Nimonic 90 UNS N07090 (W. Nr. 2.4632)

spore: profile
id: nimonic-90
spore_version: 0.2
family: nickel-alloys
name: Nimonic 90
abbreviation: UNS N07090 (W. Nr. 2.4632)
role: age-hardened creep-resisting superalloy
category: metals
type: nickel-superalloys
summary: |
  Nimonic 90 is a wrought, age-hardened nickel-chromium-cobalt superalloy with titanium and aluminium additions, designed for creep-resistant service up to 920 °C. In the Special Metals datasheet, extruded bar in its heat-treated condition has a 0.2 % proof stress of 752 MPa and a tensile strength of 1175 MPa at 20 °C, and still 532 MPa proof stress at 800 °C. It is used for turbine blades, discs, forgings and ring sections. Its density is 8.18 g/cm3, and it oxidises at 10.40 mg/cm2 per 100 h at 1000 °C. No spacecraft, rocket or satellite use was found in the sources read.
best_for: High-temperature strength and creep resistance up to about 920 °C, for turbine blades, discs, forgings and ring sections
weakest_at: Weight (8.18 g/cm3), hard machining (250 to 350 HV when fully heat treated), and oxide spalling under cyclic heating (onset after 250 h at 990 °C)
identity:
  formula: Nickel-chromium-cobalt superalloy, balance Ni, with Cr 18.0 to 21.0, Co 15.0 to 21.0, Ti 2.0 to 3.0, Al 1.0 to 2.0, Fe 1.5 max, Mn 1.0 max, Si 1.0 max, C 0.13 max (wt %, Special Metals datasheet)
  source: sm90
  where: Composition table, Special Metals publication SMC-080; the same limits are printed in the Fort Wayne Metals table for AMS 5829 and UNS N07090
  designations:
    - system: UNS
      code: N07090
      source: sm90
      where: Title line, NIMONIC alloy 90 (UNS N07090/W. Nr. 2.4632)
    - system: EN
      code: '2.4632'
      source: sm90
      where: Title line and Available Products and Specifications, Werkstoff Number 2.4632
    - system: AMS
      code: '5829'
      source: fw-nimonic90
      where: Chemical composition table, column heading AMS 5829 and UNS N07090
    - system: BS
      code: HR2
      note: bar, billet and forging stock
      source: sm90
      where: Available Products and Specifications, Rod, Bar, Wire and Forging Stock
    - system: Trade name
      code: Nimonic 90
      source: acm90
      where: Page title, Nickel Alloy 90 / Nimonic 90 (UNS N07090)
tags:
  environments: []
  stresses:
    - high-temperature-creep
    - oxidation-and-sulphur-dioxide
  applications:
    - propulsion-and-tanks
    - mechanisms
    - structures
properties:
  - benchmark: density
    label: Density, extruded bar
    value: 8.18
    unit: g/cm3
    scope: material
    conditions:
      form: extruded bar, heat treated 8 h at 1080 °C AC + 16 h at 700 °C AC
      temperature: not stated
      unit_in_source: Mg/m3 (0.296 lb/in3)
    method: Value printed in a manufacturer datasheet, determined on the stated heat-treated material
    status: ground
    source: sm90
    where: Physical Properties, row Density
  - benchmark: melting_point
    label: Liquidus temperature
    value: 1370
    unit: °C
    scope: material
    conditions:
      unit_in_source: 2500 °F
    method: Printed in a manufacturer datasheet
    status: ground
    source: sm90
    where: Physical Properties, Melting Range, Liquidus temperature
  - benchmark: melting_point
    label: Solidus temperature
    value: 1310
    unit: °C
    scope: material
    conditions:
      unit_in_source: 2390 °F
    method: Printed in a manufacturer datasheet
    status: ground
    source: sm90
    where: Physical Properties, Melting Range, Solidus temperature
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 20 °C
    value: 11.47
    unit: W/(m·K)
    scope: material
    conditions:
      temperature: 20 °C
      unit_in_source: W/m·°C (80.46 Btu·in/ft2·h·°F)
    method: Value in a manufacturer datasheet; the table footnote says it is calculated from electrical resistance measurements
    status: ground
    source: sm90
    where: Table 2 Thermal Conductivity, row 20 °C
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 1000 °C
    value: 27.88
    unit: W/(m·K)
    scope: material
    conditions:
      temperature: 1000 °C
      unit_in_source: W/m·°C (195.58 Btu·in/ft2·h·°F)
    method: Value in a manufacturer datasheet; the table footnote says it is calculated from electrical resistance measurements
    status: ground
    source: sm90
    where: Table 2 Thermal Conductivity, row 1000 °C
  - benchmark: specific_heat
    label: Specific heat at 20 °C
    value: 446
    unit: J/(kg·K)
    scope: material
    conditions:
      temperature: 20 °C
      unit_in_source: J/kg·°C (0.11 Btu/lb·°F)
    method: Value in a manufacturer datasheet
    status: ground
    source: sm90
    where: Table 1 Specific Heat, row 20 °C
  - benchmark: electrical_resistivity
    label: Electrical resistivity at 20 °C
    value: 1.18
    unit: µΩ·m
    scope: material
    conditions:
      temperature: 20 °C
      unit_in_source: µohm·m (710 ohm·circ·mil/ft)
    method: Value in a manufacturer datasheet
    status: ground
    source: sm90
    where: Table 4 Electrical Properties, line Electrical Resistivity at 20°C
  - benchmark: cte
    label: Mean coefficient of linear thermal expansion, 20 to 100 °C
    value: 12.7
    unit: µm/(m·K)
    scope: material
    conditions:
      temperature_range: 20 to 100 °C
      unit_in_source: µm/m °C (7.1 in/in °F x 10-6)
    method: Mean value in a manufacturer datasheet
    status: ground
    source: sm90
    where: Table 3 Mean Coefficient of Linear Thermal Expansion, row 20-100 °C
  - benchmark: cte
    label: Mean coefficient of linear thermal expansion, 20 to 800 °C
    value: 16.2
    unit: µm/(m·K)
    scope: material
    conditions:
      temperature_range: 20 to 800 °C
      unit_in_source: µm/m °C (9.0 in/in °F x 10-6)
    method: Mean value in a manufacturer datasheet
    status: ground
    source: sm90
    where: Table 3 Mean Coefficient of Linear Thermal Expansion, row 20-800 °C
  - benchmark: elastic_modulus
    label: Dynamic Young's modulus, extruded bar, 20 °C
    value: 204
    unit: GPa
    scope: material
    conditions:
      temperature: 20 °C
      form: extruded bar (8 casts), heat treated 8 h at 1080 °C AC + 16 h at 700 °C AC
      unit_in_source: GPa (30 x 10^3 ksi)
    method: Dynamic modulus printed in a manufacturer datasheet
    status: ground
    source: sm90
    where: Table 6 Dynamic Young's Modulus of Extruded Bar, column Extruded Bar 1, row 20 °C
  - benchmark: yield_strength
    label: 0.2 % proof stress, extruded bar, 20 °C
    value: 752
    unit: MPa
    scope: material
    conditions:
      temperature: 20 °C
      form: extruded bar, heat treated 8 h at 1080 °C AC + 16 h at 700 °C AC
      measure: 0.2 % proof stress
      unit_in_source: 109 ksi
      basis: average of 9 casts
    method: Average result printed in a manufacturer datasheet; strain rate 0.005/min to proof stress at room temperature
    status: ground
    source: sm90
    where: Table 8 Tensile Properties of Extruded Bar, row 20 °C, column 0.2% Proof Stress
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, extruded bar, 20 °C
    value: 1175
    unit: MPa
    scope: material
    conditions:
      temperature: 20 °C
      form: extruded bar, heat treated 8 h at 1080 °C AC + 16 h at 700 °C AC
      unit_in_source: 170 ksi
      basis: average of 9 casts
    method: Average result printed in a manufacturer datasheet
    status: ground
    source: sm90
    where: Table 8 Tensile Properties of Extruded Bar, row 20 °C, column Tensile Strength
  - benchmark: elongation
    label: Elongation, extruded bar, 20 °C
    value: 30
    unit: '%'
    scope: material
    conditions:
      temperature: 20 °C
      form: extruded bar, heat treated 8 h at 1080 °C AC + 16 h at 700 °C AC
      gauge_length: 5.65 √So
    method: Average result printed in a manufacturer datasheet
    status: ground
    source: sm90
    where: Table 8 Tensile Properties of Extruded Bar, row 20 °C, column Elongation on 5.65 √So
  - benchmark: yield_strength
    label: 0.2 % proof stress, extruded bar, 800 °C
    value: 532
    unit: MPa
    scope: material
    conditions:
      temperature: 800 °C
      form: extruded bar, heat treated 8 h at 1080 °C AC + 16 h at 700 °C AC
      measure: 0.2 % proof stress
      unit_in_source: 77 ksi
    method: Average result printed in a manufacturer datasheet; strain rate 0.002/min to proof stress at elevated temperature
    status: ground
    source: sm90
    where: Table 8 Tensile Properties of Extruded Bar, row 800 °C, column 0.2% Proof Stress
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, extruded bar, 800 °C
    value: 657
    unit: MPa
    scope: material
    conditions:
      temperature: 800 °C
      form: extruded bar, heat treated 8 h at 1080 °C AC + 16 h at 700 °C AC
      unit_in_source: 95 ksi
    method: Average result printed in a manufacturer datasheet
    status: ground
    source: sm90
    where: Table 8 Tensile Properties of Extruded Bar, row 800 °C, column Tensile Strength
  - benchmark: creep_rupture_stress_1000h
    label: Stress to produce rupture in 1000 h at 750 °C, extruded bar subsequently forged
    value: 275
    unit: MPa
    scope: material
    conditions:
      temperature: 750 °C (1382 °F)
      time: 1000 h
      form: extruded bar, subsequently forged, heat treated 8 h at 1080 °C AC + 16 h at 700 °C AC
      unit_in_source: 40 ksi
      basis: average of 15 casts, Graham and Walles analysis
    method: Average result printed in a manufacturer datasheet; the datasheet says these are typical values
    status: ground
    note: Benchmark creep_rupture_stress_1000h is not in the property canon; see gaps.
    source: sm90
    where: Table 13 Creep Rupture Properties of Extruded Bar Subsequently Forged, row 750 °C, GW line, column 1000 h
  - benchmark: oxidation_weight_loss_100h
    label: Descaled weight loss after 100 h in air, 800 °C
    value: 0.46
    unit: mg/cm2
    scope: material
    conditions:
      temperature: 800 °C
      time: 100 h
      exposure: continuous heating in air, descaled specimen
    method: Value printed in a manufacturer datasheet
    status: ground
    note: Benchmark oxidation_weight_loss_100h is not in the property canon; see gaps.
    source: sm90
    where: Corrosion Resistance, Oxidation in Air (continuous heating), column 800 °C
  - benchmark: oxidation_weight_loss_100h
    label: Descaled weight loss after 100 h in air, 1000 °C
    value: 10.4
    unit: mg/cm2
    scope: material
    conditions:
      temperature: 1000 °C
      time: 100 h
      exposure: continuous heating in air, descaled specimen
    method: Value printed in a manufacturer datasheet
    status: ground
    note: Benchmark oxidation_weight_loss_100h is not in the property canon; see gaps.
    source: sm90
    where: Corrosion Resistance, Oxidation in Air (continuous heating), column 1000 °C
  - benchmark: hardness_hv
    label: Hardness, fully heat-treated condition
    value: 250
    value_high: 350
    bound: range
    unit: HV
    scope: material
    conditions:
      condition: fully heat-treated, the condition used for machining
      unit_in_source: HV
    method: Range printed in a manufacturer datasheet in the machining note
    status: ground
    note: Benchmark hardness_hv is not in the property canon; see gaps.
    source: sm90
    where: Machining section, high material hardness in this condition, 250-350 HV
  - benchmark: yield_strength
    label: 0.2 % proof stress, cold-formed sheet, annealed
    value: 461
    unit: MPa
    scope: material
    conditions:
      form: sheet 0.6 to 2.0 mm, annealed 2 to 3 min at 1150 °C FBQ
      measure: 0.2 % proof stress
      unit_in_source: 67 ksi
    method: Average value printed in a manufacturer datasheet for cold forming operations
    status: ground
    source: sm90
    where: Cold Working section, row 0.2% proof stress
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, cold-formed sheet, annealed
    value: 865
    unit: MPa
    scope: material
    conditions:
      form: sheet 0.6 to 2.0 mm, annealed 2 to 3 min at 1150 °C FBQ
      unit_in_source: 125 ksi
    method: Average value printed in a manufacturer datasheet for cold forming operations
    status: ground
    source: sm90
    where: Cold Working section, row Tensile strength
corrosion:
  - environment: Air, continuous heating
    headline: Descaled weight loss in air rises from 0.46 mg/cm2 at 800 °C to 10.40 mg/cm2 at 1000 °C in 100 h.
    effect: 'Weight loss after 100 h of continuous heating: 0.46 at 800 °C, 2.52 at 900 °C, 5.50 at 950 °C, 10.40 at 1000 °C and 11.23 mg/cm2 at 1100 °C.'
    rating: moderate
    conditions:
      exposure: 100 h continuous heating in air
      specimen: descaled
    source: sm90
    where: Corrosion Resistance table, Oxidation in Air (continuous heating)
  - environment: Air, cyclic heating (15 min in furnace, 5 min outside)
    headline: Scale spalls after 250 h at 990 °C and after 75 h at 1110 °C, while 890 °C and 910 °C show no spalling within 1000 h.
    effect: 'Time to onset of spalling: more than 1000 h at 890 and 910 °C (weight gains of 2.95 and 5.52 mg/cm2 in 1000 h), 250 h at 990 °C (rate 0.304 mg/cm2/h, weight change -214 mg/cm2 in 1000 h), 100 h at 1090 °C and 75 h at 1110 °C (rate 1.268 mg/cm2/h, weight change -1107 mg/cm2 in 1000 h).'
    rating: moderate
    conditions:
      cycle: 15 min in furnace, 5 min outside
      time: up to 1000 h
    source: sm90
    where: Corrosion Resistance table, Cyclic Heating (15 min in furnace, 5 min outside)
  - environment: Sulphur dioxide atmospheres, 3 % SO2
    headline: Weight loss in 3 % SO2 is largest at 700 °C in air (8.1 mg/cm2) and at 800 °C in argon (40.0 mg/cm2), after 1000 h.
    effect: 'After 1000 h: in 3 % SO2 in air, 4.5 mg/cm2 at 600 °C, 8.1 at 700 °C, 1.4 at 800 °C and 2.0 at 900 °C; in 3 % SO2 in argon, 3.7 at 600 °C, 18.0 at 700 °C and 40.0 at 800 °C.'
    rating: moderate
    conditions:
      exposure: 1000 h
      specimen: descaled
    source: sm90
    where: Corrosion Resistance table, Resistance to Atmospheres Containing SO2
risks:
  hazards:
    - text: 'PubChem record for nickel (CID 935), aggregated from ECHA C&L notifications, Signal word Danger. Nickel is the largest element in this alloy, so these codes describe the constituent. Codes with share of notifications: H317 (99.9 %) may cause an allergic skin reaction; H351 (72.9 %) suspected of causing cancer; H350 (22.5 %) may cause cancer; H372 (99.7 %) causes damage to organs through prolonged or repeated exposure; H334 (10.3 %) may cause allergy or asthma symptoms if inhaled; H341 (13.5 %) suspected of causing genetic defects; H360F (18 %) may damage fertility; H412 (47.2 %) harmful to aquatic life with long lasting effects.'
      ghs:
        - H317
        - H334
        - H341
        - H350
        - H351
        - H360F
        - H372
        - H412
      source: pubchem-ni
      where: GHS Classification section, aggregated ECHA C&L notifications for nickel (CID 935)
    - text: No safety data sheet for Nimonic 90 itself was read in this run. Cobalt (15.0 to 21.0 %) is also a major constituent and its hazard codes were not read.
      ghs: []
      source: sm90
      where: Composition table (constituents named)
  failure_risks:
    - mode: Creep rupture under long load at 750 °C
      trigger: Sustained stress at 750 °C for 1000 h or longer
      consequence: The average stress to rupture in 1000 h at 750 °C is 275 MPa for extruded bar subsequently forged. The same table gives 1000 h values at 700, 815 and 870 °C, which were not entered (see gaps).
      severity: moderate
      source: sm90
      where: Table 13, row 750 °C, GW line
    - mode: Loss of proof strength at high temperature
      trigger: Service at 800 °C and above in the heat-treated condition
      consequence: 0.2 % proof stress of extruded bar falls from 752 MPa at 20 °C to 532 MPa at 800 °C and 306 MPa at 900 °C.
      severity: moderate
      source: sm90
      where: Table 8, rows 20 °C, 800 °C and 900 °C, column 0.2% Proof Stress
    - mode: Oxide scale spalling under cyclic heating
      trigger: Repeated heating and cooling in air at 990 °C or above
      consequence: Scale spalls after 250 h at 990 °C and after 75 h at 1110 °C in the datasheet cyclic test, with weight loss of 214 to 1107 mg/cm2 in 1000 h.
      severity: moderate
      source: sm90
      where: Corrosion Resistance table, Cyclic Heating
    - mode: Microfissuring in fusion welds above about 5 mm
      trigger: Fusion welding (TIG or MIG) of sections thicker than about 5 mm
      consequence: The datasheet says microfissuring may occur in both the weld and the heat-affected zone.
      severity: moderate
      source: sm90
      where: Welding section
  side_effects:
    - text: Density is 8.18 g/cm3, so the weight of parts is high for the strength they carry in the heat-treated state.
      affects: Mass of turbine parts and rotating components
      source: sm90
      where: Physical Properties, row Density
  handling:
    - text: Machine only in the fully heat-treated condition, where hardness is 250 to 350 HV and stringent machining is needed.
      source: sm90
      where: Machining section
    - text: Hot work in the range 1050 to 1200 °C. Interstage anneal sheet at 1040 °C, then water quench or air cool.
      source: sm90
      where: Working Instructions, Hot Working and Annealing
    - text: Weld solution-treated material only, and give post-weld heat treatment to recover properties.
      source: sm90
      where: Welding section
  mitigations: []
uses:
  - application: propulsion-and-tanks
    device: Gas turbine blades and discs
    example: The datasheet lists turbine blades and discs as uses. Wikipedia says Nimonic 90 was used on the Bristol Proteus aviation gas turbine, and Smiths lists gas turbine blades as its traditional use.
    source: sm90
    where: Opening paragraph (turbine blades, discs); see also wiki-nimonic (Uses) and smiths-nimonic90 (Applications)
  - application: mechanisms
    device: High-temperature springs
    example: Aircraft Materials lists high-temperature springs among the typical applications, and BS HR501 cold-drawn wire is specified for springs. Smiths also lists high temperature springs.
    source: acm90
    where: Description paragraph and Specifications list (BS HR501)
  - application: structures
    device: Forgings and ring sections
    example: The datasheet lists forgings and ring sections as uses, and gives forging stock and extruded section as standard product forms.
    source: sm90
    where: Opening paragraph and Available Products and Specifications
  - application: propulsion-and-tanks
    device: High performance engine valves and turbocharger parts
    example: Smiths lists engine components, high performance engine valves and turbocharger applications, and says the alloy is popular in motorsport and automotive.
    source: smiths-nimonic90
    where: Applications line on the product page
supply:
  - subject: Nickel (mine production, 2025 estimate)
    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: New Caledonia
        share_percent: 3.6
        year: 2025
      - country: Canada
        share_percent: 3.6
        year: 2025
    critical_lists: []
    recycling: 'USGS: nickel recovered from scrap was about 60 % of apparent U.S. consumption in 2025, and most recycled nickel went into new alloys and stainless steel. Stainless and alloy steel plus nickel-containing alloys were more than 85 % of U.S. consumption.'
    substitutes:
      - 'USGS: low-nickel, duplex or ultrahigh-chromium stainless steels substitute for austenitic grades; titanium alloys can substitute for nickel or nickel-base alloys in corrosive environments.'
    source: usgs-ni
    where: World Mine Production and Reserves table, 2025e column (world total 3,900,000 t rounded; shares calculated by Space Mushroom from Indonesia 2,600,000, Philippines 270,000, Russia 200,000, New Caledonia 140,000 and Canada 140,000 t); Domestic Production and Use; Recycling; Substitutes
  - subject: Cobalt (about 15 to 21 % of the alloy, mine production)
    producers:
      - country: Congo (Kinshasa)
        share_percent: 73
        year: 2025
      - country: Indonesia
        share_percent: 14
        year: 2025
    critical_lists: []
    recycling: 'USGS: in 2025 the cobalt content of purchased scrap was 25 % of estimated U.S. cobalt consumption; secondary cobalt was 2,000 tons.'
    substitutes:
      - 'USGS: depending on application, substitution for cobalt could lose product performance; nickel-base alloys or ceramics are cited as substitutes in jet engines.'
    source: usgs-co
    where: Events, Trends, and Issues (Congo (Kinshasa) 73 % and Indonesia 14 % of world mined cobalt); Domestic Production and Use (51 % of U.S. cobalt in superalloys, mainly aircraft gas turbine engines); Substitutes
documents:
  - title: Special Metals technical bulletin NIMONIC alloy 90, publication SMC-080 (2004)
    type: datasheet
    url: https://www.specialmetals.com/documents/technical-bulletins/nimonic-alloy-90.pdf
    year: 2004
  - title: Fort Wayne Metals, Nimonic alloy 90 product page (composition and physical properties)
    type: datasheet
    url: https://fwmetals.com/what-we-do/materials/high-performance-alloys/nimonic-alloy-90
  - title: Smiths High Performance, Nimonic 90 product page (applications)
    type: datasheet
    url: https://www.smithshp.com/nimonic-90.htm
  - title: Aircraft Materials, Nickel Alloy 90 / Nimonic 90 (UNS N07090)
    type: datasheet
    url: https://aircraftmaterials.com/data/nickel/nimonic90.html
  - title: 'Wikipedia: Nimonic (history, Bristol Proteus use)'
    type: database
    url: https://en.wikipedia.org/wiki/Nimonic
  - 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: Cobalt'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-cobalt.pdf
    year: 2026
  - title: PubChem compound record for nickel (CID 935), GHS classification (ECHA C&L Inventory)
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/935/JSON?heading=GHS+Classification
gaps:
  - No spacecraft, rocket, satellite or launch-vehicle use of Nimonic 90 was found in the pages read. The search results gave gas turbine, jet engine, motorsport and automotive uses only, and the Goodfellow page's 'Space Technology' label is a generic marketing category, so it was not used. The uses section therefore has no space entry.
  - No space-environment data (outgassing, atomic oxygen, radiation, thermal cycling in vacuum) were looked up for Nimonic 90.
  - The safety data sheet for Nimonic 90 itself was not read. The hazard codes come from the PubChem nickel record, which describes the nickel constituent, not the alloy. Cobalt hazard codes were not read.
  - Benchmarks creep_rupture_stress_1000h, oxidation_weight_loss_100h and hardness_hv are not in spores/property-canon.yaml and are used as short snake_case names. The canon file should be checked before import.
  - Only one 1000 h creep rupture value (750 °C, Graham and Walles) is recorded. The 815 °C, 870 °C and 700 °C rows and the sheet creep table (Table 14) were read but not entered, to keep one form and one method per row.
  - Atmospheric and seawater corrosion, stress-corrosion cracking and hydrogen effects were not found in the pages read.
  - Electrical resistivity from the Fort Wayne Metals page (118 µohm·cm, 22 °C) was not entered, because the Special Metals value (1.18 µohm·m at 20 °C) is the one from the datasheet.
  - 'The Fort Wayne Metals cold-worked table (0 %, 15 %, 60 %, 80 % cold work) was not used: the page text does not separate the columns cleanly, and the annealing condition for the 0 % row is not stated.'
  - The Alloys International page gives an iron content of 58.5 % in its chemistry table, which is a mislabelled nickel figure. It was not used, and its melting point and density figures were not entered because they were not read from its table in this run.
  - No ASTM, DIN or EN name (for example X-series or 1.xxxx material name) for Nimonic 90 was printed in a page read in this run, so only the designations listed above are recorded. ASTM B637 and B463 were named in search snippets but not read on a fetched page.
  - Modulus of elasticity in tension (not dynamic) and the room-temperature hardness of extruded bar were not found. The sheet hardness of 243 HV in the datasheet was not entered because its condition is annealed sheet, not the bar condition used for the other values.
  - Grain size, microstructure (gamma-prime volume) and the effect of cold work on creep were not read.
  - USGS critical-mineral list membership for nickel and cobalt was not confirmed in the chapter text read, so critical_lists is empty for both. The nickel chapter cites Executive Order 14285 and nickel as an example of critical minerals in its text, which is recorded only as context.
  - Cobalt and nickel supply shares are 2025 estimates from USGS. The nickel country shares are calculated from printed tonnages; the cobalt shares are printed in the text.
sources:
  sm90:
    title: NIMONIC alloy 90 (UNS N07090/W. Nr. 2.4632), Special Metals technical bulletin SMC-080
    id: Special Metals publication SMC-080, copyright 2004
    url: https://www.specialmetals.com/documents/technical-bulletins/nimonic-alloy-90.pdf
    year: 2004
    kind: datasheet
    license: Manufacturer technical bulletin (cited, not reproduced)
  fw-nimonic90:
    title: Nimonic alloy 90, Fort Wayne Metals product page (chemical composition and physical properties)
    id: AMS 5829, UNS N07090
    url: https://fwmetals.com/what-we-do/materials/high-performance-alloys/nimonic-alloy-90
    kind: datasheet
    license: Supplier web page (cited, not reproduced)
  smiths-nimonic90:
    title: Nimonic 90, Smiths High Performance product page (applications)
    url: https://www.smithshp.com/nimonic-90.htm
    kind: web
    license: Supplier web page (cited, not reproduced)
  acm90:
    title: Nickel Alloy 90 / Nimonic 90 (UNS N07090), Aircraft Materials
    id: UNS N07090, Werkstoff Nr. 2.4632, AMS 5829, BS HR2, HR501
    url: https://aircraftmaterials.com/data/nickel/nimonic90.html
    kind: web
    license: Supplier web page (cited, not reproduced)
  wiki-nimonic:
    title: 'Nimonic (Wikipedia): history, Wiggin Works and Bristol Proteus use'
    url: https://en.wikipedia.org/wiki/Nimonic
    kind: web
    license: CC BY-SA 4.0 (cited, not reproduced)
  usgs-ni:
    title: Mineral Commodity Summaries 2026, Nickel
    id: USGS MCS 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  usgs-co:
    title: Mineral Commodity Summaries 2026, Cobalt
    id: USGS MCS 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-cobalt.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  pubchem-ni:
    title: PubChem compound record for nickel (CID 935), GHS classification from ECHA C&L Inventory
    id: CID 935, CAS 7440-02-0
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/935/JSON?heading=GHS+Classification
    kind: database
    license: PubChem (NCBI), public domain; ECHA data as attributed by PubChem
license: CC-BY-4.0
updated: '2026-10-26'
review:
  status: draft
  method: assistant
  checked_values: 21
  unreachable: 0
  caveats: 6
  note: Values were read by an AI assistant on 2026-10-26 from the pages and PDFs named in each entry. The datasheet values are typical values from one manufacturer's bulletin (2004). Strength rows are averages of named casts and forms, not minimum specifications. The creep, oxidation and hardness rows use snake_case benchmarks outside the canon. The hazard codes describe nickel, not the alloy. No space use was found.
story:
  risk_groups:
    - title: For people
      lead: The hazard codes in the sources describe nickel, the largest constituent. No safety data sheet for the alloy itself was read.
      level: 1
      verdict: Nickel codes apply
      points:
        - label: Nickel as a constituent
          line: PubChem's aggregated record for nickel lists H317 (allergic skin reaction, 99.9 % of notifications), H351 (suspected cancer, 72.9 %) and H372 (organ damage with prolonged exposure, 99.7 %). The signal word is Danger.
        - label: Cobalt as a constituent
          line: Cobalt makes up 15 to 21 % of the alloy. Its hazard codes were not read in this run.
    - title: If it fails
      lead: These failure routes come from the datasheet tests and the welding notes. None of them is a space result.
      points:
        - label: Creep at 750 °C
          line: The 1000 h rupture stress at 750 °C is 275 MPa for extruded bar subsequently forged.
        - label: Softening at 800 °C and above
          line: 0.2 % proof stress falls from 752 MPa at 20 °C to 532 MPa at 800 °C and 306 MPa at 900 °C.
        - label: Scale spalling
          line: In a cyclic heating test, scale spalls after 250 h at 990 °C and after 75 h at 1110 °C.
    - title: Handling and storage
      points:
        - label: Machine it soft or hard on purpose
          line: Machine only in the fully heat-treated condition, where hardness is 250 to 350 HV.
        - label: Weld with care
          line: Fusion welds above about 5 mm can microfissure. Weld solution-treated material and give post-weld heat treatment.
  why: Nimonic 90 was built to keep strength at high temperature. The Special Metals bulletin describes it as a wrought, age-hardened nickel-chromium-cobalt alloy with titanium and aluminium additions, for creep-resisting service up to 920 °C. Wikipedia says the Nimonic family was first developed at Wiggin Works in Hereford, England, to support the Whittle jet engine. Its density is 8.18 g/cm3, and in the heat-treated bar it still has a 0.2 % proof stress of 532 MPa at 800 °C.
  uses:
    - where: Gas turbine parts
      line: The datasheet lists turbine blades and discs. Wikipedia says Nimonic 90 was used on the Bristol Proteus aviation gas turbine.
    - where: Springs and engine parts
      line: Aircraft Materials lists high-temperature springs. Smiths lists high performance engine valves and turbocharger parts.
    - where: Forgings and rings
      line: The datasheet lists forgings and ring sections, supplied as forging stock and extruded section.
  can_do:
    - label: Stay strong when hot
      value: 532 MPa at 800 °C
      benchmark: yield_strength
      line: The 0.2 % proof stress of heat-treated extruded bar is 752 MPa at 20 °C and 532 MPa at 800 °C.
    - label: Carry long loads at 750 °C
      value: 275 MPa for 1000 h
      benchmark: creep_rupture_stress_1000h
      line: The average stress to rupture in 1000 h at 750 °C is 275 MPa for extruded bar subsequently forged.
    - label: Weight
      value: 8.18 g/cm3
      benchmark: density
      line: Density is 8.18 g/cm3 in the datasheet and in the Fort Wayne Metals page.
    - label: Melting
      value: 1310 to 1370 °C
      benchmark: melting_point
      line: The solidus is 1310 °C and the liquidus is 1370 °C in the datasheet.
    - label: Thermal expansion
      value: 12.7 µm/(m·K)
      benchmark: cte
      line: The mean coefficient of linear expansion from 20 to 100 °C is 12.7 µm/(m·K), rising to 16.2 µm/(m·K) for 20 to 800 °C.
  compare: Compared with the other nickel superalloys on this site, Nimonic 90 is a wrought alloy rated to about 920 °C, with the datasheet giving proof and creep values from one manufacturer's bulletin. Read the rows below as examples of the same measures, not as a ranking, because the heat treatments and test methods differ between alloys.
  compare_rows:
    - label: Density
      benchmark: density
    - label: Thermal conductivity
      benchmark: thermal_conductivity
    - label: Thermal expansion
      benchmark: cte
  handling:
    - 'Specify the heat treatment: 8 h at 1080 °C air cool plus 16 h at 700 °C air cool for bar.'
    - Machine only in the fully heat-treated condition, expecting 250 to 350 HV.
    - Hot work in the range 1050 to 1200 °C.
    - Weld solution-treated material and give post-weld heat treatment.
  good_for:
    - 'High-temperature parts: 532 MPa proof stress at 800 °C in heat-treated extruded bar.'
    - 'Long-term load at 750 °C: 275 MPa for 1000 h, average of 15 casts.'
    - Gas turbine blades, discs, forgings and springs, as listed in the sources.
  watch_out:
    - 'Weight: 8.18 g/cm3, high for a thermal-structural part.'
    - Scale spalls after 250 h at 990 °C under cyclic heating in the datasheet test.
    - Fusion welds thicker than about 5 mm can microfissure.
    - No spacecraft, rocket or satellite use was found in the sources, so this profile makes no space claim.
  verdict: Nimonic 90 is a heat-treated wrought superalloy for turbine and forged parts up to about 920 °C, with 752 MPa proof stress at 20 °C and 532 MPa at 800 °C in the datasheet. It is heavy, hard to machine in its heat-treated state, and creep-limited at 750 °C over long times. The sources read contain no space use, outgassing or radiation data for it.
  recipe:
    line: Wrought nickel-chromium-cobalt alloy, age-hardened with titanium and aluminium. Bar is heat treated at 1080 °C for 8 h, air cooled, then at 700 °C for 16 h, air cooled (Special Metals). Composition in weight percent, AMS 5829 and UNS N07090 limits (Special Metals and Fort Wayne Metals).
    parts:
      - name: Nickel
        symbol: Ni
        share: balance
        role: Matrix, face-centred cubic austenite that the age-hardening phases strengthen.
      - name: Chromium
        symbol: Cr
        share: 18.0 to 21.0 wt %
        role: Oxidation and corrosion resistance through the chromia scale.
      - name: Cobalt
        symbol: Co
        share: 15.0 to 21.0 wt %
        role: Solid-solution strengthening and high-temperature stability.
      - name: Titanium
        symbol: Ti
        share: 2.0 to 3.0 wt %
        role: Age-hardening addition with aluminium, forming gamma-prime precipitates.
      - name: Aluminium
        symbol: Al
        share: 1.0 to 2.0 wt %
        role: Age-hardening addition with titanium, forming gamma-prime precipitates.
      - name: Iron, manganese, silicon, carbon, copper and others
        symbol: Fe, Mn, Si, C, Cu
        share: Fe 1.5 max, Mn 1.0 max, Si 1.0 max, C 0.13 max, Cu 0.2 max
        role: Impurity and trace limits in the specification; carbon is limited as printed in the composition table.