Hastelloy C-276 C-276 (UNS N10276)

Nickel-molybdenum-chromium-tungsten-iron alloy, UNS N10276. Haynes nominal composition in wt%: Ni 57 (balance), Cr 16, Mo 16, Fe 5, W 4

Also known as UNS N10276, UNS W10276, EN 2.4819, EN name NiMo16Cr15W, DIN 17744, ASTM B 574 · 14 more

Hastelloy C-276 (UNS N10276, W.Nr.

9 sources · Updated 2026-10-24 · CC BY 4.0

Evidence level

2 of 5

Lab-measured

Pitting and crevice attack

Above 150 C

Chloride stress cracking

No cracking in 1,008 hours

Acids, reducing and oxidising

0.17 to 0.53 mm/y

Strength at -196 C

965 MPa

Welding

0.13 mm/y

Recipe, share of the weight

  • Ni balance; Haynes nominal 57 wt%Nickel
  • Cr nominal; ATI typical 15.50Chromium
  • Mo nominal; ATI typical 16.0Molybdenum
  • W nominal; ATI typical 3.50Tungsten
  • Fe nominal; ATI typical 6.00Iron
  • Co 2.5 maximum (Haynes); ATI typical 0.10Cobalt
  • Mn 1 maximum (Haynes); ATI typical 0.150Manganese
  • V 0.35 maximum (Haynes); ATI typical 0.15Vanadium
  • Si 0.08 maximum (Haynes); ATI typical 0.03Silicon
  • C 0.01 maximum (Haynes); ATI typical 0.006Carbon
  • Cu 0.5 maximum (Haynes)Copper

Best for

Wet, mixed-acid and chloride service where a corrosion-resistant nickel alloy must also be welded and formed (Haynes; ATI)

Weakest at

Hot, concentrated nitric acid, where ATI says the chromium content is too low; Haynes gives 22.12 mm/y at the boil in 65 percent nitric acid

Risk at a glance

  • People Moderate. Nickel record flags hazards; pickling acid is severe
  • If it fails High. Attack by hot, concentrated nitric acid
  • Corrosion Severe. Corrosion rises steeply with heat in concentrated nitric acid: 0.41 mm/y at 66 C and 22.12 mm/y at the boil.

Quick facts: C-276 (UNS N10276)

Key properties of C-276 (UNS N10276)
PropertyValueBasis
Density8.89 to 8.9 g/cm³2 sourced values across conditions
Yield strength283 to 415 MPa4 sourced values across conditions
Tensile strength690 to 792 MPa4 sourced values across conditions
Young's modulus205 GPa1 sourced value
Thermal conductivity7.3 to 19 W/(m·K)4 sourced values across conditions
Thermal expansion (CTE)11.2 to 13.3 ppm/K2 sourced values across conditions
Melting point1,323 to 1,371 °C1 sourced value
Specific heat427 J/(kg·K)1 sourced value
Electrical resistivity0.0000012 to 0.0000013 Ω·m2 sourced values across conditions
Maximum service temperature677 °C1 sourced value

What is the density of Hastelloy C-276?

Hastelloy C-276 has a density of 8.89 to 8.9 g/cm³. The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.

What is the thermal conductivity of Hastelloy C-276?

Hastelloy C-276 has a thermal conductivity of 7.3 to 19 W/(m·K). The range covers 4 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.

What is the coefficient of thermal expansion of Hastelloy C-276?

Hastelloy C-276 has a coefficient of thermal expansion of 11.2 to 13.3 ppm/K. The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.

What is the melting point of Hastelloy C-276?

Hastelloy C-276 has a melting point of 1,323 to 1,371 °C. The source and test conditions are listed in the properties table on this page.

What is the yield strength of Hastelloy C-276?

Hastelloy C-276 has a yield strength of 283 to 415 MPa. The range covers 4 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.

What are the other names and codes for Hastelloy C-276?

Hastelloy C-276 is also written as UNS N10276, UNS W10276, EN 2.4819, EN name NiMo16Cr15W, DIN 17744, ASTM B 574. Each code is printed in the source listed beside it in the designations table.

What is Hastelloy C-276 used for?

Uses recorded in the sources include Reactors, heat exchangers and columns in chemical process plants; Outlet ducting in flue-gas desulfurization systems; Off-gas line and condensate storage tank for nuclear-waste vitrification (Savannah River Plant).

Why it exists

Hastelloy C-276 is chosen where a nickel alloy must resist mixed acids and chloride solutions and still be welded and formed. Haynes says its extremely low carbon and silicon contents are why it alleviates concerns over welding, and ATI says the alloy keeps a high level of corrosion resistance in the welded condition. Its nickel and molybdenum give extreme resistance to chloride stress-corrosion cracking (ATI). Its limits are the most strongly oxidising acids, and its high-temperature data are thin: the sources print code temperature limits and an oxidation remark, but no creep or rupture numbers. Haynes International's first Hastelloy alloy dates from 1922 (Wikipedia).

Where it's used

Chemical plants

Haynes names reactors, heat exchangers and columns as typical chemical process uses. ATI calls the alloy widely used in chemical and petrochemical processing.

Flue-gas desulfurization

ATI names outlet ducting in the more corrosive part of flue-gas desulfurization systems. In its boiling Green Death scrubber test ATI 276 gives 26.5 mpy (0.67 mm/a), while Type 316 is destroyed.

Nuclear-waste processing

ATI says over 1,000 tons of UNS N10276 alloy went into a vitrification off-gas line and condensate tank at the Savannah River Plant, after the alloy passed a 10-day test.

Sour oil and gas

Haynes lists the alloy under NACE MR0175 and says it is very resistant to sulfide stress cracking in sour oilfield environments.

Recipe

Nickel-molybdenum-chromium-tungsten-iron alloy, UNS N10276. Haynes nominal composition in wt%: Ni 57 (balance), Cr 16, Mo 16, Fe 5, W 4; maximum limits Co 2.5, Mn 1, V 0.35, Si 0.08, C 0.01, Cu 0.5. ATI typical composition in wt% (typical values, not limits): Ni balance, Cr 15.50, Mo 16.0, W 3.50, Fe 6.00, Co 0.10, Mn 0.150, V 0.15, Si 0.03, C 0.006, P 0.005, S 0.002.

Hastelloy C-276 is a wrought nickel alloy with molybdenum, chromium and tungsten additions and very low carbon and silicon. Haynes gives the nominal composition in weight percent, and ATI gives a typical composition that differs slightly. The fetched sources do not describe how the alloy is melted. They describe the wrought forms it is sold in (plates, sheets, strips, billets, bars, wires, pipes, tubes and covered electrodes) and its solution anneal.

What C-276 (UNS N10276) is made of
IngredientShare of the weightWhat it does
Nickel Ni balance; Haynes nominal 57 wt% Matrix of the alloy. With molybdenum it gives extreme resistance to chloride stress-corrosion cracking (ATI).
Chromium Cr nominal; ATI typical 15.50 Gives resistance to oxidising conditions, but ATI says it is too low for hot concentrated nitric acid.
Molybdenum Mo nominal; ATI typical 16.0 Gives resistance to pitting and crevice attack and to non-oxidising acids (Haynes; ATI).
Tungsten W nominal; ATI typical 3.50 Adds to the pitting resistance that chromium and molybdenum give (ATI).
Iron Fe nominal; ATI typical 6.00 Present in the nominal composition; the fetched sources give it no role.
Cobalt Co 2.5 maximum (Haynes); ATI typical 0.10 Present up to the maximum; the fetched sources give it no role.
Manganese Mn 1 maximum (Haynes); ATI typical 0.150 Present up to the maximum; the fetched sources give it no role.
Vanadium V 0.35 maximum (Haynes); ATI typical 0.15 Present up to the maximum; the fetched sources give it no role.
Silicon Si 0.08 maximum (Haynes); ATI typical 0.03 Kept very low: Haynes ties the low silicon and carbon to easier welding, and ATI warns that raising them may adversely affect properties.
Carbon C 0.01 maximum (Haynes); ATI typical 0.006 Kept very low for welding; ATI warns that raising it may adversely affect properties.
Copper Cu 0.5 maximum (Haynes) Present up to the maximum; the fetched sources give it no role.

Weight shares are as printed in the sources.

What it can do

Pitting and crevice attack

Above 150 C

Haynes gives a critical pitting temperature above 150 C in acidified ferric chloride (ASTM G 48), against 100 C for alloy 625 and 15 C for 316L.

Chloride stress cracking

No cracking in 1,008 hours

Haynes reports no cracking in 1,008 hours in boiling 45 percent magnesium chloride. ATI reports resistance for 1000 hours in boiling 42 percent magnesium chloride.

Acids, reducing and oxidising

0.17 to 0.53 mm/y

Haynes gives 0.17 mm/y in 10 percent hydrochloric acid at 38 C and 0.18 mm/y in boiling 10 percent sulfuric acid. Chromic acid at 20 percent and 66 C gives 0.53 mm/y.

Strength at -196 C

965 MPa

ATI's typical tensile test gives 965 MPa at -196 C with 45 percent elongation, after annealing at 2100 F and water quenching.

Welding

0.13 mm/y

Haynes says the alloy is very amenable to GTAW, GMAW and SMAW welding. Weld metal in 70 percent sulfuric acid at 66 C corrodes at 0.13 mm/y.

How it compares

Compare with [Inconel 625](/profiles/inconel-625/), the other nickel alloy in this family. Haynes says C-276 gives much greater resistance than alloy 625 to higher concentrations of hydrochloric and sulfuric acid. In the ferric chloride test, Haynes gives alloy 625 a critical pitting temperature of 100 C, against more than 150 C for C-276.

The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details. Other materials are shown beside it; each was measured under its own conditions, so open its page before comparing closely. Compare every grade in the family.

Benchmarks
MeasurementC-276 (UNS N10276)IN718 (UNS N07718)IN625 (UNS N06625)FeNi36Ni-MoC-22X (UNS N06002)UNS N07214H230 (UNS N06230)UNS N08800Alloy 825 (UNS N08825)Alloy 600 (UNS N06600, W.Nr. 2.4816)Alloy 601Alloy 617X-750 (UNS N07750)Fe-Ni-CoAlloy 400 (UNS N04400)K-500NiNi3Al, NiAlNiBe2Ni-alloysUNS N07090 (W. Nr. 2.4632)UNS N07001
Capacity and energy
Charpy V-notch impact energyHaynes Impact Strength table, RT row, J column479 J19no datano datano data479 J469 J140 Jno datano data122 Jno data82.4 Jno datano datano datano datano datano datano datano datano datano datano datano data
Charpy V-notch impact energy519 J20no datano datano data479 J469 J140 Jno datano data122 Jno data82.4 Jno datano datano datano datano datano datano datano datano datano datano datano data
Charpy V-notch impact energy, full thickness245 J38no datano datano data479 J469 J140 Jno datano data122 Jno data82.4 Jno datano datano datano datano datano datano datano datano datano datano datano data
Charpy V-notch impact energy, full thickness325 J39no datano datano data479 J469 J140 Jno datano data122 Jno data82.4 Jno datano datano datano datano datano datano datano datano datano datano datano data
Thermal behavior and safety
melting point1323 to 1371 °C21260 °C1290 to 1350 °C1427 °C1370 to 1418 °C1357 to 1399 °C1260 to 1355 °C1355 to 1400 °C1301 to 1371 °C1357 to 1385 °C1370 to 1400 °C1354 to 1413 °C1360 to 1411 °C1330 to 1380 °C1393 to 1427 °C1450 °C1300 to 1350 °C1315 to 1350 °C1455 °Cno data1195 to 1325 °C1425 °C1370 °C1330 to 1360 °C
Thermal conductivity10.5 W/m.°C479 BTU·in/ft²·h·°F9.8 W/m°C72.85 Btu·in/(hr·ft²·°F)11.2 W/m.°C10.1 W/(m·K)9.2 W/(m·K)12 W/m-°C8.9 W/(m·°C)11.5 W/m°C11.1 W/(m·K)14.9 W/(m·K)11.2 W/(m·K)13.4 W/(m·K)83 Btu/in./hr/sq ft/°F17.5 W/m °K22 W/m°C17.5 W/m °C70.3 W/(m·K)no data48 W/(m·K)13 W/(m·K)11.47 W/(m·K)19.1 W/(m·°C)
Thermal conductivity18.3 W/m.°C579 BTU·in/ft²·h·°F9.8 W/m°C72.85 Btu·in/(hr·ft²·°F)11.2 W/m.°C10.1 W/(m·K)9.2 W/(m·K)12 W/m-°C8.9 W/(m·°C)11.5 W/m°C11.1 W/(m·K)14.9 W/(m·K)11.2 W/(m·K)13.4 W/(m·K)83 Btu/in./hr/sq ft/°F17.5 W/m °K22 W/m°C17.5 W/m °C70.3 W/(m·K)no data48 W/(m·K)13 W/(m·K)11.47 W/(m·K)19.1 W/(m·°C)
specific heat427 J/kg.°C8435 J/kg °C410 J/(kg·K)515 J/(kg·K)373 J/kg.°C410 J/(kg·K)486 J/(kg·K)452 J/kg-°C397 J/kg·°C460 J/kg·°C440 J/(kg·K)444 J/kg °C448 J/(kg·K)419 J/(kg·K)0.103 Btu/lb/°F500 J/(kg. K)427 J/kg°C419 J/kg °C456 J/(kg·K)no datano data500 J/(kg·K)446 J/(kg·K)no data
Thermal conductivity7.3 W/m•K2679 BTU·in/ft²·h·°F9.8 W/m°C72.85 Btu·in/(hr·ft²·°F)11.2 W/m.°C10.1 W/(m·K)9.2 W/(m·K)12 W/m-°C8.9 W/(m·°C)11.5 W/m°C11.1 W/(m·K)14.9 W/(m·K)11.2 W/(m·K)13.4 W/(m·K)83 Btu/in./hr/sq ft/°F17.5 W/m °K22 W/m°C17.5 W/m °C70.3 W/(m·K)no data48 W/(m·K)13 W/(m·K)11.47 W/(m·K)19.1 W/(m·°C)
Thermal conductivity19 W/m•K2779 BTU·in/ft²·h·°F9.8 W/m°C72.85 Btu·in/(hr·ft²·°F)11.2 W/m.°C10.1 W/(m·K)9.2 W/(m·K)12 W/m-°C8.9 W/(m·°C)11.5 W/m°C11.1 W/(m·K)14.9 W/(m·K)11.2 W/(m·K)13.4 W/(m·K)83 Btu/in./hr/sq ft/°F17.5 W/m °K22 W/m°C17.5 W/m °C70.3 W/(m·K)no data48 W/(m·K)13 W/(m·K)11.47 W/(m·K)19.1 W/(m·°C)
Physical and electrical
Density8.89 g/cm³10.297 lb/in38.44 g/cm³8.05 g/cm³9.22 g/cm³8.69 g/cm³8.22 g/cm³8.05 g/cm³8.97 g/cm³7.94 g/cm³8.14 g/cm³0.306 lb/in38.11 Mg/m38.36 g/cm³8.28 g/cm³8.36 g/cm³8.8 g/cm³8.45 g/cm³8.89 g/cm³7.5 g/cm³8.27 g/cm³8.2 g/cm³8.18 g/cm³8.19 g/cm³
electrical resistivity1.23 μohm.m3725 ohm circ mil/ft129 µΩ-cm84 µΩ·cm1.37 μohm.m1.14 µΩ·m114.8 µohm-cm135.9 µohm-cm125 µohm-m0.989 µΩ·m112 µΩ·cm1.03 µΩ·m1.18 µΩ·m1.22×10^-4 Ω·cm731 ohm circ mil/ft49 μΩcm0.511 µΩ·m0.615 µΩ·m0.096 µΩ·mno data< 28.7 µΩ·cm45 µΩ·cm1.18 µΩ·m1.24 µΩ·m
Rockwell B hardness, tungsten indenter (HRBW)Haynes Hardness table, Sheet row88 HRBWno datano datano datano datano data87 HRBWno datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano data
Rockwell B hardness, tungsten indenter (HRBW)Haynes Hardness table, Bar row86 HRBWno datano datano datano datano data87 HRBWno datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano data
Density8.9 g/cm³240.297 lb/in38.44 g/cm³8.05 g/cm³9.22 g/cm³8.69 g/cm³8.22 g/cm³8.05 g/cm³8.97 g/cm³7.94 g/cm³8.14 g/cm³0.306 lb/in38.11 Mg/m38.36 g/cm³8.28 g/cm³8.36 g/cm³8.8 g/cm³8.45 g/cm³8.89 g/cm³7.5 g/cm³8.27 g/cm³8.2 g/cm³8.18 g/cm³8.19 g/cm³
electrical resistivity130 microhm-cm25725 ohm circ mil/ft129 µΩ-cm84 µΩ·cm1.37 μohm.m1.14 µΩ·m114.8 µohm-cm135.9 µohm-cm125 µohm-m0.989 µΩ·m112 µΩ·cm1.03 µΩ·m1.18 µΩ·m1.22×10^-4 Ω·cm731 ohm circ mil/ft49 μΩcm0.511 µΩ·m0.615 µΩ·m0.096 µΩ·mno data< 28.7 µΩ·cm45 µΩ·cm1.18 µΩ·m1.24 µΩ·m
Temperature behavior
Critical pitting temperature in acidified 6% ferric chloride> 150 °C22no datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano data
Critical crevice temperature in acidified 6% ferric chloride55 °C23no datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano datano data
Other measurements
Thermal expansion (CTE)11.2 μm/m.°C68.91 ppm/°F12.8 ppm/°C1.3 ppm/K10.6 μm/m.°C12.4 ppm/K13.9 µm/(m·K)14.6 µm/m-°C11.8 ppm/K14.4 µm/m/°C13.9 ppm/K10.4 ppm/K13.75 µm/m/°C11.6 µm/(m·K)7 10-6 in./in./°F5.86 10-6/°C14.2 µm/m°C13.7 10-6/°C13.3 ppm/Kno data14.5 ppm/K8 ppm/K12.7 µm/(m·K)14.3 µm/m·°C
Thermal expansion (CTE)13.3 μm/m.°C78.91 ppm/°F12.8 ppm/°C1.3 ppm/K10.6 μm/m.°C12.4 ppm/K13.9 µm/(m·K)14.6 µm/m-°C11.8 ppm/K14.4 µm/m/°C13.9 ppm/K10.4 ppm/K13.75 µm/m/°C11.6 µm/(m·K)7 10-6 in./in./°F5.86 10-6/°C14.2 µm/m°C13.7 10-6/°C13.3 ppm/Kno data14.5 ppm/K8 ppm/K12.7 µm/(m·K)14.3 µm/m·°C
elastic modulus205 GPa929 ksi x 10^3207.5 GPa140 GPa216 GPa206 GPa205 GPa218 GPa209 GPa196.5 GPa196 GPa214 GPa206.5 GPa211 GPa31 10^3 ksi138 kN/mm226 10^3 ksi179 GPa205 GPa200 GPa195 to 210 GPano data204 GPa211 GPa
elastic modulus178 GPa1029 ksi x 10^3207.5 GPa140 GPa216 GPa206 GPa205 GPa218 GPa209 GPa196.5 GPa196 GPa214 GPa206.5 GPa211 GPa31 10^3 ksi138 kN/mm226 10^3 ksi179 GPa205 GPa200 GPa195 to 210 GPano data204 GPa211 GPa
poissons ratio0.31 -110.294 -0.278 -no datano datano data0.32 -no data0.31 -0.339 -no data0.324 -0.272 -no data0.29 -no data0.32 -no datano datano data0.3 -no datano datano data
yield strength356 MPa12171 ksi60 to 95 ksi40 ksi421 MPa> 310 MPa340 MPa577 MPa417 MPa250 MPa338 MPa170 to 345 MPa292 MPa340 MPa> 105 ksi> 200 N/mm225 to 50 ksi276 to 414 MPa105 to 210 MPano data280 to 480 MPa280 MPa752 MPa586 MPa
ultimate tensile strength792 MPa13201 ksi120 to 150 ksi65 ksi862 MPa690 to 950 MPa760 MPa975 MPa837 MPa590 MPa662 MPa550 to 690 MPa675 MPa710 MPa> 165 ksi450 to 585 N/mm275 to 90 ksi621 to 758 MPa380 to 520 MPa2300 MPa660 to 900 MPa500 MPa1175 MPa1027 MPa
elongation61 %1426 %30 to 60 %35 %53 %> 45 %48.9 %37.3 %47.3 %17 %45 %35 to 55 %46 %62 %> 20 %> 25 %35 to 60 %20 to 35 %40 to 55 %no data> 30 %35 %30 %43 %
yield strength365 MPa15171 ksi60 to 95 ksi40 ksi421 MPa> 310 MPa340 MPa577 MPa417 MPa250 MPa338 MPa170 to 345 MPa292 MPa340 MPa> 105 ksi> 200 N/mm225 to 50 ksi276 to 414 MPa105 to 210 MPano data280 to 480 MPa280 MPa752 MPa586 MPa
ultimate tensile strength785 MPa16201 ksi120 to 150 ksi65 ksi862 MPa690 to 950 MPa760 MPa975 MPa837 MPa590 MPa662 MPa550 to 690 MPa675 MPa710 MPa> 165 ksi450 to 585 N/mm275 to 90 ksi621 to 758 MPa380 to 520 MPa2300 MPa660 to 900 MPa500 MPa1175 MPa1027 MPa
yield strength225 MPa17171 ksi60 to 95 ksi40 ksi421 MPa> 310 MPa340 MPa577 MPa417 MPa250 MPa338 MPa170 to 345 MPa292 MPa340 MPa> 105 ksi> 200 N/mm225 to 50 ksi276 to 414 MPa105 to 210 MPano data280 to 480 MPa280 MPa752 MPa586 MPa
ultimate tensile strength650 MPa18201 ksi120 to 150 ksi65 ksi862 MPa690 to 950 MPa760 MPa975 MPa837 MPa590 MPa662 MPa550 to 690 MPa675 MPa710 MPa> 165 ksi450 to 585 N/mm275 to 90 ksi621 to 758 MPa380 to 520 MPa2300 MPa660 to 900 MPa500 MPa1175 MPa1027 MPa
Maximum service temperature677 °C211300 °F982 °Cno datano datano datano data1260 °Cno datano datano datano data1000 °Cno data1200 °Fno datano data650 °Cno data1373 Kno datano datano data650 °C
yield strength> 283 MPa28171 ksi60 to 95 ksi40 ksi421 MPa> 310 MPa340 MPa577 MPa417 MPa250 MPa338 MPa170 to 345 MPa292 MPa340 MPa> 105 ksi> 200 N/mm225 to 50 ksi276 to 414 MPa105 to 210 MPano data280 to 480 MPa280 MPa752 MPa586 MPa
ultimate tensile strength> 690 MPa29201 ksi120 to 150 ksi65 ksi862 MPa690 to 950 MPa760 MPa975 MPa837 MPa590 MPa662 MPa550 to 690 MPa675 MPa710 MPa> 165 ksi450 to 585 N/mm275 to 90 ksi621 to 758 MPa380 to 520 MPa2300 MPa660 to 900 MPa500 MPa1175 MPa1027 MPa
elongation> 40 %3026 %30 to 60 %35 %53 %> 45 %48.9 %37.3 %47.3 %17 %45 %35 to 55 %46 %62 %> 20 %> 25 %35 to 60 %20 to 35 %40 to 55 %no data> 30 %35 %30 %43 %
yield strength565 MPa31171 ksi60 to 95 ksi40 ksi421 MPa> 310 MPa340 MPa577 MPa417 MPa250 MPa338 MPa170 to 345 MPa292 MPa340 MPa> 105 ksi> 200 N/mm225 to 50 ksi276 to 414 MPa105 to 210 MPano data280 to 480 MPa280 MPa752 MPa586 MPa
ultimate tensile strength965 MPa32201 ksi120 to 150 ksi65 ksi862 MPa690 to 950 MPa760 MPa975 MPa837 MPa590 MPa662 MPa550 to 690 MPa675 MPa710 MPa> 165 ksi450 to 585 N/mm275 to 90 ksi621 to 758 MPa380 to 520 MPa2300 MPa660 to 900 MPa500 MPa1175 MPa1027 MPa
elongation45 %3326 %30 to 60 %35 %53 %> 45 %48.9 %37.3 %47.3 %17 %45 %35 to 55 %46 %62 %> 20 %> 25 %35 to 60 %20 to 35 %40 to 55 %no data> 30 %35 %30 %43 %
yield strength415 MPa34171 ksi60 to 95 ksi40 ksi421 MPa> 310 MPa340 MPa577 MPa417 MPa250 MPa338 MPa170 to 345 MPa292 MPa340 MPa> 105 ksi> 200 N/mm225 to 50 ksi276 to 414 MPa105 to 210 MPano data280 to 480 MPa280 MPa752 MPa586 MPa
ultimate tensile strength790 MPa35201 ksi120 to 150 ksi65 ksi862 MPa690 to 950 MPa760 MPa975 MPa837 MPa590 MPa662 MPa550 to 690 MPa675 MPa710 MPa> 165 ksi450 to 585 N/mm275 to 90 ksi621 to 758 MPa380 to 520 MPa2300 MPa660 to 900 MPa500 MPa1175 MPa1027 MPa
yield strength270 MPa36171 ksi60 to 95 ksi40 ksi421 MPa> 310 MPa340 MPa577 MPa417 MPa250 MPa338 MPa170 to 345 MPa292 MPa340 MPa> 105 ksi> 200 N/mm225 to 50 ksi276 to 414 MPa105 to 210 MPano data280 to 480 MPa280 MPa752 MPa586 MPa
ultimate tensile strength640 MPa37201 ksi120 to 150 ksi65 ksi862 MPa690 to 950 MPa760 MPa975 MPa837 MPa590 MPa662 MPa550 to 690 MPa675 MPa710 MPa> 165 ksi450 to 585 N/mm275 to 90 ksi621 to 758 MPa380 to 520 MPa2300 MPa660 to 900 MPa500 MPa1175 MPa1027 MPa

Why choose it, and why not

Good for

  • Wet and mixed-acid service, such as reactors, columns and heat exchangers in chemical plants (Haynes; ATI).
  • Flue-gas desulfurization ducting in the more corrosive areas, where ATI says the alloy is used (ATI).
  • Seawater and brine service, where ATI calls the alloy inert to seawater and Haynes reports a maximum crevice depth of 0.13 mm after 180 days.

Watch out for

  • Hot, concentrated nitric acid: Haynes reports 22.12 mm/y in boiling 65 percent nitric acid, and ATI says the alloy is not suited to it.
  • Long exposure at high temperature: ATI says the alloy eventually forms embrittling precipitates. No time or temperature is printed.
  • Cold work: Haynes says it can affect stress-corrosion resistance, so re-anneal after 7 percent or more outer-fibre elongation.
  • Strength falls with heat: ATI's typical yield strength falls from 415 MPa at 21 C to 270 MPa at 538 C.
  • The corrosion numbers are laboratory results in reagent-grade acids (Haynes) or typical test results (ATI), not field data.

Hastelloy C-276 suits mixed acids and chloride service, and it keeps much of its corrosion resistance through welding when it is properly annealed. Keep it out of hot concentrated nitric acid, and follow the anneal and re-anneal steps.

Technical details

For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.

Other names and standards

The same grade under other systems, as datasheets and standards print them. Each code was checked against the page it comes from.

Other names and standards
SystemCodes
UNSN10276, W10276 (welding filler metal form, printed beside N10276)
EN2.4819
EN nameNiMo16Cr15W
DIN17744
ASTMB 574 (billet, rod and bar), B 575 (sheet, plate and strip), B 619 (welded pipe and tube), B 622 (seamless pipe and tube), B 626 (welded tube), B 366 (fittings), B 564 (forgings), B 983 (seamless pipe and tube)
ASMESB 574 (billet, rod and bar), SB 575 (sheet, plate and strip), SB 619 (welded pipe and tube), SB 622 (seamless pipe and tube)
NACEMR0175 (sour-service listing)
Trade nameHASTELLOY® C-276, ATI 276

Notes

The method, full conditions and any caveat for the numbered rows above.

Notes for the numbered rows
#MeasurementMethodConditionsCaveat
1DensityHaynes Physical Properties table, Density row at room temperature, metric columntemperature room temperaturebasis metric column of the physical properties table; 0.321 lb/in3 is printed alongside—
2melting pointHaynes Physical Properties table, Melting Range row, metric columnbasis melting range, metric column; 2415 to 2500 F is printed alongside—
3electrical resistivityHaynes Physical Properties table, Electrical Resistivity, RT row, metric columntemperature room temperaturebasis 48.4 μohm.in is printed alongside—
4Thermal conductivityHaynes Physical Properties table, Thermal Conductivity, 50 °C rowtemperature 50 °Cbasis metric column; the British column lists other temperatures—
5Thermal conductivityHaynes Physical Properties table, Thermal Conductivity, 500 °C rowtemperature 500 °Cbasis metric column—
6Thermal expansion (CTE)Haynes Physical Properties table, Mean Coefficient of Thermal Expansion, 24-100 °C row, metric columntemperature range 24 to 100 °Cbasis mean coefficient of thermal expansion from 24 °C—
7Thermal expansion (CTE)Haynes Physical Properties table, Mean Coefficient of Thermal Expansion, 24-500 °C row, metric columntemperature range 24 to 500 °Cbasis mean coefficient of thermal expansion from 24 °C—
8specific heatHaynes Physical Properties table, Specific Heat, RT rowtemperature room temperaturebasis metric column; 0.102 Btu/lb.°F is printed alongside—
9elastic modulusHaynes Physical Properties table, Dynamic Modulus of Elasticity, RT row, metric columntemperature room temperaturebasis printed as dynamic modulus of elasticity—
10elastic modulusHaynes Physical Properties table, Dynamic Modulus of Elasticity, 500 °C row, metric columntemperature 500 °Cbasis printed as dynamic modulus of elasticity—
11poissons ratioHaynes Physical Properties table, Poisson's Ratio, RT rowtemperature room temperature—
12yield strengthHaynes Tensile Strength and Elongation table, Sheet row at RT, MPa column; 51.6 ksi is printed alongsidecondition mill annealed, which Haynes describes as the solution anneal (supply condition; the table does not restate it)product sheet, 2 mm (0.078 in) thicktemperature room temperatureoffset 0.2 percent—
13ultimate tensile strengthHaynes Tensile Strength and Elongation table, Sheet row at RT, MPa column; 114.9 ksi is printed alongsidecondition mill annealed, the solution anneal (supply condition)product sheet, 2 mm (0.078 in) thicktemperature room temperature—
14elongationHaynes Tensile Strength and Elongation table, Sheet row at RTcondition mill annealed, the solution anneal (supply condition)product sheet, 2 mm (0.078 in) thicktemperature room temperature—
15yield strengthHaynes Tensile Strength and Elongation table, Plate row at RT, MPa column; 52.9 ksi is printed alongsidecondition mill annealed, the solution anneal (supply condition)product plate, 25.4 mm (1 in) thicktemperature room temperatureoffset 0.2 percent—
16ultimate tensile strengthHaynes Tensile Strength and Elongation table, Plate row at RT, MPa column; 113.9 ksi is printed alongsidecondition mill annealed, the solution anneal (supply condition)product plate, 25.4 mm (1 in) thicktemperature room temperature—
17yield strengthHaynes Tensile Strength and Elongation table, Sheet row at 800 F (427 C), MPa column; 32.7 ksi is printed alongsidecondition mill annealed, the solution anneal (supply condition)product sheet, 2 mm (0.078 in) thicktemperature 427 °C (800 °F)offset 0.2 percent—
18ultimate tensile strengthHaynes Tensile Strength and Elongation table, Sheet row at 800 F (427 C), MPa column; 94.3 ksi is printed alongsidecondition mill annealed, the solution anneal (supply condition)product sheet, 2 mm (0.078 in) thicktemperature 427 °C (800 °F)—
19Charpy V-notch impact energy—temperature room temperaturespecimen Charpy V-notch, mill annealed platebasis 353 ft-lbf is printed alongside—
20Charpy V-notch impact energyHaynes Impact Strength table, -320 F row, J columntemperature -196 °C (-320 °F)specimen Charpy V-notch, mill annealed platebasis 383 ft-lbf is printed alongside—
21Maximum service temperatureHaynes Specifications and Codes page, Codes table, ASME Section VIII rowbasis code approval: ASME Section VIII Div. 1 and Div. 2 approve 1250 F (677 C) for plate, sheet, bar, forgings, fittings and pipe; ASME B31.3 also 1250 Fcondition product forms as listed in the approval footnotesA code approval temperature, not a test result. The brochure gives lower code limits for other codes, for example 1000 F for ASME Section I.
22Critical pitting temperature in acidified 6% ferric chlorideHaynes Resistance to Pitting and Crevice Corrosion table, C-276 rowtest ASTM G 48 in acidified 6 wt% ferric chloride; lowest temperature for attack within 72 hoursbasis printed as >150 C (>302 F)—
23Critical crevice temperature in acidified 6% ferric chlorideHaynes Resistance to Pitting and Crevice Corrosion table, C-276 rowtest ASTM G 48 in acidified 6 wt% ferric chloride; within 72 hoursbasis printed as 131 F—
24DensityATI TDS, Physical Properties, Density; 0.321 lb/in3 is printed alongsidebasis typical value; temperature not statedATI prints 8.90 and Haynes prints 8.89. Both are kept with their own sources.
25electrical resistivityATI TDS, Physical Properties, Electrical Resistivitytemperature 70 F (21 C)basis typical valueHaynes prints 1.23 μohm.m at room temperature in a different unit. Both values are kept as printed.
26Thermal conductivityATI TDS, Thermal Conductivity table, -270 F row, W/m K columntemperature -168 °C (-270 °F)basis typical value; no test condition printed in the table—
27Thermal conductivityATI TDS, Thermal Conductivity table, 1000 F row, W/m K columntemperature 538 °C (1000 °F)basis typical value; no test condition printed in the table—
28yield strengthATI TDS, Minimum Properties (ASTM B 575) table; 41,000 psi (283 MPa) is printedspecification ASTM B 575 minimum for plate, sheet and strip, as printed by ATIcondition solution-annealed (ATI: all forms are furnished solution-annealed)temperature room temperatureoffset 0.2 percentSpecification minimum, not a typical value.
29ultimate tensile strengthATI TDS, Minimum Properties (ASTM B 575) table; 100,000 psi (690 MPa) is printedspecification ASTM B 575 minimum for plate, sheet and strip, as printed by ATIcondition solution-annealed (ATI: all forms are furnished solution-annealed)temperature room temperatureSpecification minimum, not a typical value.
30elongationATI TDS, Minimum Properties (ASTM B 575) table; elongation in 2 inch, minimum 40 percentspecification ASTM B 575 minimum for plate, sheet and strip, as printed by ATIcondition solution-annealed (ATI: all forms are furnished solution-annealed)gauge 2 inchSpecification minimum, not a typical value.
31yield strengthATI TDS, short-time tensile table, -320 F row, 0.2 percent yield, MPatemperature -196 °C (-320 °F)condition annealed at 2100 F (1150 C) and water quenched (ATI test material)basis typical short-time tensile valueoffset 0.2 percent—
32ultimate tensile strengthATI TDS, short-time tensile table, -320 F row, tensile strength, MPatemperature -196 °C (-320 °F)condition annealed at 2100 F (1150 C) and water quenched (ATI test material)basis typical short-time tensile value—
33elongationATI TDS, short-time tensile table, -320 F row, elongationtemperature -196 °C (-320 °F)condition annealed at 2100 F (1150 C) and water quenched (ATI test material)basis typical short-time tensile value—
34yield strengthATI TDS, short-time tensile table, 70 F row, 0.2 percent yield, MPatemperature 21 °C (70 °F)condition annealed at 2100 F (1150 C) and water quenched (ATI test material)basis typical short-time tensile valueoffset 0.2 percent—
35ultimate tensile strengthATI TDS, short-time tensile table, 70 F row, tensile strength, MPatemperature 21 °C (70 °F)condition annealed at 2100 F (1150 C) and water quenched (ATI test material)basis typical short-time tensile value—
36yield strengthATI TDS, short-time tensile table, 1000 F row, 0.2 percent yield, MPatemperature 538 °C (1000 °F)condition annealed at 2100 F (1150 C) and water quenched (ATI test material)basis typical short-time tensile valueoffset 0.2 percent—
37ultimate tensile strengthATI TDS, short-time tensile table, 1000 F row, tensile strength, MPatemperature 538 °C (1000 °F)condition annealed at 2100 F (1150 C) and water quenched (ATI test material)basis typical short-time tensile value—
38Charpy V-notch impact energy, full thicknessATI TDS, Impact Resistant table, -320 F row, Joules columntemperature -196 °C (-320 °F)specimen full thickness 10 mm sample from annealed platebasis 180 ft-lbs is printed alongside—
39Charpy V-notch impact energy, full thicknessATI TDS, Impact Resistant table, 70 F row, Joules columntemperature 21 °C (70 °F)specimen full thickness 10 mm sample from annealed platebasis 240 ft-lbs is printed alongside—

Corrosion and compatibility

What happens when it meets other materials and environments.

Corrosion and compatibility
EnvironmentConcernWhat happens
Nitric acid, 65 wt%, at 66 C to the boil (strongly oxidising) severe Corrosion rises steeply with heat in concentrated nitric acid: 0.41 mm/y at 66 C and 22.12 mm/y at the boil.1
Chromic acid, 20 wt%, at 66 C (oxidising) severe Chromic acid at 66 C corrodes the alloy at 0.53 mm/y.2
Hydrochloric acid, 10 wt%, at 38 C (reducing) moderate Dilute hydrochloric acid at 38 C gives 0.17 mm/y.3
Hydrochloric acid, 5 wt%, at the boil (reducing) severe Boiling 5 percent hydrochloric acid corrodes at 3.63 mm/y.4
Sulfuric acid, 10 wt%, at the boil (reducing) moderate Boiling 10 percent sulfuric acid gives 0.18 mm/y.5
Sulfuric acid, 60 wt%, at the boil (reducing) severe Concentrated sulfuric acid at the boil corrodes at 13.08 mm/y.6
Phosphoric acid, 85 wt%, at 149 C moderate Phosphoric acid at 149 C corrodes at 0.29 mm/y.7
Hydrofluoric acid, 10 wt%, at 52 C moderate Hydrofluoric acid at 52 C gives 0.41 mm/y of external attack; it can also cause internal attack.8
Weld metal in sulfuric and hydrochloric acid moderate Weld metal corrodes faster than wrought metal in these acids: 0.13 mm/y in 70 percent sulfuric acid, 0.22 mm/y in 10 percent hydrochloric acid.9
Chloride pitting and crevice attack in acidified 6 wt% ferric chloride (ASTM G 48), and Green and Yellow Death tests low Critical pitting temperature above 150 C and critical crevice temperature 55 C for C-276 (Haynes).10
Chloride stress-corrosion cracking, boiling 45 wt% magnesium chloride (ASTM G 36, U-bend samples) none No cracking in 1,008 hours in boiling 45 percent magnesium chloride (Haynes).11
Seawater crevice attack, still and flowing seawater (LaQue test, 180 days) low Maximum crevice depth 0.13 mm in still seawater after 180 days; no attack in flowing seawater.12
Most strongly oxidising acids, such as hot concentrated nitric acid severe ATI says the alloy has too little chromium for hot concentrated nitric acid.13
Wet chlorine service low ATI says it is one of the few materials able to resist wet chlorine.14
Boiling Green Death scrubber solution (7% sulfuric acid, 3% hydrochloric acid, 1% cupric chloride, 1% ferric chloride) severe In boiling Green Death solution ATI 276 corrodes at 26.5 mpy (0.67 mm/a); Type 316 is destroyed.15
Chloride stress-corrosion cracking in boiling 42 percent magnesium chloride, 33 percent lithium chloride and 26 percent sodium chloride none ATI reports resistance for 1000 hours in each boiling chloride solution.16
Seawater and brine (qualitative), and ferric chloride crevice test at 10 percent with 6 percent water low ATI calls the alloy inert to seawater; crevice attack starts at 60 C in its ferric chloride test.17
Intergranular attack tests, boiling ferric sulfate with 50 percent sulfuric acid (ASTM G28 Practice A) and boiling 23 percent sulfuric acid with chlorides (Practice B) not rated ATI reports 200 to 250 mpy in Practice A, against a 480 mpy criterion, and 43 to 48 mpy in Practice B, against a 60 mpy limit.18
Nuclear-waste off-gas and condensate test (3 B-2 solution, boiling, 10 days) low Corrosion under 1.5 mpy and crevice attack under 1 mil in the 3 B-2 test required by the nuclear-waste project.19
Corrosion details
#EnvironmentDetailsTest conditions
1 Nitric acid, 65 wt%, at 66 C to the boil (strongly oxidising) Haynes reagent-grade tests give 0.41 mm/y at 66 C, 2.53 mm/y at 93 C and 22.12 mm/y at boiling for 65 percent nitric acid. Dilute nitric acid is much milder: 0.26 mm/y for 10 percent at the boil. basis reagent-grade acid, laboratory test (Haynes iso-corrosion data)rating basis Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe
2 Chromic acid, 20 wt%, at 66 C (oxidising) Haynes reagent-grade test gives 0.53 mm/y for 20 percent chromic acid at 66 C. basis reagent-grade solution, laboratory testrating basis Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe
3 Hydrochloric acid, 10 wt%, at 38 C (reducing) Haynes gives 0.17 mm/y for 10 percent hydrochloric acid at 38 C, rising to 0.46 mm/y at 66 C and 1.18 mm/y at 79 C. basis reagent-grade acid, laboratory testrating basis Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe
4 Hydrochloric acid, 5 wt%, at the boil (reducing) Haynes gives 3.63 mm/y at boiling for 5 percent hydrochloric acid, 1.25 mm/y at 93 C and 0.75 mm/y at 79 C. basis reagent-grade acid, laboratory testrating basis Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe
5 Sulfuric acid, 10 wt%, at the boil (reducing) Haynes gives 0.18 mm/y at boiling for 10 percent sulfuric acid, and 0.14 mm/y at 93 C. basis reagent-grade acid, laboratory testrating basis Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe
6 Sulfuric acid, 60 wt%, at the boil (reducing) Haynes gives 13.08 mm/y at boiling for 60 percent sulfuric acid, 2.87 mm/y at 121 C and 0.67 mm/y at 93 C. For 50 percent acid at 79 C the rate is 0.26 mm/y. basis reagent-grade acid, laboratory testrating basis Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe
7 Phosphoric acid, 85 wt%, at 149 C Haynes gives 0.29 mm/y for 85 percent phosphoric acid at 149 C, and 1.68 mm/y at the boil. basis reagent-grade acid, laboratory testrating basis Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe
8 Hydrofluoric acid, 10 wt%, at 52 C Haynes gives 0.41 mm/y for 10 percent hydrofluoric acid at 52 C. Its footnote says hydrofluoric acid can also induce internal attack of nickel alloys, and that these values cover external attack only. basis reagent-grade acid, laboratory testrating basis Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe
9 Weld metal in sulfuric and hydrochloric acid Haynes tested all-weld-metal samples from MIG welds. Weld metal gives 0.13 mm/y in 70 percent sulfuric acid at 66 C (wrought 0.05 mm/y) and 0.22 mm/y in 10 percent hydrochloric acid at 38 C (wrought 0.17 mm/y). Haynes says the uneven weld structure gives higher rates than wrought product. basis all-weld-metal samples from multiple gas metal arc passesrating basis Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe
10 Chloride pitting and crevice attack in acidified 6 wt% ferric chloride (ASTM G 48), and Green and Yellow Death tests Haynes gives the critical pitting temperature as 15 C for 316L, 60 C for 254SMO, 100 C for alloy 625 and above 150 C for C-276. The critical crevice temperature is 0 C for 316L, 30 C for 254SMO, 40 C for 625 and 55 C for C-276. In Green Death, pitting is first seen at the boil; in Yellow Death C-276 showed no pitting up to 150 C, with a critical crevice temperature of 60 C. test ASTM G 48 in acidified 6 wt% ferric chloride for 72 hours; Green and Yellow Death tests for 24 hours
11 Chloride stress-corrosion cracking, boiling 45 wt% magnesium chloride (ASTM G 36, U-bend samples) Haynes tested stressed U-bend samples in boiling 45 percent magnesium chloride for 1,008 hours, six weeks. C-276 and 625 showed no cracking; 316L cracked in 2 hours and 254SMO in 24 hours. test ASTM G 36, boiling 45 percent magnesium chloride, stressed U-bend samples, 1008 hours
12 Seawater crevice attack, still and flowing seawater (LaQue test, 180 days) A U.S. Navy study at LaQue Laboratories, reported by Haynes, gives maximum crevice depths of 0.10 mm and 0.13 mm for two C-276 samples in still seawater, and no attack in flowing seawater, after 180 days. 316L reached 2.27 mm in still water. temperature 29 C plus or minus 3 Cexposure 180 days, still and flowing seawater
13 Most strongly oxidising acids, such as hot concentrated nitric acid ATI says the alloy is used in environments from moderately oxidising to strongly reducing. It does not have enough chromium for the most strongly oxidising environments, such as hot, concentrated nitric acid. basis qualitative statement; no concentration or temperature printed
14 Wet chlorine service ATI says the alloy is used in wet chlorine service, where it is one of the few materials able to resist this very aggressive environment. No rate is printed. basis qualitative statement; no rate printed
15 Boiling Green Death scrubber solution (7% sulfuric acid, 3% hydrochloric acid, 1% cupric chloride, 1% ferric chloride) ATI says the alloy is among the most corrosion-resistant materials for coal-burning utility flue-gas scrubbers. In the boiling Green Death simulated scrubber solution it gives 26.5 mpy (0.67 mm/a), where Type 316 is destroyed. basis simulated scrubber solution, boiling (ATI chart)rating basis Haynes bands applied to the ATI rate: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe
16 Chloride stress-corrosion cracking in boiling 42 percent magnesium chloride, 33 percent lithium chloride and 26 percent sodium chloride ATI reports that ATI 276 resisted cracking for 1000 hours in each of the three boiling chloride solutions, where Type 316 failed in 24, 100 and 300 hours. ATI says the high nickel and molybdenum content gives extreme resistance to chloride stress-corrosion cracking. basis U-bend samples; boiling solutions
17 Seawater and brine (qualitative), and ferric chloride crevice test at 10 percent with 6 percent water ATI says the chromium, molybdenum and tungsten content gives such high pitting resistance that the alloy is considered inert to seawater, brine and high-chloride environments. In 10 percent ferric chloride with 6 percent water (ASTM G 48 Practice B), crevice corrosion starts at 60 C (140 F), which ATI says is beyond the stability limit of that solution. basis qualitative seawater statement; ASTM G 48 Practice B onset temperature
18 Intergranular attack tests, boiling ferric sulfate with 50 percent sulfuric acid (ASTM G28 Practice A) and boiling 23 percent sulfuric acid with chlorides (Practice B) For Practice A (24 hours, boiling), ATI gives 250, 200 and 220 mpy for three heats, and states the 480 mpy criterion. For Practice B (24 hours, boiling, with 1.2 percent hydrochloric acid, 1.0 percent ferric chloride and 1.0 percent cupric chloride), ATI gives 43 to 48 mpy and states a limit of 60 mpy. basis acceptance-test rates; the criteria differ from the mm/y bands used for the other ratings
19 Nuclear-waste off-gas and condensate test (3 B-2 solution, boiling, 10 days) ATI says over 1,000 tons of UNS N10276 alloy were supplied for the Savannah River Plant project after the alloy passed this test. Mill annealed and pickled material gave uniform rates of 0.0 to 0.2 mpy, with crevice attack of 0.020 mm in one heat. basis 3 B-2 solution: 0.25% chloride, 0.03% fluoride, 0.003% iodide, 0.08% sulfate, 0.10% nitrate and 0.10% mercury as mercuric chloride, pH 2.2 with sulfuric acid, boiling, 10 days

Risks and side effects

Hazards to people, what happens when a cell overheats, and how the material is handled and stored.

For people

No safety data sheet for this alloy was found in this run, so the hazard flags come from the PubChem nickel record (nickel is about 57 percent of the alloy) and the PubChem record for hydrofluoric acid, which the pickling step uses.

Solid alloy
The PubChem aggregated nickel record flags skin sensitisation (H317, 99.9 percent of reports), suspected cancer (H351, 72.9 percent) and organ damage from prolonged exposure (H372, 99.7 percent).
Pickling acid
ATI recommends pickling in nitric and hydrofluoric acids. The PubChem hydrofluoric acid record lists fatal in contact with skin (H310), fatal if inhaled (H330) and severe skin burns and eye damage (H314).

If a part stays hot too long

These results come from the datasheets, not from field incidents.

Heat exposure
ATI says the alloy will eventually form embrittling high-temperature precipitates, but it gives no time or temperature for them to form.
Code approval
The ASME Section VIII code approves the alloy to 677 C (1250 F), the highest code temperature Haynes prints. Other codes give lower limits, for example 1000 F for ASME Section I.

Handling and heat treatment

Anneal
Anneal at 1121 C (2050 F) and water quench. Re-anneal after hot forming and after cold work that gives 7 percent or more outer-fibre elongation (Haynes).
Pickling
Remove scale with wire brushing or grit blasting, then nitric and hydrofluoric acids, and rinse well (ATI).

Test details
The original wording and numbers from the sources, for readers who want them.

Failure risks

Failure risks
FailureTrigger and consequence
Loss of important properties from raised carbon or siliconmoderate severityFabrication that raises the low carbon and silicon contents, such as oxyacetylene welding or carbon- or silicon-bearing fluxesATI says raising the low carbon and silicon contents may adversely affect important properties of the alloy.
Embrittling precipitates at high temperaturemoderate severityLong exposure at high temperature; ATI prints no time or temperatureATI says the alloy will eventually form embrittling high-temperature precipitates, although it has good high-temperature strength and moderate oxidation resistance.
Loss of stress-corrosion resistance after cold workmoderate severityCold work that gives 7 percent or more outer-fibre elongation without a re-annealHaynes says cold work can affect resistance to stress-corrosion cracking, and that re-annealing restores optimum properties.
Strength gain and ductility loss from cold reductionmoderate severityCold reduction of sheet by 50 percentATI's cold-working table shows yield strength rising from 415 MPa to 1,345 MPa and elongation falling from 50 percent to 7 percent after 50 percent cold reduction.
Attack by hot, concentrated nitric acidhigh severityHot concentrated nitric acid, for example boiling 65 percent acidHaynes gives 22.12 mm/y at the boil in 65 percent nitric acid. ATI says the alloy is not useful in hot, concentrated nitric acid.
Narrow hot-working windowmoderate severityHot working outside the recommended range, from 1232 C (2250 F) to 954 C (1750 F) for forgingHaynes says the alloy is more sensitive to strain and strain rate than austenitic stainless steels, and that its hot-working range is quite narrow.

Handling and storage

  • Solution anneal at 1121 C (2050 F) for 10 to 30 minutes, then water quench. Rapid air cooling is feasible only for structures thinner than 10 mm (Haynes).
  • Solution heat-treat at 1040 to 1150 C (1900 to 2100 F) and cool to black in two minutes or less (ATI).
  • Clean the material before heat treatment and keep it free of grease, oils and other carbon sources (ATI).
  • Stress-relief heat treatments are not effective for this alloy; a full anneal should be used instead (ATI).
  • Descale with stainless wire brushing or grit blasting, then immerse in a mixture of nitric and hydrofluoric acids and rinse thoroughly with water (ATI).
  • Hot forge from a start of 1232 C (2250 F) down to a finish of 954 C (1750 F), with moderate reductions and frequent reheating (Haynes).

Mitigations

  • Re-anneal cold-worked parts after an outer-fibre elongation of 7 percent or more to restore corrosion and stress-corrosion performance (Haynes).
  • For the most severe corrosive service, solution heat-treat the material after welding; ATI says the welded condition is acceptable for most corrosive service (ATI).
  • Use matching filler metal. If the alloy is joined to another nickel alloy or stainless steel in a corrosive environment, use weld metal comparable in corrosion resistance to the more noble alloy (ATI).
  • Avoid oxyacetylene welding and submerged-arc fluxes that contain carbon or silicon, because they cause carbon pick-up (ATI).

Supply and geography

How common the raw materials are and where they come from.

Nickel

Globally, nickel resources have been estimated to contain more than 350 million tons of nickel (USGS)

Top producers (2025)
Indonesia 66.7%, Philippines 6.9%, Russia 5.1%, Canada 3.6%
Recycling
In 2025, nickel recovered from scrap accounted for approximately 60% of apparent consumption (USGS).
Substitutes
USGS: titanium alloys can substitute for nickel or nickel-base alloys in corrosive environments.

Molybdenum

Identified resources in the United States are about 5.4 million tons and, in the rest of the world, about 20 million tons (USGS)

Top producers (2025)
China 37.3%, Chile 16.2%, United States 15.4%, Peru 15%, Mexico 6.5%
Recycling
USGS: molybdenum is recycled as a component of catalysts, ferrous scrap and superalloy scrap, and the recycled amount may be as much as 30% of apparent supply.
Substitutes
USGS: there is little substitution for molybdenum in steels and cast irons; potential substitutes in alloy steels include boron, chromium, niobium and vanadium.

Chromium

World resources are greater than 12 billion tons of shipping-grade chromite (USGS)

Top producers (2025)
South Africa 45.1%, Turkey 17.6%, Kazakhstan 13.7%, India 5.9%
Recycling
In 2025, recycled chromium in reported stainless-steel scrap receipts accounted for 21% of apparent consumption (USGS).
Substitutes
USGS: chromium has no substitute in stainless steel or in superalloys, the major strategic end use.

Tungsten

World tungsten resources are geographically widespread, and China ranked first in resources and reserves (USGS)

Top producers (2025)
China 78.8%, Vietnam 3.5%, Kazakhstan 2.8%, Russia 2.4%
Recycling
USGS: the 2025 amount of secondary tungsten was withheld to avoid disclosing company proprietary data.
Substitutes
USGS: molybdenum can replace some tungsten mill products, and molybdenum steels can replace tungsten steels, although most molybdenum steels still contain tungsten.