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.