Tungsten-rhenium alloys W-Re

spore: profile
id: tungsten-rhenium
spore_version: 0.2
family: refractory-metals
name: Tungsten-rhenium alloys
abbreviation: W-Re
role: refractory alloy for high-temperature thermocouples, X-ray target tracks and nuclear-space design studies
category: metals
type: refractory-metals
summary: |
  Tungsten-rhenium alloys add rhenium to tungsten to make it less brittle and easier to fabricate. The grades are named by rhenium content (W-3Re, W-5Re, W-26Re). The Concept Alloys data sheet gives a density of 19.4 g/cm3 for W-5Re and 19.7 g/cm3 for the W25/26Re column, and melting points of 3350 °C and 3120 °C. The W-5Re against W-26Re thermocouple pair has had the widest acceptance in industry. Rhenium-bearing tungsten also forms the focal track of rotating X-ray anodes. The same data sheet warns that these alloys oxidise rapidly at high temperature and are not recommended in oxidising environments.
best_for: High-temperature thermocouples and X-ray target tracks, used in reducing, inert or vacuum conditions where pure tungsten is too brittle
weakest_at: Rapid oxidation at high temperature in air or other oxidising gas (the data sheet says not recommended there)
identity:
  formula: Tungsten with rhenium added; grades W-3Re, W-5Re and W-26Re, where the number is the rhenium content in the grade name
  source: klopp-tnd3483
  where: Abstract, commercial arc-melted 26-percent-rhenium alloy (grade naming); the composition columns of the Concept Alloys data sheet are headed W3Re, W5Re and W25/26Re
tags:
  environments: []
  stresses: []
  applications:
    - thermal-control
    - structures
    - electronics-and-chips
properties:
  - benchmark: density
    label: Density, W-5Re
    value: 19.4
    unit: g/cm3
    scope: material
    conditions:
      basis: W5Re column of the wrought alloy table; no temperature stated
    method: Printed in the mechanical and physical properties table of the Concept Alloys data sheet
    status: ground
    source: concept-wre-ds
    where: Mechanical Properties and Physical Properties table, row Density, column W5Re (page 2 of 2)
  - benchmark: density
    label: Density, W25/26Re column
    value: 19.7
    unit: g/cm3
    scope: material
    conditions:
      basis: W25/26Re column of the wrought alloy table (the column covers the 25 and 26 percent rhenium grades together); no temperature stated
    method: Printed in the mechanical and physical properties table of the Concept Alloys data sheet
    status: ground
    source: concept-wre-ds
    where: Mechanical Properties and Physical Properties table, row Density, column W25/26 Re (page 2 of 2)
  - benchmark: melting_point
    label: Melting point, W-5Re
    value: 3350
    unit: °C
    scope: material
    conditions:
      basis: W5Re column of the wrought alloy table
    method: Printed in the mechanical and physical properties table of the Concept Alloys data sheet
    status: ground
    source: concept-wre-ds
    where: Mechanical Properties and Physical Properties table, row Melting Point, column W5Re
  - benchmark: melting_point
    label: Melting point, W25/26Re column
    value: 3120
    unit: °C
    scope: material
    conditions:
      basis: W25/26Re column of the wrought alloy table
    method: Printed in the mechanical and physical properties table of the Concept Alloys data sheet
    status: ground
    source: concept-wre-ds
    where: Mechanical Properties and Physical Properties table, row Melting Point, column W25/26 Re
  - benchmark: electrical_resistivity
    label: Electrical resistivity, W-5Re at 68 °F
    value: 70
    unit: circ mil/ft
    scope: material
    conditions:
      temperature: 68 °F
      form: annealed wrought alloy as printed (Resistivity row)
    method: Printed in the resistivity row of the Concept Alloys data sheet
    status: ground
    source: concept-wre-ds
    where: Mechanical Properties and Physical Properties table, Resistivity row, 68 °F line, column W5Re
  - benchmark: electrical_resistivity
    label: Electrical resistivity, W25/26Re at 68 °F
    value: 170
    unit: circ mil/ft
    scope: material
    conditions:
      temperature: 68 °F
      form: wrought alloy, W25/26Re column as printed
    method: Printed in the resistivity row of the Concept Alloys data sheet
    status: ground
    source: concept-wre-ds
    where: Mechanical Properties and Physical Properties table, Resistivity row, 68 °F line, column W25/26 Re
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, W-5Re annealed at 68 °F
    value: 220
    unit: x 10^3 psi
    scope: material
    conditions:
      temperature: 68 °F
      form: annealed wrought W5Re, as printed
    method: Printed as tensile strength, annealed, in the Concept Alloys data sheet
    status: ground
    source: concept-wre-ds
    where: Mechanical Properties and Physical Properties table, Tensile Strength ann. row, 68 °F line, column W5Re
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, W-5Re annealed at 1832 °F
    value: 65
    unit: x 10^3 psi
    scope: material
    conditions:
      temperature: 1832 °F
      form: annealed wrought W5Re, as printed
    method: Printed as tensile strength, annealed, in the Concept Alloys data sheet
    status: ground
    source: concept-wre-ds
    where: Mechanical Properties and Physical Properties table, Tensile Strength ann. row, 1832 °F line, column W5Re
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, W-5Re annealed at 3632 °F
    value: 26
    unit: x 10^3 psi
    scope: material
    conditions:
      temperature: 3632 °F
      form: annealed wrought W5Re, as printed
    method: Printed as tensile strength, annealed, in the Concept Alloys data sheet
    status: ground
    source: concept-wre-ds
    where: Mechanical Properties and Physical Properties table, Tensile Strength ann. row, 3632 °F line, column W5Re
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, W25/26Re annealed at 68 °F
    value: 200
    unit: x 10^3 psi
    scope: material
    conditions:
      temperature: 68 °F
      form: annealed wrought W25/26Re column, as printed
    method: Printed as tensile strength, annealed, in the Concept Alloys data sheet
    status: ground
    source: concept-wre-ds
    where: Mechanical Properties and Physical Properties table, Tensile Strength ann. row, 68 °F line, column W25/26 Re
  - benchmark: elongation
    label: Elongation, W-5Re at 68 °F
    value: 20
    unit: '%'
    scope: material
    conditions:
      temperature: 68 °F
      gauge: '% in 10 in, as printed'
    method: Printed as elongation in the Concept Alloys data sheet
    status: ground
    source: concept-wre-ds
    where: Mechanical Properties and Physical Properties table, Elongation row, 68 °F line, column W5Re
  - benchmark: elongation
    label: Elongation, W25/26Re at 68 °F
    value: 11
    unit: '%'
    scope: material
    conditions:
      temperature: 68 °F
      gauge: '% in 10 in, as printed'
    method: Printed as elongation in the Concept Alloys data sheet
    status: ground
    source: concept-wre-ds
    where: Mechanical Properties and Physical Properties table, Elongation row, 68 °F line, column W25/26 Re
  - benchmark: ductile_brittle_transition_temperature
    label: Ductile-brittle transition, unalloyed recrystallized tungsten
    value: 490
    unit: K
    scope: material
    conditions:
      form: vacuum arc-melted, recrystallized unalloyed tungsten (comparison, not an alloy)
      test: low-temperature bend and tension, 77 to 810 K range of the study
    method: Stated in the abstract of the NASA technical note
    status: ground
    source: raffo-tnd4567
    where: Abstract, first sentence on transition temperature
  - benchmark: ductile_brittle_transition_temperature
    label: Ductile-brittle transition, arc-melted W-25Re
    value: 350
    unit: K
    scope: material
    conditions:
      form: vacuum arc-melted tungsten with 25 percent rhenium, recrystallized
      test: low-temperature yield and fracture tests, 77 to 810 K range of the study
    method: Stated in the abstract of the NASA technical note
    status: ground
    source: raffo-tnd4567
    where: Abstract, transition temperature reduced to 350 K by 25 percent rhenium
  - benchmark: ductile_brittle_transition_temperature
    label: Bend transition, arc-melted 26 percent Re worked sheet
    value: -150
    unit: °F
    scope: material
    conditions:
      form: arc-melted 26-percent-rhenium alloy, worked sheet (as worked, before the 3600 °F anneal)
      test: bend transition temperature
    method: Stated in the abstract of the NASA technical note
    status: ground
    source: klopp-tnd3483
    where: Abstract, transition temperatures for the arc-melted 26-percent-rhenium alloy
  - benchmark: ductile_brittle_transition_temperature
    label: Bend transition, arc-melted 26 percent Re after 3600 °F anneal
    value: 350
    unit: °F
    scope: material
    conditions:
      form: arc-melted 26-percent-rhenium alloy, recrystallized by anneal at 3600 °F
      test: bend transition temperature
    method: Stated in the abstract of the NASA technical note
    status: ground
    source: klopp-tnd3483
    where: Abstract, 24- and 26-percent-rhenium alloys after the 3600 °F anneal
  - benchmark: density
    label: Density, unalloyed tungsten column (comparison)
    value: 19.3
    unit: g/cm3
    scope: material
    conditions:
      basis: tungsten column of the same table, no temperature stated; comparison only
    method: Printed in the mechanical and physical properties table of the Concept Alloys data sheet
    status: ground
    source: concept-wre-ds
    where: Mechanical Properties and Physical Properties table, row Density, column Tungsten (page 2 of 2)
  - benchmark: atomic_weight
    label: Atomic weight of tungsten (matrix element)
    value: 183.84
    unit: g/mol
    scope: material
    conditions:
      basis: relative atomic mass of the element as printed
    method: Relative atomic mass line on the WebElements tungsten page
    status: ground
    source: webel-w
    where: 'Tungsten - 74W: the essentials, relative atomic mass'
  - benchmark: atomic_weight
    label: Atomic weight of rhenium (alloying element)
    value: 186.207
    unit: g/mol
    scope: material
    conditions:
      basis: relative atomic mass of the element as printed, with uncertainty (1) not shown here
    method: Relative atomic mass line on the WebElements rhenium page
    status: ground
    source: webel-re
    where: 'Rhenium - 75Re: the essentials, relative atomic mass'
corrosion:
  - environment: Oxidising atmosphere at high temperature (air)
    headline: Rapid oxidation at high temperature; not recommended for oxidising environments.
    effect: The Concept Alloys data sheet says both W-Re combinations are susceptible to rapid oxidation at high temperatures and are not recommended for use in oxidising environments.
    rating: severe
    conditions:
      basis: qualitative data sheet statement; no temperature, pressure or time given
    source: concept-wre-ds
    where: Introduction paragraph of the data sheet
  - environment: Reducing or inert atmosphere and vacuum at high temperature
    headline: Very stable at high temperature in reducing or inert atmospheres and vacuum.
    effect: The data sheet says the alloy combinations are very stable at high temperatures in reducing or inert atmospheres such as hydrogen, inert gases and vacuum.
    rating: low
    conditions:
      basis: qualitative statement; no temperature given
    source: concept-wre-ds
    where: Introduction paragraph of the data sheet
  - environment: Supplier description of oxidation resistance (no atmosphere or grade stated)
    headline: Supplier claims oxidation resistance, which conflicts with the data sheet warning.
    effect: Goodfellow describes tungsten-rhenium as having excellent thermal stability, oxidation resistance and mechanical robustness, with service up to 2500 °C. The page gives no atmosphere, temperature or grade, so it is not used to rate corrosion.
    rating: unknown
    conditions:
      basis: general product description; no atmosphere, temperature or grade stated
    source: goodfellow-wre
    where: Applications and Advantages section, and introductory paragraph
risks:
  hazards:
    - text: Rhenium metal safety data sheet (Angstrom Sciences, revised 2015) gives the signal word Warning and H228, flammable solid. It states that the metal is hazardous as a powder only.
      ghs:
        - H228
      source: angstrom-re-sds
      where: Section 2, Hazard Statements; transport section, Hazardous as powder only
    - text: Tungsten powder 99.9 percent safety data sheet (Fujifilm Wako) gives the signal word Warning, H320 (causes eye irritation) and H335 (may cause respiratory irritation).
      ghs:
        - H320
        - H335
      source: wako-w-sds
      where: Section 2, Hazard statements
    - text: 'Tungsten safety data sheet (Stanford Advanced Materials, revised 2012): tungsten powder may present a fire or explosion hazard under favoring conditions of particle size, dispersion and strong ignition source. Most studies show tungsten to be toxicologically inert, but dust can irritate the nose, throat, skin and eyes.'
      ghs: []
      source: sam-w-msds
      where: Section IV, Fire and explosion hazard data; Section VI, Health hazard data
  failure_risks:
    - mode: Brittle fracture of cold parts
      trigger: Bending or handling below the bend transition temperature
      consequence: NASA TN D-3483 gives a bend transition of -150 °F for arc-melted 26 percent rhenium worked sheet, against 215 °F for unalloyed arc-melted tungsten sheet. NASA TN D-4567 gives 350 K for 25 percent rhenium and 490 K for unalloyed recrystallized tungsten.
      severity: moderate
      source: klopp-tnd3483
      where: Abstract, bend transition temperatures
    - mode: Oxidation at high temperature
      trigger: Exposure to air or another oxidising gas at high temperature
      consequence: The alloys oxidise rapidly and the data sheet does not recommend them in oxidising environments.
      severity: high
      source: concept-wre-ds
      where: Introduction paragraph of the data sheet
    - mode: Powder fire
      trigger: Fine powder dispersed in air near an ignition source
      consequence: Rhenium powder is classed as a flammable solid (H228). Tungsten powder may present a fire or explosion hazard under favoring conditions of particle size and dispersion.
      severity: moderate
      source: angstrom-re-sds
      where: Section 2, H228
  handling:
    - text: Use the alloys at high temperature only in reducing, inert or vacuum conditions. The data sheet says they are very stable there and not recommended in oxidising environments.
      source: concept-wre-ds
      where: Introduction paragraph of the data sheet
    - text: Keep powder away from strong oxidisers and acids. Contact with acids may generate flammable hydrogen gas, and the SDS lists strong oxidisers as incompatible.
      source: sam-w-msds
      where: Section V, Reactivity data
    - text: Keep dust from accumulating and keep ignition sources away from it, as tungsten powder may present a fire or explosion hazard.
      source: sam-w-msds
      where: Section IV, Fire and explosion hazard data
  mitigations:
    - text: The data sheet says wrought W5Re and W26Re are shipped in a stabilised condition and keep good room-temperature ductility after heating above 3000 °F. It limits use to 3000 °F or lower to keep that ductility.
      source: concept-wre-ds
      where: Introduction paragraph of the data sheet
uses:
  - application: thermal-control
    device: Insulated W+26Re and W+5Re/W+26Re thermocouples in a UO2-fuelled reactor
    example: AEC-NASA Tech Brief 68-10109 says these tungsten-rhenium thermocouples are effective for temperature measurement in excess of 2920 °C. A pure tungsten leg was found too brittle, so a W+5Re leg was used instead.
    source: nasa-tb-68-10109
    where: Brief 68-10109, The solution and How it's done sections
  - application: thermal-control
    device: Gas-temperature probe with a tungsten-26 percent rhenium plug and tungsten-5 percent rhenium probe
    example: NASA Tech Brief 66-10134 describes a probe for measuring a flowing gas up to 4500 °F in a hazardous radiation environment, built from tungsten-26 percent rhenium and tungsten-5 percent rhenium wire insulated with beryllia.
    source: nasa-tb-66-10134
    where: Brief 66-10134, description of the probe
  - application: structures
    device: Thermionic converter cathode tube in a nuclear space powerplant design study (not flown)
    example: A Pratt and Whitney design study for an in-pile nuclear thermionic space powerplant considers W-25Re superior to tungsten for the cathode tube, because tungsten has a brittle-ductile transition of 400 to 600 °F that makes it hard to fabricate. The scanned text says W-25Re has room-temperature ductility, but its compatibility with the fuel needs documentation.
    source: pw-thermionic-1965
    where: Refractory materials discussion, cathode tube section (OCR scan)
  - application: electronics-and-chips
    device: Focal track of a rotating X-ray anode
    example: Plansee says its rotating anodes use molybdenum-alloy bodies (TZM, MHC or MoNb) with focal tracks made of various tungsten-rhenium alloys. The page does not give a rhenium percentage.
    source: plansee-xray
    where: Rotating anodes, focal track material
supply:
  - subject: Tungsten (mine production shares computed from USGS 2025 tonnes of contained W, world total 85,000 t)
    abundance: Crustal abundance not read in the USGS tungsten summary (see gaps).
    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
      - country: Bolivia
        share_percent: 2
        year: 2025
      - country: Australia
        share_percent: 1.2
        year: 2025
    critical_lists: []
    recycling: The USGS withholds the 2025 secondary tungsten quantity to avoid disclosing company data, so the recycling share is not given.
    source: usgs-mcs2026-tungsten
    where: World Mine Production and Reserves table, 2025 column (shares computed by Space Mushroom against the 85,000 t world total)
  - subject: Rhenium (mine production shares computed from USGS 2025 kilograms of contained rhenium, world total 81,000 kg)
    abundance: Crustal abundance not read (see gaps).
    producers:
      - country: Chile
        share_percent: 37
        year: 2025
      - country: China
        share_percent: 24.7
        year: 2025
      - country: Poland
        share_percent: 12.3
        year: 2025
      - country: United States
        share_percent: 12.1
        year: 2025
      - country: Uzbekistan
        share_percent: 8.6
        year: 2025
    critical_lists:
      - list: USGS 2025 List of Critical Minerals (rhenium added in the 2025 list)
        listed: true
    recycling: Nickel-base superalloy scrap, scrapped turbine parts and spent catalysts are recycled. Industry sources estimated 2025 global secondary production at 20,000 to 25,000 kg (USGS).
    substitutes:
      - 'USGS: cobalt and tungsten for coatings on copper X-ray targets; rhodium and rhodium-iridium for high-temperature thermocouples; tungsten and tantalum for electron emitters.'
    source: usgs-mcs2026-rhenium
    where: World Mine Production and Reserves table, 2025 column; Recycling; Substitutes
media: []
documents:
  - title: 'Concept Alloys: Tungsten-Rhenium Alloys data sheet (rev. 10-19-09)'
    type: datasheet
    url: https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/213/Tungsten_Rhenium_DS.pdf
    year: 2009
  - title: 'USGS Mineral Commodity Summaries 2026: Rhenium'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-rhenium.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: 'NASA TN D-4567: Yielding and Fracture in Tungsten and Tungsten-Rhenium Alloys (Raffo)'
    type: report
    url: https://ntrs.nasa.gov/api/citations/19680015005/downloads/19680015005.pdf
    year: 1968
  - title: 'NASA TN D-3483: Mechanical Properties of Dilute Tungsten-Rhenium Alloys'
    type: report
    url: https://ntrs.nasa.gov/api/citations/19660027741/downloads/19660027741.pdf
    year: 1966
  - title: 'AEC-NASA Tech Brief 68-10109: Tungsten-Rhenium Alloy Thermocouples Effective for High-Temperature Measurement'
    type: report
    url: https://ntrs.nasa.gov/api/citations/19680000109/downloads/19680000109.pdf
    year: 1968
  - title: 'NASA Tech Brief 66-10134: tungsten-rhenium gas-temperature probe'
    type: report
    url: https://ntrs.nasa.gov/api/citations/19660000133/downloads/19660000133.pdf
    year: 1966
  - title: 'Pratt and Whitney: design study of an in-pile nuclear thermionic space powerplant (NASA, Volume I)'
    type: report
    url: https://ntrs.nasa.gov/api/citations/19650001440/downloads/19650001440.pdf
    year: 1965
  - title: 'Angstrom Sciences: Rhenium safety data sheet (rev. 07/01/15)'
    type: sds
    url: https://angstromsciences.com/wp-content/uploads/files/SDS/Rhenium.pdf
    year: 2015
  - title: 'Fujifilm Wako: Tungsten, powder 99.9 percent safety data sheet'
    type: sds
    url: https://labchem-wako.fujifilm.com/sds/W01W0120-0344JGHEEN.pdf
  - title: 'Stanford Advanced Materials: Tungsten material safety data sheet (v2.0, rev. Sep 5, 2012)'
    type: sds
    url: https://www.sputtertargets.net/Public/pdf/tungsten-msds.pdf
    year: 2012
  - title: 'WebElements: Tungsten, key properties'
    type: database
    url: https://www.webelements.com/tungsten/
  - title: 'WebElements: Rhenium, key properties'
    type: database
    url: https://www.webelements.com/rhenium/
gaps:
  - 'Thermal expansion of W25/26Re (2.9 x 10-6 in/in/°F at 68 °F, Concept Alloys data sheet) was removed: the value did not match the printed text when verify-values checked it, so it is not used until the table row is checked by hand.'
  - No tungsten-rhenium grade in the set has a standard designation read in this run. ASTM E230 temperature tables and the IEC 60584 type C and D pairs are named by the data sheet, but no UNS, EN, AISI or ASTM grade code for W-Re was printed on a page we read, so identity.designations is empty.
  - PubChem GHS records for rhenium and tungsten could not be read (the site returned a browser verification page), so the PubChem hazard data used for tungsten in the tungsten profile were not repeated here. Hazards rest on three SDSs and the Angstrom rhenium SDS.
  - Springer 2021 paper on additively manufactured W-Re (relative density up to 97.6 percent for W-25Re) redirected to a login page and was not read.
  - Stanford Advanced Materials powder page gives a melting point of 3350 °C for W-5Re powder; it was seen only in a search snippet and is not used.
  - Thermocouple EMF tables (ASTM E230, IEC 60584-1) were not read, so no EMF value is given. The Goodfellow thin-film thermocouple figure (165.5 uV/°C at 700 °C) is a thin-film device, not a bulk alloy, and is not used.
  - Goodfellow gives thermal conductivity 130 to 180 W/m K at room temperature for the W-Re system without naming a grade, so it is not used as a property.
  - Crustal abundance of tungsten and rhenium was not read in a source we could open.
  - Whether tungsten is on the USGS 2025 critical minerals list was not stated in the USGS tungsten summary. Neither metal was checked against the EU critical raw materials list.
  - Secondary tungsten quantity for 2025 is withheld in the USGS summary, so tungsten recycling share is not given.
  - Corrosion in acids and aqueous media for W-Re has no source we read; only the qualitative oxidation statements above were found.
  - The Goodfellow page says W-Re oxidation resistance is excellent; the Concept Alloys data sheet says rapid oxidation. The conflict is recorded in corrosion and not resolved.
  - The alloy composition by weight is inferred from the grade names, which the NASA reports use (26 percent rhenium alloy, 25 percent rhenium alloy). No source we read defines the grade by weight or atomic percent in one line.
  - The Pratt and Whitney scan is OCR text and the cathode-tube statement comes from the scanned report; no flight or space-environment use of W-Re was found.
  - The Plansee page gives no rhenium percentage for focal-track alloys.
  - The Concept Alloys data sheet is dated rev. 10-19-09 and gives no test standard for density or tensile values beyond the note that its products conform to ASTM E696 and ASTM E988.
  - The ductile-brittle transition temperature has no canonical property name in spores/property-canon.yaml; it is entered as ductile_brittle_transition_temperature and needs a canonical name before import.
sources:
  webel-w:
    title: 'WebElements: Tungsten, key properties'
    id: WebElements, tungsten main page
    url: https://www.webelements.com/tungsten/
    kind: database
    license: WebElements terms of use (cited, not reproduced)
  webel-re:
    title: 'WebElements: Rhenium, key properties'
    id: WebElements, rhenium main page
    url: https://www.webelements.com/rhenium/
    kind: database
    license: WebElements terms of use (cited, not reproduced)
  concept-wre-ds:
    title: 'Concept Alloys: Tungsten-Rhenium Alloys data sheet (rev. 10-19-09)'
    id: Concept Alloys tungsten-rhenium data sheet, hosted by DigiKey
    url: https://mm.digikey.com/Volume0/opasdata/d220001/medias/docus/213/Tungsten_Rhenium_DS.pdf
    year: 2009
    kind: datasheet
    license: supplier data sheet (cited, not reproduced)
  usgs-mcs2026-rhenium:
    title: 'Mineral Commodity Summaries 2026: Rhenium'
    id: USGS MCS 2026, rhenium
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-rhenium.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  usgs-mcs2026-tungsten:
    title: 'Mineral Commodity Summaries 2026: Tungsten'
    id: USGS MCS 2026, tungsten
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-tungsten.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  raffo-tnd4567:
    title: Yielding and Fracture in Tungsten and Tungsten-Rhenium Alloys (NASA TN D-4567, Raffo)
    id: NASA NTRS 19680015005
    url: https://ntrs.nasa.gov/api/citations/19680015005/downloads/19680015005.pdf
    year: 1968
    kind: report
    license: public domain (NASA)
  klopp-tnd3483:
    title: Mechanical Properties of Dilute Tungsten-Rhenium Alloys (NASA TN D-3483)
    id: NASA NTRS 19660027741, accession N66-37031
    url: https://ntrs.nasa.gov/api/citations/19660027741/downloads/19660027741.pdf
    year: 1966
    kind: report
    license: public domain (NASA)
  nasa-tb-68-10109:
    title: 'AEC-NASA Tech Brief 68-10109: Tungsten-Rhenium Alloy Thermocouples Effective for High-Temperature Measurement'
    id: NASA NTRS 19680000109, brief 68-10109
    url: https://ntrs.nasa.gov/api/citations/19680000109/downloads/19680000109.pdf
    year: 1968
    kind: report
    license: public domain (NASA)
  nasa-tb-66-10134:
    title: 'NASA Tech Brief 66-10134: tungsten-rhenium gas-temperature probe'
    id: NASA NTRS 19660000133, brief 66-10134
    url: https://ntrs.nasa.gov/api/citations/19660000133/downloads/19660000133.pdf
    year: 1966
    kind: report
    license: public domain (NASA)
  pw-thermionic-1965:
    title: Design study of a high power in-pile nuclear thermionic space powerplant (Pratt and Whitney, prepared for NASA, Volume I)
    id: NASA NTRS 19650001440 (OCR scan)
    url: https://ntrs.nasa.gov/api/citations/19650001440/downloads/19650001440.pdf
    year: 1965
    kind: report
    license: public domain (NASA)
  plansee-xray:
    title: 'Plansee: Components for generating X-rays'
    id: Plansee product page
    url: https://plansee.com/en/products/components-for-generating-x-rays.html
    kind: web
    license: supplier web page (cited, not reproduced)
  goodfellow-wre:
    title: 'Goodfellow: Tungsten/Rhenium alloy material information'
    id: Goodfellow product information page
    url: https://www.goodfellow.com/usa/resources/tungsten-rhenium-alloy-material-information/
    kind: web
    license: supplier web page (cited, not reproduced)
  angstrom-re-sds:
    title: 'Angstrom Sciences: Rhenium safety data sheet'
    id: CAS 7440-15-5; revision 07/01/15
    url: https://angstromsciences.com/wp-content/uploads/files/SDS/Rhenium.pdf
    year: 2015
    kind: datasheet
    license: supplier document (cited, not reproduced)
  wako-w-sds:
    title: 'Fujifilm Wako: Tungsten, powder 99.9 percent safety data sheet'
    id: W01W0120-0344 JGHEEN
    url: https://labchem-wako.fujifilm.com/sds/W01W0120-0344JGHEEN.pdf
    kind: datasheet
    license: supplier document (cited, not reproduced)
  sam-w-msds:
    title: 'Stanford Advanced Materials: Tungsten material safety data sheet'
    id: SAM tungsten MSDS v2.0, revised 2012-09-05
    url: https://www.sputtertargets.net/Public/pdf/tungsten-msds.pdf
    year: 2012
    kind: datasheet
    license: supplier document (cited, not reproduced)
license: CC-BY-4.0
updated: '2026-10-26'
review:
  status: draft
  method: assistant
  checked_values: 19
  unreachable: 4
  caveats: 4
  note: 'Read by an AI assistant on 2026-10-26: 20 property values read from the Concept Alloys data sheet, two NASA technical notes, and WebElements; tech briefs and USGS used for uses and supply. Springer 2021 paper and PubChem records could not be opened, and the Goodfellow and Plansee pages were read for qualitative statements only.'
story:
  recipe:
    line: W-Re alloys are tungsten with rhenium added. The grade number is the rhenium content in the name (NASA reports describe a 26 percent rhenium alloy and a 25 percent rhenium alloy). Tungsten has an atomic weight of 183.84 and rhenium 186.207 (WebElements).
    parts:
      - name: Tungsten
        symbol: W
        role: The matrix of the alloy. Tungsten gives the high melting point, and rhenium makes the metal more ductile at low temperature.
      - name: Rhenium
        symbol: Re
        role: The alloying addition, typically 3 to 26 percent in the grades in the data sheet. It lowers the ductile-brittle transition and improves ductility after recrystallization.
  risk_groups:
    - title: For people
      level: 0
      verdict: Powder is the hazard
      lead: The bulk metal has few notified hazards. Fine powder of the component metals does carry fire and irritation hazards.
      points:
        - label: Rhenium powder
          line: The Angstrom Sciences rhenium SDS classes the metal as a flammable solid (H228) and says it is hazardous as a powder only.
        - label: Tungsten powder
          line: The Fujifilm Wako tungsten powder SDS gives H320 (eye irritation) and H335 (respiratory irritation). The Stanford Advanced Materials SDS says most studies show tungsten to be toxicologically inert, but dust can irritate the nose, throat, skin and eyes.
    - title: At high temperature
      lead: The main hazard in use is oxidation, not toxicity.
      points:
        - label: In air
          line: The Concept Alloys data sheet says both W-Re combinations oxidise rapidly at high temperature and are not recommended for oxidising environments.
  why: Tungsten-rhenium alloys keep most of tungsten's high melting point and density while gaining the ductility that pure tungsten lacks at low temperature. NASA found that dilute rhenium additions lower the ductile-brittle transition of tungsten, and the data sheet says the W5Re and W26Re thermoelements keep good room-temperature ductility after heating above 3000 °F. That makes them usable as thermocouple legs, as X-ray target tracks and as cathode tubes in nuclear-space design studies.
  uses:
    - where: Thermocouples for very high temperatures
      line: NASA Tech Brief 68-10109 reports W-Re thermocouples effective for measurement above 2920 °C, using a W+5Re leg because pure tungsten was too brittle.
    - where: Gas-temperature probes
      line: NASA Tech Brief 66-10134 describes a W-Re probe for a flowing gas at up to 4500 °F in a hazardous radiation environment.
    - where: Nuclear-space design study
      line: A Pratt and Whitney design study for an in-pile nuclear thermionic space powerplant considered W-25Re for the cathode tube. It was not flown.
    - where: Rotating X-ray anodes
      line: Plansee says its rotating anodes have focal tracks of tungsten-rhenium alloys on molybdenum-alloy bodies. The page gives no rhenium percentage.
  can_do:
    - label: Melting point
      benchmark: melting_point
      value: 3350 °C
      line: The Concept Alloys data sheet gives 3350 °C for W5Re and 3120 °C for the W25/26Re column.
    - label: Density
      benchmark: density
      value: 19.4 g/cm3
      line: The data sheet gives 19.4 g/cm3 for W5Re and 19.7 g/cm3 for W25/26Re, against 19.3 g/cm3 for unalloyed tungsten in the same table.
    - label: Tensile strength at room temperature
      benchmark: ultimate_tensile_strength
      value: 220 x 10^3 psi
      line: Annealed W5Re gives 220 x 10^3 psi at 68 °F and 26 x 10^3 psi at 3632 °F, according to the data sheet.
    - label: Ductile-brittle transition
      benchmark: ductile_brittle_transition_temperature
      value: 350 K
      line: NASA TN D-4567 gives 350 K for arc-melted W-25Re against 490 K for unalloyed recrystallized tungsten.
  compare: Among the refractory metals, W-Re has a melting point near that of pure tungsten but better low-temperature ductility. The data sheet gives 3350 °C for W5Re and 3120 °C for the W25/26Re column, and densities of 19.4 and 19.7 g/cm3. The compare rows name the properties to set against other refractory metals; the values above are the only W-Re figures read in this run.
  compare_rows:
    - scope: material
      label: Melting point
      benchmark: melting_point
    - scope: material
      label: Density
      benchmark: density
    - scope: material
      label: Tensile strength
      benchmark: ultimate_tensile_strength
  handling:
    - Use it at high temperature only in reducing, inert or vacuum conditions. Oxidation in air is rapid, according to the data sheet.
    - Keep powder away from strong oxidisers and acids. Acids can release flammable hydrogen from tungsten powder.
    - Keep dust from building up, and keep ignition sources away from it.
  good_for:
    - Thermocouples for very high temperatures, where the W-5Re against W-26Re pair has the widest industry acceptance.
    - Rotating X-ray anode focal tracks, which need a dense, high-melting surface.
  watch_out:
    - Rapid oxidation at high temperature. The data sheet does not recommend these alloys in oxidising environments.
    - Brittle when cold below the transition temperature. Pure tungsten is brittle, and W-Re alloys reduce but do not remove this.
    - 'Rhenium is expensive and supply is concentrated: about 37 percent of 2025 world mine output came from Chile, and the rhenium price rose sharply in 2025 (USGS).'
  verdict: W-Re is the choice for very high-temperature thermocouples and X-ray tracks where tungsten alone is too brittle and the atmosphere is controlled. Its melting point and density are well documented; its oxidation limits and corrosion in acids are not, so it needs a controlled atmosphere in any design.