Hastelloy X X (UNS N06002)

spore: profile
id: hastelloy-x
spore_version: 0.2
family: nickel-alloys
name: Hastelloy X
abbreviation: X (UNS N06002)
role: oxidation-resistant nickel-chromium-iron-molybdenum alloy for hot gas-turbine and furnace parts
category: metals
type: nickel-superalloys
summary: |
  Hastelloy X (UNS N06002, EN 2.4665) is a nickel-chromium-iron-molybdenum alloy. Haynes describes it as having an exceptional combination of oxidation resistance, fabricability and high-temperature strength. Haynes gives a room-temperature density of 8.22 g/cm3 and a yield strength of 340 MPa for plate (solution heat-treated, 0.2 percent offset), which falls to 45 MPa at 2000 F (1093 C). The sources name gas-turbine combustion-zone parts, afterburners, tailpipes and industrial furnace parts. No spacecraft, rocket or satellite use was found in the sources read.
best_for: 'Hot oxidising gas and furnace service where the alloy must also be formed and welded: metal loss of 0.007 mm per side after 1008 h at 980 C in flowing air (Haynes)'
weakest_at: 'Strength at high temperature and after long ageing: plate yield falls from 340 MPa at room temperature to 189 MPa at 871 C (Haynes), and Charpy energy falls from 129 J to 16 J after 16,000 h at 871 C (Haynes)'
identity:
  formula: 'Nickel-chromium-iron-molybdenum alloy, UNS N06002. Haynes nominal composition in wt%: Ni 47 (balance), Cr 22.0, Fe 18.0, Mo 9.0, Co 1.5, W 0.6, C 0.1; maximum limits Mn 1, Si 1.0, B 0.008, Nb 0.5, Al 0.5, Ti 0.15. F&W Metals composition ranges in wt%: C 0.05-0.15, Cr 20.5-23.0, Fe 17.0-20.0, Mo 8.0-10.0, Co 0.5-2.5, W 0.20-1.0, Mn 1.00 max, Si 1.00 max, P 0.040 max, S 0.030 max.'
  source: haynes-x
  where: Nominal Composition table (Haynes product page); composition ranges in the F&W Metals chemical composition table
  designations:
    - system: UNS
      code: N06002
      source: haynes-x
      where: Principal Features, first sentence (UNS N06002 (W86002))
    - system: UNS
      code: W86002
      note: welding product form printed beside N06002
      source: haynes-x
      where: Specifications and Codes table heading (N06002, W86002)
    - system: EN
      code: '2.4665'
      source: haynes-x
      where: 'Specifications and Codes table, DIN row: 17742 No. 2.4665 NiCr22Fe18Mo'
    - system: EN name
      code: NiCr22Fe18Mo
      source: haynes-x
      where: Specifications and Codes table, DIN row
    - system: DIN
      code: '17742'
      note: standard that lists No. 2.4665 as NiCr22Fe18Mo
      source: haynes-x
      where: Specifications and Codes table, DIN row
    - system: AMS
      code: '5536'
      note: sheet, plate and strip
      source: haynes-x
      where: Specifications and Codes table, Sheet, Plate & Strip row
    - system: AMS
      code: '5754'
      note: billet, rod and bar, and forgings
      source: haynes-x
      where: Specifications and Codes table, Billet, Rod & Bar row
    - system: AMS
      code: '5588'
      note: welded pipe and tube
      source: haynes-x
      where: Specifications and Codes table, Welded Pipe & Tube row
    - system: ASTM
      code: B 435
      note: sheet, plate and strip
      source: haynes-x
      where: Specifications and Codes table, Sheet, Plate & Strip row (SB 435/B 435P)
    - system: ASTM
      code: B 572
      note: billet, rod and bar
      source: haynes-x
      where: Specifications and Codes table, Billet, Rod & Bar row (SB 572/B 572B)
    - system: ASTM
      code: B 619
      note: welded pipe and tube
      source: haynes-x
      where: Specifications and Codes table, Welded Pipe & Tube row (SB 619/B 619)
    - system: ASTM
      code: B 622
      note: seamless pipe and tube
      source: haynes-x
      where: Specifications and Codes table, Seamless Pipe & Tube row (SB 622/B 622)
    - system: ASTM
      code: B 626
      note: welded tube
      source: haynes-x
      where: Specifications and Codes table, Welded Pipe & Tube row (SB 626/B 626)
    - system: ASTM
      code: B 366
      note: fittings
      source: haynes-x
      where: Specifications and Codes table, Fittings row (SB 366/B 366)
    - system: ASME
      code: SB 435
      note: sheet, plate and strip
      source: haynes-x
      where: Specifications and Codes table, Sheet, Plate & Strip row
    - system: NACE
      code: MR0175
      note: sour-service listing
      source: haynes-x
      where: Specifications and Codes table, Others row
    - system: Trade name
      code: HASTELLOY® X
      source: haynes-x
      where: Page title and Principal Features
tags:
  environments: []
  stresses: []
  applications:
    - propulsion-and-tanks
    - structures
properties:
  - benchmark: density
    value: 8.22
    unit: g/cm3
    scope: material
    conditions:
      temperature: 22 C (72 F)
      unit_in_source: 0.297 lb/in3
    method: Value printed in the Physical Properties table of the Haynes product page
    status: ground
    source: haynes-x
    where: Physical Properties table, Density row, metric column
  - benchmark: melting_point
    value: 1260
    value_high: 1355
    bound: range
    unit: C
    scope: material
    conditions:
      basis: melting range
      unit_in_source: 2300 - 2470 F
    method: Melting range printed in the Physical Properties table of the Haynes product page
    status: ground
    source: haynes-x
    where: Physical Properties table, Melting Range row, metric column
  - benchmark: electrical_resistivity
    value: 114.83
    unit: µohm-cm
    scope: material
    conditions:
      temperature: 24 C (75 F)
      unit_in_source: 45.21 µohm-in
    method: Value printed in the Physical Properties table of the Haynes product page
    status: ground
    source: haynes-x
    where: Physical Properties table, Electrical Resistivity, 75 F / 24 C row
  - benchmark: thermal_conductivity
    value: 9.2
    unit: W/(m·K)
    scope: material
    conditions:
      temperature: 25 C (70 F)
      unit_in_source: W/m-C; 63 Btu-in/ft2-hr-F
    method: Value printed in the Physical Properties table of the Haynes product page
    status: ground
    source: haynes-x
    where: Physical Properties table, Thermal Conductivity, 70 F / 25 C row
  - benchmark: thermal_conductivity
    value: 26.7
    unit: W/(m·K)
    scope: material
    conditions:
      temperature: 900 C (1700 F)
      unit_in_source: W/m-C; 189 Btu-in/ft2-hr-F
    method: Value printed in the Physical Properties table of the Haynes product page
    status: ground
    source: haynes-x
    where: Physical Properties table, Thermal Conductivity, 1700 F / 900 C row
  - benchmark: specific_heat
    value: 486
    unit: J/(kg·K)
    scope: material
    conditions:
      temperature: room temperature
      unit_in_source: J/kg-C; 0.116 Btu/lb-F
    method: Value printed in the Physical Properties table of the Haynes product page
    status: ground
    source: haynes-x
    where: Specific Heat table, RT row, metric column
  - benchmark: cte
    value: 13.9
    unit: µm/(m·K)
    scope: material
    conditions:
      temperature_range: 26 to 100 C
      basis: mean coefficient from 26 C
      unit_in_source: 10-6 m/m-C
    method: Mean coefficient printed in the Physical Properties table of the Haynes product page
    status: ground
    source: haynes-x
    where: Mean Coefficient of Thermal Expansion table, 26 - 100 C row, metric column
  - benchmark: cte
    value: 16.4
    unit: µm/(m·K)
    scope: material
    conditions:
      temperature_range: 26 to 900 C
      basis: mean coefficient from 26 C
      unit_in_source: 10-6 m/m-C
    method: Mean coefficient printed in the Physical Properties table of the Haynes product page
    status: ground
    source: haynes-x
    where: Mean Coefficient of Thermal Expansion table, 26 - 900 C row, metric column
  - benchmark: elastic_modulus
    value: 205
    unit: GPa
    scope: material
    conditions:
      temperature: room temperature
      basis: dynamic modulus of elasticity
      unit_in_source: 29.8 x 10^6 psi
    method: Value printed in the Physical Properties table of the Haynes product page
    status: ground
    source: haynes-x
    where: Dynamic Modulus of Elasticity table, RT row, metric column
  - benchmark: elastic_modulus
    value: 148
    unit: GPa
    scope: material
    conditions:
      temperature: 900 C (1800 F)
      basis: dynamic modulus of elasticity
      unit_in_source: 20.4 x 10^6 psi at 1800 F
    method: Value printed in the Physical Properties table of the Haynes product page
    status: ground
    source: haynes-x
    where: Dynamic Modulus of Elasticity table, 900 C row, metric column
  - benchmark: poissons_ratio
    value: 0.32
    unit: '-'
    scope: material
    conditions:
      temperature: 22 C (72 F)
    method: Value printed in the Physical Properties table of the Haynes product page
    status: ground
    source: haynes-x
    where: Poisson's Ratio table, 72 F / 22 C row
  - benchmark: yield_strength
    value: 340
    unit: MPa
    scope: material
    conditions:
      form: plate
      temperature: room temperature (70 F / 21 C)
      condition: solution heat-treated, not aged (Haynes footnote); the tensile table heading does not restate the condition
      offset: 0.2 percent
      unit_in_source: 49.3 ksi
    method: Tensile value printed in the Haynes Tensile Data, Plate table
    status: ground
    source: haynes-x
    where: Tensile Data, Plate table, 70 F / 21 C row, 0.2% yield column
  - benchmark: ultimate_tensile_strength
    value: 760
    unit: MPa
    scope: material
    conditions:
      form: plate
      temperature: room temperature (70 F / 21 C)
      condition: solution heat-treated, not aged (Haynes footnote)
      unit_in_source: 110.2 ksi
    method: Tensile value printed in the Haynes Tensile Data, Plate table
    status: ground
    source: haynes-x
    where: Tensile Data, Plate table, 70 F / 21 C row, ultimate column
  - benchmark: elongation
    value: 48.9
    unit: '%'
    scope: material
    conditions:
      form: plate
      temperature: room temperature (70 F / 21 C)
      condition: solution heat-treated, not aged (Haynes footnote)
    method: Tensile value printed in the Haynes Tensile Data, Plate table
    status: ground
    source: haynes-x
    where: Tensile Data, Plate table, 70 F / 21 C row, elongation column
  - benchmark: yield_strength
    value: 376
    unit: MPa
    scope: material
    conditions:
      form: sheet
      temperature: room temperature (70 F / 21 C)
      condition: solution heat-treated, not aged (Haynes footnote)
      offset: 0.2 percent
      unit_in_source: 54.5 ksi
    method: Tensile value printed in the Haynes Tensile Data, Sheet table
    status: ground
    source: haynes-x
    where: Tensile Data, Sheet table, 70 F / 21 C row, 0.2% yield column
  - benchmark: ultimate_tensile_strength
    value: 783
    unit: MPa
    scope: material
    conditions:
      form: sheet
      temperature: room temperature (70 F / 21 C)
      condition: solution heat-treated, not aged (Haynes footnote)
      unit_in_source: 113.5 ksi
    method: Tensile value printed in the Haynes Tensile Data, Sheet table
    status: ground
    source: haynes-x
    where: Tensile Data, Sheet table, 70 F / 21 C row, ultimate column
  - benchmark: elongation
    value: 46.5
    unit: '%'
    scope: material
    conditions:
      form: sheet
      temperature: room temperature (70 F / 21 C)
      condition: solution heat-treated, not aged (Haynes footnote)
    method: Tensile value printed in the Haynes Tensile Data, Sheet table
    status: ground
    source: haynes-x
    where: Tensile Data, Sheet table, 70 F / 21 C row, elongation column
  - benchmark: yield_strength
    value: 241
    unit: MPa
    scope: material
    conditions:
      form: sheet
      temperature: 649 C (1200 F)
      condition: solution heat-treated, not aged (Haynes footnote)
      offset: 0.2 percent
      unit_in_source: 34.9 ksi
    method: Tensile value printed in the Haynes Tensile Data, Sheet table
    status: ground
    source: haynes-x
    where: Tensile Data, Sheet table, 1200 F / 649 C row, 0.2% yield column
  - benchmark: ultimate_tensile_strength
    value: 580
    unit: MPa
    scope: material
    conditions:
      form: sheet
      temperature: 649 C (1200 F)
      condition: solution heat-treated, not aged (Haynes footnote)
      unit_in_source: 84.2 ksi
    method: Tensile value printed in the Haynes Tensile Data, Sheet table
    status: ground
    source: haynes-x
    where: Tensile Data, Sheet table, 1200 F / 649 C row, ultimate column
  - benchmark: yield_strength
    value: 189
    unit: MPa
    scope: material
    conditions:
      form: plate
      temperature: 871 C (1600 F)
      condition: solution heat-treated, not aged (Haynes footnote)
      offset: 0.2 percent
      unit_in_source: 27.4 ksi
    method: Tensile value printed in the Haynes Tensile Data, Plate table
    status: ground
    source: haynes-x
    where: Tensile Data, Plate table, 1600 F / 871 C row, 0.2% yield column
  - benchmark: ultimate_tensile_strength
    value: 1036
    unit: MPa
    scope: material
    conditions:
      form: plate
      temperature: '-196 C (-320 F)'
      condition: heat-treated at 2150 F (1177 C), rapid cooled
      unit_in_source: 150.2 ksi
    method: Value printed in the Haynes Average Effect of Cryogenic Temperatures table
    status: ground
    source: haynes-x
    where: Average Effect of Cryogenic Temperatures table, Plate row, -311 F / -196 C line
  - benchmark: elongation
    value: 46
    unit: '%'
    scope: material
    conditions:
      form: plate
      temperature: '-196 C (-320 F)'
      condition: heat-treated at 2150 F (1177 C), rapid cooled
    method: Value printed in the Haynes Average Effect of Cryogenic Temperatures table
    status: ground
    source: haynes-x
    where: Average Effect of Cryogenic Temperatures table, Plate row, -311 F / -196 C line
  - benchmark: yield_strength
    value: 945
    unit: MPa
    scope: material
    conditions:
      form: sheet, as cold-reduced 30 percent
      temperature: room temperature
      offset: 0.2 percent
      unit_in_source: 137.0 ksi
    method: Value printed in the Haynes Cold-reduced and Welded table, As Cold-reduced, Reduced 30% row
    status: ground
    source: haynes-x
    where: Cold-reduced and Welded table, As Cold-reduced, Reduced 30% row, 0.2% yield column
  - benchmark: ultimate_tensile_strength
    value: 1110
    unit: MPa
    scope: material
    conditions:
      form: sheet, as cold-reduced 30 percent
      temperature: room temperature
      unit_in_source: 161.0 ksi
    method: Value printed in the Haynes Cold-reduced and Welded table, As Cold-reduced, Reduced 30% row
    status: ground
    source: haynes-x
    where: Cold-reduced and Welded table, As Cold-reduced, Reduced 30% row, ultimate column
  - benchmark: hardness_rockwell_b
    label: Rockwell B hardness, tungsten indenter (HRBW), plate
    value: 87
    unit: HRBW
    scope: material
    conditions:
      form: plate
      condition: solution annealed at 2150 F (1177 C)
    method: Value printed in the Haynes Room Temperature Hardness table
    status: ground
    source: haynes-x
    where: Room Temperature Hardness table, Plate row
  - benchmark: hardness_rockwell_b
    label: Rockwell B hardness, tungsten indenter (HRBW), sheet
    value: 86
    unit: HRBW
    scope: material
    conditions:
      form: sheet
      condition: solution annealed at 2150 F (1177 C)
    method: Value printed in the Haynes Room Temperature Hardness table
    status: ground
    source: haynes-x
    where: Room Temperature Hardness table, Sheet row
  - benchmark: charpy_impact_energy
    label: Charpy V-notch impact energy, average of 28 plate samples
    value: 140
    unit: J
    scope: material
    conditions:
      temperature: room temperature
      form: plate
      condition: heat-treated at 2100 F (1149 C), water quenched
      unit_in_source: 103 ft-lb
    method: Value printed in the Haynes Average Impact Strength table; the page footnote gives the sample count (28) and thickness range
    status: ground
    source: haynes-x
    where: Average Impact Strength, Plate table, RT row
  - benchmark: charpy_impact_energy
    label: Charpy V-notch impact energy, plate after 16,000 h at 1600 F
    value: 16
    unit: J
    scope: material
    conditions:
      temperature: room temperature
      form: plate
      condition: aged 16,000 h at 1600 F (871 C)
      unit_in_source: 12 ft-lb
    method: Value printed in the Haynes Aged Plate Charpy table
    status: ground
    source: haynes-x
    where: Aged Plate Charpy table, 1600 F / 871 C row, 16000 h line
corrosion:
  - environment: Flowing air at 980 C (1800 F), 1008 h, comparative static oxidation test
    headline: Alloy X loses 0.007 mm per side in 1008 h at 980 C in flowing air (Haynes).
    effect: Haynes gives metal loss of 0.29 mils (0.007 mm) per side at 1800 F and 1.5 mils (0.038 mm) per side at 2000 F. With continuous internal penetration (CIP) included, the figures are 0.74 mils (0.019 mm) and 2.7 mils (0.069 mm).
    rating: low
    conditions:
      basis: static test in flowing air, 1008 hours; the rating band is the Haynes rule for metal loss under 0.1 mm/y, which does not apply to a finite-time test
      exposure: 1008 h
    source: haynes-x
    where: Oxidation Resistance table, X row
  - environment: Combustion products of No. 2 fuel oil (0.4 percent sulfur) with 5 ppm sea salt, 900 C (1650 F), 1000 h
    headline: Hot corrosion in fuel-oil combustion gas removes 0.17 mm of metal per side in 1000 h (Haynes).
    effect: Haynes gives total metal affected per side of 6.8 mils (0.17 mm) for X, 7.5 mils (0.19 mm) for alloy 188 and 3.7 mils (0.09 mm) for alloy S after 1000 h. At 200 h, X gives 3.0 mils (0.08 mm).
    rating: moderate
    conditions:
      basis: burner-rig test, gas velocity 13 ft/s (4 m/s), thermal shock once per hour
      exposure: 200 and 1000 h
    source: haynes-x
    where: Comparative Average Hot Corrosion Resistance table, X column, 1650 F / 900 C rows
  - environment: Petrochemical service, stress-corrosion cracking
    headline: Haynes says the alloy is exceptionally resistant to stress-corrosion cracking in petrochemical applications.
    effect: The Haynes page states the resistance in general terms. It prints no cracking test result for this alloy.
    rating: low
    conditions:
      basis: qualitative statement from the product page; no test data printed
    source: haynes-x
    where: Principal Features, first paragraph
risks:
  hazards:
    - text: 'PubChem aggregated GHS for nickel metal, from 4778 company 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 47 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: Haynes refers readers to its safety data sheets for the element concentrations and health effects of a given product. 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-x
      where: Haynes product page; the SDS link is not opened in this run
  failure_risks:
    - mode: Embrittlement after long ageing at 1600 F
      trigger: Service or ageing for 16,000 h at 1600 F (871 C)
      consequence: Average Charpy V-notch energy of plate falls from 129 J after solution heat treatment to 16 J after 16,000 h at 1600 F (Haynes). Haynes also prints good ductility after prolonged exposure at 1200, 1400 and 1600 F, so the drop is in impact energy, not in tensile elongation.
      severity: high
      source: haynes-x
      where: Aged Plate Charpy table, SHT row and 1600 F / 871 C 16000 h row; Principal Features
    - mode: Loss of toughness and strength after brazing
      trigger: Brazing thin-gage sheet with a Ni-Pd-Au alloy at 1461 K (2170 F)
      consequence: NASA reports reductions of 35 percent in yield strength and elongation, 6 percent in ultimate tensile strength and 18 percent in fatigue limit compared with as-received material. The report says 200 thermal cycles between 533 K and 1144 K add a smaller further loss.
      severity: high
      source: nasa-tmx2704
      where: Abstract (summary of results item 2 gives the same brazing figures)
    - mode: Strength gain and ductility loss from cold work
      trigger: Cold reduction of 50 percent
      consequence: F&W Metals gives typical values of 1379 MPa yield strength and 3.1 percent elongation after 50 percent cold work, against 427 MPa and 38 percent in the annealed row of the same table. The table gives no form or test temperature.
      severity: moderate
      source: fwmetals-x
      where: Mechanical properties table, cold worked 50 percent and 0 percent rows
    - mode: Strength falls above about 650 C
      trigger: Service at 649 C (1200 F) or hotter
      consequence: Plate 0.2 percent yield strength falls from 340 MPa at room temperature to 212 MPa at 649 C (1200 F), and to 189 MPa at 871 C (1600 F) (Haynes).
      severity: moderate
      source: haynes-x
      where: Tensile Data, Plate table, 1200 F and 1600 F rows
  side_effects: []
  handling:
    - text: Preheat is not required. Keep the interpass temperature below 200 F (93 C). Post-weld heat treatment is not generally required (Haynes).
      source: haynes-x
      where: Preheating, Interpass Temperatures and Post-Weld Heat Treatment section
    - text: Submerged-arc welding is not recommended, because its high heat input and slow cooling can raise weld restraint and promote cracking (Haynes). Gas tungsten arc, gas metal arc and shielded metal arc welding are the processes Haynes names.
      source: haynes-x
      where: Welding section
    - text: Forge or hot-work the alloy after holding it at 2150 F (1177 C) long enough for the whole piece to reach temperature (Haynes).
      source: haynes-x
      where: Ease of Fabrication section
    - text: Anneal and rapidly cool all hot-worked or cold-worked parts to restore properties (Haynes).
      source: haynes-x
      where: Ease of Fabrication section
  mitigations:
    - text: Anneal and rapidly cool formed or hot-worked parts (Haynes).
      source: haynes-x
      where: Ease of Fabrication section; Aged Plate Charpy table
uses:
  - application: propulsion-and-tanks
    device: 'Gas turbine combustion-zone components: transition ducts, combustor cans, spray bars and flame holders, plus afterburners, tailpipes and cabin heaters (aircraft engines)'
    example: Haynes says the alloy has wide use in gas turbine engines for combustion-zone parts, and in afterburners, tailpipes and cabin heaters. Upmet lists jet engine components, afterburners and tailpipes as its industry applications. These are aircraft uses, not spacecraft uses.
    source: haynes-x
    where: Useful for Aircraft, Furnace and Chemical Process Components section; also upmet-x Industry Applications list
  - application: structures
    device: 'Industrial furnace parts: furnace rolls, retorts and muffles'
    example: Haynes says furnace rolls of this alloy were still in good condition after 8,700 hours at 2150 F (1177 C), and that the alloy resists oxidising, reducing and neutral atmospheres. Haynes also names retorts and muffles for chemical process use.
    source: haynes-x
    where: Useful for Aircraft, Furnace and Chemical Process Components section
supply:
  - subject: Nickel
    abundance: Globally, nickel resources have been estimated to contain more than 350 million tons of nickel (USGS MCS 2026)
    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: Indonesia 2,600,000 t, Philippines 270,000 t, Russia 200,000 t, Canada 140,000 t, world total 3,900,000 t. The shares are calculated by Space Mushroom from those printed values; USGS does not print shares.'
  - 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 MCS 2026)
    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 recycled from new and old scrap may be as much as 30% of the apparent supply of molybdenum.'
    substitutes:
      - 'USGS: there is little substitution for molybdenum in its major application in steels and cast irons.'
    source: usgs-mcs2026-molybdenum
    where: 'World Mine Production and Reserves table, 2025e column: China 97,000 t, Chile 42,000 t, United States 40,000 t, Peru 39,000 t, Mexico 17,000 t, world total 260,000 t. Shares calculated by Space Mushroom from those values.'
  - subject: Chromium
    abundance: World resources are greater than 12 billion tons of shipping-grade chromite (USGS MCS 2026)
    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, the leading end use, or in superalloys, the major strategic end use.'
    source: usgs-mcs2026-chromium
    where: 'World Mine Production and Reserves table, 2025e column: South Africa 23,000 t, Turkey 9,000 t, Kazakhstan 7,000 t, India 3,000 t, world total 51,000 t. Shares calculated by Space Mushroom from those values.'
  - subject: Tungsten
    abundance: World tungsten resources are geographically widespread, and China ranked first in resources and reserves (USGS MCS 2026)
    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.'
    source: usgs-mcs2026-tungsten
    where: 'World Mine Production and Reserves table, 2025 column: China 67,000 t, Vietnam 3,000 t, Kazakhstan 2,400 t, Russia 2,000 t, world total 85,000 t. Shares calculated by Space Mushroom from those values.'
documents:
  - title: HASTELLOY X alloy product page, Haynes International (UNS N06002)
    type: datasheet
    url: https://haynesintl.com/en/?p=1958
  - title: HASTELLOY X alloy, F&W Metals (chemical composition, physical and mechanical properties)
    type: datasheet
    url: https://www.fwmetals.com/materials/high-performance-alloys/hastelloy-alloy-x
  - title: Datasheet for Alloy X Nickel Sheet, Coil, Bar & Plate, United Performance Metals (2026)
    type: datasheet
    url: https://www.upmet.com/sites/default/files/datasheets/alloy-x.pdf
    year: 2026
  - title: NASA TM X-2704, Mechanical properties of Hastelloy X after brazing and thermal cycling (1973)
    type: report
    url: https://ntrs.nasa.gov/citations/19730004802
    year: 1973
  - 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 compound record for nickel (CID 935), GHS classification
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/935/JSON?heading=GHS+Classification
gaps:
  - No safety data sheet for Hastelloy X was opened. The hazards come from the PubChem nickel record, and nickel is about 47 percent of the alloy.
  - No spacecraft, rocket, satellite or cryogenic-fuel use was found in the sources read. The uses are aircraft gas turbine parts and industrial furnace parts.
  - No aqueous corrosion data (acid, chloride or seawater tests) for Hastelloy X were found on the pages read. The Ulbrich Prospector page returned a block page, and the Alloys International page lists no X data.
  - Carburisation resistance is shown in a Haynes figure only; no number was printed in the text, so it is not entered.
  - Creep rate and stress-to-rupture tables from Haynes were not entered as properties, because their names are not in the canonical property list.
  - 'NASA TM X-2704: the abstract and the summary give different figures for the thermal-cycling loss (abstract: 6 percent fatigue limit; summary: 8 percent). Only the brazing effect, which both give as 35 percent yield and elongation, is entered.'
  - The Haynes tensile tables do not restate the heat treatment in their headings. The condition is taken from the Haynes footnote (SHT, solution heat-treated, not aged) and recorded as such.
  - The F&W cold-work table gives 0 percent cold work as 427 MPa and 38 percent elongation, against 376 MPa and 46.5 percent for the Haynes sheet at room temperature. The forms and test conditions differ, so no F&W value is entered as a property.
  - Thermal conductivity differs between Haynes (9.2 W/(m K) at 25 C) and Upmet (9.1 W/(m K) at 21 C). Haynes is the entered source.
  - Electrical resistivity in F&W Metals is printed in microohm-mm, a unit that does not match the other sources, so it is not entered.
  - No cobalt supply data were read (USGS cobalt summary not fetched).
  - USGS critical-mineral list status was not checked for nickel, molybdenum, chromium or tungsten, so critical_lists is empty.
  - The solution heat-treat and hot-working temperature range below 2150 F is given only as a hold temperature. Haynes prints no hot-working window.
sources:
  haynes-x:
    title: HASTELLOY X alloy (UNS N06002, W86002), Haynes International product page
    id: Haynes International, Principal Features, Physical Properties, Tensile Data and Specifications and Codes tables
    url: https://haynesintl.com/en/?p=1958
    kind: datasheet
    license: Haynes product page (cited, not reproduced)
  fwmetals-x:
    title: HASTELLOY X alloy, F&W Metals (Fort Wayne Metals)
    id: UNS N06002, chemical composition and physical properties, mechanical properties by cold work
    url: https://www.fwmetals.com/materials/high-performance-alloys/hastelloy-alloy-x
    kind: datasheet
    license: Supplier product page (cited, not reproduced)
  upmet-x:
    title: Datasheet for Alloy X Nickel Sheet, Coil, Bar & Plate, United Performance Metals
    id: AMS 5536, AMS 5754, UNS N06002, EN 2.4665
    url: https://www.upmet.com/sites/default/files/datasheets/alloy-x.pdf
    year: 2026
    kind: datasheet
    license: Supplier datasheet, information only (cited, not reproduced)
  nasa-tmx2704:
    title: NASA TM X-2704, mechanical properties of Hastelloy X after high-temperature brazing and thermal cycling (Langley, 1973)
    id: NASA TM X-2704, NTRS 19730004802
    url: https://ntrs.nasa.gov/citations/19730004802
    year: 1973
    kind: report
    license: NASA public document (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)
license: CC-BY-4.0
updated: '2026-10-26'
review:
  status: draft
  method: assistant
  checked_values: 28
  unreachable: 1
  caveats: 6
  note: 'Values read by an AI assistant on 2026-10-26 from the pages and PDFs named in each entry. Haynes values are copied from the Haynes product page tables. The Ulbrich Prospector page returned a block page and is not used. Caveats: tensile tables do not restate the heat treatment (taken from the Haynes footnote); the NASA abstract and summary differ on the thermal-cycling loss; supply shares are calculated from USGS printed values; no safety data sheet was read; no spacecraft use was found.'
story:
  why: Hastelloy X is chosen where a nickel alloy must resist oxidation at high temperature, keep useful strength and still be formed and welded. Haynes says the alloy has an exceptional combination of oxidation resistance, fabricability and high-temperature strength. Its room-temperature density is 8.22 g/cm3, and the plate yield strength is 340 MPa in the solution heat-treated condition. The fetched sources name gas-turbine combustion parts, afterburners, tailpipes and industrial furnace parts; none names a spacecraft or rocket use.
  recipe:
    line: Hastelloy X is a wrought nickel-chromium-iron-molybdenum alloy with small tungsten and cobalt additions, and very low carbon. Haynes gives the nominal composition in weight percent, and F&W Metals gives the composition ranges. Ni is the balance.
    parts:
      - name: Nickel
        symbol: Ni
        share_percent: 47
        share_note: balance; Haynes nominal 47 wt%
        role: Matrix of the alloy. The fetched pages give no element role for nickel.
        source: haynes-x
        where: Nominal Composition table
      - name: Chromium
        symbol: Cr
        share_percent: 22
        share_note: nominal; F&W range 20.5 to 23.0 wt%
        role: Haynes names oxidation resistance as a headline property; the page does not tie it to chromium specifically.
        source: haynes-x
        where: Nominal Composition table
      - name: Iron
        symbol: Fe
        share_percent: 18
        share_note: nominal; F&W range 17.0 to 20.0 wt%
        role: Present in the nominal composition; the fetched pages give no role.
        source: haynes-x
        where: Nominal Composition table
      - name: Molybdenum
        symbol: Mo
        share_percent: 9
        share_note: nominal; F&W range 8.0 to 10.0 wt%
        role: Present in the nominal composition; the fetched pages give no role for molybdenum in this alloy.
        source: haynes-x
        where: Nominal Composition table
      - name: Cobalt
        symbol: Co
        share_percent: 1.5
        share_note: nominal; F&W range 0.5 to 2.5 wt%
        role: Present in the nominal composition; the fetched pages give no role.
        source: haynes-x
        where: Nominal Composition table
      - name: Tungsten
        symbol: W
        share_percent: 0.6
        share_note: nominal; F&W range 0.20 to 1.0 wt%
        role: Present in the nominal composition; the fetched pages give no role.
        source: haynes-x
        where: Nominal Composition table
      - name: Carbon
        symbol: C
        share_percent: 0.1
        share_note: nominal; F&W range 0.05 to 0.15 wt%
        role: Present in the nominal composition; the fetched pages give no role.
        source: haynes-x
        where: Nominal Composition table
  risk_groups:
    - title: For people
      level: 2
      verdict: Nickel record flags hazards
      lead: No safety data sheet for this alloy was opened in this run, so the hazard flags come from the PubChem nickel record. Nickel is about 47 percent of the alloy.
      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).
    - title: If it stays hot too long
      lead: These results come from the datasheets and from one NASA report, not from field incidents.
      points:
        - label: Ageing
          line: After 16,000 h at 1600 F (871 C), plate Charpy energy falls from 129 J to 16 J (Haynes).
        - label: Brazing
          line: NASA reports that brazing thin sheet with a Ni-Pd-Au alloy at 2170 F cut yield strength and elongation by 35 percent and fatigue limit by 18 percent (NASA TM X-2704).
    - title: Handling and welding
      verdict: Weld without preheat, keep the interpass below 200 F
      points:
        - label: Welding
          line: Preheat is not required, the interpass temperature should stay below 200 F (93 C), and post-weld heat treatment is not generally required (Haynes).
        - label: Forming
          line: Hold at 2150 F (1177 C) for forging or hot work, then anneal and rapidly cool (Haynes).
  uses:
    - where: Gas turbine combustion parts
      line: Haynes says the alloy has wide use in gas turbine engines for transition ducts, combustor cans, spray bars and flame holders, and in afterburners, tailpipes and cabin heaters. These are aircraft uses. No spacecraft or rocket use was found.
    - where: Industrial furnaces
      line: Furnace rolls of this alloy were still in good condition after 8,700 hours at 2150 F (1177 C) (Haynes).
  can_do:
    - label: Keep strength when hot
      value: 241 MPa yield at 649 C
      benchmark: yield_strength
      line: Sheet yield strength is 241 MPa at 649 C (1200 F) against 376 MPa at room temperature. Plate yield strength is 189 MPa at 871 C (1600 F) (Haynes).
    - label: Resist oxidation
      value: 0.007 mm per side
      line: Metal loss in flowing air is 0.007 mm per side in 1008 h at 980 C (Haynes). At 2000 F the loss is 0.038 mm per side.
    - label: Stay ductile when cold
      value: 1036 MPa at -196 C
      benchmark: ultimate_tensile_strength
      line: Plate heat-treated at 2150 F and rapidly cooled has an ultimate tensile strength of 1036 MPa and 46 percent elongation at -196 C (Haynes).
    - label: Density
      value: 8.22 g/cm3
      benchmark: density
      line: Density is 8.22 g/cm3 at 22 C (72 F), per Haynes. F&W Metals prints the same figure.
  compare: The fetched pages give no direct comparison with other grades, so the rows below show Hastelloy X values only. Read them as this grade's own figures, not as a ranking against other profiles.
  compare_rows:
    - label: Density
      benchmark: density
    - label: Thermal conductivity
      benchmark: thermal_conductivity
    - label: Thermal expansion
      benchmark: cte
  handling:
    - Preheat is not required. Keep the interpass temperature below 200 F (93 C) (Haynes).
    - Avoid submerged-arc welding, because its high heat input and slow cooling can promote cracking (Haynes).
    - Hold at 2150 F (1177 C) for hot forging or hot work, then anneal and rapidly cool (Haynes).
    - Keep the alloy out of long ageing at 1600 F (871 C) where impact energy matters, since Charpy energy drops from 129 J to 16 J after 16,000 h (Haynes).
  good_for:
    - Hot oxidising gas and furnace service, where the alloy must also be formed and welded (Haynes).
    - Gas-turbine combustion-zone parts and afterburner or tailpipe parts in aircraft engines (Haynes; Upmet).
    - Industrial furnace rolls and parts, with 8,700 hours of service at 2150 F reported in good condition (Haynes).
  watch_out:
    - Long ageing at 1600 F drops plate Charpy energy from 129 J to 16 J (Haynes).
    - Brazing sheet at 2170 F reduces yield strength and elongation by 35 percent (NASA TM X-2704).
    - 'Cold work raises yield strength strongly and cuts elongation: typical values are 1379 MPa and 3.1 percent after 50 percent cold work (F&W Metals).'
    - No aqueous corrosion or spacecraft data were found for this alloy in this run.
  verdict: Hastelloy X is an oxidation-resistant nickel alloy for hot combustion and furnace parts, with 340 MPa plate yield strength at room temperature and 8.22 g/cm3 density (Haynes). It keeps useful strength and formability at high temperature, but long ageing at 1600 F and brazing both cut toughness sharply. No spacecraft, rocket or satellite use was found, and no safety data sheet or aqueous corrosion data were read in this run.