs and rings; Turbine and compressor blades; High-strength high-temperature fasteners; Gas-turbine rotors and load-bearing shafts
Q: How do I choose between GH4738 and GH4080A?
A: Both are γ′ precipitation-hardened nickel superalloys. GH4738 (Waspaloy) has a higher cobalt content (12–15%) and higher strength, serving to about 760 °C for highly stressed discs and blades; GH4080A has low cobalt (≤2%) with better cost control for mid-temperature bolts, springs and exhaust valves below 800 °C.

## Hastelloy B-2 (UNS N10665)
URL: https://www.hb-nickelalloy.com/alloys/hastelloy-b-2/
Family: Hastelloy Alloys
Equivalents: DIN 2.4617; GB NS3202
Hastelloy B-2 (UNS N10665) is a nickel-molybdenum alloy with 26–30% molybdenum, giving excellent resistance to reducing media such as hydrochloric and sulphuric acid. Low carbon and silicon keep the weldment free from intergranular attack, making it a specialist material for HCl and acetic acid plant.
Composition (wt%): Ni Balance; Mo 26.0–30.0; Fe ≤ 2.0; Cr ≤ 1.0; Co ≤ 1.00; C ≤ 0.02; Si ≤ 0.10; Mn ≤ 1.00; P ≤ 0.040; S ≤ 0.030
Mechanical (RT): tensile ≥ 760 MPa; yield ≥ 350 MPa; elongation ≥ 40 %; hardness ≤ 200 HB
Physical: density 9.22 g/cm³; melting 1330–1380 °C; thermal conductivity 11.0 W/m·K; modulus 217 GPa; max service 1000 °C
Standards: ASTM B335; ASTM B333; ASTM B622; ASTM B564; UNS N10665
Applications: Hydrochloric acid production, storage and transfer equipment; Acetic acid and acetic anhydride plant; Alkylation and catalyst recovery systems; Sulphuric acid recovery and concentration; Agrochemical and dye intermediate reactors
Q: Why can't Hastelloy B-2 be used in hydrochloric acid containing oxidising impurities?
A: B-2 relies on a molybdenum-rich film that is stable only in reducing environments. When Fe³⁺, Cu²⁺, dissolved oxygen or nitric acid are present, the corrosion potential shifts and the film breaks down, sharply increasing the corrosion rate. Switch to chromium-bearing C-22 or C-2000 in that case.
Q: What is the difference between B-2 and B-3?
A: B-3 (UNS N10675) has a tuned chemistry with small chromium addition and controlled iron, greatly improving thermal stability. It is far less prone than B-2 to precipitating Ni-Mo intermetallic phases during mid-temperature (600–800 °C) processing, so welding and hot forming are safer and properties more consistent. B-3 is preferred for new projects.

## Hastelloy B-3 (UNS N10675)
URL: https://www.hb-nickelalloy.com/alloys/hastelloy-b-3/
Family: Hastelloy Alloys
Equivalents: DIN 2.4600; GB NS3203
Hastelloy B-3 (UNS N10675) is the upgraded successor to B-2. It keeps excellent hydrochloric acid resistance while greatly improving thermal stability, resisting Ni₄Mo and other intermetallic precipitation during mid-temperature processing and welding, which widens the forming and welding window.
Composition (wt%): Ni ≥ 65.0; Mo 27.0–32.0; Cr 1.0–3.0; Fe 1.0–3.0; Co ≤ 3.00; W ≤ 3.0; C ≤ 0.01; Si ≤ 0.10; Mn ≤ 3.00
Mechanical (RT): tensile ≥ 760 MPa; yield ≥ 350 MPa; elongation ≥ 40 %; hardness ≤ 200 HB
Physical: density 9.22 g/cm³; melting 1370–1418 °C; thermal conductivity 11.0 W/m·K; modulus 216 GPa; max service 1000 °C
Standards: ASTM B335; ASTM B333; ASTM B622; ASTM B564; UNS N10675
Applications: HCl synthesis, absorption and concentration plant; Acetic acid and anhydride production; Sulphuric acid alkylation units; Catalyst recovery systems
Q: Why is B-3 recommended over B-2 for new hydrochloric acid equipment?
A: B-2 precipitates the ordered Ni₄Mo phase when held between 600 and 800 °C, reducing toughness and corrosion resistance. B-3's tuned chemistry delays this precipitation substantially, making rolling, head forming and multi-pass welding safer. For equipment requiring several hot-work passes, B-3 is the more reliable choice.

## Hastelloy C-2000 (UNS N06200)
URL: https://www.hb-nickelalloy.com/alloys/hastelloy-c-2000/
Family: Hastelloy Alloys
Equivalents: DIN 2.4675; GB —
Hastelloy C-2000 (UNS N06200) adds about 1.6% copper and raises chromium to 22–24% while keeping 16% molybdenum. It is the only C-family alloy that spans both oxidising acids (nitric) and reducing acids (sulphuric, hydrochloric), giving the widest universality.
Composition (wt%): Ni Balance; Cr 22.0–24.0; Mo 15.0–17.0; Cu 1.30–1.90; Fe ≤ 3.0; Co ≤ 2.00; C ≤ 0.010; Si ≤ 0.08; Mn ≤ 0.50
Mechanical (RT): tensile ≥ 690 MPa; yield ≥ 310 MPa; elongation ≥ 45 %; hardness ≤ 200 HB
Physical: density 8.50 g/cm³; melting 1320–1390 °C; thermal conductivity 9.9 W/m·K; modulus 206 GPa; max service 1040 °C
Standards: ASTM B574; ASTM B575; ASTM B622; ASTM B564; UNS N06200
Applications: Fine-chemical reactors with frequent product changes; Mixed-acid pickling and acid recovery; Hydrometallurgy with fluorides and sulphuric acid; Critical FGD and effluent treatment parts
Q: What service suits C-2000 best?
A: C-2000 suits processes where the medium changes frequently and one vessel must handle several acids — multi-product fine-chemical reactors, mixed-acid pickling lines and acid recovery units. If exposure is a single, stable medium, C-276 (reducing) or C-22 (oxidising) is usually more economical.

## Hastelloy C-22 (UNS N06022)
URL: https://www.hb-nickelalloy.com/alloys/hastelloy-c-22/
Family: Hastelloy Alloys
Equivalents: DIN 2.4602; GB NS3308
Hastelloy C-22 (UNS N06022) is one of the most oxidation-resistant grades in the Ni-Cr-Mo-W family with 20–22.5% chromium. It performs exceptionally in mixed oxidising/reducing acids, against localised corrosion and at elevated temperature, suiting processes where chemistry fluctuates.
Composition (wt%): Ni Balance; Cr 20.0–22.5; Mo 12.5–14.5; W 2.5–3.5; Fe 2.0–6.0; Co ≤ 2.50; V ≤ 0.35; C ≤ 0.015; Si ≤ 0.08; Mn ≤ 0.50
Mechanical (RT): tensile ≥ 690 MPa; yield ≥ 310 MPa; elongation ≥ 45 %; hardness ≤ 200 HB
Physical: density 8.69 g/cm³; melting 1357–1399 °C; thermal conductivity 10.1 W/m·K; modulus 206 GPa; max service 1035 °C
Standards: ASTM B574; ASTM B575; ASTM B622; ASTM B564; NACE MR0175 / ISO 15156; UNS N06022
Applications: FGD systems and flue-gas scrubbers; Mixed acid (nitric/hydrofluoric) pickling lines; Nuclear waste treatment and fuel reprocessing; Agrochemical and fine-chemical reactors; Pharmaceutical equipment and clean piping
Q: What is the PREN of Hastelloy C-22?
A: Using PREN = %Cr + 3.3×(%Mo + 0.5×%W) + 16×%N with Cr 21%, Mo 13% and W 3% gives roughly 21 + 3.3×14.5 ≈ 69. With the simplified formula, engineering values land around 64–69 — comfortably above Inconel 625 (about 51) and comparable to or slightly above C-276.

## Hastelloy C-276 (UNS N10276)
URL: https://www.hb-nickelalloy.com/alloys/hastelloy-c-276/
Family: Hastelloy Alloys
Equivalents: DIN 2.4819; GB NS3304 / 00Cr15Ni60Mo16W4
Hastelloy C-276 (UNS N10276) is the most widely used 'universal' corrosion resistant alloy in the Ni-Cr-Mo-W family. Its low carbon and silicon design prevents carbide and intermetallic precipitation in the weld heat-affected zone, so it handles mixed oxidising and reducing media, wet chlorine, hypochlorite and many mineral acids.
Composition (wt%): Ni Balance; Mo 15.0–17.0; Cr 14.5–16.5; Fe 4.0–7.0; W 3.0–4.5; Co ≤ 2.50; V ≤ 0.35; C ≤ 0.01; Si ≤ 0.08; Mn ≤ 1.00; P ≤ 0.040; S ≤ 0.030
Mechanical (RT): tensile ≥ 690 MPa; yield ≥ 283 MPa; elongation ≥ 40 %; hardness ≤ 200 HB
Physical: density 8.89 g/cm³; melting 1325–1370 °C; thermal conductivity 9.8 W/m·K; modulus 205 GPa; max service 1040 °C
Standards: ASTM B574; ASTM B575; ASTM B622; ASTM B564; NACE MR0175 / ISO 15156; UNS N10276
Applications: FGD absorbers and stack liners; Chemical reactors, heat exchangers and distillation columns; Pulp bleaching and chlorine dioxide generation; Sour (H₂S/CO₂) oil and gas production; Pharmaceutical and agrochemical synthesis plant; Waste incineration and effluent treatment
Q: How do I choose between Hastelloy C-276 and C-22?
A: C-22 (UNS N06022) has more chromium (20–22.5%), slightly less molybdenum and tungsten, giving better resistance and thermal stability in oxidising media and mixed acids with a marginally higher PREN. C-276 is more cost-effective in strong reducing acids such as hydrochloric acid and in chlorinated oxidising service. Choose C-22 when the medium swings oxidising or runs hot; choose C-276 when reducing acids dominate and cost matters.
Q: Does C-276 require post-weld heat treatment?
A: Normally not. With carbon ≤ 0.01% and silicon ≤ 0.08%, the heat-affected zone does not sensitise in the as-welded condition — the key improvement over earlier C-family alloys. A 1120 °C solution anneal and rapid quench is only considered for extremely aggressive media or where stress-corrosion risk from residual stress exists.
Q: Why is Hastelloy C-276 far more expensive than 316L?
A: It comes down to alloy content: C-276 carries about 16% molybdenum, 15.5% chromium and 3–4.5% tungsten, whereas 316L has only 2–3% molybdenum on an iron base. Molybdenum, nickel and tungsten cost far more than iron and chromium, and melting (usually VIM plus ESR) plus difficult hot working lowers yield, so unit price typically runs 8–15 times that of 316L.

## Hastelloy X (UNS N06002)
URL: https://www.hb-nickelalloy.com/alloys/hastelloy-x/
Family: Hastelloy Alloys
Equivalents: DIN 2.4665; GB GH3536 / GH22
Hastelloy X (UNS N06002) is a solid-solution Ni-Cr-Fe-Mo superalloy combining oxidation resistance to 1200 °C with useful high-temperature strength. It resists combustion-gas corrosion and thermal fatigue, making it a classic material for aero-engine combustors, afterburners and industrial furnaces.
Composition (wt%): Ni Balance; Cr 20.5–23.0; Fe 17.0–20.0; Mo 8.0–10.0; Co 0.50–2.50; W 0.20–1.00; C 0.05–0.15; Si ≤ 1.00; Mn ≤ 1.00; B ≤ 0.008
Mechanical (RT): tensile ≥ 655 MPa; yield ≥ 240 MPa; elongation ≥ 35 %; hardness ≤ 200 HB
Physical: density 8.22 g/cm³; melting 1260–1355 °C; thermal conductivity 9.1 W/m·K; modulus 205 GPa; max service 1200 °C
Standards: ASTM B572; ASTM B435; ASTM B622; AMS 5536; UNS N06002
Applications: Aero-engine combustors, afterburners and tailpipes; Industrial gas turbine transition ducts and flame tubes; Industrial furnace rollers, radiant tubes and muffles; Reformer and cracking furnace components; Heat-treat fixtures and baskets
Q: How does Hastelloy X differ from Inconel 601?
A: Both resist high-temperature oxidation, but X carries 8–10% molybdenum and 17–20% iron, giving markedly better hot strength and combustion-gas corrosion resistance plus oxidation resistance to 1200 °C. 601 costs less and is more cost-effective for furnace parts in clean air without combustion-gas attack.

## Incoloy 800 (UNS N08800)
URL: https://www.hb-nickelalloy.com/alloys/incoloy-800/
Family: Incoloy Alloys
Equivalents: DIN 1.4876; GB NS1101 / 0Cr20Ni32AlTi
Incoloy 800 (UNS N08800) is an iron-nickel-chromium heat-resistant alloy with 30–35% nickel and 19–23% chromium. It stays microstructurally stable and oxidation resistant at temperature while resisting nitric and organic acids, making it a cost-effective choice for heat exchangers and furnace tubing.
Composition (wt%): Ni 30.0–35.0; Cr 19.0–23.0; Fe ≥ 39.5; Al 0.15–0.60; Ti 0.15–0.60; Cu ≤ 0.75; C ≤ 0.10; Mn ≤ 1.50; Si ≤ 1.00
Mechanical (RT): tensile ≥ 520 MPa; yield ≥ 205 MPa; elongation ≥ 30 %; hardness ≤ 180 HB
Physical: density 7.94 g/cm³; melting 1357–1385 °C; thermal conductivity 11.5 W/m·K; modulus 196 GPa; max service 1100 °C
Standards: ASTM B408; ASTM B409; ASTM B163; ASTM B564; UNS N08800
Applications: Heat exchanger and evaporator tube bundles; Nitric acid and caprolactam plant; Steam superheaters and boiler tubes; Heat-treat furnace components
Q: What is the difference between 800, 800H and 800HT?
A: The chemistries are close; the difference is carbon content and heat treatment. 800 (C ≤ 0.10%) serves below 600 °C. 800H (C 0.05–0.10%) is solution annealed above 1120 °C to obtain a coarse grain (ASTM 5 or coarser) for improved creep strength up to about 815 °C. 800HT (C 0.06–0.10% with Al+Ti 0.85–1.20%) has a tighter composition and is solution treated for the highest creep-rupture strength, and is the standard choice for stressed components above 815 °C.

## Incoloy 800HT (UNS N08811)
URL: https://www.hb-nickelalloy.com/alloys/incoloy-800ht/
Family: Incoloy Alloys
Equivalents: DIN 1.4959; GB NS1103
Incoloy 800HT (UNS N08811) has the highest creep-rupture strength in the 800 series. By restricting Al+Ti to 0.85–1.20% and guaranteeing a coarse solution-annealed grain structure it performs best in long-term stressed service above 815 °C.
Composition (wt%): Ni 30.0–35.0; Cr 19.0–23.0; Fe ≥ 39.5; Al+Ti 0.85–1.20; C 0.06–0.10; Cu ≤ 0.75; Mn ≤ 1.50; Si ≤ 1.00
Mechanical (RT): tensile ≥ 450 MPa; yield ≥ 170 MPa; elongation ≥ 30 %; hardness ≤ 180 HB
Physical: density 7.94 g/cm³; melting 1357–1385 °C; thermal conductivity 11.5 W/m·K; modulus 196 GPa; max service 1100 °C
Standards: ASTM B408; ASTM B409; ASTM B407; ASTM B564; ASME SB-409; UNS N08811
Applications: Ethylene cracking furnace tubes and pigtails; Reformer manifolds and outlet headers; High-temperature nuclear heat exchangers; Heat-treat rollers and radiant tubes
Q: Why must 800HT keep Al+Ti between 0.85 and 1.20%?
A: Aluminium and titanium form the γ′ strengthening phase, but in 800HT's target range (above 815 °C) γ′ coarsens quickly and loses effect. Holding Al+Ti at 0.85–1.20% ensures strength comes from solid solution plus coarse grain, producing predictable, stable creep behaviour and higher allowable stresses.

## Incoloy 825 (UNS N08825)
URL: https://www.hb-nickelalloy.com/alloys/incoloy-825/
Family: Incoloy Alloys
Equivalents: DIN 2.4858; GB NS1402 / 0Cr21Ni42Mo3Cu2Ti
Incoloy 825 (UNS N08825) is a molybdenum- and copper-bearing nickel-iron-chromium alloy, titanium stabilised. It combines resistance to sulphuric and phosphoric acid, seawater and stress-corrosion cracking, making it a workhorse for sour oil and gas, chemical heat exchangers and nuclear fuel reprocessing.
Composition (wt%): Ni 38.0–46.0; Cr 19.5–23.5; Fe ≥ 22.0; Mo 2.5–3.5; Cu 1.50–3.00; Ti 0.60–1.20; Al ≤ 0.20; C ≤ 0.05; Mn ≤ 1.00; Si ≤ 0.50
Mechanical (RT): tensile ≥ 586 MPa; yield ≥ 241 MPa; elongation ≥ 30 %; hardness ≤ 190 HB
Physical: density 8.14 g/cm³; melting 1370–1400 °C; thermal conductivity 11.1 W/m·K; modulus 196 GPa; max service 1000 °C
Standards: ASTM B425; ASTM B424; ASTM B423; ASTM B564; NACE MR0175 / ISO 15156; UNS N08825
Applications: Sour oil and gas tubing, valves and heat exchangers; Sulphuric acid pickling and acid recovery; Nuclear fuel reprocessing dissolvers; Seawater coolers and marine piping; Chemical process piping and vessels
Q: How do I choose between Incoloy 825 and Inconel 625 for sour service?
A: In standard sour conditions (moderate H₂S partial pressure, below about 150 °C), 825 fully satisfies NACE MR0175 at lower cost and is the mainstay choice. When H₂S partial pressure is high, elemental sulphur is present, temperature exceeds 150–200 °C or chlorides are heavy, upgrade to 625 or 725.
Q: Can Incoloy 825 be used in seawater?
A: Yes, it is widely used for seawater coolers and marine piping. However, localised corrosion can still occur in stagnant seawater or where crevices and deposits exist. With flowing, well-aerated seawater and regular cleaning, 825 performs well; for higher crevice-corrosion resistance consider 625 or C-276.

## Incoloy 926 (UNS N08926)
URL: https://www.hb-nickelalloy.com/alloys/incoloy-926/
Family: Incoloy Alloys
Equivalents: DIN 1.4529; GB 00Cr20Ni25Mo6CuN
Incoloy 926 (UNS N08926, equivalent to 1.4529 / 25-6Mo) is a high-molybdenum nitrogen-bearing superaustenitic alloy with PREN around 43–47. Pitting and crevice resistance approach Inconel 625 at markedly lower cost.
Composition (wt%): Ni 24.0–26.0; Cr 19.0–21.0; Mo 6.0–7.0; Cu 0.50–1.50; N 0.15–0.25; Fe Balance; Mn ≤ 2.00; Si ≤ 0.50; C ≤ 0.020
Mechanical (RT): tensile ≥ 650 MPa; yield ≥ 295 MPa; elongation ≥ 35 %; hardness ≤ 200 HB
Physical: density 8.10 g/cm³; melting 1320–1390 °C; thermal conductivity 12.0 W/m·K; modulus 195 GPa; max service 1000 °C
Standards: ASTM B649; ASTM B625; ASTM B673; UNS N08926
Applications: Desalination and seawater cooling systems; FGD absorbers and ducting; Pulp bleaching and chlor-alkali industry; Chloride-bearing chemical heat exchangers; Offshore firewater and ballast systems
Q: How does Incoloy 926 relate to 254SMO?
A: They are very close in chemistry and performance — 926 (N08926) and 254SMO (S31254) are both 6% Mo superaustenitic grades with PREN in the 43–47 range and are often interchangeable. Final selection should follow the applicable standard, the product form required and design allowable stresses; Hangbo supplies both.

## Incoloy A-286 (UNS S66286)
URL: https://www.hb-nickelalloy.com/alloys/incoloy-a-286/
Family: Incoloy Alloys
Equivalents: DIN 1.4980; GB GH2132 / GH132
Incoloy A-286 (UNS S66286, equivalent to Chinese GH2132) is an iron-nickel-chromium precipitation-hardening superalloy. Below 700 °C it offers high strength and good oxidation resistance at lower cost than nickel-base superalloys, and is among the most heavily used grades for aerospace fasteners and turbine parts.
Composition (wt%): Ni 24.0–27.0; Cr 13.5–16.0; Fe Balance; Ti 1.90–2.35; Mo 1.00–1.50; V 0.10–0.50; Al ≤ 0.35; B 0.001–0.010; C ≤ 0.08; Mn ≤ 2.00; Si ≤ 1.00
Mechanical (RT): tensile ≥ 895 MPa (aged); yield ≥ 585 MPa (aged); elongation ≥ 15 %; hardness ≥ 28 HRC
Physical: density 7.93 g/cm³; melting 1370–1430 °C; thermal conductivity 15.1 W/m·K; modulus 201 GPa; max service 700 °C
Standards: ASTM B637; AMS 5731; AMS 5737; UNS S66286
Applications: Aero-engine bolts, fasteners and springs; Gas turbine discs and blades; Automotive turbocharger components; High-temperature oilfield parts; Nuclear and chemical high-temperature bolting
Q: What is the standard heat treatment for A-286?
A: A common cycle is solution treatment at 980 °C for 1 hour with oil quench or air cool, followed by ageing at 720 °C for 16 hours and air cooling (AMS 5731/5732). Parts needing better creep performance may use a 900 °C solution plus a 720 °C/650 °C double age.

## Inconel 600 (UNS N06600)
URL: https://www.hb-nickelalloy.com/alloys/inconel-600/
Family: Inconel Alloys
Equivalents: DIN 2.4816; GB GH3600 / NS3102
Inconel 600 (UNS N06600) is a solid-solution strengthened nickel-chromium-iron alloy with at least 72% nickel and 14–17% chromium. It combines high-temperature oxidation resistance, resistance to chloride stress-corrosion cracking and good hot/cold workability, making it a classic choice for furnace components, chemical equipment and nuclear parts.
Composition (wt%): Ni ≥ 72.0; Cr 14.0–17.0; Fe 6.0–10.0; C ≤ 0.15; Mn ≤ 1.00; Si ≤ 0.50; Cu ≤ 0.50; S ≤ 0.015
Mechanical (RT): tensile ≥ 550 MPa; yield ≥ 240 MPa; elongation ≥ 30 %; hardness ≤ 180 HB
Physical: density 8.47 g/cm³; melting 1354–1413 °C; thermal conductivity 14.9 W/m·K; modulus 207 GPa; max service 1095 °C (oxidation resistant)
Standards: ASTM B166; ASTM B168; ASTM B167; AMS 5540; UNS N06600
Applications: Heat-treat furnace rollers, muffles, radiant tubes and baskets; Chemical evaporators and fatty acid processing equipment; Nuclear steam generator tubing and supports; Electronic components and vacuum tube parts; Caustic soda and organic chloride production plant
Q: How does Inconel 600 differ from 304 or 316L stainless steel?
A: Inconel 600 contains about 72% nickel versus roughly 8% in 304 and 10% in 316L. The high nickel makes it virtually immune to chloride stress-corrosion cracking and lets it resist oxidation above 1000 °C, while 300-series stainless risks SCC in chlorides above about 60 °C and is generally limited to 870 °C in air.
Q: Which standards cover Inconel 600 mill products?
A: ASTM B166 for bar, B168 for plate/sheet/strip, B167 for seamless tube, B564 for forgings, plus AMS 5540/5665 for aerospace. Hangbo supplies to these specifications with EN 10204 3.1 certification.
Q: Is Inconel 600 weldable and which filler metal should be used?
A: Yes. ERNiCr-3 (Inconel 82) is the standard TIG/MIG filler; submerged arc uses ENiCrFe-3 wire with a matched flux. Clean the joint thoroughly and keep interpass temperature below 150 °C.

## Inconel 601 (UNS N06601)
URL: https://www.hb-nickelalloy.com/alloys/inconel-601/
Family: Inconel Alloys
Equivalents: DIN 2.4851; GB GH3601 / NS3103
Inconel 601 (UNS N06601) raises the chromium level of 600 and adds 1.0–1.7% aluminium, producing a dense Cr₂O₃/Al₂O₃ scale that resists oxidation to 1250 °C. It excels against carburisation and cyclic oxidation, making it a first choice for heat-treating and petrochemical cracking furnaces.
Composition (wt%): Ni 58.0–63.0; Cr 21.0–25.0; Al 1.00–1.70; Fe 7.7–17.4; C ≤ 0.10; Mn ≤ 1.00; Si ≤ 0.50; Cu ≤ 1.00; S ≤ 0.015
Mechanical (RT): tensile ≥ 600 MPa; yield ≥ 300 MPa; elongation ≥ 30 %; hardness ≤ 190 HB
Physical: density 8.11 g/cm³; melting 1320–1370 °C; thermal conductivity 11.2 W/m·K; modulus 206 GPa; max service 1250 °C (oxidation resistant)
Standards: ASTM B166; ASTM B168; ASTM B167; UNS N06601
Applications: Radiant tubes, rollers, muffles and fixtures for heat-treat furnaces; Petrochemical cracking and reformer furnace components; Industrial burners, flare tips and exhaust systems; Waste incineration and heat-treat baskets; Glass and ceramic kiln furniture
Q: What is the advantage of Inconel 601 over 600?
A: 601 raises chromium to 21–25% and adds 1.0–1.7% aluminium, lifting oxidation resistance from about 1095 °C (600) to 1250 °C with markedly better carburisation and thermal-fatigue performance. Choose 601 when service exceeds 900 °C or carburising atmospheres are present.
Q: How does Inconel 601 behave in sulphidising atmospheres?
A: 601 performs well in oxidising sulphur-bearing gases, but nickel forms low-melting eutectics with sulphur, so reducing high-sulphur (low-oxygen) environments require careful evaluation — consider high-chromium iron-base alloys or a service simulation test.

## Inconel 617 (UNS N06617)
URL: https://www.hb-nickelalloy.com/alloys/inconel-617/
Family: Inconel Alloys
Equivalents: DIN 2.4663; GB GH3617
Inconel 617 (UNS N06617) is a solid-solution Ni-Cr-Co-Mo superalloy combining high-temperature strength with oxidation and carburisation resistance. It is a key candidate for supercritical CO₂ cycles, advanced ultra-supercritical power plant and high-temperature gas-cooled reactor heat exchangers.
Composition (wt%): Ni ≥ 44.5; Cr 20.0–24.0; Co 10.0–15.0; Mo 8.0–10.0; Al 0.80–1.50; Fe ≤ 3.0; C 0.05–0.15; Ti ≤ 0.60; Si ≤ 1.00; Mn ≤ 1.00
Mechanical (RT): tensile ≥ 655 MPa; yield ≥ 300 MPa; elongation ≥ 30 %; hardness ≤ 200 HB
Physical: density 8.36 g/cm³; melting 1330–1380 °C; thermal conductivity 13.4 W/m·K; modulus 211 GPa; max service 1100 °C
Standards: ASTM B166; ASTM B168; ASTM B167; ASTM B564; UNS N06617
Applications: Gas turbine combustors and transition ducts; High-temperature gas-cooled reactor intermediate heat exchangers; Supercritical CO₂ cycle heat exchangers and piping; Pigtails and collector pipes in reformer furnaces; High-temperature heat-treat fixtures
Q: What is the maximum service temperature of Inconel 617?
A: In oxidising atmospheres 617 resists oxidation to about 1100 °C. For load-bearing design the temperature must be chosen from creep and allowable stress data (for example ASME BPVC Section II Part D); long-term stressed design commonly falls in the 900–980 °C range.

## Inconel 625 (UNS N06625)
URL: https://www.hb-nickelalloy.com/alloys/inconel-625/
Family: Inconel Alloys
Equivalents: DIN 2.4856; GB GH3625 / NS3306
Inconel 625 (UNS N06625) is a Ni-Cr alloy strengthened mainly by molybdenum and niobium in solid solution. It reaches high strength without ageing heat treatment and offers a balanced combination of oxidation and corrosion resistance plus fatigue strength, making it one of the most widely used nickel alloys in offshore, chemical, nuclear and aerospace service.
Composition (wt%): Ni ≥ 58.0; Cr 20.0–23.0; Mo 8.0–10.0; Nb+Ta 3.15–4.15; Fe ≤ 5.0; Co ≤ 1.00; Al ≤ 0.40; Ti ≤ 0.40; C ≤ 0.10; Mn ≤ 0.50; Si ≤ 0.50; P ≤ 0.015; S ≤ 0.015
Mechanical (RT): tensile ≥ 830 MPa; yield ≥ 414 MPa; elongation ≥ 30 %; hardness ≤ 200 HB
Physical: density 8.44 g/cm³; melting 1290–1350 °C; thermal conductivity 9.8 W/m·K; modulus 205 GPa; max service 980 °C
Standards: ASTM B446; ASTM B443; ASTM B444; ASTM B564; AMS 5666; NACE MR0175 / ISO 15156; UNS N06625
Applications: Desalination and marine piping, pump shafts; Flue-gas desulphurisation (FGD) systems; Chemical reactors, heat exchangers and pickling equipment; Nuclear and gas turbine piping systems; Aero-engine exhaust systems and thrust reversers; Sour oil and gas downhole tools and valves
Q: How do I choose between Inconel 625 and Inconel 718?
A: They are strengthened differently. 625 relies on Mo and Nb in solid solution, keeps its corrosion resistance as welded without post-weld heat treatment, and suits corrosion service and welded fabrications such as piping, vessels and seawater systems. 718 is precipitation hardened by γ″/γ′ and reaches roughly 1400 MPa after ageing, suiting highly stressed parts such as turbine discs and fasteners. Pick 625 when corrosion dominates and 718 when strength dominates.
Q: Does Inconel 625 need post-weld heat treatment?
A: Normally no. As a solid-solution alloy it has no age-hardening requirement after welding. For thick or highly restrained fabrications, a stress relief at 870–980 °C may be used, avoiding the 650–870 °C sensitising range where carbides precipitate.
Q: What is the typical PREN of Inconel 625?
A: Using PREN = %Cr + 3.3×%Mo + 16×%N with typical Cr 21.5% and Mo 9%, the value is about 51. With niobium contribution and measured data, engineering practice places 625 PREN in the 45–52 range — well above 316L (about 26) and 904L (about 36).

## Inconel 690 (UNS N06690)
URL: https://www.hb-nickelalloy.com/alloys/inconel-690/
Family: Inconel Alloys
Equivalents: DIN 2.4642; GB NS3105
Inconel 690 (UNS N06690) raises chromium to 27–31% and is the replacement material for PWR nuclear steam generator tubing, offering far better intergranular corrosion and stress-corrosion-cracking resistance than Inconel 600 or the 800 series.
Composition (wt%): Ni ≥ 58.0; Cr 27.0–31.0; Fe 7.0–11.0; C ≤ 0.05; Mn ≤ 0.50; Si ≤ 0.50; Cu ≤ 0.50; S ≤ 0.015
Mechanical (RT): tensile ≥ 586 MPa; yield ≥ 240 MPa; elongation ≥ 30 %; hardness ≤ 190 HB
Physical: density 8.19 g/cm³; melting 1343–1377 °C; thermal conductivity 11.1 W/m·K; modulus 211 GPa; max service 1000 °C
Standards: ASTM B166; ASTM B168; ASTM B163; ASTM B167; UNS N06690
Applications: PWR steam generator tubing; Nuclear evaporators and tube supports; Nitric acid production equipment; Waste incinerator superheater tubes; High-temperature chloride-bearing chemical plant
Q: Why did nuclear steam generator tubing move from Inconel 600 to 690?
A: 600 suffered primary- and secondary-side stress-corrosion cracking in high-temperature, high-pressure borated water. 690 raises chromium to about 30%, sharply reducing grain-boundary chromium depletion and improving SCC resistance by more than an order of magnitude, which is why it became the standard for PWR SG tubing.

## Inconel 718 (UNS N07718)
URL: https://www.hb-nickelalloy.com/alloys/inconel-718/
Family: Inconel Alloys
Equivalents: DIN 2.4668; GB GH4169
Inconel 718 (UNS N07718) is the world's most widely used precipitation-hardening nickel superalloy, strengthened by γ″ (Ni₃Nb) and γ′ phases. Below 650 °C it delivers very high yield strength plus creep and fatigue resistance, and accounts for roughly a third of all superalloy used in aero-engines and industrial gas turbines.
Composition (wt%): Ni 50.0–55.0; Cr 17.0–21.0; Fe Balance; Nb+Ta 4.75–5.50; Mo 2.80–3.30; Ti 0.65–1.15; Al 0.20–0.80; Co ≤ 1.00; C ≤ 0.08; Mn ≤ 0.35; Si ≤ 0.35; B ≤ 0.006
Mechanical (RT): tensile ≥ 1275 MPa (aged); yield ≥ 1035 MPa (aged); elongation ≥ 12 %; hardness ≥ 36 HRC
Physical: density 8.19 g/cm³; melting 1260–1340 °C; thermal conductivity 11.4 W/m·K; modulus 200 GPa; max service 650 °C
Standards: ASTM B637; ASTM B670; AMS 5662; AMS 5663; NACE MR0175 / ISO 15156; UNS N07718
Applications: Aero-engine turbine discs, blades, shafts and fasteners; Industrial gas turbine hot-section components; Oil and gas downhole tools, packers and valves; Cryogenic engineering (tough to −253 °C); High-strength springs and diaphragms
Q: What is the standard heat treatment for Inconel 718?
A: The common cycle is solution treatment at 955–980 °C followed by air cooling (or 1065 °C per AMS 5662), then double ageing: 720 °C for 8 hours, furnace cool to 620 °C, hold 8 hours and air cool — about 18 hours of ageing in total. This gives the best strength/toughness balance and meets AMS 5663 properties.
Q: Can Inconel 718 and 625 be used interchangeably?
A: Generally not. 718 gains high strength through ageing but is slightly less corrosion resistant; 625 offers better corrosion resistance but tops out near 830 MPa tensile. Choose 718 when strength governs the design and 625 when corrosion life and weldability govern.

## Inconel 725 (UNS N07725)
URL: https://www.hb-nickelalloy.com/alloys/inconel-725/
Family: Inconel Alloys
Equivalents: DIN —; GB —
Inconel 725 (UNS N07725) combines the corrosion resistance of Inconel 625 with age-hardening strength — roughly twice the yield of 625 — making it the preferred choice for sour downhole tools, high-strength fasteners and valve stems.
Composition (wt%): Ni 55.0–59.0; Cr 19.0–22.5; Mo 7.0–9.5; Nb 2.75–4.00; Ti 1.00–1.70; Fe Balance; Al ≤ 0.35; C ≤ 0.03; Mn ≤ 0.35; Si ≤ 0.20
Mechanical (RT): tensile ≥ 1137 MPa (aged); yield ≥ 827 MPa (aged); elongation ≥ 20 %; hardness ≥ 32 HRC
Physical: density 8.31 g/cm³; melting 1271–1343 °C; thermal conductivity 10.6 W/m·K; modulus 204 GPa; max service 650 °C
Standards: ASTM B805; NACE MR0175 / ISO 15156; UNS N07725
Applications: Sour oil and gas downhole tools, packers and hangers; High-strength valve stems, fasteners and lifting gear; High-strength shafts for corrosive chemical service; Offshore mooring and tensioner components
Q: What advantage does Inconel 725 have over 718?
A: 725 carries more chromium and molybdenum (Cr 19–22.5%, Mo 7–9.5%), so it is clearly more corrosion resistant than 718 while ageing to comparable strength via Ti and Nb. Where NACE MR0175 sour compliance and 718-class strength are both required, 725 is the stronger answer.

## Inconel X-750 (UNS N07750)
URL: https://www.hb-nickelalloy.com/alloys/inconel-x-750/
Family: Inconel Alloys
Equivalents: DIN 2.4669; GB GH4145
Inconel X-750 (UNS N07750) is a Ni-Cr alloy precipitation hardened by γ′ through titanium, aluminium and niobium. It retains high strength and relaxation resistance below 700 °C and is a classic choice for high-temperature springs, turbine blades and nuclear reactor internals.
Composition (wt%): Ni ≥ 70.0; Cr 14.0–17.0; Fe 5.0–9.0; Ti 2.25–2.75; Al 0.40–1.00; Nb+Ta 0.70–1.20; Co ≤ 1.00; C ≤ 0.08; Mn ≤ 1.00; Si ≤ 0.50
Mechanical (RT): tensile ≥ 1170 MPa (aged); yield ≥ 790 MPa (aged); elongation ≥ 15 %; hardness ≥ 30 HRC
Physical: density 8.28 g/cm³; melting 1393–1427 °C; thermal conductivity 12.0 W/m·K; modulus 214 GPa; max service 700 °C
Standards: ASTM B637; AMS 5667; AMS 5698; UNS N07750
Applications: Aero-engine turbine blades and bolts; High-temperature coil and disc springs, seal rings; Nuclear reactor internals and hold-down springs; Gas turbine blades and rotor bolts; Heat-treat fixtures
Q: What heat treatment is used for X-750 springs?
A: Spring temper typically uses solution treatment at 1150 °C, ageing at 843 °C for 24 hours, air cool, then 704 °C for 20 hours and air cool (AMS 5698/5699), giving the best relaxation resistance. Structural parts needing higher strength use 980 °C solution plus a 732 °C/620 °C double age.

## Invar 36 / 4J36 (UNS K93600)
URL: https://www.hb-nickelalloy.com/alloys/precision-4j36/
Family: Precision Alloys
Equivalents: DIN 1.3912; GB 4J36
4J36 (Invar 36, UNS K93600) is a 36% nickel low-expansion iron-nickel alloy with a mean coefficient of thermal expansion of about 1.2×10⁻⁶/°C from −80 to +100 °C — roughly one tenth that of ordinary steel. It is used where dimensional stability is critical: precision instruments, LNG tanks and composite tooling.
Composition (wt%): Fe Balance; Ni 35.0–37.0; Co ≤ 0.50; Mn 0.20–0.60; Si ≤ 0.30; C ≤ 0.05; P ≤ 0.020; S ≤ 0.020
Mechanical (RT): tensile ≥ 440 MPa; yield ≥ 240 MPa; elongation ≥ 30 %; hardness ≤ 170 HB
Physical: density 8.10 g/cm³; melting 1430–1450 °C; thermal conductivity 10.5 W/m·K; modulus 141 GPa; max service −80 ~ +100 ℃ (dimensional stability range)
Standards: ASTM F1684; GB/T 14985; UNS K93600
Applications: LNG carrier tanks and transfer piping; Precision instruments, clocks and measurement standards; Aerospace composite lay-up tooling; Electronic packaging and lead frames; Liquefied gas tank liners
Q: Why is Invar 36's expansion so low?
A: This is the Invar effect: the 36% nickel iron-nickel alloy exhibits volume magnetostriction below its Curie temperature, so the normal lattice expansion with temperature is offset by magnetic contraction, giving very low net thermal expansion. Above the Curie point (about 230 °C) the CTE rises rapidly to that of ordinary steel.

## Kovar / 4J29 (UNS K94610)
URL: https://www.hb-nickelalloy.com/alloys/precision-4j29/
Family: Precision Alloys
Equivalents: DIN 1.3981; GB 4J29
4J29 (Kovar, UNS K94610) is an iron-nickel-cobalt controlled-expansion sealing alloy. With a CTE of about 4.6–5.2×10⁻⁶/°C from 20 to 450 °C it matches borosilicate glass and alumina ceramic, making it the standard for vacuum tubes, semiconductor packaging and hermetic seals.
Composition (wt%): Fe Balance; Ni 28.5–29.5; Co 16.8–17.8; Mn ≤ 0.50; Si ≤ 0.30; C ≤ 0.03; P ≤ 0.020; S ≤ 0.020
Mechanical (RT): tensile ≥ 520 MPa; yield ≥ 340 MPa; elongation ≥ 25 %; hardness ≤ 190 HB
Physical: density 8.36 g/cm³; melting 1450–1470 °C; thermal conductivity 17.0 W/m·K; modulus 138 GPa; max service −80 ~ +450 ℃
Standards: ASTM F15; GB/T 14985; UNS K94610
Applications: IC and power device packages; Vacuum tubes, magnetrons and travelling-wave tubes; Aerospace and military hermetic electronic packaging; Sensor and relay housings; Solar cell and laser device packaging
Q: What is the difference between 4J29 and 4J36?
A: 4J36 (Invar) targets minimal expansion (about 1.2×10⁻⁶/°C) for dimensionally stable parts, while 4J29 (Kovar) targets a controlled expansion (about 5×10⁻⁶/°C) matched to glass and ceramic for hermetic sealing. 4J29 contains 17% cobalt and costs more; the two are not interchangeable.

## Monel 400 (UNS N04400)
URL: https://www.hb-nickelalloy.com/alloys/monel-400/
Family: Monel Alloys
Equivalents: DIN 2.4360; GB NCu30 / B30
Monel 400 (UNS N04400) is a solid-solution nickel-copper alloy (Ni ≥ 63%, Cu 28–34%) with excellent resistance to seawater, hydrofluoric acid, sulphuric acid and alkalis, plus higher strength than pure nickel. It is a classic material for marine engineering, pump shafts and valves.
Composition (wt%): Ni ≥ 63.0; Cu 28.0–34.0; Fe ≤ 2.5; Mn ≤ 2.00; C ≤ 0.30; Si ≤ 0.50; S ≤ 0.024
Mechanical (RT): tensile ≥ 480 MPa; yield ≥ 195 MPa; elongation ≥ 35 %; hardness ≤ 170 HB
Physical: density 8.80 g/cm³; melting 1300–1350 °C; thermal conductivity 21.8 W/m·K; modulus 179 GPa; max service 600 °C
Standards: ASTM B164; ASTM B127; ASTM B165; ASTM B564; UNS N04400
Applications: Marine and desalination piping, pump shafts and propellers; HF acid production, storage and transfer equipment; Crude distillation overhead condensing systems; Valves, pump bodies and fasteners; Musical instrument strings and architectural roofing
Q: What is the difference between Monel 400 and Monel K-500?
A: K-500 adds 2.3–3.15% aluminium and 0.35–0.85% titanium to the 400 chemistry and is strengthened by γ′ ageing, giving two to three times the yield strength of 400 (around 690 MPa) and much higher hardness. However, K-500 is slightly less corrosion resistant than 400 in some acids and its aged condition needs care regarding stress-corrosion susceptibility.
Q: How well does Monel 400 resist seawater?
A: Very well. In flowing seawater the corrosion rate is typically below 0.025 mm/a and it resists cavitation and impingement, which is why it has long been used for pump shafts, propeller shafts and heat exchangers. In stagnant seawater or where sulphide contamination exists, pitting can occur — avoid long stagnation and control sulphides.

## Monel K-500 (UNS N05500)
URL: https://www.hb-nickelalloy.com/alloys/monel-k-500/
Family: Monel Alloys
Equivalents: DIN 2.4375; GB NCu30Al
Monel K-500 (UNS N05500) is a precipitation-hardening nickel-copper alloy. It keeps the seawater corrosion resistance of Monel 400 while γ′ ageing with aluminium and titanium raises strength two to three times, suiting high-strength marine shafts, drill collars, scrapers and springs.
Composition (wt%): Ni ≥ 63.0; Cu 27.0–33.0; Al 2.30–3.15; Ti 0.35–0.85; Fe ≤ 2.0; Mn ≤ 1.50; C ≤ 0.18; Si ≤ 0.50; S ≤ 0.010
Mechanical (RT): tensile ≥ 965 MPa (aged); yield ≥ 690 MPa (aged); elongation ≥ 20 %; hardness ≥ 27 HRC
Physical: density 8.44 g/cm³; melting 1315–1350 °C; thermal conductivity 17.5 W/m·K; modulus 179 GPa; max service 600 °C
Standards: ASTM B865; ASTM B127; AMS 4676; NACE MR0175 / ISO 15156; UNS N05500
Applications: Non-magnetic drill collars and MWD instrument housings; Marine pump shafts, propeller shafts and scrapers; Oil and gas packers, valve stems and springs; Paper machine doctor blades; High-strength fasteners
Q: What heat treatment does Monel K-500 use?
A: A typical cycle is solution annealing at 980 °C with rapid cooling, then ageing at 593–607 °C for 16 hours with furnace cooling (about 10 °C/h) to 482 °C followed by air cooling to reach standard aged properties. Stress relieving, when needed for stress-corrosion control, is usually done at 552–593 °C.

## Nickel 200 (UNS N02200)
URL: https://www.hb-nickelalloy.com/alloys/nickel-200/
Family: Pure Nickel
Equivalents: DIN 2.4066; GB N6 / Ni200
Nickel 200 (UNS N02200) is commercially pure nickel with at least 99.0% Ni. It offers excellent resistance to caustic alkalis, good electrical and thermal conductivity and high ductility, and is the standard material for chlor-alkali plant, electronic components and food processing equipment.
Composition (wt%): Ni+Co ≥ 99.0; Cu ≤ 0.25; Fe ≤ 0.40; Mn ≤ 0.35; C ≤ 0.15; Si ≤ 0.35; S ≤ 0.010
Mechanical (RT): tensile ≥ 380 MPa; yield ≥ 100 MPa; elongation ≥ 40 %; hardness ≤ 120 HB
Physical: density 8.89 g/cm³; melting 1435–1446 °C; thermal conductivity 70.2 W/m·K; modulus 205 GPa; max service 315 °C
Standards: ASTM B160; ASTM B162; ASTM B161; UNS N02200
Applications: Caustic soda evaporators in chlor-alkali plants; Food processing and synthetic fibre equipment; Electronic tubes and battery electrodes; Aerospace structural parts; Chemical piping for caustic service
Q: Should I choose Nickel 200 or 201?
A: Use 200 (C ≤ 0.15%) below 315 °C. Above 315 °C carbon precipitates as graphite at grain boundaries and causes embrittlement, so the low-carbon 201 (C ≤ 0.02%) is mandatory, extending usable temperature to 600 °C.

## Nickel 201 (UNS N02201)
URL: https://www.hb-nickelalloy.com/alloys/nickel-201/
Family: Pure Nickel
Equivalents: DIN 2.4068; GB N4 / Ni201
Nickel 201 (UNS N02201) is the low-carbon version of Nickel 200 (C ≤ 0.02%). It avoids grain-boundary graphitisation at elevated temperature, raising the service limit to 600 °C for high-temperature caustic and electronic applications.
Composition (wt%): Ni+Co ≥ 99.0; Cu ≤ 0.25; Fe ≤ 0.40; Mn ≤ 0.35; C ≤ 0.02; Si ≤ 0.35; S ≤ 0.010
Mechanical (RT): tensile ≥ 345 MPa; yield ≥ 80 MPa; elongation ≥ 40 %; hardness ≤ 110 HB
Physical: density 8.89 g/cm³; melting 1435–1446 °C; thermal conductivity 70.2 W/m·K; modulus 205 GPa; max service 600 °C
Standards: ASTM B160; ASTM B162; ASTM B161; UNS N02201
Applications: High-temperature caustic concentrators; Electronic tube cathodes and leads; Synthetic fibre spinnerets; High-temperature aerospace parts; Chemical reactor linings
Q: Why is carbon limited in Nickel 201?
A: During long service above 315 °C, supersaturated carbon migrates to grain boundaries and precipitates as graphite, sharply reducing ductility and toughness. Holding carbon below 0.02% essentially removes this risk, allowing safe use up to 600 °C.

## Nimonic 75 (UNS N06075)
URL: https://www.hb-nickelalloy.com/alloys/nimonic-75/
Family: Nimonic Alloys
Equivalents: DIN 2.4951; GB GH3030
Nimonic 75 (UNS N06075) is a Ni-Cr solid-solution high-temperature alloy containing about 19–21% chromium. It is not precipitation hardenable and relies on solid-solution strengthening and outstanding oxidation resistance, giving long service in oxidising atmospheres up to about 1000 °C. It is widely used in gas-turbine combustors, furnace components, heat-treatment fixtures and hot chemical plant parts.
Composition (wt%): Ni Balance; Cr 18.0–21.0; Fe ≤ 5.0; Ti 0.20–0.60; C ≤ 0.12; Si ≤ 1.00; Mn ≤ 1.00; Cu ≤ 0.50
Mechanical (RT): tensile ≥ 560 MPa (annealed); yield ≥ 245 MPa (annealed); elongation ≥ 30 %; hardness ≤ 200 HB
Physical: density 8.37 g/cm³; melting 1340–1390 °C; thermal conductivity 14.6 W/m·K; modulus 200 GPa; max service 1000 °C
Standards: Werkstoff 2.4951; DIN 17744; AMS 5750; UNS N06075
Applications: Gas-turbine combustors and flame tubes; Furnace components and heat-treatment fixtures; Hot chemical plant and heat exchangers; Sheet, strip and welding-wire products
Q: How do Nimonic 75 and 80A differ?
A: 75 is a solid-solution alloy, not age-hardenable, relying on about 20% chromium for oxidation resistance up to roughly 1000 °C in oxidising atmospheres, but its strength is far below 80A. 80A is γ′ precipitation-hardened and much stronger, yet its service temperature is typically below 815 °C. Choose 80A for creep strength and 75 where oxidation resistance, formability and weldability matter.

## Nimonic 80A (UNS N07080)
URL: https://www.hb-nickelalloy.com/alloys/nimonic-80a/
Family: Nimonic Alloys
Equivalents: DIN 2.4952; GB GH4080A
Nimonic 80A (UNS N07080) is a Ni-Cr superalloy precipitation hardened by γ′ with 1.8–2.7% Ti and 1.0–1.8% Al. Below 815 °C it offers excellent creep strength and oxidation resistance, serving aero-engine turbine blades, exhaust valves and high-temperature bolting.
Composition (wt%): Ni Balance; Cr 18.0–21.0; Ti 1.80–2.70; Al 1.00–1.80; Co ≤ 2.00; Fe ≤ 3.0; C ≤ 0.10; Si ≤ 1.00; Mn ≤ 1.00; B ≤ 0.008
Mechanical (RT): tensile ≥ 1000 MPa (aged); yield ≥ 620 MPa (aged); elongation ≥ 20 %; hardness ≥ 28 HRC
Physical: density 8.19 g/cm³; melting 1320–1365 °C; thermal conductivity 11.2 W/m·K; modulus 222 GPa; max service 815 °C
Standards: ASTM B637; AMS 5766; BS HR 401; UNS N07080
Applications: Aero-engine turbine and guide vanes; Internal combustion exhaust valves; High-temperature bolts and springs; Gas turbine components; High-temperature nuclear fasteners
Q: How do the strength ranges of Nimonic 80A and Inconel 718 compare?
A: 80A is γ′ strengthened and has better creep strength than 718 between 700 and 815 °C. 718 relies on γ″ and is stronger below 650 °C, but γ″ coarsens rapidly above that. Choose 80A for high-temperature creep service and 718 for mid-temperature high strength.

## Nimonic 90 (UNS N07090)
URL: https://www.hb-nickelalloy.com/alloys/nimonic-90/
Family: Nimonic Alloys
Equivalents: DIN 2.4632; GB GH4090
Nimonic 90 (UNS N07090) contains 15–21% cobalt and is among the strongest grades in the Nimonic series, retaining creep and oxidation resistance to 920 °C in turbine blades, high-temperature springs and fasteners.
Composition (wt%): Ni Balance; Cr 18.0–21.0; Co 15.0–21.0; Ti 2.00–3.00; Al 1.00–2.00; Fe ≤ 3.0; C ≤ 0.13; Si ≤ 1.00; Mn ≤ 1.00; B ≤ 0.020
Mechanical (RT): tensile ≥ 1080 MPa (aged); yield ≥ 700 MPa (aged); elongation ≥ 18 %; hardness ≥ 30 HRC
Physical: density 8.18 g/cm³; melting 1310–1370 °C; thermal conductivity 11.5 W/m·K; modulus 225 GPa; max service 920 °C
Standards: BS HR 202; AMS 5829; UNS N07090
Applications: Aero-engine turbine blades and discs; High-temperature springs and seal rings; Exhaust valves and turbocharger rotors; High-temperature nuclear components
Q: What heat treatment does Nimonic 90 use?
A: A typical cycle is solution treatment at 1080 °C for 8 hours, air cool, then ageing at 700 °C for 16 hours and air cooling. For spring applications a cold-draw plus ageing combination can raise strength further.

## Stainless Steel 17-4PH (UNS S17400)
URL: https://www.hb-nickelalloy.com/alloys/stainless-17-4ph/
Family: Stainless Steel
Equivalents: DIN 1.4542; GB 05Cr17Ni4Cu4Nb
17-4PH (UNS S17400) is a martensitic precipitation-hardening stainless strengthened by copper. Machined in the solution-annealed state and given a single low-temperature age (H900–H1150), it reaches 930–1310 MPa tensile and HRC 30–45, balancing strength with corrosion resistance.
Composition (wt%): Fe Balance; Cr 15.0–17.5; Ni 3.00–5.00; Cu 3.00–5.00; Nb+Ta 0.15–0.45; Mn ≤ 1.00; Si ≤ 1.00; C ≤ 0.070
Mechanical (RT): tensile ≥ 1310 MPa（H900）; yield ≥ 1170 MPa（H900）; elongation ≥ 10 %; hardness ≥ 40 HRC
Physical: density 7.80 g/cm³; melting 1404–1440 °C; thermal conductivity 17.9 W/m·K; modulus 196 GPa; max service 300 °C (caution above H900)
Standards: ASTM A564; ASTM A693; AMS 5604; UNS S17400
Applications: Aerospace structures and engine parts; Valves, pump shafts and fasteners; Oilfield machinery and downhole tools; Moulds and extruder screws; Medical and surgical instruments
Q: Should I choose 17-4PH in H900 or H1150 condition?
A: H900 (482 °C for 1 h) gives maximum strength (tensile ≥ 1310 MPa, HRC 40+) but the lowest toughness and higher stress-corrosion susceptibility. H1150 (621 °C for 4 h) is weaker (about 1000 MPa tensile, HRC 31) but has the best toughness and SCC resistance. In chloride or sulphide service prefer H1100 or H1150.

## Stainless Steel 304 (UNS S30400)
URL: https://www.hb-nickelalloy.com/alloys/stainless-304/
Family: Stainless Steel
Equivalents: DIN 1.4301; GB 06Cr19Ni10
Stainless 304 (UNS S30400) is the most widely used 18-8 austenitic stainless with 18% chromium and 8% nickel. It offers good corrosion resistance, formability and weldability, making it the standard for food equipment, kitchenware, chemical vessels and architectural decoration.
Composition (wt%): Fe Balance; Cr 18.0–20.0; Ni 8.0–10.5; Mn ≤ 2.00; Si ≤ 1.00; C ≤ 0.080; P ≤ 0.045; S ≤ 0.030
Mechanical (RT): tensile ≥ 515 MPa; yield ≥ 205 MPa; elongation ≥ 40 %; hardness ≤ 201 HB
Physical: density 7.93 g/cm³; melting 1398–1454 °C; thermal conductivity 16.2 W/m·K; modulus 193 GPa; max service 870 °C
Standards: ASTM A276; ASTM A240; ASTM A312; ASTM A182; UNS S30400
Applications: Food processing and kitchen equipment; Architectural decoration and cladding; Atmospheric chemical vessels and piping; Drinking and domestic water systems; Household appliances and tableware
Q: What is the difference between 304 and 304L?
A: 304L reduces carbon from ≤0.08% to ≤0.03%, so chromium carbides do not precipitate at grain boundaries during welding or high-temperature (450–850 °C) service. Intergranular corrosion resistance is markedly better than 304 and post-weld annealing is normally unnecessary. Strength is slightly lower but ductility and toughness are higher. Prefer 304L for pressure equipment and welded structures.

## Stainless Steel 309S (UNS S30908)
URL: https://www.hb-nickelalloy.com/alloys/stainless-309s/
Family: Stainless Steel
Equivalents: DIN 1.4833; GB 06Cr23Ni13
Stainless 309S (UNS S30908) is a 23Cr-13Ni austenitic heat-resistant grade with carbon ≤ 0.08%. It resists oxidation and retains strength below 1000 °C and is widely used for furnace parts, automotive exhaust manifolds and as a buttering layer when joining dissimilar steels (carbon to stainless).
Composition (wt%): Fe Balance; Cr 22.0–24.0; Ni 12.0–15.0; Mn ≤ 2.00; Si ≤ 1.00; C ≤ 0.080; P ≤ 0.045; S ≤ 0.030
Mechanical (RT): tensile ≥ 515 MPa; yield ≥ 205 MPa; elongation ≥ 40 %; hardness ≤ 217 HB
Physical: density 7.98 g/cm³; melting 1398–1454 °C; thermal conductivity 15.6 W/m·K; modulus 200 GPa; max service 1000 °C (continuous oxidation)
Standards: ASTM A276; ASTM A240; ASTM A312; UNS S30908
Applications: Automotive exhaust manifolds and catalyst housings; Boiler burners and furnace structural parts; Transition layer in carbon-to-stainless clad plate; Annealing covers and heat-treat furnace internals; Cement and glass industry heat-resistant parts
Q: Can 309S filler metal replace 304/316 welding wire?
A: Not as a direct replacement. 309S's high Cr/Ni tolerates the higher heat input of dissimilar joining (carbon steel to stainless or stainless to heat-resistant steel) and is the preferred buttering and transition layer. When used to weld 304 or 316 base metal, the deposit chemistry far exceeds the parent, producing high residual stress and a different CTE, and the cost is unjustified. For same-grade welds use 308L (for 304 base) or 316L (for 316 base).

## Stainless Steel 310S (UNS S31008)
URL: https://www.hb-nickelalloy.com/alloys/stainless-310s/
Family: Stainless Steel
Equivalents: DIN 1.4845; GB 06Cr25Ni20
Stainless 310S (UNS S31008) is a 25Cr-20Ni high-chromium-nickel austenitic grade with carbon ≤ 0.08%. It has outstanding oxidation resistance and high-temperature strength below 1100 °C, making it the standard for furnace parts, heat-treat fixtures and radiant tubes.
Composition (wt%): Fe Balance; Cr 24.0–26.0; Ni 19.0–22.0; Mn ≤ 2.00; Si ≤ 1.50; C ≤ 0.080; P ≤ 0.045; S ≤ 0.030
Mechanical (RT): tensile ≥ 515 MPa; yield ≥ 205 MPa; elongation ≥ 40 %; hardness ≤ 217 HB
Physical: density 7.98 g/cm³; melting 1398–1454 °C; thermal conductivity 14.2 W/m·K; modulus 200 GPa; max service 1100 °C (continuous oxidation)
Standards: ASTM A276; ASTM A240; ASTM A312; ASTM A182; UNS S31008
Applications: Furnace rolls, radiant tubes and hearth rolls; Heat-treat fixtures and baskets; Petrochemical cracking and reformer tubes; Burner nozzles and high-temperature piping; Cement and metallurgical high-temperature parts
Q: How do I choose between 310S and 309S?
A: Both are 25Cr/20–22Ni heat-resistant grades. 310S has slightly higher nickel (~20%) and chromium (~25%) and a higher oxidation limit (~1100 °C) with better cyclic oxidation stability. 309S carries ~22% Ni and is typically used for 900–1000 °C furnace parts and automotive exhaust manifolds. Pick 310S for long-term service above 1000 °C or where higher creep life is required; 309S is fine for sub-950 °C service where weldability and cost matter more.

## Stainless Steel 316 (UNS S31600)
URL: https://www.hb-nickelalloy.com/alloys/stainless-316/
Family: Stainless Steel
Equivalents: DIN 1.4401; GB 06Cr17Ni12Mo2
Stainless 316 (UNS S31600) adds 2–3% molybdenum to 304, giving notably better pitting and crevice corrosion resistance in chloride, halide salt and seawater service. It is the workhorse austenitic grade for chemical, marine, pharmaceutical and pulp-and-paper industries.
Composition (wt%): Fe Balance; Cr 16.0–18.0; Ni 10.0–14.0; Mo 2.00–3.00; Mn ≤ 2.00; Si ≤ 1.00; C ≤ 0.080; P ≤ 0.045; S ≤ 0.030
Mechanical (RT): tensile ≥ 515 MPa; yield ≥ 205 MPa; elongation ≥ 40 %; hardness ≤ 217 HB
Physical: density 8.00 g/cm³; melting 1375–1400 °C; thermal conductivity 16.3 W/m·K; modulus 193 GPa; max service 800 °C
Standards: ASTM A276; ASTM A240; ASTM A312; ASTM A182; UNS S31600
Applications: Chemical piping and reaction vessels; Marine engineering and coastal structures; Pharmaceutical and biotech equipment; Pulp and paper bleaching equipment; Coastal buildings and bridges
Q: How do I choose between 316 and 316L?
A: Choose 316L (carbon ≤0.03%) for welded structures, long-term service in the 450–850 °C range, or where intergranular corrosion is a concern. Choose 316 for room-temperature load-bearing parts that are not heavily welded, where its slightly higher strength helps. In short: heavy welding → 316L; little welding → 316.

## Stainless Steel 316L (UNS S31603)
URL: https://www.hb-nickelalloy.com/alloys/stainless-316l/
Family: Stainless Steel
Equivalents: DIN 1.4404; GB 022Cr17Ni12Mo2
316L (UNS S31603) is a low-carbon austenitic stainless with 2–3% molybdenum, offering better pitting and intergranular corrosion resistance than 304. Low carbon (≤0.03%) removes weld sensitisation risk, making it the general-purpose choice for chemical, food, pharmaceutical and marine service.
Composition (wt%): Fe Balance; Cr 16.0–18.0; Ni 10.0–14.0; Mo 2.00–3.00; Mn ≤ 2.00; Si ≤ 0.75; C ≤ 0.030; P ≤ 0.045; S ≤ 0.030
Mechanical (RT): tensile ≥ 485 MPa; yield ≥ 170 MPa; elongation ≥ 40 %; hardness ≤ 217 HB
Physical: density 8.00 g/cm³; melting 1375–1400 °C; thermal conductivity 16.3 W/m·K; modulus 193 GPa; max service 800 °C
Standards: ASTM A276; ASTM A240; ASTM A312; ASTM A182; UNS S31603
Applications: Chemical piping, vessels and heat exchangers; Food and pharmaceutical clean equipment; Marine engineering and coastal architecture; Medical instruments and devices; Architectural cladding and decoration
Q: How long does 316L last in seawater?
A: 316L performs acceptably in flowing seawater, but is prone to pitting and crevice corrosion in stagnant seawater, crevices or hot (>60 °C) chloride service. With PREN around 26 it is a mid-range pitting grade. For higher reliability move to superaustenitic (904L / 254SMO), duplex 2205 or Inconel 625.
Q: What is the difference between 316 and 316L?
A: 316L limits carbon to 0.03% versus 0.08% for 316, so chromium carbides do not precipitate at grain boundaries during welding or high-temperature service. It therefore resists intergranular corrosion and normally needs no post-weld anneal. Strength is slightly lower, which can be offset by nitrogen alloying (316LN). Prefer 316L for pressure equipment and welded structures.

## Stainless Steel 904L (UNS N08904)
URL: https://www.hb-nickelalloy.com/alloys/stainless-904l/
Family: Stainless Steel
Equivalents: DIN 1.4539; GB 00Cr20Ni25Mo4.5Cu
904L (UNS N08904) is a high-nickel, high-molybdenum copper-bearing superaustenitic stainless with PREN around 36. It far outperforms 316L in dilute sulphuric and phosphoric acid and chloride media, with markedly better stress-corrosion-cracking resistance.
Composition (wt%): Fe Balance; Ni 23.0–28.0; Cr 19.0–23.0; Mo 4.00–5.00; Cu 1.00–2.00; Mn ≤ 2.00; Si ≤ 1.00; C ≤ 0.020
Mechanical (RT): tensile ≥ 490 MPa; yield ≥ 220 MPa; elongation ≥ 35 %; hardness ≤ 200 HB
Physical: density 8.00 g/cm³; melting 1300–1390 °C; thermal conductivity 12.0 W/m·K; modulus 195 GPa; max service 400 °C
Standards: ASTM B649; ASTM B625; ASTM B673; ASTM A240; UNS N08904
Applications: Sulphuric and phosphoric acid plant; Fertiliser and phosphate chemical units; Seawater cooling and desalination; Pulp, paper and pickling equipment; Pharmaceutical and fine-chemical vessels
Q: How does 904L compare economically with 316L?
A: 904L costs roughly 3–5 times 316L per kilogram but typically lasts several times longer in dilute sulphuric acid, phosphoric acid and chloride service. Where downtime is expensive and the medium aggressive, 904L has the lower life-cycle cost; for mild media such as clean water, steam or food-grade duties, 316L is more economical.

## Titanium Grade 12 (UNS R53400)
URL: https://www.hb-nickelalloy.com/alloys/titanium-grade-12/
Family: Titanium Alloys
Equivalents: DIN 3.7105; GB TA10
Titanium Grade 12 (UNS R53400, equivalent to TA10) replaces precious palladium with 0.3% molybdenum and 0.8% nickel, achieving corrosion resistance close to Grade 7 at lower cost and higher strength than Grade 2 — one of the best value corrosion resistant titanium grades.
Composition (wt%): Ti Balance; Mo 0.20–0.40; Ni 0.60–0.90; Fe ≤ 0.30; O ≤ 0.25; C ≤ 0.08
Mechanical (RT): tensile ≥ 483 MPa; yield ≥ 345 MPa; elongation ≥ 18 %; hardness ≤ 180 HB
Physical: density 4.51 g/cm³; melting 1630–1670 °C; thermal conductivity 16.6 W/m·K; modulus 103 GPa; max service 425 °C
Standards: ASTM B348; ASTM B265; ASTM B338; ASTM B381; UNS R53400
Applications: Chemical heat exchangers and evaporators; Desalination and brine equipment; Petrochemical condensing and cooling systems; FGD units
Q: Can Grade 12 fully replace Grade 7?
A: In most cases yes — Grade 12 approaches Grade 7 in reducing acids and hot chlorides while being stronger and cheaper. In the most severe high-temperature, high-concentration reducing-acid environments, Grade 7 still has more margin. Evaluate against actual concentration, temperature and crevice conditions.

## Titanium Grade 2 (UNS R50400)
URL: https://www.hb-nickelalloy.com/alloys/titanium-grade-2/
Family: Titanium Alloys
Equivalents: DIN 3.7035; GB TA2
Titanium Grade 2 (UNS R50400, equivalent to Chinese TA2) is the most widely used commercially pure titanium grade with at least 98.9% Ti. It combines excellent corrosion resistance with good formability and weldability, and is the standard material for chemical equipment, desalination and heat exchangers.
Composition (wt%): Ti Balance; Fe ≤ 0.30; O ≤ 0.25; C ≤ 0.08; N ≤ 0.03; H ≤ 0.015
Mechanical (RT): tensile ≥ 345 MPa; yield ≥ 275 MPa; elongation ≥ 20 %; hardness ≤ 160 HB
Physical: density 4.51 g/cm³; melting 1660–1675 °C; thermal conductivity 16.4 W/m·K; modulus 103 GPa; max service 425 °C
Standards: ASTM B348; ASTM B265; ASTM B338; ASTM B381; AMS 4902; UNS R50400
Applications: Chemical heat exchangers, reactors and columns; Desalination evaporators and condensers; Chlor-alkali and wet chlorine equipment; Marine and offshore piping; Surgical instruments and implant housings
Q: How does titanium Gr2 differ from 316L stainless in seawater?
A: 316L is prone to crevice and pitting corrosion in seawater and usually needs velocity limits and regular cleaning. Titanium Gr2 forms a stable TiO₂ passive film and is essentially uncorroded in seawater, salt spray and wet chlorine, tolerating velocities above 30 m/s without coatings. Life-cycle cost is usually lower.
Q: Why can't titanium be used in water-free methanol or fuming nitric acid?
A: Titanium relies on its surface oxide film. In strictly anhydrous reducing media such as dry methanol or dry chlorine, or in red fuming nitric acid with very high NOx, the film cannot be maintained and rapid corrosion or even pyrophoric reaction can occur. Use nickel alloys or run a dedicated evaluation for such service.

## Titanium Grade 23 (Ti-6Al-4V ELI) (UNS R56401)
URL: https://www.hb-nickelalloy.com/alloys/titanium-grade-23/
Family: Titanium Alloys
Equivalents: DIN 3.7165; GB TC4 ELI
Titanium Grade 23 (Ti-6Al-4V ELI, UNS R56401) is the extra-low-interstitial variant of Grade 5 with oxygen ≤ 0.13%. Higher fracture toughness and cryogenic toughness make it the international standard for orthopaedic and dental implants (ASTM F136 / ISO 5832-3).
Composition (wt%): Ti Balance; Al 5.50–6.50; V 3.50–4.50; Fe ≤ 0.25; O ≤ 0.13; C ≤ 0.08; N ≤ 0.05; H ≤ 0.0125
Mechanical (RT): tensile ≥ 828 MPa; yield ≥ 759 MPa; elongation ≥ 10 %; hardness ≈ 33 HRC
Physical: density 4.43 g/cm³; melting 1604–1660 °C; thermal conductivity 6.7 W/m·K; modulus 113 GPa; max service 350 °C
Standards: ASTM B348; ASTM B265; ASTM F136; AMS 4930; ISO 5832-3; UNS R56401
Applications: Artificial joints, bone plates and screws; Dental implants and orthodontic devices; Cryogenic pressure vessels and piping; Critical aerospace load-bearing parts; Cardiovascular stents and devices
Q: How does implant-grade TC4 ELI differ from standard TC4?
A: TC4 ELI (Grade 23) limits oxygen to 0.13% and iron to 0.25%, while standard TC4 (Grade 5) allows oxygen to 0.20%. Lower interstitial content yields higher fracture toughness and better cryogenic and fatigue performance — essential for implants under long-term cyclic load — and requires a fully traceable certificate to ASTM F136.

## Titanium Grade 5 (Ti-6Al-4V) (UNS R56400)
URL: https://www.hb-nickelalloy.com/alloys/titanium-grade-5/
Family: Titanium Alloys
Equivalents: DIN 3.7165; GB TC4
Titanium Grade 5 (Ti-6Al-4V, UNS R56400, equivalent to Chinese TC4) is the most widely used α+β titanium alloy, accounting for over half of global titanium consumption. It pairs high strength, low density and good corrosion resistance, and is the workhorse for aerospace structures and medical devices.
Composition (wt%): Ti Balance; Al 5.50–6.75; V 3.50–4.50; Fe ≤ 0.40; O ≤ 0.20; C ≤ 0.08; N ≤ 0.05; H ≤ 0.015
Mechanical (RT): tensile ≥ 895 MPa; yield ≥ 828 MPa; elongation ≥ 10 %; hardness ≈ 36 HRC
Physical: density 4.43 g/cm³; melting 1604–1660 °C; thermal conductivity 6.7 W/m·K; modulus 113 GPa; max service 400 °C
Standards: ASTM B348; ASTM B265; ASTM B338; ASTM B381; AMS 4928; UNS R56400
Applications: Aircraft structures, landing gear and engine parts; Orthopaedic and dental implants; Motorsport and premium bicycle components; High-pressure corrosion resistant chemical plant; Marine propellers and offshore parts; Sports equipment and eyewear frames
Q: How do I choose between Ti-6Al-4V and Grade 2?
A: Choose Grade 2 when corrosion resistance and formability matter most and strength demand is modest (heat exchangers, vessels, seawater piping). Choose Gr5 when strength and weight saving dominate (load-bearing structures, aerospace parts, implants). Gr5 is about 2.6 times stronger, but Gr2 forms and welds more easily and costs less.
Q: What is Ti-6Al-4V ELI and how does it differ from standard Grade 5?
A: ELI (Extra Low Interstitial) is Grade 23: oxygen is reduced from ≤0.20% to ≤0.13% and iron is lower, giving better fracture toughness, crack-growth resistance and cryogenic toughness. It is used for orthopaedic implants, cryogenic vessels and critical aerospace parts, with slightly lower strength than standard Grade 5.

## Titanium Grade 7 (UNS R52400)
URL: https://www.hb-nickelalloy.com/alloys/titanium-grade-7/
Family: Titanium Alloys
Equivalents: DIN 3.7235; GB TA9
Titanium Grade 7 (UNS R52400, equivalent to TA9) is Grade 2 with 0.12–0.25% palladium. The palladium markedly improves resistance to reducing acids and hot chlorides, giving crevice corrosion resistance far better than Grade 2.
Composition (wt%): Ti Balance; Pd 0.12–0.25; Fe ≤ 0.30; O ≤ 0.25; C ≤ 0.08; N ≤ 0.03
Mechanical (RT): tensile ≥ 345 MPa; yield ≥ 275 MPa; elongation ≥ 20 %; hardness ≤ 160 HB
Physical: density 4.51 g/cm³; melting 1660–1675 °C; thermal conductivity 16.0 W/m·K; modulus 103 GPa; max service 425 °C
Standards: ASTM B348; ASTM B265; ASTM B338; ASTM B381; UNS R52400
Applications: Dilute HCl and sulphuric acid chemical plant; High-temperature brine and seawater heat exchangers; Hydrometallurgy and electrolytic cells; Pulp bleaching equipment; Critical FGD components
Q: Is the extra cost of Grade 7 over Grade 2 justified?
A: In crevices, hot chlorides or reducing acids, Grade 7 often lasts several times longer than Grade 2, and downtime plus replacement cost far exceeds the material premium. For clean oxidising media or seawater, Grade 2 is sufficient and the palladium cost is unnecessary.