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.
Evidence level
2 of 5
Lab-measured
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
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)
| Property | Value | Basis |
|---|---|---|
| Density | 8.89 to 8.9 g/cm³ | 2 sourced values across conditions |
| Yield strength | 283 to 415 MPa | 4 sourced values across conditions |
| Tensile strength | 690 to 792 MPa | 4 sourced values across conditions |
| Young's modulus | 205 GPa | 1 sourced value |
| Thermal conductivity | 7.3 to 19 W/(m·K) | 4 sourced values across conditions |
| Thermal expansion (CTE) | 11.2 to 13.3 ppm/K | 2 sourced values across conditions |
| Melting point | 1,323 to 1,371 °C | 1 sourced value |
| Specific heat | 427 J/(kg·K) | 1 sourced value |
| Electrical resistivity | 0.0000012 to 0.0000013 Ω·m | 2 sourced values across conditions |
| Maximum service temperature | 677 °C | 1 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.
| Ingredient | Share of the weight | What 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.
| Measurement | C-276 (UNS N10276) | IN718 (UNS N07718) | IN625 (UNS N06625) | FeNi36 | Ni-Mo | C-22 | X (UNS N06002) | UNS N07214 | H230 (UNS N06230) | UNS N08800 | Alloy 825 (UNS N08825) | Alloy 600 (UNS N06600, W.Nr. 2.4816) | Alloy 601 | Alloy 617 | X-750 (UNS N07750) | Fe-Ni-Co | Alloy 400 (UNS N04400) | K-500 | Ni | Ni3Al, NiAl | NiBe2 | Ni-alloys | UNS N07090 (W. Nr. 2.4632) | UNS N07001 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Capacity and energy | ||||||||||||||||||||||||
| Charpy V-notch impact energyHaynes Impact Strength table, RT row, J column | 479 J19 | no data | no data | no data | 479 J | 469 J | 140 J | no data | no data | 122 J | no data | 82.4 J | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data |
| Charpy V-notch impact energy | 519 J20 | no data | no data | no data | 479 J | 469 J | 140 J | no data | no data | 122 J | no data | 82.4 J | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data |
| Charpy V-notch impact energy, full thickness | 245 J38 | no data | no data | no data | 479 J | 469 J | 140 J | no data | no data | 122 J | no data | 82.4 J | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data |
| Charpy V-notch impact energy, full thickness | 325 J39 | no data | no data | no data | 479 J | 469 J | 140 J | no data | no data | 122 J | no data | 82.4 J | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data |
| Thermal behavior and safety | ||||||||||||||||||||||||
| melting point | 1323 to 1371 °C2 | 1260 °C | 1290 to 1350 °C | 1427 °C | 1370 to 1418 °C | 1357 to 1399 °C | 1260 to 1355 °C | 1355 to 1400 °C | 1301 to 1371 °C | 1357 to 1385 °C | 1370 to 1400 °C | 1354 to 1413 °C | 1360 to 1411 °C | 1330 to 1380 °C | 1393 to 1427 °C | 1450 °C | 1300 to 1350 °C | 1315 to 1350 °C | 1455 °C | no data | 1195 to 1325 °C | 1425 °C | 1370 °C | 1330 to 1360 °C |
| Thermal conductivity | 10.5 W/m.°C4 | 79 BTU·in/ft²·h·°F | 9.8 W/m°C | 72.85 Btu·in/(hr·ft²·°F) | 11.2 W/m.°C | 10.1 W/(m·K) | 9.2 W/(m·K) | 12 W/m-°C | 8.9 W/(m·°C) | 11.5 W/m°C | 11.1 W/(m·K) | 14.9 W/(m·K) | 11.2 W/(m·K) | 13.4 W/(m·K) | 83 Btu/in./hr/sq ft/°F | 17.5 W/m °K | 22 W/m°C | 17.5 W/m °C | 70.3 W/(m·K) | no data | 48 W/(m·K) | 13 W/(m·K) | 11.47 W/(m·K) | 19.1 W/(m·°C) |
| Thermal conductivity | 18.3 W/m.°C5 | 79 BTU·in/ft²·h·°F | 9.8 W/m°C | 72.85 Btu·in/(hr·ft²·°F) | 11.2 W/m.°C | 10.1 W/(m·K) | 9.2 W/(m·K) | 12 W/m-°C | 8.9 W/(m·°C) | 11.5 W/m°C | 11.1 W/(m·K) | 14.9 W/(m·K) | 11.2 W/(m·K) | 13.4 W/(m·K) | 83 Btu/in./hr/sq ft/°F | 17.5 W/m °K | 22 W/m°C | 17.5 W/m °C | 70.3 W/(m·K) | no data | 48 W/(m·K) | 13 W/(m·K) | 11.47 W/(m·K) | 19.1 W/(m·°C) |
| specific heat | 427 J/kg.°C8 | 435 J/kg °C | 410 J/(kg·K) | 515 J/(kg·K) | 373 J/kg.°C | 410 J/(kg·K) | 486 J/(kg·K) | 452 J/kg-°C | 397 J/kg·°C | 460 J/kg·°C | 440 J/(kg·K) | 444 J/kg °C | 448 J/(kg·K) | 419 J/(kg·K) | 0.103 Btu/lb/°F | 500 J/(kg. K) | 427 J/kg°C | 419 J/kg °C | 456 J/(kg·K) | no data | no data | 500 J/(kg·K) | 446 J/(kg·K) | no data |
| Thermal conductivity | 7.3 W/m•K26 | 79 BTU·in/ft²·h·°F | 9.8 W/m°C | 72.85 Btu·in/(hr·ft²·°F) | 11.2 W/m.°C | 10.1 W/(m·K) | 9.2 W/(m·K) | 12 W/m-°C | 8.9 W/(m·°C) | 11.5 W/m°C | 11.1 W/(m·K) | 14.9 W/(m·K) | 11.2 W/(m·K) | 13.4 W/(m·K) | 83 Btu/in./hr/sq ft/°F | 17.5 W/m °K | 22 W/m°C | 17.5 W/m °C | 70.3 W/(m·K) | no data | 48 W/(m·K) | 13 W/(m·K) | 11.47 W/(m·K) | 19.1 W/(m·°C) |
| Thermal conductivity | 19 W/m•K27 | 79 BTU·in/ft²·h·°F | 9.8 W/m°C | 72.85 Btu·in/(hr·ft²·°F) | 11.2 W/m.°C | 10.1 W/(m·K) | 9.2 W/(m·K) | 12 W/m-°C | 8.9 W/(m·°C) | 11.5 W/m°C | 11.1 W/(m·K) | 14.9 W/(m·K) | 11.2 W/(m·K) | 13.4 W/(m·K) | 83 Btu/in./hr/sq ft/°F | 17.5 W/m °K | 22 W/m°C | 17.5 W/m °C | 70.3 W/(m·K) | no data | 48 W/(m·K) | 13 W/(m·K) | 11.47 W/(m·K) | 19.1 W/(m·°C) |
| Physical and electrical | ||||||||||||||||||||||||
| Density | 8.89 g/cm³1 | 0.297 lb/in3 | 8.44 g/cm³ | 8.05 g/cm³ | 9.22 g/cm³ | 8.69 g/cm³ | 8.22 g/cm³ | 8.05 g/cm³ | 8.97 g/cm³ | 7.94 g/cm³ | 8.14 g/cm³ | 0.306 lb/in3 | 8.11 Mg/m3 | 8.36 g/cm³ | 8.28 g/cm³ | 8.36 g/cm³ | 8.8 g/cm³ | 8.45 g/cm³ | 8.89 g/cm³ | 7.5 g/cm³ | 8.27 g/cm³ | 8.2 g/cm³ | 8.18 g/cm³ | 8.19 g/cm³ |
| electrical resistivity | 1.23 μohm.m3 | 725 ohm circ mil/ft | 129 µΩ-cm | 84 µΩ·cm | 1.37 μohm.m | 1.14 µΩ·m | 114.8 µohm-cm | 135.9 µohm-cm | 125 µohm-m | 0.989 µΩ·m | 112 µΩ·cm | 1.03 µΩ·m | 1.18 µΩ·m | 1.22×10^-4 Ω·cm | 731 ohm circ mil/ft | 49 μΩcm | 0.511 µΩ·m | 0.615 µΩ·m | 0.096 µΩ·m | no data | < 28.7 µΩ·cm | 45 µΩ·cm | 1.18 µΩ·m | 1.24 µΩ·m |
| Rockwell B hardness, tungsten indenter (HRBW)Haynes Hardness table, Sheet row | 88 HRBW | no data | no data | no data | no data | no data | 87 HRBW | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data |
| Rockwell B hardness, tungsten indenter (HRBW)Haynes Hardness table, Bar row | 86 HRBW | no data | no data | no data | no data | no data | 87 HRBW | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data |
| Density | 8.9 g/cm³24 | 0.297 lb/in3 | 8.44 g/cm³ | 8.05 g/cm³ | 9.22 g/cm³ | 8.69 g/cm³ | 8.22 g/cm³ | 8.05 g/cm³ | 8.97 g/cm³ | 7.94 g/cm³ | 8.14 g/cm³ | 0.306 lb/in3 | 8.11 Mg/m3 | 8.36 g/cm³ | 8.28 g/cm³ | 8.36 g/cm³ | 8.8 g/cm³ | 8.45 g/cm³ | 8.89 g/cm³ | 7.5 g/cm³ | 8.27 g/cm³ | 8.2 g/cm³ | 8.18 g/cm³ | 8.19 g/cm³ |
| electrical resistivity | 130 microhm-cm25 | 725 ohm circ mil/ft | 129 µΩ-cm | 84 µΩ·cm | 1.37 μohm.m | 1.14 µΩ·m | 114.8 µohm-cm | 135.9 µohm-cm | 125 µohm-m | 0.989 µΩ·m | 112 µΩ·cm | 1.03 µΩ·m | 1.18 µΩ·m | 1.22×10^-4 Ω·cm | 731 ohm circ mil/ft | 49 μΩcm | 0.511 µΩ·m | 0.615 µΩ·m | 0.096 µΩ·m | no data | < 28.7 µΩ·cm | 45 µΩ·cm | 1.18 µΩ·m | 1.24 µΩ·m |
| Temperature behavior | ||||||||||||||||||||||||
| Critical pitting temperature in acidified 6% ferric chloride | > 150 °C22 | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data |
| Critical crevice temperature in acidified 6% ferric chloride | 55 °C23 | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data | no data |
| Other measurements | ||||||||||||||||||||||||
| Thermal expansion (CTE) | 11.2 μm/m.°C6 | 8.91 ppm/°F | 12.8 ppm/°C | 1.3 ppm/K | 10.6 μm/m.°C | 12.4 ppm/K | 13.9 µm/(m·K) | 14.6 µm/m-°C | 11.8 ppm/K | 14.4 µm/m/°C | 13.9 ppm/K | 10.4 ppm/K | 13.75 µm/m/°C | 11.6 µm/(m·K) | 7 10-6 in./in./°F | 5.86 10-6/°C | 14.2 µm/m°C | 13.7 10-6/°C | 13.3 ppm/K | no data | 14.5 ppm/K | 8 ppm/K | 12.7 µm/(m·K) | 14.3 µm/m·°C |
| Thermal expansion (CTE) | 13.3 μm/m.°C7 | 8.91 ppm/°F | 12.8 ppm/°C | 1.3 ppm/K | 10.6 μm/m.°C | 12.4 ppm/K | 13.9 µm/(m·K) | 14.6 µm/m-°C | 11.8 ppm/K | 14.4 µm/m/°C | 13.9 ppm/K | 10.4 ppm/K | 13.75 µm/m/°C | 11.6 µm/(m·K) | 7 10-6 in./in./°F | 5.86 10-6/°C | 14.2 µm/m°C | 13.7 10-6/°C | 13.3 ppm/K | no data | 14.5 ppm/K | 8 ppm/K | 12.7 µm/(m·K) | 14.3 µm/m·°C |
| elastic modulus | 205 GPa9 | 29 ksi x 10^3 | 207.5 GPa | 140 GPa | 216 GPa | 206 GPa | 205 GPa | 218 GPa | 209 GPa | 196.5 GPa | 196 GPa | 214 GPa | 206.5 GPa | 211 GPa | 31 10^3 ksi | 138 kN/mm2 | 26 10^3 ksi | 179 GPa | 205 GPa | 200 GPa | 195 to 210 GPa | no data | 204 GPa | 211 GPa |
| elastic modulus | 178 GPa10 | 29 ksi x 10^3 | 207.5 GPa | 140 GPa | 216 GPa | 206 GPa | 205 GPa | 218 GPa | 209 GPa | 196.5 GPa | 196 GPa | 214 GPa | 206.5 GPa | 211 GPa | 31 10^3 ksi | 138 kN/mm2 | 26 10^3 ksi | 179 GPa | 205 GPa | 200 GPa | 195 to 210 GPa | no data | 204 GPa | 211 GPa |
| poissons ratio | 0.31 -11 | 0.294 - | 0.278 - | no data | no data | no data | 0.32 - | no data | 0.31 - | 0.339 - | no data | 0.324 - | 0.272 - | no data | 0.29 - | no data | 0.32 - | no data | no data | no data | 0.3 - | no data | no data | no data |
| yield strength | 356 MPa12 | 171 ksi | 60 to 95 ksi | 40 ksi | 421 MPa | > 310 MPa | 340 MPa | 577 MPa | 417 MPa | 250 MPa | 338 MPa | 170 to 345 MPa | 292 MPa | 340 MPa | > 105 ksi | > 200 N/mm2 | 25 to 50 ksi | 276 to 414 MPa | 105 to 210 MPa | no data | 280 to 480 MPa | 280 MPa | 752 MPa | 586 MPa |
| ultimate tensile strength | 792 MPa13 | 201 ksi | 120 to 150 ksi | 65 ksi | 862 MPa | 690 to 950 MPa | 760 MPa | 975 MPa | 837 MPa | 590 MPa | 662 MPa | 550 to 690 MPa | 675 MPa | 710 MPa | > 165 ksi | 450 to 585 N/mm2 | 75 to 90 ksi | 621 to 758 MPa | 380 to 520 MPa | 2300 MPa | 660 to 900 MPa | 500 MPa | 1175 MPa | 1027 MPa |
| elongation | 61 %14 | 26 % | 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 strength | 365 MPa15 | 171 ksi | 60 to 95 ksi | 40 ksi | 421 MPa | > 310 MPa | 340 MPa | 577 MPa | 417 MPa | 250 MPa | 338 MPa | 170 to 345 MPa | 292 MPa | 340 MPa | > 105 ksi | > 200 N/mm2 | 25 to 50 ksi | 276 to 414 MPa | 105 to 210 MPa | no data | 280 to 480 MPa | 280 MPa | 752 MPa | 586 MPa |
| ultimate tensile strength | 785 MPa16 | 201 ksi | 120 to 150 ksi | 65 ksi | 862 MPa | 690 to 950 MPa | 760 MPa | 975 MPa | 837 MPa | 590 MPa | 662 MPa | 550 to 690 MPa | 675 MPa | 710 MPa | > 165 ksi | 450 to 585 N/mm2 | 75 to 90 ksi | 621 to 758 MPa | 380 to 520 MPa | 2300 MPa | 660 to 900 MPa | 500 MPa | 1175 MPa | 1027 MPa |
| yield strength | 225 MPa17 | 171 ksi | 60 to 95 ksi | 40 ksi | 421 MPa | > 310 MPa | 340 MPa | 577 MPa | 417 MPa | 250 MPa | 338 MPa | 170 to 345 MPa | 292 MPa | 340 MPa | > 105 ksi | > 200 N/mm2 | 25 to 50 ksi | 276 to 414 MPa | 105 to 210 MPa | no data | 280 to 480 MPa | 280 MPa | 752 MPa | 586 MPa |
| ultimate tensile strength | 650 MPa18 | 201 ksi | 120 to 150 ksi | 65 ksi | 862 MPa | 690 to 950 MPa | 760 MPa | 975 MPa | 837 MPa | 590 MPa | 662 MPa | 550 to 690 MPa | 675 MPa | 710 MPa | > 165 ksi | 450 to 585 N/mm2 | 75 to 90 ksi | 621 to 758 MPa | 380 to 520 MPa | 2300 MPa | 660 to 900 MPa | 500 MPa | 1175 MPa | 1027 MPa |
| Maximum service temperature | 677 °C21 | 1300 °F | 982 °C | no data | no data | no data | no data | 1260 °C | no data | no data | no data | no data | 1000 °C | no data | 1200 °F | no data | no data | 650 °C | no data | 1373 K | no data | no data | no data | 650 °C |
| yield strength | > 283 MPa28 | 171 ksi | 60 to 95 ksi | 40 ksi | 421 MPa | > 310 MPa | 340 MPa | 577 MPa | 417 MPa | 250 MPa | 338 MPa | 170 to 345 MPa | 292 MPa | 340 MPa | > 105 ksi | > 200 N/mm2 | 25 to 50 ksi | 276 to 414 MPa | 105 to 210 MPa | no data | 280 to 480 MPa | 280 MPa | 752 MPa | 586 MPa |
| ultimate tensile strength | > 690 MPa29 | 201 ksi | 120 to 150 ksi | 65 ksi | 862 MPa | 690 to 950 MPa | 760 MPa | 975 MPa | 837 MPa | 590 MPa | 662 MPa | 550 to 690 MPa | 675 MPa | 710 MPa | > 165 ksi | 450 to 585 N/mm2 | 75 to 90 ksi | 621 to 758 MPa | 380 to 520 MPa | 2300 MPa | 660 to 900 MPa | 500 MPa | 1175 MPa | 1027 MPa |
| elongation | > 40 %30 | 26 % | 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 strength | 565 MPa31 | 171 ksi | 60 to 95 ksi | 40 ksi | 421 MPa | > 310 MPa | 340 MPa | 577 MPa | 417 MPa | 250 MPa | 338 MPa | 170 to 345 MPa | 292 MPa | 340 MPa | > 105 ksi | > 200 N/mm2 | 25 to 50 ksi | 276 to 414 MPa | 105 to 210 MPa | no data | 280 to 480 MPa | 280 MPa | 752 MPa | 586 MPa |
| ultimate tensile strength | 965 MPa32 | 201 ksi | 120 to 150 ksi | 65 ksi | 862 MPa | 690 to 950 MPa | 760 MPa | 975 MPa | 837 MPa | 590 MPa | 662 MPa | 550 to 690 MPa | 675 MPa | 710 MPa | > 165 ksi | 450 to 585 N/mm2 | 75 to 90 ksi | 621 to 758 MPa | 380 to 520 MPa | 2300 MPa | 660 to 900 MPa | 500 MPa | 1175 MPa | 1027 MPa |
| elongation | 45 %33 | 26 % | 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 strength | 415 MPa34 | 171 ksi | 60 to 95 ksi | 40 ksi | 421 MPa | > 310 MPa | 340 MPa | 577 MPa | 417 MPa | 250 MPa | 338 MPa | 170 to 345 MPa | 292 MPa | 340 MPa | > 105 ksi | > 200 N/mm2 | 25 to 50 ksi | 276 to 414 MPa | 105 to 210 MPa | no data | 280 to 480 MPa | 280 MPa | 752 MPa | 586 MPa |
| ultimate tensile strength | 790 MPa35 | 201 ksi | 120 to 150 ksi | 65 ksi | 862 MPa | 690 to 950 MPa | 760 MPa | 975 MPa | 837 MPa | 590 MPa | 662 MPa | 550 to 690 MPa | 675 MPa | 710 MPa | > 165 ksi | 450 to 585 N/mm2 | 75 to 90 ksi | 621 to 758 MPa | 380 to 520 MPa | 2300 MPa | 660 to 900 MPa | 500 MPa | 1175 MPa | 1027 MPa |
| yield strength | 270 MPa36 | 171 ksi | 60 to 95 ksi | 40 ksi | 421 MPa | > 310 MPa | 340 MPa | 577 MPa | 417 MPa | 250 MPa | 338 MPa | 170 to 345 MPa | 292 MPa | 340 MPa | > 105 ksi | > 200 N/mm2 | 25 to 50 ksi | 276 to 414 MPa | 105 to 210 MPa | no data | 280 to 480 MPa | 280 MPa | 752 MPa | 586 MPa |
| ultimate tensile strength | 640 MPa37 | 201 ksi | 120 to 150 ksi | 65 ksi | 862 MPa | 690 to 950 MPa | 760 MPa | 975 MPa | 837 MPa | 590 MPa | 662 MPa | 550 to 690 MPa | 675 MPa | 710 MPa | > 165 ksi | 450 to 585 N/mm2 | 75 to 90 ksi | 621 to 758 MPa | 380 to 520 MPa | 2300 MPa | 660 to 900 MPa | 500 MPa | 1175 MPa | 1027 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.
| System | Codes |
|---|---|
| UNS | N10276, W10276 (welding filler metal form, printed beside N10276) |
| EN | 2.4819 |
| EN name | NiMo16Cr15W |
| DIN | 17744 |
| ASTM | B 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) |
| ASME | SB 574 (billet, rod and bar), SB 575 (sheet, plate and strip), SB 619 (welded pipe and tube), SB 622 (seamless pipe and tube) |
| NACE | MR0175 (sour-service listing) |
| Trade name | HASTELLOY® C-276, ATI 276 |
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Density | Haynes Physical Properties table, Density row at room temperature, metric column | temperature room temperaturebasis metric column of the physical properties table; 0.321 lb/in3 is printed alongside | — |
| 2 | melting point | Haynes Physical Properties table, Melting Range row, metric column | basis melting range, metric column; 2415 to 2500 F is printed alongside | — |
| 3 | electrical resistivity | Haynes Physical Properties table, Electrical Resistivity, RT row, metric column | temperature room temperaturebasis 48.4 μohm.in is printed alongside | — |
| 4 | Thermal conductivity | Haynes Physical Properties table, Thermal Conductivity, 50 °C row | temperature 50 °Cbasis metric column; the British column lists other temperatures | — |
| 5 | Thermal conductivity | Haynes Physical Properties table, Thermal Conductivity, 500 °C row | temperature 500 °Cbasis metric column | — |
| 6 | Thermal expansion (CTE) | Haynes Physical Properties table, Mean Coefficient of Thermal Expansion, 24-100 °C row, metric column | temperature range 24 to 100 °Cbasis mean coefficient of thermal expansion from 24 °C | — |
| 7 | Thermal expansion (CTE) | Haynes Physical Properties table, Mean Coefficient of Thermal Expansion, 24-500 °C row, metric column | temperature range 24 to 500 °Cbasis mean coefficient of thermal expansion from 24 °C | — |
| 8 | specific heat | Haynes Physical Properties table, Specific Heat, RT row | temperature room temperaturebasis metric column; 0.102 Btu/lb.°F is printed alongside | — |
| 9 | elastic modulus | Haynes Physical Properties table, Dynamic Modulus of Elasticity, RT row, metric column | temperature room temperaturebasis printed as dynamic modulus of elasticity | — |
| 10 | elastic modulus | Haynes Physical Properties table, Dynamic Modulus of Elasticity, 500 °C row, metric column | temperature 500 °Cbasis printed as dynamic modulus of elasticity | — |
| 11 | poissons ratio | Haynes Physical Properties table, Poisson's Ratio, RT row | temperature room temperature | — |
| 12 | yield strength | Haynes Tensile Strength and Elongation table, Sheet row at RT, MPa column; 51.6 ksi is printed alongside | condition 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 | — |
| 13 | ultimate tensile strength | Haynes Tensile Strength and Elongation table, Sheet row at RT, MPa column; 114.9 ksi is printed alongside | condition mill annealed, the solution anneal (supply condition)product sheet, 2 mm (0.078 in) thicktemperature room temperature | — |
| 14 | elongation | Haynes Tensile Strength and Elongation table, Sheet row at RT | condition mill annealed, the solution anneal (supply condition)product sheet, 2 mm (0.078 in) thicktemperature room temperature | — |
| 15 | yield strength | Haynes Tensile Strength and Elongation table, Plate row at RT, MPa column; 52.9 ksi is printed alongside | condition mill annealed, the solution anneal (supply condition)product plate, 25.4 mm (1 in) thicktemperature room temperatureoffset 0.2 percent | — |
| 16 | ultimate tensile strength | Haynes Tensile Strength and Elongation table, Plate row at RT, MPa column; 113.9 ksi is printed alongside | condition mill annealed, the solution anneal (supply condition)product plate, 25.4 mm (1 in) thicktemperature room temperature | — |
| 17 | yield strength | Haynes Tensile Strength and Elongation table, Sheet row at 800 F (427 C), MPa column; 32.7 ksi is printed alongside | condition mill annealed, the solution anneal (supply condition)product sheet, 2 mm (0.078 in) thicktemperature 427 °C (800 °F)offset 0.2 percent | — |
| 18 | ultimate tensile strength | Haynes Tensile Strength and Elongation table, Sheet row at 800 F (427 C), MPa column; 94.3 ksi is printed alongside | condition mill annealed, the solution anneal (supply condition)product sheet, 2 mm (0.078 in) thicktemperature 427 °C (800 °F) | — |
| 19 | Charpy V-notch impact energy | — | temperature room temperaturespecimen Charpy V-notch, mill annealed platebasis 353 ft-lbf is printed alongside | — |
| 20 | Charpy V-notch impact energy | Haynes Impact Strength table, -320 F row, J column | temperature -196 °C (-320 °F)specimen Charpy V-notch, mill annealed platebasis 383 ft-lbf is printed alongside | — |
| 21 | Maximum service temperature | Haynes Specifications and Codes page, Codes table, ASME Section VIII row | basis 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 footnotes | A code approval temperature, not a test result. The brochure gives lower code limits for other codes, for example 1000 F for ASME Section I. |
| 22 | Critical pitting temperature in acidified 6% ferric chloride | Haynes Resistance to Pitting and Crevice Corrosion table, C-276 row | test ASTM G 48 in acidified 6 wt% ferric chloride; lowest temperature for attack within 72 hoursbasis printed as >150 C (>302 F) | — |
| 23 | Critical crevice temperature in acidified 6% ferric chloride | Haynes Resistance to Pitting and Crevice Corrosion table, C-276 row | test ASTM G 48 in acidified 6 wt% ferric chloride; within 72 hoursbasis printed as 131 F | — |
| 24 | Density | ATI TDS, Physical Properties, Density; 0.321 lb/in3 is printed alongside | basis typical value; temperature not stated | ATI prints 8.90 and Haynes prints 8.89. Both are kept with their own sources. |
| 25 | electrical resistivity | ATI TDS, Physical Properties, Electrical Resistivity | temperature 70 F (21 C)basis typical value | Haynes prints 1.23 μohm.m at room temperature in a different unit. Both values are kept as printed. |
| 26 | Thermal conductivity | ATI TDS, Thermal Conductivity table, -270 F row, W/m K column | temperature -168 °C (-270 °F)basis typical value; no test condition printed in the table | — |
| 27 | Thermal conductivity | ATI TDS, Thermal Conductivity table, 1000 F row, W/m K column | temperature 538 °C (1000 °F)basis typical value; no test condition printed in the table | — |
| 28 | yield strength | ATI TDS, Minimum Properties (ASTM B 575) table; 41,000 psi (283 MPa) is printed | specification 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 percent | Specification minimum, not a typical value. |
| 29 | ultimate tensile strength | ATI TDS, Minimum Properties (ASTM B 575) table; 100,000 psi (690 MPa) is printed | specification ASTM B 575 minimum for plate, sheet and strip, as printed by ATIcondition solution-annealed (ATI: all forms are furnished solution-annealed)temperature room temperature | Specification minimum, not a typical value. |
| 30 | elongation | ATI TDS, Minimum Properties (ASTM B 575) table; elongation in 2 inch, minimum 40 percent | specification ASTM B 575 minimum for plate, sheet and strip, as printed by ATIcondition solution-annealed (ATI: all forms are furnished solution-annealed)gauge 2 inch | Specification minimum, not a typical value. |
| 31 | yield strength | ATI TDS, short-time tensile table, -320 F row, 0.2 percent yield, MPa | temperature -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 | — |
| 32 | ultimate tensile strength | ATI TDS, short-time tensile table, -320 F row, tensile strength, MPa | temperature -196 °C (-320 °F)condition annealed at 2100 F (1150 C) and water quenched (ATI test material)basis typical short-time tensile value | — |
| 33 | elongation | ATI TDS, short-time tensile table, -320 F row, elongation | temperature -196 °C (-320 °F)condition annealed at 2100 F (1150 C) and water quenched (ATI test material)basis typical short-time tensile value | — |
| 34 | yield strength | ATI TDS, short-time tensile table, 70 F row, 0.2 percent yield, MPa | temperature 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 | — |
| 35 | ultimate tensile strength | ATI TDS, short-time tensile table, 70 F row, tensile strength, MPa | temperature 21 °C (70 °F)condition annealed at 2100 F (1150 C) and water quenched (ATI test material)basis typical short-time tensile value | — |
| 36 | yield strength | ATI TDS, short-time tensile table, 1000 F row, 0.2 percent yield, MPa | temperature 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 | — |
| 37 | ultimate tensile strength | ATI TDS, short-time tensile table, 1000 F row, tensile strength, MPa | temperature 538 °C (1000 °F)condition annealed at 2100 F (1150 C) and water quenched (ATI test material)basis typical short-time tensile value | — |
| 38 | Charpy V-notch impact energy, full thickness | ATI TDS, Impact Resistant table, -320 F row, Joules column | temperature -196 °C (-320 °F)specimen full thickness 10 mm sample from annealed platebasis 180 ft-lbs is printed alongside | — |
| 39 | Charpy V-notch impact energy, full thickness | ATI TDS, Impact Resistant table, 70 F row, Joules column | temperature 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.
| Environment | Concern | What 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 |
| # | Environment | Details | Test 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 | Trigger and consequence |
|---|---|
| Loss of important properties from raised carbon or siliconmoderate severity | Fabrication 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 severity | Long 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 severity | Cold 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 severity | Cold 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 severity | Hot 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 severity | Hot 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.
Documents
Datasheets, safety data sheets, papers and standards you can open.
| Document | Type | Year |
|---|---|---|
| HASTELLOY C-276 alloy brochure H-2002H, Haynes International (2023) | datasheet | 2023 |
| ATI 276 Technical Data Sheet, version 1 (2014) | datasheet | 2014 |
| USGS Mineral Commodity Summaries 2026: Nickel | report | 2026 |
| USGS Mineral Commodity Summaries 2026: Molybdenum | report | 2026 |
| USGS Mineral Commodity Summaries 2026: Chromium | report | 2026 |
| USGS Mineral Commodity Summaries 2026: Tungsten | report | 2026 |
| PubChem: Nickel (CID 935), GHS classification | database | |
| PubChem: Hydrofluoric Acid (CID 14917), GHS classification | database |
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
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spore: profile
id: hastelloy-c276
spore_version: 0.2
family: nickel-alloys
name: Hastelloy C-276
abbreviation: C-276 (UNS N10276)
role: corrosion-resistant nickel-molybdenum-chromium alloy
category: metals
type: nickel-superalloys
summary: |
Hastelloy C-276 (UNS N10276, W.Nr. 2.4819) is a nickel-molybdenum-chromium-tungsten alloy. Haynes says it was the first wrought nickel-chromium-molybdenum material to alleviate concerns over welding. Haynes and ATI both report resistance to oxidising and reducing acids, to chloride pitting and crevice attack, and to chloride stress-corrosion cracking. The sources name chemical plants, flue-gas desulfurization ducting and nuclear-waste processing; none names a space use.
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
identity:
formula: '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.'
source: haynes-c276
where: Nominal Composition table, page 1 of Haynes brochure H-2002H (maximum limits in the same table); ATI 276 TDS, Typical Composition table, page 2
designations:
- system: UNS
code: N10276
source: haynes-c276
where: Principal Features, first paragraph
- system: UNS
code: W10276
note: welding filler metal form, printed beside N10276
source: haynes-c276
where: Specifications and Codes, alloy heading (N10276, W10276)
- system: EN
code: '2.4819'
source: haynes-c276
where: Specifications and Codes, DIN 17744 No. 2.4819 NiMo16Cr15W
- system: EN name
code: NiMo16Cr15W
source: haynes-c276
where: Specifications and Codes, DIN 17744 row
- system: DIN
code: '17744'
note: standard that lists No. 2.4819 as NiMo16Cr15W
source: haynes-c276
where: Specifications and Codes, DIN row
- system: ASTM
code: B 574
note: billet, rod and bar
source: haynes-c276
where: Specifications and Codes, Billet, Rod and Bar row (SB 574/B 574)
- system: ASTM
code: B 575
note: sheet, plate and strip
source: haynes-c276
where: Specifications and Codes, Sheet, Plate and Strip row (SB 575/B 575)
- system: ASTM
code: B 619
note: welded pipe and tube
source: haynes-c276
where: Specifications and Codes, Welded Pipe and Tube row (SB 619/B 619)
- system: ASTM
code: B 622
note: seamless pipe and tube
source: haynes-c276
where: Specifications and Codes, Seamless Pipe and Tube row (SB 622/B 622)
- system: ASTM
code: B 626
note: welded tube
source: haynes-c276
where: Specifications and Codes, Welded Pipe and Tube row (SB 626/B 626)
- system: ASTM
code: B 366
note: fittings
source: haynes-c276
where: Specifications and Codes, Fittings row (SB 366/B 366)
- system: ASTM
code: B 564
note: forgings
source: haynes-c276
where: Specifications and Codes, Forgings row (SB 564/B 564)
- system: ASTM
code: B 983
note: seamless pipe and tube
source: haynes-c276
where: Specifications and Codes, Seamless Pipe and Tube row (B 983)
- system: ASME
code: SB 574
note: billet, rod and bar
source: haynes-c276
where: Specifications and Codes, Billet, Rod and Bar row
- system: ASME
code: SB 575
note: sheet, plate and strip
source: haynes-c276
where: Specifications and Codes, Sheet, Plate and Strip row
- system: ASME
code: SB 619
note: welded pipe and tube
source: haynes-c276
where: Specifications and Codes, Welded Pipe and Tube row
- system: ASME
code: SB 622
note: seamless pipe and tube
source: haynes-c276
where: Specifications and Codes, Seamless Pipe and Tube row
- system: NACE
code: MR0175
note: sour-service listing
source: haynes-c276
where: Specifications and Codes, NACE MR0175 entry
- system: Trade name
code: HASTELLOY® C-276
source: haynes-c276
where: Title, page 1
- system: Trade name
code: ATI 276
source: ati-tds
where: Title, page 1
tags:
environments: []
stresses: []
applications:
- structures
properties:
- benchmark: density
value: 8.89
unit: g/cm3
scope: material
conditions:
temperature: room temperature
basis: metric column of the physical properties table; 0.321 lb/in3 is printed alongside
method: Haynes Physical Properties table, Density row at room temperature, metric column
status: ground
source: haynes-c276
where: Physical Properties table, Density row (RT)
- benchmark: melting_point
value: 1323
value_high: 1371
bound: range
unit: °C
scope: material
conditions:
basis: melting range, metric column; 2415 to 2500 F is printed alongside
method: Haynes Physical Properties table, Melting Range row, metric column
status: ground
source: haynes-c276
where: Physical Properties table, Melting Range row
- benchmark: electrical_resistivity
value: 1.23
unit: μohm.m
scope: material
conditions:
temperature: room temperature
basis: 48.4 μohm.in is printed alongside
method: Haynes Physical Properties table, Electrical Resistivity, RT row, metric column
status: ground
source: haynes-c276
where: Physical Properties table, Electrical Resistivity, RT row
- benchmark: thermal_conductivity
value: 10.5
unit: W/m.°C
scope: material
conditions:
temperature: 50 °C
basis: metric column; the British column lists other temperatures
method: Haynes Physical Properties table, Thermal Conductivity, 50 °C row
status: ground
source: haynes-c276
where: Physical Properties table, Thermal Conductivity, 50 °C row
- benchmark: thermal_conductivity
value: 18.3
unit: W/m.°C
scope: material
conditions:
temperature: 500 °C
basis: metric column
method: Haynes Physical Properties table, Thermal Conductivity, 500 °C row
status: ground
source: haynes-c276
where: Physical Properties table, Thermal Conductivity, 500 °C row
- benchmark: cte
value: 11.2
unit: μm/m.°C
scope: material
conditions:
temperature_range: 24 to 100 °C
basis: mean coefficient of thermal expansion from 24 °C
method: Haynes Physical Properties table, Mean Coefficient of Thermal Expansion, 24-100 °C row, metric column
status: ground
source: haynes-c276
where: Physical Properties table, Mean Coefficient of Thermal Expansion, 24-100 °C row
- benchmark: cte
value: 13.3
unit: μm/m.°C
scope: material
conditions:
temperature_range: 24 to 500 °C
basis: mean coefficient of thermal expansion from 24 °C
method: Haynes Physical Properties table, Mean Coefficient of Thermal Expansion, 24-500 °C row, metric column
status: ground
source: haynes-c276
where: Physical Properties table, Mean Coefficient of Thermal Expansion, 24-500 °C row
- benchmark: specific_heat
value: 427
unit: J/kg.°C
scope: material
conditions:
temperature: room temperature
basis: metric column; 0.102 Btu/lb.°F is printed alongside
method: Haynes Physical Properties table, Specific Heat, RT row
status: ground
source: haynes-c276
where: Physical Properties table, Specific Heat, RT row
- benchmark: elastic_modulus
value: 205
unit: GPa
scope: material
conditions:
temperature: room temperature
basis: printed as dynamic modulus of elasticity
method: Haynes Physical Properties table, Dynamic Modulus of Elasticity, RT row, metric column
status: ground
source: haynes-c276
where: Physical Properties table, Dynamic Modulus of Elasticity, RT row
- benchmark: elastic_modulus
value: 178
unit: GPa
scope: material
conditions:
temperature: 500 °C
basis: printed as dynamic modulus of elasticity
method: Haynes Physical Properties table, Dynamic Modulus of Elasticity, 500 °C row, metric column
status: ground
source: haynes-c276
where: Physical Properties table, Dynamic Modulus of Elasticity, 500 °C row
- benchmark: poissons_ratio
value: 0.31
unit: '-'
scope: material
conditions:
temperature: room temperature
method: Haynes Physical Properties table, Poisson's Ratio, RT row
status: ground
source: haynes-c276
where: Physical Properties table, Poisson's Ratio row
- benchmark: yield_strength
value: 356
unit: MPa
scope: material
conditions:
condition: mill annealed, which Haynes describes as the solution anneal (supply condition; the table does not restate it)
product: sheet, 2 mm (0.078 in) thick
temperature: room temperature
offset: 0.2 percent
method: Haynes Tensile Strength and Elongation table, Sheet row at RT, MPa column; 51.6 ksi is printed alongside
status: ground
source: haynes-c276
where: Tensile Strength and Elongation table, Sheet, RT row
- benchmark: ultimate_tensile_strength
value: 792
unit: MPa
scope: material
conditions:
condition: mill annealed, the solution anneal (supply condition)
product: sheet, 2 mm (0.078 in) thick
temperature: room temperature
method: Haynes Tensile Strength and Elongation table, Sheet row at RT, MPa column; 114.9 ksi is printed alongside
status: ground
source: haynes-c276
where: Tensile Strength and Elongation table, Sheet, RT row
- benchmark: elongation
value: 61
unit: '%'
scope: material
conditions:
condition: mill annealed, the solution anneal (supply condition)
product: sheet, 2 mm (0.078 in) thick
temperature: room temperature
method: Haynes Tensile Strength and Elongation table, Sheet row at RT
status: ground
source: haynes-c276
where: Tensile Strength and Elongation table, Sheet, RT row
- benchmark: yield_strength
value: 365
unit: MPa
scope: material
conditions:
condition: mill annealed, the solution anneal (supply condition)
product: plate, 25.4 mm (1 in) thick
temperature: room temperature
offset: 0.2 percent
method: Haynes Tensile Strength and Elongation table, Plate row at RT, MPa column; 52.9 ksi is printed alongside
status: ground
source: haynes-c276
where: Tensile Strength and Elongation table, Plate, RT row
- benchmark: ultimate_tensile_strength
value: 785
unit: MPa
scope: material
conditions:
condition: mill annealed, the solution anneal (supply condition)
product: plate, 25.4 mm (1 in) thick
temperature: room temperature
method: Haynes Tensile Strength and Elongation table, Plate row at RT, MPa column; 113.9 ksi is printed alongside
status: ground
source: haynes-c276
where: Tensile Strength and Elongation table, Plate, RT row
- benchmark: yield_strength
value: 225
unit: MPa
scope: material
conditions:
condition: mill annealed, the solution anneal (supply condition)
product: sheet, 2 mm (0.078 in) thick
temperature: 427 °C (800 °F)
offset: 0.2 percent
method: Haynes Tensile Strength and Elongation table, Sheet row at 800 F (427 C), MPa column; 32.7 ksi is printed alongside
status: ground
source: haynes-c276
where: Tensile Strength and Elongation table, Sheet, 800 F row
- benchmark: ultimate_tensile_strength
value: 650
unit: MPa
scope: material
conditions:
condition: mill annealed, the solution anneal (supply condition)
product: sheet, 2 mm (0.078 in) thick
temperature: 427 °C (800 °F)
method: Haynes Tensile Strength and Elongation table, Sheet row at 800 F (427 C), MPa column; 94.3 ksi is printed alongside
status: ground
source: haynes-c276
where: Tensile Strength and Elongation table, Sheet, 800 F row
- benchmark: hardness_rockwell_b
label: Rockwell B hardness, tungsten indenter (HRBW)
value: 88
unit: HRBW
scope: material
conditions:
condition: solution annealed (printed in the hardness table note)
product: sheet
method: Haynes Hardness table, Sheet row
status: ground
source: haynes-c276
where: Hardness table, Sheet row
- benchmark: hardness_rockwell_b
label: Rockwell B hardness, tungsten indenter (HRBW)
value: 86
unit: HRBW
scope: material
conditions:
condition: solution annealed (printed in the hardness table note)
product: bar
method: Haynes Hardness table, Bar row
status: ground
source: haynes-c276
where: Hardness table, Bar row
- benchmark: charpy_impact_energy
label: Charpy V-notch impact energy
value: 479
unit: J
scope: material
conditions:
temperature: room temperature
specimen: Charpy V-notch, mill annealed plate
basis: 353 ft-lbf is printed alongside
method: Haynes Impact Strength table, RT row, J column
status: ground
source: haynes-c276
where: Impact Strength table, RT row
- benchmark: charpy_impact_energy
label: Charpy V-notch impact energy
value: 519
unit: J
scope: material
conditions:
temperature: '-196 °C (-320 °F)'
specimen: Charpy V-notch, mill annealed plate
basis: 383 ft-lbf is printed alongside
method: Haynes Impact Strength table, -320 F row, J column
status: ground
source: haynes-c276
where: Impact Strength table, -320 F row
- benchmark: max_service_temp
value: 677
unit: °C
scope: material
conditions:
basis: '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 F'
condition: product forms as listed in the approval footnotes
method: Haynes Specifications and Codes page, Codes table, ASME Section VIII row
status: ground
note: A code approval temperature, not a test result. The brochure gives lower code limits for other codes, for example 1000 F for ASME Section I.
source: haynes-c276
where: Specifications and Codes page, Codes table, ASME Section VIII row
- benchmark: critical_pitting_temperature
label: Critical pitting temperature in acidified 6% ferric chloride
value: 150
bound: lower
unit: °C
scope: material
conditions:
test: ASTM G 48 in acidified 6 wt% ferric chloride; lowest temperature for attack within 72 hours
basis: printed as >150 C (>302 F)
method: Haynes Resistance to Pitting and Crevice Corrosion table, C-276 row
status: ground
source: haynes-c276
where: Resistance to Pitting and Crevice Corrosion table, C-276 row
- benchmark: critical_crevice_temperature
label: Critical crevice temperature in acidified 6% ferric chloride
value: 55
unit: °C
scope: material
conditions:
test: ASTM G 48 in acidified 6 wt% ferric chloride; within 72 hours
basis: printed as 131 F
method: Haynes Resistance to Pitting and Crevice Corrosion table, C-276 row
status: ground
source: haynes-c276
where: Resistance to Pitting and Crevice Corrosion table, C-276 row
- benchmark: density
value: 8.9
unit: g/cm3
scope: material
conditions:
basis: typical value; temperature not stated
method: ATI TDS, Physical Properties, Density; 0.321 lb/in3 is printed alongside
status: ground
note: ATI prints 8.90 and Haynes prints 8.89. Both are kept with their own sources.
source: ati-tds
where: Physical Properties, Density
- benchmark: electrical_resistivity
value: 130
unit: microhm-cm
scope: material
conditions:
temperature: 70 F (21 C)
basis: typical value
method: ATI TDS, Physical Properties, Electrical Resistivity
status: ground
note: Haynes prints 1.23 μohm.m at room temperature in a different unit. Both values are kept as printed.
source: ati-tds
where: Physical Properties, Electrical Resistivity
- benchmark: thermal_conductivity
value: 7.3
unit: W/m•K
scope: material
conditions:
temperature: '-168 °C (-270 °F)'
basis: typical value; no test condition printed in the table
method: ATI TDS, Thermal Conductivity table, -270 F row, W/m K column
status: ground
source: ati-tds
where: Physical Properties, Thermal Conductivity table, -270 F row
- benchmark: thermal_conductivity
value: 19
unit: W/m•K
scope: material
conditions:
temperature: 538 °C (1000 °F)
basis: typical value; no test condition printed in the table
method: ATI TDS, Thermal Conductivity table, 1000 F row, W/m K column
status: ground
source: ati-tds
where: Physical Properties, Thermal Conductivity table, 1000 F row
- benchmark: yield_strength
value: 283
bound: lower
unit: MPa
scope: material
conditions:
specification: ASTM B 575 minimum for plate, sheet and strip, as printed by ATI
condition: 'solution-annealed (ATI: all forms are furnished solution-annealed)'
temperature: room temperature
offset: 0.2 percent
method: ATI TDS, Minimum Properties (ASTM B 575) table; 41,000 psi (283 MPa) is printed
status: ground
note: Specification minimum, not a typical value.
source: ati-tds
where: Mechanical Properties, Minimum Properties (ASTM B 575) table
- benchmark: ultimate_tensile_strength
value: 690
bound: lower
unit: MPa
scope: material
conditions:
specification: ASTM B 575 minimum for plate, sheet and strip, as printed by ATI
condition: 'solution-annealed (ATI: all forms are furnished solution-annealed)'
temperature: room temperature
method: ATI TDS, Minimum Properties (ASTM B 575) table; 100,000 psi (690 MPa) is printed
status: ground
note: Specification minimum, not a typical value.
source: ati-tds
where: Mechanical Properties, Minimum Properties (ASTM B 575) table
- benchmark: elongation
value: 40
bound: lower
unit: '%'
scope: material
conditions:
specification: ASTM B 575 minimum for plate, sheet and strip, as printed by ATI
condition: 'solution-annealed (ATI: all forms are furnished solution-annealed)'
gauge: 2 inch
method: ATI TDS, Minimum Properties (ASTM B 575) table; elongation in 2 inch, minimum 40 percent
status: ground
note: Specification minimum, not a typical value.
source: ati-tds
where: Mechanical Properties, Minimum Properties (ASTM B 575) table
- benchmark: yield_strength
value: 565
unit: MPa
scope: material
conditions:
temperature: '-196 °C (-320 °F)'
condition: annealed at 2100 F (1150 C) and water quenched (ATI test material)
basis: typical short-time tensile value
offset: 0.2 percent
method: ATI TDS, short-time tensile table, -320 F row, 0.2 percent yield, MPa
status: ground
source: ati-tds
where: Mechanical Properties, short-time tensile table, -320 F row
- benchmark: ultimate_tensile_strength
value: 965
unit: MPa
scope: material
conditions:
temperature: '-196 °C (-320 °F)'
condition: annealed at 2100 F (1150 C) and water quenched (ATI test material)
basis: typical short-time tensile value
method: ATI TDS, short-time tensile table, -320 F row, tensile strength, MPa
status: ground
source: ati-tds
where: Mechanical Properties, short-time tensile table, -320 F row
- benchmark: elongation
value: 45
unit: '%'
scope: material
conditions:
temperature: '-196 °C (-320 °F)'
condition: annealed at 2100 F (1150 C) and water quenched (ATI test material)
basis: typical short-time tensile value
method: ATI TDS, short-time tensile table, -320 F row, elongation
status: ground
source: ati-tds
where: Mechanical Properties, short-time tensile table, -320 F row
- benchmark: yield_strength
value: 415
unit: MPa
scope: material
conditions:
temperature: 21 °C (70 °F)
condition: annealed at 2100 F (1150 C) and water quenched (ATI test material)
basis: typical short-time tensile value
offset: 0.2 percent
method: ATI TDS, short-time tensile table, 70 F row, 0.2 percent yield, MPa
status: ground
source: ati-tds
where: Mechanical Properties, short-time tensile table, 70 F row
- benchmark: ultimate_tensile_strength
value: 790
unit: MPa
scope: material
conditions:
temperature: 21 °C (70 °F)
condition: annealed at 2100 F (1150 C) and water quenched (ATI test material)
basis: typical short-time tensile value
method: ATI TDS, short-time tensile table, 70 F row, tensile strength, MPa
status: ground
source: ati-tds
where: Mechanical Properties, short-time tensile table, 70 F row
- benchmark: yield_strength
value: 270
unit: MPa
scope: material
conditions:
temperature: 538 °C (1000 °F)
condition: annealed at 2100 F (1150 C) and water quenched (ATI test material)
basis: typical short-time tensile value
offset: 0.2 percent
method: ATI TDS, short-time tensile table, 1000 F row, 0.2 percent yield, MPa
status: ground
source: ati-tds
where: Mechanical Properties, short-time tensile table, 1000 F row
- benchmark: ultimate_tensile_strength
value: 640
unit: MPa
scope: material
conditions:
temperature: 538 °C (1000 °F)
condition: annealed at 2100 F (1150 C) and water quenched (ATI test material)
basis: typical short-time tensile value
method: ATI TDS, short-time tensile table, 1000 F row, tensile strength, MPa
status: ground
source: ati-tds
where: Mechanical Properties, short-time tensile table, 1000 F row
- benchmark: charpy_impact_energy
label: Charpy V-notch impact energy, full thickness
value: 245
unit: J
scope: material
conditions:
temperature: '-196 °C (-320 °F)'
specimen: full thickness 10 mm sample from annealed plate
basis: 180 ft-lbs is printed alongside
method: ATI TDS, Impact Resistant table, -320 F row, Joules column
status: ground
source: ati-tds
where: Mechanical Properties, Impact Resistant table, -320 F row
- benchmark: charpy_impact_energy
label: Charpy V-notch impact energy, full thickness
value: 325
unit: J
scope: material
conditions:
temperature: 21 °C (70 °F)
specimen: full thickness 10 mm sample from annealed plate
basis: 240 ft-lbs is printed alongside
method: ATI TDS, Impact Resistant table, 70 F row, Joules column
status: ground
source: ati-tds
where: Mechanical Properties, Impact Resistant table, 70 F row
corrosion:
- environment: Nitric acid, 65 wt%, at 66 C to the boil (strongly oxidising)
headline: 'Corrosion rises steeply with heat in concentrated nitric acid: 0.41 mm/y at 66 C and 22.12 mm/y at the boil.'
effect: '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.'
rating: severe
conditions:
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'
source: haynes-c276
where: Selected Corrosion Data, Nitric Acid table, 65 wt% row
- environment: Chromic acid, 20 wt%, at 66 C (oxidising)
headline: Chromic acid at 66 C corrodes the alloy at 0.53 mm/y.
effect: Haynes reagent-grade test gives 0.53 mm/y for 20 percent chromic acid at 66 C.
rating: severe
conditions:
basis: reagent-grade solution, laboratory test
rating_basis: 'Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe'
source: haynes-c276
where: Selected Corrosion Data (Reagent Grade Solutions), Chromic Acid row
- environment: Hydrochloric acid, 10 wt%, at 38 C (reducing)
headline: Dilute hydrochloric acid at 38 C gives 0.17 mm/y.
effect: 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.
rating: moderate
conditions:
basis: reagent-grade acid, laboratory test
rating_basis: 'Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe'
source: haynes-c276
where: Selected Corrosion Data, Hydrochloric Acid table, 10 wt% row
- environment: Hydrochloric acid, 5 wt%, at the boil (reducing)
headline: Boiling 5 percent hydrochloric acid corrodes at 3.63 mm/y.
effect: 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.
rating: severe
conditions:
basis: reagent-grade acid, laboratory test
rating_basis: 'Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe'
source: haynes-c276
where: Selected Corrosion Data, Hydrochloric Acid table, 5 wt% row
- environment: Sulfuric acid, 10 wt%, at the boil (reducing)
headline: Boiling 10 percent sulfuric acid gives 0.18 mm/y.
effect: Haynes gives 0.18 mm/y at boiling for 10 percent sulfuric acid, and 0.14 mm/y at 93 C.
rating: moderate
conditions:
basis: reagent-grade acid, laboratory test
rating_basis: 'Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe'
source: haynes-c276
where: Selected Corrosion Data, Sulfuric Acid table, 10 wt% row
- environment: Sulfuric acid, 60 wt%, at the boil (reducing)
headline: Concentrated sulfuric acid at the boil corrodes at 13.08 mm/y.
effect: 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.
rating: severe
conditions:
basis: reagent-grade acid, laboratory test
rating_basis: 'Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe'
source: haynes-c276
where: Selected Corrosion Data, Sulfuric Acid table, 60 wt% row
- environment: Phosphoric acid, 85 wt%, at 149 C
headline: Phosphoric acid at 149 C corrodes at 0.29 mm/y.
effect: Haynes gives 0.29 mm/y for 85 percent phosphoric acid at 149 C, and 1.68 mm/y at the boil.
rating: moderate
conditions:
basis: reagent-grade acid, laboratory test
rating_basis: 'Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe'
source: haynes-c276
where: Selected Corrosion Data, Phosphoric Acid table, 85 wt% row
- environment: Hydrofluoric acid, 10 wt%, at 52 C
headline: Hydrofluoric acid at 52 C gives 0.41 mm/y of external attack; it can also cause internal attack.
effect: 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.
rating: moderate
conditions:
basis: reagent-grade acid, laboratory test
rating_basis: 'Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe'
source: haynes-c276
where: Selected Corrosion Data (Reagent Grade Solutions), Hydrofluoric Acid rows and footnote
- environment: Weld metal in sulfuric and hydrochloric acid
headline: '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.'
effect: 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.
rating: moderate
conditions:
basis: all-weld-metal samples from multiple gas metal arc passes
rating_basis: 'Haynes bands: under 0.1 mm/y low, 0.1 to 0.5 mm/y moderate, over 0.5 mm/y severe'
source: haynes-c276
where: Corrosion Resistance of Welds table
- environment: Chloride pitting and crevice attack in acidified 6 wt% ferric chloride (ASTM G 48), and Green and Yellow Death tests
headline: Critical pitting temperature above 150 C and critical crevice temperature 55 C for C-276 (Haynes).
effect: 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.
rating: low
conditions:
test: ASTM G 48 in acidified 6 wt% ferric chloride for 72 hours; Green and Yellow Death tests for 24 hours
source: haynes-c276
where: Resistance to Pitting and Crevice Corrosion table and text
- environment: Chloride stress-corrosion cracking, boiling 45 wt% magnesium chloride (ASTM G 36, U-bend samples)
headline: No cracking in 1,008 hours in boiling 45 percent magnesium chloride (Haynes).
effect: 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.
rating: none
conditions:
test: ASTM G 36, boiling 45 percent magnesium chloride, stressed U-bend samples, 1008 hours
source: haynes-c276
where: Resistance to Stress Corrosion Cracking table
- environment: Seawater crevice attack, still and flowing seawater (LaQue test, 180 days)
headline: Maximum crevice depth 0.13 mm in still seawater after 180 days; no attack in flowing seawater.
effect: 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.
rating: low
conditions:
temperature: 29 C plus or minus 3 C
exposure: 180 days, still and flowing seawater
source: haynes-c276
where: Resistance to Seawater Crevice Corrosion table
- environment: Most strongly oxidising acids, such as hot concentrated nitric acid
headline: ATI says the alloy has too little chromium for hot concentrated nitric acid.
effect: 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.
rating: severe
conditions:
basis: qualitative statement; no concentration or temperature printed
source: ati-tds
where: Corrosion Resistance, General Corrosion, page 2
- environment: Wet chlorine service
headline: ATI says it is one of the few materials able to resist wet chlorine.
effect: 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.
rating: low
conditions:
basis: qualitative statement; no rate printed
source: ati-tds
where: Corrosion Resistance, General Corrosion, page 2
- environment: Boiling Green Death scrubber solution (7% sulfuric acid, 3% hydrochloric acid, 1% cupric chloride, 1% ferric chloride)
headline: In boiling Green Death solution ATI 276 corrodes at 26.5 mpy (0.67 mm/a); Type 316 is destroyed.
effect: 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.
rating: severe
conditions:
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'
source: ati-tds
where: Corrosion Resistance, Green Death chart, page 3
- environment: Chloride stress-corrosion cracking in boiling 42 percent magnesium chloride, 33 percent lithium chloride and 26 percent sodium chloride
headline: ATI reports resistance for 1000 hours in each boiling chloride solution.
effect: 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.
rating: none
conditions:
basis: U-bend samples; boiling solutions
source: ati-tds
where: Chloride Stress Corrosion table, page 3
- environment: Seawater and brine (qualitative), and ferric chloride crevice test at 10 percent with 6 percent water
headline: ATI calls the alloy inert to seawater; crevice attack starts at 60 C in its ferric chloride test.
effect: 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.
rating: low
conditions:
basis: qualitative seawater statement; ASTM G 48 Practice B onset temperature
source: ati-tds
where: Pitting and Crevice Corrosion, page 3
- environment: 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)
headline: 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.
effect: 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.
rating: unknown
conditions:
basis: acceptance-test rates; the criteria differ from the mm/y bands used for the other ratings
source: ati-tds
where: Corrosion Resistance, independent laboratory study, Solutions 1 and 2, page 4
- environment: Nuclear-waste off-gas and condensate test (3 B-2 solution, boiling, 10 days)
headline: Corrosion under 1.5 mpy and crevice attack under 1 mil in the 3 B-2 test required by the nuclear-waste project.
effect: 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.
rating: low
conditions:
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'
source: ati-tds
where: Corrosion Resistance, Solution 3 and 3 B-2 table, pages 4 and 5
risks:
hazards:
- text: 'PubChem aggregated GHS for nickel metal, from 4778 reports and 86 ECHA C&L notifications: H317 (99.9%), H351 (72.9%), H372 (99.7%), H350 (22.5%), H360F (18%), H341 (13.5%), H334 (10.3%) and H412 (47.2%). The record is for nickel, which is about 57 percent of this alloy (Haynes nominal), not for the alloy itself.'
ghs:
- H317
- H351
- H372
- H350
- H360F
- H341
- H334
- H412
source: pubchem-nickel
where: Safety and Hazards, GHS Classification (aggregated ECHA C&L notifications)
- text: 'Hydrofluoric acid, the acid that ATI pairs with nitric acid for pickling this alloy: H300 fatal if swallowed (99.8%), H310 fatal in contact with skin (99.8%), H330 fatal if inhaled (99.8%), H314 severe skin burns and eye damage (over 99.9%) and H318 serious eye damage (19.4%). This is the hazard of the acid, not of the alloy.'
ghs:
- H300
- H310
- H314
- H318
- H330
source: pubchem-hf
where: Safety and Hazards, GHS Classification (CID 14917, Hydrofluoric Acid)
- text: For the element concentrations of a particular product and the potential health effects, Haynes refers readers to its safety data sheets. No safety data sheet for this alloy was found in this run, so the solid-alloy hazard rests on the nickel record.
ghs: []
source: haynes-c276
where: Disclaimer, last page of the brochure
failure_risks:
- mode: Loss of important properties from raised carbon or silicon
trigger: Fabrication that raises the low carbon and silicon contents, such as oxyacetylene welding or carbon- or silicon-bearing fluxes
consequence: ATI says raising the low carbon and silicon contents may adversely affect important properties of the alloy.
severity: moderate
source: ati-tds
where: Introduction, page 1; Weldability, page 7
- mode: Embrittling precipitates at high temperature
trigger: Long exposure at high temperature; ATI prints no time or temperature
consequence: ATI says the alloy will eventually form embrittling high-temperature precipitates, although it has good high-temperature strength and moderate oxidation resistance.
severity: moderate
source: ati-tds
where: Introduction, page 1
- mode: Loss of stress-corrosion resistance after cold work
trigger: Cold work that gives 7 percent or more outer-fibre elongation without a re-anneal
consequence: Haynes says cold work can affect resistance to stress-corrosion cracking, and that re-annealing restores optimum properties.
severity: moderate
source: haynes-c276
where: Welding and Fabrication section
- mode: Strength gain and ductility loss from cold reduction
trigger: Cold reduction of sheet by 50 percent
consequence: ATI'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.
severity: moderate
source: ati-tds
where: Cold Working table, page 7
- mode: Attack by hot, concentrated nitric acid
trigger: Hot concentrated nitric acid, for example boiling 65 percent acid
consequence: Haynes 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.
severity: high
source: haynes-c276
where: Selected Corrosion Data, Nitric Acid table
- mode: Narrow hot-working window
trigger: Hot working outside the recommended range, from 1232 C (2250 F) to 954 C (1750 F) for forging
consequence: Haynes says the alloy is more sensitive to strain and strain rate than austenitic stainless steels, and that its hot-working range is quite narrow.
severity: moderate
source: haynes-c276
where: Welding and Fabrication section
side_effects: []
handling:
- text: 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).
source: haynes-c276
where: Welding and Fabrication section
- text: Solution heat-treat at 1040 to 1150 C (1900 to 2100 F) and cool to black in two minutes or less (ATI).
source: ati-tds
where: Heat Treatment, page 8
- text: Clean the material before heat treatment and keep it free of grease, oils and other carbon sources (ATI).
source: ati-tds
where: Heat Treatment, page 8
- text: Stress-relief heat treatments are not effective for this alloy; a full anneal should be used instead (ATI).
source: ati-tds
where: Heat Treatment, page 8
- text: Descale with stainless wire brushing or grit blasting, then immerse in a mixture of nitric and hydrofluoric acids and rinse thoroughly with water (ATI).
source: ati-tds
where: Descaling and Cleaning, page 8
- text: 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).
source: haynes-c276
where: Welding and Fabrication section
mitigations:
- text: Re-anneal cold-worked parts after an outer-fibre elongation of 7 percent or more to restore corrosion and stress-corrosion performance (Haynes).
source: haynes-c276
where: Welding and Fabrication section
- text: 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).
source: ati-tds
where: Post Weld Heat Treatment, page 8
- text: 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).
source: ati-tds
where: Weld Wire and Filler, page 8
- text: Avoid oxyacetylene welding and submerged-arc fluxes that contain carbon or silicon, because they cause carbon pick-up (ATI).
source: ati-tds
where: Weldability, page 7
uses:
- application: structures
device: Reactors, heat exchangers and columns in chemical process plants
example: Haynes says typical chemical process industry applications include reactors, heat exchangers and columns. ATI says the alloy is widely used in chemical and petrochemical processing.
source: haynes-c276
where: Principal Features, page 1
- application: structures
device: Outlet ducting in flue-gas desulfurization systems
example: ATI says one application is in the more corrosive area of flue-gas desulfurization systems, such as outlet ducting.
source: ati-tds
where: General Corrosion, page 2
- application: structures
device: Off-gas line and condensate storage tank for nuclear-waste vitrification (Savannah River Plant)
example: ATI says over 1,000 tons of UNS N10276 alloy were supplied for this project, based on the alloy passing the 10-day three B-2 test.
source: ati-tds
where: Corrosion Resistance, Solution 3, page 4
supply:
- subject: Nickel
abundance: Globally, nickel resources have been estimated to contain more than 350 million tons of nickel (USGS)
producers:
- country: Indonesia
share_percent: 66.7
year: 2025
- country: Philippines
share_percent: 6.9
year: 2025
- country: Russia
share_percent: 5.1
year: 2025
- country: Canada
share_percent: 3.6
year: 2025
critical_lists: []
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.'
source: usgs-mcs2026-nickel
where: World Mine Production and Reserves table, 2025e column; shares calculated by Space Mushroom against the printed world total of 3,900,000 t (not printed as shares); Recycling; Substitutes; World Resources
- subject: Molybdenum
abundance: Identified resources in the United States are about 5.4 million tons and, in the rest of the world, about 20 million tons (USGS)
producers:
- country: China
share_percent: 37.3
year: 2025
- country: Chile
share_percent: 16.2
year: 2025
- country: United States
share_percent: 15.4
year: 2025
- country: Peru
share_percent: 15
year: 2025
- country: Mexico
share_percent: 6.5
year: 2025
critical_lists: []
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.'
source: usgs-mcs2026-molybdenum
where: World Mine Production and Reserves table, 2025e column; shares calculated by Space Mushroom against the printed world total of 260,000 t (not printed as shares); Recycling; Substitutes; World Resources
- subject: Chromium
abundance: World resources are greater than 12 billion tons of shipping-grade chromite (USGS)
producers:
- country: South Africa
share_percent: 45.1
year: 2025
- country: Turkey
share_percent: 17.6
year: 2025
- country: Kazakhstan
share_percent: 13.7
year: 2025
- country: India
share_percent: 5.9
year: 2025
critical_lists: []
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.'
source: usgs-mcs2026-chromium
where: World Mine Production and Reserves table, 2025e column; shares calculated by Space Mushroom against the printed world total of 51,000 thousand t (not printed as shares); Recycling; Substitutes; World Resources
- subject: Tungsten
abundance: World tungsten resources are geographically widespread, and China ranked first in resources and reserves (USGS)
producers:
- country: China
share_percent: 78.8
year: 2025
- country: Vietnam
share_percent: 3.5
year: 2025
- country: Kazakhstan
share_percent: 2.8
year: 2025
- country: Russia
share_percent: 2.4
year: 2025
critical_lists: []
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.'
source: usgs-mcs2026-tungsten
where: World Mine Production and Reserves table, 2025 column; shares calculated by Space Mushroom against the printed world total of 85,000 t (not printed as shares); Substitutes; World Resources
media: []
documents:
- title: HASTELLOY C-276 alloy brochure H-2002H, Haynes International (2023)
type: datasheet
url: https://haynesintl.com/wp-content/uploads/2024/08/c-276.pdf
year: 2023
- title: ATI 276 Technical Data Sheet, version 1 (2014)
type: datasheet
url: https://www.atimaterials.com/Products/Documents/datasheets/nickel-cobalt/nickel-based/ati_276_tds_en_v1.pdf
year: 2014
- title: 'USGS Mineral Commodity Summaries 2026: Nickel'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf
year: 2026
- title: 'USGS Mineral Commodity Summaries 2026: Molybdenum'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-molybdenum.pdf
year: 2026
- title: 'USGS Mineral Commodity Summaries 2026: Chromium'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf
year: 2026
- title: 'USGS Mineral Commodity Summaries 2026: Tungsten'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-tungsten.pdf
year: 2026
- title: 'PubChem: Nickel (CID 935), GHS classification'
type: database
url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/935/JSON?heading=GHS+Classification
- title: 'PubChem: Hydrofluoric Acid (CID 14917), GHS classification'
type: database
url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/14917/JSON?heading=GHS+Classification
gaps:
- No ASTM B 575 or B 574 composition limits (minimum and maximum for Cr, Mo, W, Fe and Ni) were printed on the pages read. Haynes gives nominal values for Ni, Cr, Mo, Fe and W and maximum limits for Co, Mn, V, Si, C and Cu; ATI gives typical values only, which are not limits.
- The Haynes physical-property table does not restate the heat-treatment condition. The brochure says wrought products are supplied mill annealed unless otherwise specified, and that supply condition is recorded in conditions.
- No safety data sheet for this alloy was found. The Haynes and ATI SDS index pages list no C-276 sheet. Hazards for the solid alloy rest on the PubChem nickel record (nickel is about 57 percent of the alloy); the hydrofluoric acid record covers the pickling step.
- The application list has no chemical-process, flue-gas or nuclear-waste slug. Those uses are filed under structures, the nearest slug. No space use, flight result, vacuum, radiation or space-environment data was found for this alloy.
- No creep, rupture, long-term ageing or oxidation-rate data were read. ATI says the alloy has moderate oxidation resistance and will eventually form embrittling precipitates, but prints no time or temperature. Haynes prints code temperature limits from 343 C to 677 C depending on the code; 677 C (1250 F) is the highest.
- 'The VDM Alloy C-276 datasheet (Nicrofer C 276) could not be read: the VDM page returned a bot check to curl and a 404 in the browser. The USGS 2025 critical-minerals page returned 403, so no critical-list status was recorded for any commodity.'
- Weld data are limited to corrosion of all-weld-metal samples (Haynes). No weld strength or weld toughness numbers were printed in the pages read.
- Charpy impact energy, Rockwell B hardness, critical pitting temperature and critical crevice temperature have no canonical name in property-canon, so snake_case names are used for them.
- 'ATI''s thermal conductivity row for -100 F is left out: its printed Celsius value (73) does not match -100 F, which is about -73 C.'
- Corrosion values are laboratory results in reagent-grade solutions (Haynes) or typical test results (ATI), not field data. The ATI ASTM G28 rates are not on the same mm/y bands, so their rating is unknown and the criterion ATI prints is given instead.
- Producer shares for nickel, molybdenum, chromium and tungsten are calculated from the printed world totals; USGS does not print them as percentages.
- 'Designations: DIN 2.4886 and 2.4887 and the AWS A5.11 and A5.14 filler classes belong to welding consumables, so they are not listed as designations of the base alloy. W10276 is listed as a product form printed beside N10276 by Haynes.'
- Density and electrical resistivity differ between sources (Haynes 8.89 g/cm3 and 1.23 μohm.m; ATI 8.90 g/cm3 and 130 microhm-cm, typical). Both sets are kept with their own sources.
- Side effects on the surroundings (gases, leachates or dust from the solid alloy) were not printed in the sources read.
- Wikipedia (Haynes International, the page the Hastelloy name redirects to) gives only the brand history; no composition or property number was taken from it.
sources:
haynes-c276:
title: HASTELLOY C-276 alloy, Haynes International brochure H-2002H
id: Haynes International, document H-2002H, copyright 2023
url: https://haynesintl.com/wp-content/uploads/2024/08/c-276.pdf
year: 2023
kind: datasheet
license: Haynes terms (cited, not reproduced)
ati-tds:
title: ATI 276 Technical Data Sheet (Nickel-base Alloy, UNS N10276)
id: ATI Allegheny Technologies, version 1 (2/17/2014)
url: https://www.atimaterials.com/Products/Documents/datasheets/nickel-cobalt/nickel-based/ati_276_tds_en_v1.pdf
year: 2014
kind: datasheet
license: ATI terms (cited, not reproduced)
usgs-mcs2026-nickel:
title: 'Mineral Commodity Summaries 2026: Nickel'
id: USGS, Mineral Commodity Summaries, February 2026
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf
year: 2026
kind: report
license: public domain (USGS)
usgs-mcs2026-molybdenum:
title: 'Mineral Commodity Summaries 2026: Molybdenum'
id: USGS, Mineral Commodity Summaries, February 2026
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-molybdenum.pdf
year: 2026
kind: report
license: public domain (USGS)
usgs-mcs2026-chromium:
title: 'Mineral Commodity Summaries 2026: Chromium'
id: USGS, Mineral Commodity Summaries, February 2026
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf
year: 2026
kind: report
license: public domain (USGS)
usgs-mcs2026-tungsten:
title: 'Mineral Commodity Summaries 2026: Tungsten'
id: USGS, Mineral Commodity Summaries, February 2026
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-tungsten.pdf
year: 2026
kind: report
license: public domain (USGS)
pubchem-nickel:
title: 'PubChem: Nickel (CID 935), GHS classification (aggregated ECHA C&L notifications)'
id: PubChem CID 935
url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/935/JSON?heading=GHS+Classification
kind: database
license: public domain (NIH)
pubchem-hf:
title: 'PubChem: Hydrofluoric Acid (CID 14917), GHS classification'
id: PubChem CID 14917
url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/14917/JSON?heading=GHS+Classification
kind: database
license: public domain (NIH)
wiki-haynes:
title: Haynes International (Wikipedia; the Hastelloy name redirects here; first Hastelloy alloy invented in 1922)
id: Wikipedia, English article, read 2026-10-24
url: https://en.wikipedia.org/wiki/Haynes_International
kind: web
license: CC BY-SA 4.0
license: CC-BY-4.0
updated: '2026-10-24'
review:
status: draft
method: assistant
checked_values: 41
unreachable: 0
caveats: 6
note: 'Written by an AI assistant on 2026-10-24. Every number was read from a page or PDF fetched in this run: the Haynes C-276 brochure H-2002H (2023), the ATI 276 TDS (version 1, 2014), USGS MCS 2026 for nickel, molybdenum, chromium and tungsten, PubChem (nickel and hydrofluoric acid GHS) and Wikipedia (brand history only). Sources were reached by following links from the Haynes portfolio index and the C-276 product page.'
story:
why: '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).'
recipe:
line: 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.
parts:
- name: Nickel
symbol: Ni
share_percent: 57
share_note: balance; Haynes nominal 57 wt%
role: Matrix of the alloy. With molybdenum it gives extreme resistance to chloride stress-corrosion cracking (ATI).
source: haynes-c276
where: Nominal Composition table
- name: Chromium
symbol: Cr
share_percent: 16
share_note: nominal; ATI typical 15.50
role: Gives resistance to oxidising conditions, but ATI says it is too low for hot concentrated nitric acid.
source: haynes-c276
where: Nominal Composition table
- name: Molybdenum
symbol: Mo
share_percent: 16
share_note: nominal; ATI typical 16.0
role: Gives resistance to pitting and crevice attack and to non-oxidising acids (Haynes; ATI).
source: haynes-c276
where: Nominal Composition table
- name: Tungsten
symbol: W
share_percent: 4
share_note: nominal; ATI typical 3.50
role: Adds to the pitting resistance that chromium and molybdenum give (ATI).
source: haynes-c276
where: Nominal Composition table
- name: Iron
symbol: Fe
share_percent: 5
share_note: nominal; ATI typical 6.00
role: Present in the nominal composition; the fetched sources give it no role.
source: haynes-c276
where: Nominal Composition table
- name: Cobalt
symbol: Co
share_note: 2.5 maximum (Haynes); ATI typical 0.10
role: Present up to the maximum; the fetched sources give it no role.
source: haynes-c276
where: Nominal Composition table, maximum
- name: Manganese
symbol: Mn
share_note: 1 maximum (Haynes); ATI typical 0.150
role: Present up to the maximum; the fetched sources give it no role.
source: haynes-c276
where: Nominal Composition table, maximum
- name: Vanadium
symbol: V
share_note: 0.35 maximum (Haynes); ATI typical 0.15
role: Present up to the maximum; the fetched sources give it no role.
source: haynes-c276
where: Nominal Composition table, maximum
- name: Silicon
symbol: Si
share_note: 0.08 maximum (Haynes); ATI typical 0.03
role: 'Kept very low: Haynes ties the low silicon and carbon to easier welding, and ATI warns that raising them may adversely affect properties.'
source: haynes-c276
where: Nominal Composition table, maximum
- name: Carbon
symbol: C
share_note: 0.01 maximum (Haynes); ATI typical 0.006
role: Kept very low for welding; ATI warns that raising it may adversely affect properties.
source: haynes-c276
where: Nominal Composition table, maximum
- name: Copper
symbol: Cu
share_note: 0.5 maximum (Haynes)
role: Present up to the maximum; the fetched sources give it no role.
source: haynes-c276
where: Nominal Composition table, maximum
risk_groups:
- title: For people
level: 2
verdict: Nickel record flags hazards; pickling acid is severe
lead: 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.
points:
- label: Solid alloy
line: 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).
- label: Pickling acid
line: 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).
- title: If a part stays hot too long
lead: These results come from the datasheets, not from field incidents.
points:
- label: Heat exposure
line: ATI says the alloy will eventually form embrittling high-temperature precipitates, but it gives no time or temperature for them to form.
- label: Code approval
line: 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.
- title: Handling and heat treatment
verdict: Anneal and re-anneal protect corrosion resistance
points:
- label: Anneal
line: 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).
- label: Pickling
line: Remove scale with wire brushing or grit blasting, then nitric and hydrofluoric acids, and rinse well (ATI).
uses:
- where: Chemical plants
line: Haynes names reactors, heat exchangers and columns as typical chemical process uses. ATI calls the alloy widely used in chemical and petrochemical processing.
- where: Flue-gas desulfurization
line: 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.
- where: Nuclear-waste processing
line: 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.
- where: Sour oil and gas
line: Haynes lists the alloy under NACE MR0175 and says it is very resistant to sulfide stress cracking in sour oilfield environments.
can_do:
- label: Pitting and crevice attack
line: 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.
value: Above 150 C
- label: Chloride stress cracking
line: 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.
value: No cracking in 1,008 hours
- label: Acids, reducing and oxidising
line: 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.
value: 0.17 to 0.53 mm/y
- label: Strength at -196 C
line: ATI's typical tensile test gives 965 MPa at -196 C with 45 percent elongation, after annealing at 2100 F and water quenching.
value: 965 MPa
- label: Welding
line: 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.
value: 0.13 mm/y
compare: 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.
compare_rows:
- label: Density
benchmark: density
- label: Melting range
benchmark: melting_point
- label: Yield strength
benchmark: yield_strength
handling:
- Solution anneal at 1121 C (2050 F) for 10 to 30 minutes, then water quench. Rapid air cooling is possible only for sections thinner than 10 mm (Haynes).
- Re-anneal after hot forming, and after cold work that gives 7 percent or more outer-fibre elongation (Haynes).
- Hot forge from 1232 C (2250 F) down to 954 C (1750 F). The hot-working range is narrow (Haynes).
- Stress-relief treatments are not effective; use a full anneal instead (ATI).
- Descale with wire brushing or grit blasting, then nitric and hydrofluoric acids, and rinse well (ATI).
- Avoid oxyacetylene welding and carbon- or silicon-bearing fluxes, which pick up carbon (ATI).
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:
- '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.
verdict: 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.
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
| # | Source | Type | Year | Used for |
|---|---|---|---|---|
| HASTELLOY C-276 alloy, Haynes International brochure H-2002H | datasheet | 2023 | 46 values | |
| ATI 276 Technical Data Sheet (Nickel-base Alloy, UNS N10276) | datasheet | 2014 | 35 values | |
| Mineral Commodity Summaries 2026: Nickel | report | 2026 | 1 value | |
| Mineral Commodity Summaries 2026: Molybdenum | report | 2026 | 1 value | |
| Mineral Commodity Summaries 2026: Chromium | report | 2026 | 1 value | |
| Mineral Commodity Summaries 2026: Tungsten | report | 2026 | 1 value | |
| PubChem: Nickel (CID 935), GHS classification (aggregated ECHA C&L notifications) | database | 1 value | ||
| PubChem: Hydrofluoric Acid (CID 14917), GHS classification | database | 1 value | ||
| Haynes International (Wikipedia; the Hastelloy name redirects here; first Hastelloy alloy invented in 1922) | web | 0 values |