spore: profile
id: nichrome
spore_version: 0.2
family: resistance-and-thermocouple-alloys
name: Nichrome
abbreviation: NiCr 80/20
role: resistance heating alloy
category: metals
type: nickel-superalloys
summary: |
  Nichrome is the nickel-chromium resistance alloy with about 80 % nickel and 20 % chromium, sold as NiCr 80/20 (UNS N06003, material 2.4869). Its electrical resistivity is 1.09 Ohm mm2/m at 20 °C, its melting point is about 1400 °C, and Kanthal gives a maximum continuous operating temperature in air of 1200 °C. It is soft and ductile at room temperature in fine wire (810 MPa tensile strength and 30 % elongation for 1.0 mm wire), but its strength falls quickly with temperature: 15 MPa gives 1 % creep in 1000 h at 800 °C.
best_for: 'Carrying current as a heater: 1.09 Ohm mm2/m resistivity with a continuous limit of 1200 °C in air, and a chromium oxide scale that resists oxidation'
weakest_at: 'Strength at temperature: 15 MPa for 1 % creep in 1000 h at 800 °C and 4 MPa at 1000 °C, and a thermal conductivity of only 15 W/(m·K)'
identity:
  formula: 'Nickel-chromium alloy, about 80 % Ni and 20 % Cr by mass; Kanthal Nikrothal 80 composition: Ni balance, Cr 19.0 to 21.0 %, Si 1.0 to 1.7 %, Mn up to 1.0 %, C up to 0.10 %'
  source: kanthal-nikrothal80
  where: Chemical composition table of the Kanthal Nikrothal 80 wire datasheet (Ni Bal., Cr 19.0 to 21.0, Si 1.0 to 1.7, Mn 1.0 max, C 0.10 max). The composition of the 80/20 grade is also given as 80 % nickel and 20 % chromium in the Goodfellow and Wikipedia pages.
  designations:
    - system: UNS
      code: N06003
      source: studersa-24869
      where: Page title and Description section, '2.4869 - Resistance alloy / NiCr 80-20 / N06003'
    - system: EN
      code: '2.4869'
      source: studersa-24869
      where: Page title and Description section, 'Material 2.4869'
    - system: EN name
      code: NiCr 80-20
      source: studersa-24869
      where: Page title and Description section, 'also known as NiCr 80-20'
    - system: ASTM
      code: B344
      source: bobmartin-8020
      where: Specification line of the 80/20 Nichrome Wire product page, printed as ASTM-B-344
    - system: DIN
      code: '17470'
      note: DIN 17470:1984-10, heating conductor alloys
      source: wikipedia-nichrome
      where: Designations section, DIN 17470:1984-10
    - system: Trade name
      code: Nichrome
      note: family name used for the 80/20 grade
      source: wikipedia-nichrome
      where: Page title; the article describes nichrome as a family of nickel-chromium alloys
tags:
  environments: []
  stresses:
    - extreme-heat
  applications:
    - thermal-control
    - electronics-and-chips
    - mechanisms
properties:
  - benchmark: density
    label: Density, Nikrothal 80 wire
    value: 8.3
    unit: g/cm3
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      temperature: not stated
      form: wire; the datasheet does not state a diameter for the physical values
    method: Value printed in a manufacturer datasheet
    status: ground
    source: kanthal-nikrothal80
    where: Physical properties section, Density
  - benchmark: density
    label: Density, Ni80/Cr20 wire (approximate)
    value: 8.4
    unit: g/cm3
    scope: material
    conditions:
      grade: Ni80/Cr20
      temperature: not stated
    method: Approximate value printed on a supplier material information page
    status: ground
    note: Goodfellow prints approximately 8.4 g/cm3, about 1 % above the 8.30 g/cm3 that Kanthal prints for Nikrothal 80. Both are kept; the Kanthal value is the datasheet figure.
    source: goodfellow-nicr80
    where: Material Overview section, density sentence
  - benchmark: melting_point
    label: Melting point, Nikrothal 80
    value: 1400
    unit: °C
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      pressure: not stated
    method: Value printed in a manufacturer datasheet
    status: ground
    source: kanthal-nikrothal80
    where: Physical properties section, Melting point
  - benchmark: electrical_resistivity
    label: Electrical resistivity at 20 °C, Nikrothal 80
    value: 1.09
    unit: Ω mm2/m
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      temperature: 20 °C
      form: wire; the datasheet does not state a diameter for this value
    method: Value printed in a manufacturer datasheet
    status: ground
    source: kanthal-nikrothal80
    where: Physical properties section, Electrical resistivity at 20°C
  - benchmark: electrical_resistivity
    label: Electrical resistivity, Ni80/Cr20 at room temperature
    value: 1.08
    value_high: 1.12
    bound: range
    unit: µΩ·m
    scope: material
    conditions:
      grade: Ni80/Cr20
      temperature: room temperature (not stated more precisely)
    method: Range printed on a supplier material information page
    status: ground
    note: Wikipedia prints about 1.12 µΩ·m for the 80/20 alloy and a family range of 1.0 to 1.5 µΩ·m. Kanthal's 1.09 Ohm mm2/m (1.09 µΩ·m) sits inside the Goodfellow range.
    source: goodfellow-nicr80
    where: Material Overview section, electrical resistivity sentence
  - benchmark: max_service_temp
    label: Maximum continuous operating temperature in air, Nikrothal 80
    value: 1200
    unit: °C
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      environment: air, continuous operation
      form: wire
    method: Value printed in a manufacturer datasheet
    status: ground
    source: kanthal-nikrothal80
    where: Physical properties section, Max continuous operating temperature in air
  - benchmark: max_service_temp
    label: Oxidation resistance limit, Ni80/Cr20 wire
    value: 1150
    unit: °C
    scope: material
    conditions:
      grade: Ni80/Cr20
      environment: air, high-temperature oxidation
    method: Limit printed on a supplier material information page
    status: ground
    note: The same Goodfellow page gives continuous-duty applications up to 1100 °C, below the 1150 °C oxidation limit, and Kanthal sets 1200 °C as the continuous limit. The three limits are not the same test.
    source: goodfellow-nicr80
    where: Material Overview section, oxidation resistance sentence
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 20 °C, Nikrothal 80
    value: 15
    unit: W/(m·K)
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      temperature: 20 °C
      unit_in_source: W m-1 K-1
    method: Value printed in a manufacturer datasheet
    status: ground
    source: kanthal-nikrothal80
    where: Thermal conductivity table, column Temp 20 °C
  - benchmark: specific_heat
    label: Specific heat capacity at 20 °C, Nikrothal 80
    value: 0.46
    unit: kJ/(kg·K)
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      temperature: 20 °C
      unit_in_source: kJ kg-1 K-1
    method: Value printed in a manufacturer datasheet
    status: ground
    source: kanthal-nikrothal80
    where: Specific heat capacity table, column Temp 20
  - benchmark: cte
    label: Coefficient of thermal expansion, 20 to 250 °C, Nikrothal 80
    value: 14.1
    unit: ppm/K
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      temperature: 20 to 250 °C
      unit_in_source: x10-6/K
    method: Value printed in a manufacturer datasheet
    status: ground
    source: kanthal-nikrothal80
    where: Coefficient of thermal expansion section, row 20 to 250 °C
  - benchmark: cte
    label: Coefficient of thermal expansion, 20 to 1000 °C, Nikrothal 80
    value: 17.2
    unit: ppm/K
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      temperature: 20 to 1000 °C
      unit_in_source: x10-6/K
    method: Value printed in a manufacturer datasheet
    status: ground
    source: kanthal-nikrothal80
    where: Coefficient of thermal expansion section, row 20 to 1000 °C
  - benchmark: yield_strength
    label: Yield strength Rp0.2, 1.0 mm wire, room temperature
    value: 420
    unit: MPa
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      form: wire, diameter 1.0 mm
      temperature: room temperature
      temper: not stated
    method: Value printed in a manufacturer datasheet
    status: ground
    source: kanthal-nikrothal80
    where: Mechanical properties, room temperature table, row 1.0 mm, column Yield Rp0.2
  - benchmark: yield_strength
    label: Yield strength Rp0.2, 4.0 mm wire, room temperature
    value: 300
    unit: MPa
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      form: wire, diameter 4.0 mm
      temperature: room temperature
      temper: not stated
    method: Value printed in a manufacturer datasheet
    status: ground
    source: kanthal-nikrothal80
    where: Mechanical properties, room temperature table, row 4.0 mm, column Yield Rp0.2
  - benchmark: ultimate_tensile_strength
    label: Tensile strength Rm, 1.0 mm wire, room temperature
    value: 810
    unit: MPa
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      form: wire, diameter 1.0 mm
      temperature: room temperature
      temper: not stated
    method: Value printed in a manufacturer datasheet
    status: ground
    source: kanthal-nikrothal80
    where: Mechanical properties, room temperature table, row 1.0 mm, column Tensile Rm
  - benchmark: ultimate_tensile_strength
    label: Tensile strength Rm, 4.0 mm wire, room temperature
    value: 725
    unit: MPa
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      form: wire, diameter 4.0 mm
      temperature: room temperature
      temper: not stated
    method: Value printed in a manufacturer datasheet
    status: ground
    source: kanthal-nikrothal80
    where: Mechanical properties, room temperature table, row 4.0 mm, column Tensile Rm
  - benchmark: ultimate_tensile_strength
    label: Ultimate tensile strength at 900 °C, Nikrothal 80
    value: 100
    unit: MPa
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      temperature: 900 °C
      deformation_rate: 6.2 x 10-2/min
      form: not stated
    method: Value printed in a manufacturer datasheet
    status: ground
    source: kanthal-nikrothal80
    where: Mechanical properties at elevated temperature section, Ultimate tensile strength at 900 °C
  - benchmark: elongation
    label: Elongation A, 1.0 mm wire, room temperature
    value: 30
    unit: '%'
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      form: wire, diameter 1.0 mm
      temperature: room temperature
      temper: not stated
    method: Value printed in a manufacturer datasheet
    status: ground
    source: kanthal-nikrothal80
    where: Mechanical properties, room temperature table, row 1.0 mm, column Elongation A
  - benchmark: hardness_vickers
    label: Hardness Hv, 1.0 mm wire, room temperature
    value: 180
    unit: HV
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      form: wire, diameter 1.0 mm
      temperature: room temperature
    method: Value printed in a manufacturer datasheet
    status: ground
    note: Non-canonical property name; hardness_vickers is not in the canonical property file.
    source: kanthal-nikrothal80
    where: Mechanical properties, room temperature table, row 1.0 mm, column Hardness (Hv)
  - benchmark: creep_strength_1pct_1000h
    label: Creep strength for 1 % elongation in 1000 h at 800 °C, Nikrothal 80
    value: 15
    unit: MPa
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      temperature: 800 °C
      time: 1000 h
      criterion: 1 % elongation
    method: Value printed in a manufacturer datasheet
    status: ground
    note: Non-canonical property name; the datasheet gives it under the elevated temperature mechanical properties section.
    source: kanthal-nikrothal80
    where: Mechanical properties at elevated temperature section, Creep strength, 1 % elongation in 1000 h, 800 °C
  - benchmark: creep_strength_1pct_1000h
    label: Creep strength for 1 % elongation in 1000 h at 1000 °C, Nikrothal 80
    value: 4
    unit: MPa
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      temperature: 1000 °C
      time: 1000 h
      criterion: 1 % elongation
    method: Value printed in a manufacturer datasheet
    status: ground
    note: Non-canonical property name.
    source: kanthal-nikrothal80
    where: Mechanical properties at elevated temperature section, Creep strength, 1 % elongation in 1000 h, 1000 °C
  - benchmark: emissivity
    label: Emissivity, fully oxidized material
    value: 0.88
    unit: '-'
    scope: material
    conditions:
      grade: Nikrothal 80 (Kanthal)
      surface: fully oxidized
    method: Value printed in a manufacturer datasheet
    status: ground
    note: Non-canonical property name. The datasheet gives this for fully oxidized material only.
    source: kanthal-nikrothal80
    where: Physical properties section, Emissivity
corrosion:
  - environment: Air at high temperature
    headline: A chromium oxide scale protects the alloy from oxidation up to about 1150 °C.
    effect: Goodfellow attributes the high-temperature oxidation resistance to a protective chromium oxide (Cr2O3) scale and gives the limit as up to 1150 °C. The page gives no oxidation rate or weight gain.
    rating: low
    conditions:
      environment: air
      basis: supplier material information page; no test duration stated
    source: goodfellow-nicr80
    where: Material Overview section, oxidation resistance sentence
  - environment: Air, continuous operation at elevated temperature
    headline: Kanthal rates the wire for continuous use in air up to 1200 °C.
    effect: The datasheet gives 1200 °C as the maximum continuous operating temperature in air and describes the alloy as having good oxidation resistance and very good form stability. No mass loss or scale thickness is given.
    rating: low
    conditions:
      environment: air
      form: wire
    source: kanthal-nikrothal80
    where: Physical properties section, Max continuous operating temperature in air; description paragraph
risks:
  hazards:
    - text: 'Airgas nickel wire and rod safety data sheet (approval 2-1-2016): GHS Hazard Classification is ''Not Classified'' and the label has no symbol or signal word. This sheet covers a nickel wire and rod product whose list includes 80/20 nickel-chromium; the sheet does not name Ni80/Cr20 as a product of its own.'
      ghs: []
      source: airgas-nickel-sds
      where: Section 2, GHS Hazard Classification line; header block with approval date
    - text: The same Airgas sheet lists nickel (listed 10-1-1989) and hexavalent chromium compounds (listed 2-27-1987) under California Proposition 65 carcinogens.
      ghs: []
      source: airgas-nickel-sds
      where: Regulatory information section, California Proposition 65 line
  failure_risks:
    - mode: Oxidation above the service limit
      trigger: Operation above 1200 °C continuous in air (Kanthal), or above the 1150 °C oxidation limit (Goodfellow)
      consequence: Both sources give a temperature limit. Neither gives an oxidation rate, so the time to failure above the limit cannot be taken from these sources.
      severity: moderate
      source: kanthal-nikrothal80
      where: Physical properties section, Max continuous operating temperature in air; see also goodfellow-nicr80 Material Overview
    - mode: Creep sag under sustained load at high temperature
      trigger: A sustained stress at 800 °C or above, for example a wire carrying a tension load in a furnace
      consequence: The datasheet gives 15 MPa for 1 % elongation in 1000 h at 800 °C and 4 MPa at 1000 °C, so the allowable sustained stress falls sharply with temperature.
      severity: moderate
      source: kanthal-nikrothal80
      where: Mechanical properties at elevated temperature section, Creep strength rows
  side_effects:
    - text: Nickel and chromium make up nearly all of the alloy, so the sources classify its raw materials, not the finished wire, as the hazard. Airgas lists nickel and hexavalent chromium compounds on Proposition 65.
      affects: Handling of dust and fume from grinding or welding
      source: airgas-nickel-sds
      where: Regulatory information section, California Proposition 65 line
  handling:
    - text: The datasheet gives a maximum continuous operating temperature of 1200 °C in air. Use a lower limit for loaded wires, since creep strength at 800 °C is only 15 MPa for 1 % elongation in 1000 h.
      source: kanthal-nikrothal80
      where: Physical properties section; Mechanical properties at elevated temperature section
  mitigations: []
uses:
  - application: thermal-control
    device: Resistance heating elements
    example: Goodfellow lists heating elements in electric furnaces, kilns, toasters, hair dryers and industrial heating equipment. Wikipedia lists hair dryers, heat guns, toasters, kettles and space heaters.
    source: goodfellow-nicr80
    where: Applications and Advantages section, Heating elements; Wikipedia Uses section
  - application: electronics-and-chips
    device: Precision wire-wound resistors
    example: Goodfellow lists precision wire-wound resistors for power electronics and load banks.
    source: goodfellow-nicr80
    where: Applications and Advantages section, Resistors
  - application: mechanisms
    device: Burn-wire release actuator for a CubeSat tie-down
    example: A JPL tie-down and release mechanism uses 30 AWG (.010 in diameter) Nichrome wire carrying a 1.6-amp current for about 5 to 10 seconds to cut a Vectran tie-off cable. The brief is dated June 1, 2016.
    source: jpl-cubesat-tiedown
    where: Description and Nichrome wire size paragraphs
  - application: mechanisms
    device: Solar panel deployment mechanism
    example: Wikipedia says nichrome is used in the solar panel deployment mechanism of spacecraft, citing LightSail-A.
    source: wikipedia-nichrome
    where: Uses section, Space paragraph
supply:
  - subject: Nickel
    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
    recycling: 'USGS: nickel recovered from scrap accounted for approximately 60 % of apparent consumption in 2025. Most secondary nickel is stainless-steel scrap.'
    substitutes:
      - 'USGS: low-nickel, duplex or ultrahigh-chromium stainless steels replace austenitic grades in some uses; 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 (world total 3,900,000 t; shares calculated by Space Mushroom against that printed total); Recycling; Substitutes; Domestic Production and Use (stainless and alloy steel and nickel-containing alloys are more than 85 % of U.S. consumption)
  - subject: Chromium
    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
    recycling: 'USGS: recycled chromium in reported stainless-steel scrap receipts accounted for 21 % of supply in 2025.'
    substitutes:
      - 'USGS: chromium has no substitute in stainless steel or in superalloys.'
    source: usgs-mcs2026-chromium
    where: World Mine Production and Reserves table, 2025e column (world total 51,000 thousand t; shares calculated by Space Mushroom against that printed total; Kazakhstan value is estimated by USGS); Recycling; Substitutes; Net import reliance 79 % of apparent consumption in 2025e
documents:
  - title: 'Bob Martin Co.: 80/20 Nichrome Wire product page (ASTM-B-344, UNS N06003)'
    type: datasheet
    url: https://www.bobmartinco.com/product/nichromenichrome-and-resistance-alloys/
  - title: Kanthal Nikrothal 80 wire datasheet (updated 2024-09-05)
    type: datasheet
    url: https://kanthal.com/en/products/datasheets/material-datasheets/wire/resistance-heating-wire-and-resistance-wire/nikrothal-80
  - title: 'Goodfellow: Nickel/Chromium Ni80/Cr20 wire material information'
    type: datasheet
    url: https://www.goodfellow.com/usa/resources/nickel-chromium-ni80-cr20-wire-material-information/
  - title: 'Wikipedia: Nichrome'
    type: database
    url: https://en.wikipedia.org/wiki/Nichrome
  - title: 'Studer SA: 2.4869 Resistance alloy NiCr 80-20 / N06003'
    type: datasheet
    url: https://www.studersa.com/en/materials/24869-resistance-alloy-nicr-80-20-n06003;144
  - title: 'NASA JPL: Launch Tie-Down and Release Mechanism for CubeSat Spacecraft (Tech Briefs NPO-49969, June 1, 2016)'
    type: report
    url: https://www.techbriefs.com/component/content/article/24810-npo-49969
    year: 2016
  - 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: Chromium'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf
    year: 2026
  - title: Airgas Nickel Wire and Rod safety data sheet, SDS number 011-Ni Wire and Rod (approval 2-1-2016)
    type: sds
    url: https://www.airgas.com/msds/005727.pdf
    year: 2016
gaps:
  - Hardness, emissivity and creep strength are listed under non-canonical names (hardness_vickers, emissivity, creep_strength_1pct_1000h) because the canonical property file has no entry for them.
  - Strength values are for wire of 1.0 mm and 4.0 mm diameter as the datasheet prints them; the temper or condition of the wire is not stated.
  - No CAS number was recorded for the alloy. The search results gave 11106-97-1 for a nickel-chromium product, but no fetched page printed it for this alloy.
  - 'Hazard classification: Fisher Scientific and Thomas Scientific listings of 80/20 nickel-chromium wire carry H317 and H351 in search snippets, but the Fisher page did not load, so these codes are not recorded. The Airgas sheet classifies its nickel wire as Not Classified. PubChem could not be read in this run.'
  - 'Critical-mineral list status for nickel and chromium: the USGS 2026 nickel and chromium summaries were read and do not name a critical-minerals list in the text extracted, so no list entry is recorded.'
  - 'Corrosion: no sulphur, chloride, humidity or vacuum attack data were found. No corrosion rate in micrometres per year was found.'
  - Outgassing, atomic-oxygen and radiation effects on NiCr wire were not looked up, and no NASA outgassing value was found.
  - Reliable mechanical values for the annealed or as-drawn temper were not found, because the Bob Martin and Ulbrich pages gave no property values and the Ulbrich PDF did not load.
  - The Ulbrich and NiWire datasheets (cloud-hosted PDFs) could not be read in this run.
  - 'Fe content: the Kanthal page prints an iron limit of Fe 1.0 max on request in one place and a table value of 2.0 max elsewhere, so the iron limit is left out of the composition.'
  - Atomic weights of nickel and chromium were not read from a fetched page, so the recipe parts carry shares only.
sources:
  bobmartin-8020:
    title: 80/20 Nichrome Wire and Nichrome and resistance alloys (Bob Martin Co.)
    url: https://www.bobmartinco.com/product/nichromenichrome-and-resistance-alloys/
    kind: web
    license: Supplier product page (cited, not reproduced)
  kanthal-nikrothal80:
    title: Nikrothal 80 wire material datasheet (Kanthal), updated 2024-09-05
    url: https://kanthal.com/en/products/datasheets/material-datasheets/wire/resistance-heating-wire-and-resistance-wire/nikrothal-80
    year: 2024
    kind: datasheet
    license: Manufacturer datasheet (cited, not reproduced)
  goodfellow-nicr80:
    title: 'Nickel/Chromium Ni80/Cr20 Wire: material information (Goodfellow)'
    url: https://www.goodfellow.com/usa/resources/nickel-chromium-ni80-cr20-wire-material-information/
    kind: web
    license: Supplier web page (cited, not reproduced)
  wikipedia-nichrome:
    title: Nichrome (Wikipedia)
    url: https://en.wikipedia.org/wiki/Nichrome
    year: 2026
    kind: web
    license: CC BY-SA 4.0 (cited, not reproduced)
  studersa-24869:
    title: 2.4869 Resistance alloy NiCr 80-20 / N06003 (Studer SA)
    url: https://www.studersa.com/en/materials/24869-resistance-alloy-nicr-80-20-n06003;144
    kind: web
    license: Supplier web page (cited, not reproduced)
  jpl-cubesat-tiedown:
    title: Launch Tie-Down and Release Mechanism for CubeSat Spacecraft (NASA JPL, Tech Briefs NPO-49969)
    url: https://www.techbriefs.com/component/content/article/24810-npo-49969
    year: 2016
    kind: report
    license: NASA JPL tech brief reprinted by Tech Briefs (cited, not reproduced)
  usgs-mcs2026-nickel:
    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-mcs2026-chromium:
    title: Mineral Commodity Summaries 2026, Chromium
    id: USGS MCS 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  airgas-nickel-sds:
    title: Safety Data Sheet, Nickel Wire and Rod, SDS number 011-Ni Wire and Rod (Airgas)
    url: https://www.airgas.com/msds/005727.pdf
    year: 2016
    kind: datasheet
    license: Supplier safety data sheet (cited, not reproduced)
license: CC-BY-4.0
updated: '2026-10-26'
review:
  status: draft
  method: assistant
  checked_values: 21
  unreachable: 4
  caveats: 5
  note: 'Values were read by an AI assistant on 2026-10-26 from the pages named in each entry. Kanthal values are from the manufacturer datasheet for Nikrothal 80. Goodfellow values are approximate and are stated as approximate on the page. Unreachable in this run: PubChem, the Fisher Scientific product page, the Ulbrich PDF and the NiWire PDF. Caveats: the strength values are from wire of two diameters with no temper stated; the 8.4 g/cm3 density and 1.08 to 1.12 µΩ·m resistivity range are approximate supplier values; the nickel and chromium shares are calculated from printed world totals; the Airgas sheet is for a nickel wire and rod product, not the alloy itself.'
story:
  risk_groups:
    - title: For people
      lead: The alloy is about 80 % nickel and 20 % chromium. The sources do not agree on its hazard classification, so the raw materials are the better guide.
      level: 1
      verdict: Mixed classification
      points:
        - label: Supplier classification
          line: The Airgas nickel wire and rod sheet is classified as Not Classified under GHS and has no signal word. Other suppliers' listings of 80/20 nickel-chromium wire, seen only in search snippets, carry H317 and H351.
        - label: Proposition 65
          line: The same Airgas sheet lists nickel and hexavalent chromium compounds as carcinogens under California Proposition 65.
    - title: If it fails
      lead: The failure routes in the sources are temperature and load. The datasheet gives limits but no failure rates.
      points:
        - label: Overheating
          line: Kanthal gives 1200 °C as the continuous limit in air. Goodfellow gives an oxidation limit of 1150 °C. Neither source gives a time to failure above these limits.
        - label: Creep
          line: At 800 °C the datasheet gives 15 MPa for 1 % elongation in 1000 h, and at 1000 °C it gives 4 MPa.
    - title: Handling and storage
      points:
        - label: Keep it below the limit
          line: Kanthal gives 1200 °C as the maximum continuous operating temperature in air. Keep loaded wires below that and well below it when they carry tension.
  why: Nichrome is a heating alloy. It combines high electrical resistance with a protective chromium oxide scale, so it can carry current and turn it into heat in air at high temperature. Kanthal's Nikrothal 80 wire has a resistivity of 1.09 Ohm mm2/m at 20 °C, a melting point of 1400 °C and a continuous limit of 1200 °C in air. It is found in heating elements, in precision resistors, and in burn-wire release mechanisms on CubeSats. Its weak points are its low thermal conductivity, 15 W/(m·K) at 20 °C, and its loss of strength at temperature.
  uses:
    - where: Heating elements
      line: Heating elements are the main use. Goodfellow lists electric furnaces, kilns, toasters, hair dryers and industrial heating equipment, and Wikipedia adds kettles, heat guns and space heaters.
    - where: Burn-wire releases in CubeSats
      line: A JPL tie-down and release mechanism uses 30 AWG nichrome wire to cut a Vectran cable. The source gives a current of 1.6 A applied for about 5 to 10 seconds.
    - where: Solar panel deployment
      line: Wikipedia says nichrome is used in the solar panel deployment mechanism of spacecraft, citing LightSail-A.
  can_do:
    - label: Carry current as a heater
      value: 1.09 Ohm mm2/m
      benchmark: electrical_resistivity
      line: The electrical resistivity of Nikrothal 80 is 1.09 Ohm mm2/m at 20 °C, and the Goodfellow range is 1.08 to 1.12 µΩ·m at room temperature.
    - label: Stay solid when hot
      value: 1400 °C melting point
      benchmark: melting_point
      line: The melting point is 1400 °C. The continuous operating limit in air is 1200 °C.
    - label: Stay light
      value: 8.30 g/cm3
      benchmark: density
      line: Density is 8.30 g/cm3 in the Kanthal datasheet, and about 8.4 g/cm3 in the Goodfellow page.
    - label: Strength in fine wire
      value: 810 MPa tensile
      benchmark: ultimate_tensile_strength
      line: In 1.0 mm wire the datasheet gives 810 MPa tensile strength, 420 MPa yield and 30 % elongation at room temperature.
  compare: 'This profile has no second heating alloy read in the same run, so the compare rows use nichrome''s own figures: resistivity, continuous temperature limit and thermal conductivity. Read them as nichrome''s values, not as a ranking against another metal.'
  compare_rows:
    - label: Electrical resistivity
      benchmark: electrical_resistivity
    - label: Max continuous temperature
      benchmark: max_service_temp
    - label: Thermal conductivity
      benchmark: thermal_conductivity
  handling:
    - Keep continuous service at or below 1200 °C in air (Kanthal).
    - 'Derate for tension at temperature: 15 MPa gives 1 % creep in 1000 h at 800 °C.'
    - Treat dust and fume from grinding or welding as containing nickel and chromium compounds (Airgas Proposition 65 listing).
  good_for:
    - 'Heating elements: 1.09 Ohm mm2/m resistivity and a continuous limit of 1200 °C in air (Kanthal).'
    - 'Oxidation resistance: a chromium oxide scale resists oxidation up to about 1150 °C (Goodfellow).'
    - 'Fine wire at room temperature: 810 MPa tensile strength and 30 % elongation for 1.0 mm wire (Kanthal).'
  watch_out:
    - 'Creep: 15 MPa for 1 % elongation in 1000 h at 800 °C, and 4 MPa at 1000 °C.'
    - 'Low thermal conductivity: 15 W/(m·K) at 20 °C.'
    - 'Hazard classification varies by supplier: Airgas classifies its nickel wire as Not Classified.'
    - No corrosion rate, outgassing or radiation data were found.
  verdict: Nichrome 80/20 is the standard heating alloy, with a resistivity of 1.09 Ohm mm2/m, a 1400 °C melting point and a 1200 °C continuous limit in air. It is a good choice for a heater, but its strength falls sharply at 800 °C and above, and the profile has no corrosion-rate, outgassing or radiation values.
  recipe:
    line: Nichrome is a two-element alloy of nickel and chromium, about 80 % nickel and 20 % chromium by mass (Wikipedia, Goodfellow and Studer SA). Kanthal's datasheet gives the chromium range as 19.0 to 21.0 %, with nickel as the balance.
    parts:
      - name: Nickel
        symbol: Ni
        share_percent: 80
        role: The matrix of the alloy. The balance of the Kanthal composition is nickel.
      - name: Chromium
        symbol: Cr
        share_percent: 20
        role: Forms the protective chromium oxide (Cr2O3) scale that resists oxidation in air (Goodfellow).