{
  "spore": "profile",
  "id": "rhenium",
  "spore_version": "0.2",
  "family": "refractory-metals",
  "name": "Rhenium",
  "abbreviation": "Re",
  "role": "high-temperature structural metal for thruster chambers and superalloys",
  "category": "metals",
  "type": "refractory-metals",
  "summary": "Rhenium is the element Re, a pure refractory metal with a density of 21.02 g/cm3 and a melting point of 3186 °C. Its main use is as an alloying addition to nickel-base superalloys for jet-engine turbine parts (about 80 % of end use in 2025, per USGS). It is also the structural substrate of iridium-coated rhenium rocket thrust chambers that NASA-funded tests ran at about 2200 °C with a specific impulse of 310 s for a 22 N class thruster. Uncoated rhenium oxidises in air above about 300 °C, so the flight-tested chambers depend on an iridium coating.\n",
  "best_for": "Structures that must hold strength above 2000 °C: iridium-coated rhenium thrust chambers tested up to about 2200 °C",
  "weakest_at": "Oxidation in air or oxygen-rich gas above about 300 °C, which makes uncoated rhenium unusable without a protective coating",
  "identity": {
    "formula": "Re (element, atomic number 75); commercial grade 99.99 % (4N) rhenium, Goodfellow",
    "cas": "7440-15-5",
    "designations": [],
    "source": "pubchem-re",
    "where": "PubChem compound record for rhenium (CID 23947), Names and Identifiers section: CAS 7440-15-5; EC number 231-124-5 in the same record."
  },
  "tags": {
    "environments": [],
    "stresses": [],
    "applications": [
      "propulsion-and-tanks"
    ]
  },
  "properties": [
    {
      "benchmark": "density",
      "label": "Density at 20 °C",
      "value": 21.02,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "form": "pure rhenium metal",
        "temperature": "20 °C"
      },
      "method": "Value printed on a supplier product page",
      "status": "ground",
      "source": "goodfellow-re",
      "where": "General properties table, row Density",
      "source_detail": {
        "title": "Goodfellow Metals, Rhenium Re 99.99 % (4N), product information page",
        "url": "https://www.goodfellow.com/usa/material/metals/rhenium",
        "kind": "datasheet",
        "license": "Supplier product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Melting point",
      "value": 3186,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "form": "pure rhenium metal",
        "unit_in_source": "3,186 °C (3,459 K)"
      },
      "method": "Value printed on a supplier product page",
      "status": "ground",
      "source": "goodfellow-re",
      "where": "General properties table, row Melting point",
      "source_detail": {
        "title": "Goodfellow Metals, Rhenium Re 99.99 % (4N), product information page",
        "url": "https://www.goodfellow.com/usa/material/metals/rhenium",
        "kind": "datasheet",
        "license": "Supplier product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Melting point (university database, kelvin as printed)",
      "value": 3459,
      "bound": "exact",
      "unit": "K",
      "scope": "material",
      "conditions": {
        "form": "rhenium element",
        "unit_in_source": "3459 K (3186 °C, 5767 °F)"
      },
      "method": "Value printed in a university element database entry",
      "status": "ground",
      "source": "utu-re",
      "where": "Numeric properties list, Melting point row",
      "source_detail": {
        "title": "University of Turku, element database entry for rhenium",
        "url": "https://imc.utu.fi/elements/rhenium.php",
        "kind": "database",
        "license": "University web page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "boiling_point",
      "label": "Boiling point",
      "value": 5596,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "form": "pure rhenium metal",
        "unit_in_source": "5,596 °C (5,869 K)"
      },
      "method": "Value printed on a supplier product page",
      "status": "ground",
      "source": "goodfellow-re",
      "where": "General properties table, row Boiling point",
      "source_detail": {
        "title": "Goodfellow Metals, Rhenium Re 99.99 % (4N), product information page",
        "url": "https://www.goodfellow.com/usa/material/metals/rhenium",
        "kind": "datasheet",
        "license": "Supplier product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity at 25 °C",
      "value": 48,
      "bound": "exact",
      "unit": "W/m·K",
      "scope": "material",
      "conditions": {
        "form": "pure rhenium metal",
        "temperature": "25 °C"
      },
      "method": "Value printed on a supplier product page",
      "status": "ground",
      "source": "goodfellow-re",
      "where": "General properties table, row Thermal conductivity",
      "source_detail": {
        "title": "Goodfellow Metals, Rhenium Re 99.99 % (4N), product information page",
        "url": "https://www.goodfellow.com/usa/material/metals/rhenium",
        "kind": "datasheet",
        "license": "Supplier product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "electrical_resistivity",
      "label": "Electrical resistivity at 20 °C",
      "value": 196,
      "bound": "exact",
      "unit": "nΩ·m",
      "scope": "material",
      "conditions": {
        "form": "pure rhenium metal",
        "temperature": "20 °C"
      },
      "method": "Value printed on a supplier product page",
      "status": "ground",
      "source": "goodfellow-re",
      "where": "General properties table, row Electrical resistivity",
      "source_detail": {
        "title": "Goodfellow Metals, Rhenium Re 99.99 % (4N), product information page",
        "url": "https://www.goodfellow.com/usa/material/metals/rhenium",
        "kind": "datasheet",
        "license": "Supplier product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Young's modulus",
      "value": 460,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "form": "rhenium metal",
        "note_in_source": "some sources list 360 to 460 GPa depending on crystallographic orientation"
      },
      "method": "Value printed on a supplier product page",
      "status": "ground",
      "source": "goodfellow-re",
      "where": "Mechanical properties table, row Young's modulus",
      "source_detail": {
        "title": "Goodfellow Metals, Rhenium Re 99.99 % (4N), product information page",
        "url": "https://www.goodfellow.com/usa/material/metals/rhenium",
        "kind": "datasheet",
        "license": "Supplier product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "poissons_ratio",
      "label": "Poisson's ratio",
      "value": 0.3,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "form": "rhenium metal"
      },
      "method": "Value printed on a supplier product page",
      "status": "ground",
      "source": "goodfellow-re",
      "where": "Mechanical properties table, row Poisson's ratio",
      "source_detail": {
        "title": "Goodfellow Metals, Rhenium Re 99.99 % (4N), product information page",
        "url": "https://www.goodfellow.com/usa/material/metals/rhenium",
        "kind": "datasheet",
        "license": "Supplier product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "vickers_hardness",
      "label": "Vickers hardness, annealed (custom name, not in property canon)",
      "value": 2450,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "annealed rhenium",
        "approximate_in_source": "printed as about 2,450 MPa Vickers"
      },
      "method": "Value printed on a supplier product page; the page also gives Mohs hardness of about 7",
      "status": "ground",
      "source": "goodfellow-re",
      "where": "Mechanical properties table, row Hardness",
      "source_detail": {
        "title": "Goodfellow Metals, Rhenium Re 99.99 % (4N), product information page",
        "url": "https://www.goodfellow.com/usa/material/metals/rhenium",
        "kind": "datasheet",
        "license": "Supplier product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "yield_strength",
      "label": "Yield strength, annealed to cold-worked",
      "value": 200,
      "value_high": 500,
      "bound": "range",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "rhenium metal",
        "temper": "annealed to cold-worked"
      },
      "method": "Range printed on a supplier product page",
      "status": "ground",
      "source": "goodfellow-re",
      "where": "Mechanical properties table, row Yield strength",
      "source_detail": {
        "title": "Goodfellow Metals, Rhenium Re 99.99 % (4N), product information page",
        "url": "https://www.goodfellow.com/usa/material/metals/rhenium",
        "kind": "datasheet",
        "license": "Supplier product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength, annealed to cold-worked",
      "value": 400,
      "value_high": 700,
      "bound": "range",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "rhenium metal",
        "temper": "annealed to cold-worked"
      },
      "method": "Range printed on a supplier product page",
      "status": "ground",
      "source": "goodfellow-re",
      "where": "Mechanical properties table, row Tensile strength",
      "source_detail": {
        "title": "Goodfellow Metals, Rhenium Re 99.99 % (4N), product information page",
        "url": "https://www.goodfellow.com/usa/material/metals/rhenium",
        "kind": "datasheet",
        "license": "Supplier product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "elongation",
      "label": "Elongation at break, annealed",
      "value": 30,
      "value_high": 50,
      "bound": "range",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "form": "rhenium metal",
        "temper": "annealed"
      },
      "method": "Range printed on a supplier product page",
      "status": "ground",
      "source": "goodfellow-re",
      "where": "Mechanical properties table, row Elongation at break",
      "source_detail": {
        "title": "Goodfellow Metals, Rhenium Re 99.99 % (4N), product information page",
        "url": "https://www.goodfellow.com/usa/material/metals/rhenium",
        "kind": "datasheet",
        "license": "Supplier product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength at 1000 °C (approximate)",
      "value": 300,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "rhenium metal",
        "temperature": "1000 °C",
        "note_in_source": "printed as about 300 MPa at 1,000 °C"
      },
      "method": "Approximate value printed in the tensile-at-temperature note on a supplier product page",
      "status": "ground",
      "source": "goodfellow-re",
      "where": "Property notes, tensile strength at temperature (about 300 MPa at 1,000 °C)",
      "source_detail": {
        "title": "Goodfellow Metals, Rhenium Re 99.99 % (4N), product information page",
        "url": "https://www.goodfellow.com/usa/material/metals/rhenium",
        "kind": "datasheet",
        "license": "Supplier product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "vapor_pressure",
      "label": "Vapour pressure at 2000 °C (custom name, not in property canon)",
      "value": 1e-7,
      "bound": "exact",
      "unit": "Pa",
      "scope": "material",
      "conditions": {
        "form": "rhenium metal",
        "temperature": "2000 °C",
        "note_in_source": "printed as about 10^-7 Pa"
      },
      "method": "Approximate value printed on a supplier product page",
      "status": "ground",
      "source": "goodfellow-re",
      "where": "Property notes, vapour pressure at 2,000 °C",
      "source_detail": {
        "title": "Goodfellow Metals, Rhenium Re 99.99 % (4N), product information page",
        "url": "https://www.goodfellow.com/usa/material/metals/rhenium",
        "kind": "datasheet",
        "license": "Supplier product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "max_service_temp",
      "label": "Thrust chamber wall temperature with iridium-coated rhenium, NASA-funded thruster",
      "value": 2200,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "system": "iridium-coated rhenium thrust chamber",
        "test": "hot-fire and life tests, NTO/MMH and oxygen/hydrogen propellants",
        "unit_in_source": "2200° C"
      },
      "method": "Value stated as the operating temperature the material allows in a NASA technical memorandum abstract",
      "status": "ground",
      "source": "nasa-tm-105348",
      "where": "Abstract, sentence beginning \"This material increases the operating temperature of thrusters\"",
      "source_detail": {
        "title": "Schneider, High Temperature Thruster Technology for Spacecraft Propulsion (NASA TM 105348, IAF-91-254)",
        "id": "NTRS 19920005907",
        "url": "https://ntrs.nasa.gov/api/citations/19920005907/downloads/19920005907.pdf",
        "year": 1991,
        "kind": "paper",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "specific_impulse",
      "label": "Specific impulse of 22 N NTO/MMH thruster with iridium-lined rhenium chamber (custom name, not in property canon)",
      "value": 310,
      "bound": "exact",
      "unit": "s",
      "scope": "material",
      "conditions": {
        "system": "22 N (5 lbf) class bipropellant thruster, 150:1 area ratio nozzle",
        "propellant": "NTO/MMH",
        "test": "hot-fire test, ground"
      },
      "method": "Measured value printed in a NASA contract final report abstract",
      "status": "ground",
      "source": "nasa-cr-185233",
      "where": "Abstract, sentence \"A specific impulse of 310 seconds was measured\"",
      "source_detail": {
        "title": "Aerojet, High-Temperature, Oxidation-Resistant Thruster Research, final report on NASA contract NAS 3-24643 (NASA CR 185233, February 1990)",
        "id": "NTRS 19910006750",
        "url": "https://ntrs.nasa.gov/api/citations/19910006750/downloads/19910006750.pdf",
        "year": 1990,
        "kind": "report",
        "license": "public domain (NASA)"
      }
    },
    {
      "benchmark": "specific_impulse_gain",
      "label": "Specific impulse gain over silicide-coated niobium chambers (custom name, not in property canon)",
      "value": 20,
      "value_high": 25,
      "bound": "range",
      "unit": "s",
      "scope": "material",
      "conditions": {
        "system": "22 N class thrusters, iridium-coated rhenium against niobium chambers",
        "test": "steady-state firing, ground"
      },
      "method": "Range printed in a NASA technical memorandum abstract",
      "status": "ground",
      "source": "nasa-tm-105348",
      "where": "Abstract, sentence \"Stationkeeping class 22 N engines ... 20 to 25 seconds higher than niobium\"",
      "source_detail": {
        "title": "Schneider, High Temperature Thruster Technology for Spacecraft Propulsion (NASA TM 105348, IAF-91-254)",
        "id": "NTRS 19920005907",
        "url": "https://ntrs.nasa.gov/api/citations/19920005907/downloads/19920005907.pdf",
        "year": 1991,
        "kind": "paper",
        "license": "public domain (NASA)"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Air or oxygen-containing gas above about 300 °C",
      "headline": "Uncoated rhenium oxidises to a volatile oxide above about 300 °C, so it needs a protective coating in hot oxygen.",
      "effect": "Goodfellow says rhenium forms volatile Re2O7 above about 300 °C in air. This is why the NASA thrusters use an iridium coating.",
      "rating": "severe",
      "conditions": {
        "form": "pure rhenium metal",
        "temperature": "above about 300 °C",
        "atmosphere": "air"
      },
      "source": "goodfellow-re",
      "where": "Chemical and oxidation property notes, high-temperature oxidation entry"
    },
    {
      "environment": "NTO/MMH rocket combustion gas at 2100 to 2200 °C",
      "headline": "An iridium coating protects rhenium chambers from hot NTO/MMH combustion gas for at least 15 hours.",
      "effect": "Ultramet's report states that iridium protects rhenium from NTO/MMH combustion gases at 2100 to 2200 °C (3800 to 4000 °F) for at least 15 hours. One iridium-lined rhenium nozzle survived over 4000 cycles and 15 hours of continuous operation with no measurable change in throat dimensions.",
      "rating": "moderate",
      "conditions": {
        "coating": "iridium on rhenium, CVD",
        "environment": "NTO/MMH combustion gas, 22 N thrusters",
        "duration": "at least 15 hours"
      },
      "source": "nasa-tm-101309",
      "where": "Concluding remarks; text on the 22 N thruster hot-fire tests"
    },
    {
      "environment": "Iridium-coated rhenium at high temperature in vacuum or oxygen",
      "headline": "Rhenium diffuses into the iridium coating, which will eventually lead to coating failure.",
      "effect": "NASA contract report: diffusion of rhenium into iridium will eventually lead to coating failure and subsequent exposure. Above 20 atomic percent rhenium the iridium-rhenium alloy readily oxidised in every environment tested.",
      "rating": "moderate",
      "conditions": {
        "test": "diffusion couples held at 4000 °F (2200 °C) in vacuum, and oxidation tests of Ir-Re alloys",
        "note": "from the NASA Phase II study"
      },
      "source": "nasa-cr-185233",
      "where": "Results text on Ir/Re diffusion couples and Ir-Re alloy oxidation (Figure 3 discussion)"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "PubChem, from the ECHA C&L Inventory: of 393 company reports, 137 said rhenium does not meet GHS criteria and 256 gave hazard codes. Where codes were given, H228 flammable solid was reported in 63.9 %. Signal word Danger. Precautionary codes printed: P210, P240, P241, P280, P370+P378.",
        "ghs": [
          "H228"
        ],
        "source": "pubchem-re",
        "where": "GHS Classification section, notifications summary and hazard codes"
      },
      {
        "text": "PubChem hazards summary: the powdered form is flammable. It also notes no reported toxicity in workers handling perrhenic acid or ammonium perrhenate, citing Hawley and Ullmann.",
        "ghs": [],
        "source": "pubchem-re",
        "where": "Other Safety Information, Hazards Summary entry"
      },
      {
        "text": "The Goodfellow product page prints UN number UN3089 for the metal powder form of rhenium.",
        "ghs": [],
        "source": "goodfellow-re",
        "where": "Identifiers and designation codes section, UN number entry"
      }
    ],
    "failure_risks": [
      {
        "mode": "Oxidation of uncoated rhenium in hot air or oxygen",
        "trigger": "Uncoated rhenium exposed to air above about 300 °C",
        "consequence": "Volatile Re2O7 forms, so the metal is lost from the surface. Goodfellow gives no rate.",
        "severity": "high",
        "source": "goodfellow-re",
        "where": "Chemical and oxidation property notes, high-temperature oxidation entry"
      },
      {
        "mode": "Interdiffusion of rhenium into an iridium coating",
        "trigger": "Iridium-coated rhenium held at high temperature for a long time",
        "consequence": "The NASA contract report says the diffusion will eventually lead to coating failure and exposure of the rhenium to combustion gas.",
        "severity": "moderate",
        "source": "nasa-cr-185233",
        "where": "Results text on Ir/Re diffusion couples"
      },
      {
        "mode": "Oxidation of iridium-rhenium alloys with high rhenium content",
        "trigger": "Rhenium above 20 atomic percent in an iridium-rhenium alloy",
        "consequence": "The alloy readily oxidised in all environments tested, so the coating must stay near pure iridium.",
        "severity": "moderate",
        "source": "nasa-cr-185233",
        "where": "Results text, Figure 3 discussion of Ir/Re oxidation rate"
      }
    ],
    "side_effects": [
      {
        "text": "The USGS gives a 2025 estimated average price of 2,600 US dollars per kilogram for rhenium metal at 99.99 % purity, a 90 % rise on 2024. Industry sources said recyclers need prices above 3,000 dollars per kilogram to offset processing costs.",
        "affects": "Cost of components and of recycling superalloy scrap",
        "source": "usgs-mcs2026-rhenium",
        "where": "Salient Statistics, price row Metal, 99.99% pure; Events, Trends, and Issues"
      }
    ],
    "handling": [
      {
        "text": "Goodfellow says rhenium requires diamond or CBN grinding wheels for machining.",
        "source": "goodfellow-re",
        "where": "Hardness property note"
      },
      {
        "text": "The metal powder is flammable (H228 in PubChem). The safety codes are listed in the PubChem record. Handle as a flammable solid in powder form.",
        "source": "pubchem-re",
        "where": "GHS Classification section"
      }
    ],
    "mitigations": [
      {
        "text": "NASA thrusters use an iridium coating, applied by CVD over a rhenium substrate, to resist oxidation in the combustion gas.",
        "source": "nasa-tm-101309",
        "where": "Introduction, paragraph on what rhenium lacks and the iridium coating"
      }
    ]
  },
  "uses": [
    {
      "application": "propulsion-and-tanks",
      "device": "Iridium-lined rhenium thrust chamber for a 22 N (5 lbf) bipropellant thruster",
      "example": "A 22 N class NTO/MMH thruster with an iridium-lined rhenium chamber and a 150:1 nozzle reached 310 s specific impulse in a hot-fire test. NASA lists these 22 N chambers for orbit insertion, stationkeeping or attitude control.",
      "source": "nasa-cr-185233",
      "where": "Abstract (310 s); see nasa-tm-101309 Introduction for the list of spacecraft functions"
    },
    {
      "application": "propulsion-and-tanks",
      "device": "Nickel-base superalloy parts for high-temperature turbine engine components",
      "example": "USGS estimates superalloys took about 80 % of rhenium end use in 2025. Rhenium improves the high-temperature (above 1000 °C) strength of some nickel-base superalloys.",
      "source": "usgs-mcs2026-rhenium",
      "where": "Domestic Production and Use paragraph, first sentences"
    },
    {
      "application": "electronics-and-chips",
      "device": "Electrical contacts, thermocouples and electron tubes",
      "example": "USGS lists rhenium alloys among uses in electrical contacts, electron tubes and targets, thermocouples, semiconductors and vacuum tubes. Tungsten-rhenium thermocouples are not sourced here.",
      "source": "usgs-mcs2026-rhenium",
      "where": "Domestic Production and Use paragraph, list of other applications"
    }
  ],
  "supply": [
    {
      "subject": "Rhenium (mine production, rhenium content, 2025)",
      "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": "U.S. Final 2025 List of Critical Minerals (rhenium added; USGS Mineral Commodity Summaries 2026)",
          "listed": true
        }
      ],
      "recycling": "USGS: nickel-base superalloy scrap and scrapped turbine blades are recycled hydrometallurgically to make rhenium metal for new superalloy melts. Industry sources estimate global secondary production at 20,000 to 25,000 kg in 2025, excluding rhenium recovered in a closed loop from spent catalysts.",
      "substitutes": [
        "USGS: iridium and tin catalysts have been commercially successful in place of platinum-rhenium; cobalt and tungsten for coatings on copper X-ray targets; rhodium and rhodium-iridium for high-temperature thermocouples; tungsten and platinum-ruthenium for electrical contacts; tungsten and tantalum for electron emitters."
      ],
      "source": "usgs-mcs2026-rhenium",
      "where": "World Mine Production and Reserves table, 2025 column (world total 81,000 kg; shares calculated by Space Mushroom from Chile 30,000, China 20,000, Poland 10,000, United States 9,800, Uzbekistan 7,000 kg); Recycling; Substitutes; Events, Trends, and Issues"
    },
    {
      "subject": "Rhenium imports to the United States (rhenium metal, 2021 to 2024)",
      "producers": [
        {
          "country": "Chile",
          "share_percent": 38,
          "year": 2024
        },
        {
          "country": "Canada",
          "share_percent": 28,
          "year": 2024
        },
        {
          "country": "Germany",
          "share_percent": 21,
          "year": 2024
        },
        {
          "country": "Poland",
          "share_percent": 11,
          "year": 2024
        }
      ],
      "critical_lists": [],
      "recycling": "USGS: United States imports for consumption of unwrought rhenium and powders were 23,000 kg in 2025e, against 12,600 kg in 2024. Net import reliance was 75 % of apparent consumption in 2025e.",
      "substitutes": [],
      "source": "usgs-mcs2026-rhenium",
      "where": "Import Sources (2021-24) paragraph, rhenium metal list; Salient Statistics, Imports for consumption row"
    }
  ],
  "media": [],
  "documents": [
    {
      "title": "Goodfellow Metals, Rhenium (Re 99.99 %) product information page",
      "type": "datasheet",
      "url": "https://www.goodfellow.com/usa/material/metals/rhenium"
    },
    {
      "title": "University of Turku, Institute of Organic Chemistry and Element Database, Rhenium element page",
      "type": "database",
      "url": "https://imc.utu.fi/elements/rhenium.php"
    },
    {
      "title": "USGS Mineral Commodity Summaries 2026: Rhenium",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-rhenium.pdf",
      "year": 2026
    },
    {
      "title": "PubChem compound record for rhenium (CID 23947), including ECHA C&L Inventory classification",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/Rhenium"
    },
    {
      "title": "Aerojet, Contract NAS 3-24643 Final Report: High-Temperature, Oxidation-Resistant Thruster Research, NASA CR 185233",
      "type": "report",
      "url": "https://ntrs.nasa.gov/api/citations/19910006750/downloads/19910006750.pdf",
      "year": 1990
    },
    {
      "title": "Schneider, High Temperature Thruster Technology for Spacecraft Propulsion, NASA TM 105348 (IAF-91-254)",
      "type": "paper",
      "url": "https://ntrs.nasa.gov/api/citations/19920005907/downloads/19920005907.pdf",
      "year": 1991
    },
    {
      "title": "Harding and Kazaroff, Iridium-Coated Rhenium Thrusters by CVD, NASA TM 101309",
      "type": "paper",
      "url": "https://ntrs.nasa.gov/api/citations/19880020490/downloads/19880020490.pdf",
      "year": 1988
    },
    {
      "title": "Wikipedia: Rhenium (composition, history and production method only)",
      "type": "database",
      "url": "https://en.wikipedia.org/wiki/Rhenium"
    }
  ],
  "gaps": [
    "Designations: no UNS, ASTM, AISI, EN, DIN, JIS or trade-name code for pure rhenium was printed in any source fetched in this run. MatWeb's search returned no rhenium datasheet, the Rembar page returned 404, and the Plansee datasheet found covers only Mo-Re alloys. identity.designations is left empty.",
    "Coefficient of thermal expansion for pure rhenium was not found in a fetched page with a value; the Goodfellow page prints none and the Wikipedia figure was not used under the composition-only rule.",
    "Specific heat, heat of fusion and heat of vaporisation: not found in a fetched source with a condition.",
    "Electrical conductivity in % IACS and a room-temperature resistivity from a second source: not found.",
    "Radiation effects, cold welding and atomic-oxygen erosion of rhenium were not looked up.",
    "Corrosion rate in numbers (mass loss per hour in air or NTO/MMH gas): NASA reports give qualitative results and a 0.05 mil/h figure for pure iridium, not rhenium; no rhenium rate was recorded.",
    "The Plansee rhenium data sheet and the NIMS material data page were not reachable (404); the Rembar rhenium page was also not reachable (404).",
    "Thruster and coating values come from NASA contract reports and technical memoranda of 1988 to 1991 (ground tests); no flight result for an iridium-coated rhenium chamber was found.",
    "Tensile strength at 1000 °C, 1500 °C and 2500 °C is printed only as approximate values on the Goodfellow page; they are recorded at 1000 °C only.",
    "Vickers hardness, vapour pressure, specific impulse and specific impulse gain use custom property names because no canonical name exists for them in spores/property-canon.yaml.",
    "Supply shares are calculated by Space Mushroom from USGS tonnages (kg of rhenium content) and rounded to one decimal place.",
    "USGS 2025 mine production for Chile is an estimate from roaster residues (footnote 9); the value is printed as 30,000 kg.",
    "Rhenium ores and by-product recovery (roasting molybdenum concentrates) are described from the USGS text only; no smelting-process detail beyond the Wikipedia production method was read."
  ],
  "story": {
    "why": "Rhenium is a dense, very high-melting metal: 21.02 g/cm3 and 3186 °C. Its value comes from strength at high temperature. Alloyed into nickel-base superalloys it raises the strength of turbine parts above 1000 °C, and USGS puts that use at about 80 % of 2025 end use. It also forms the structural wall of thrust chambers that NASA-funded tests ran at about 2200 °C. Pure rhenium oxidises in air above about 300 °C, so the flight-candidate chambers carry an iridium coating.",
    "uses": [
      {
        "where": "Jet-engine superalloys",
        "line": "Rhenium improves the high-temperature strength of some nickel-base superalloys used in turbine engine parts. USGS estimates superalloys took about 80 % of end use in 2025."
      },
      {
        "where": "Thruster chambers",
        "line": "A 22 N class NTO/MMH thruster with an iridium-lined rhenium chamber reached 310 s specific impulse in a hot-fire test. NASA lists these chambers for orbit insertion, stationkeeping and attitude control."
      },
      {
        "where": "Electrical and thermal parts",
        "line": "USGS lists rhenium alloys in electrical contacts, electron tubes, thermocouples and vacuum tubes. Platinum-rhenium catalysts are a further use, about 15 % of 2025 end use."
      }
    ],
    "can_do": [
      {
        "label": "Stay strong when hot",
        "line": "Goodfellow gives an approximate tensile strength of 300 MPa at 1000 °C, about 150 MPa at 1500 °C and about 50 MPa at 2500 °C.",
        "benchmark": "ultimate_tensile_strength",
        "scope": "material",
        "value": "300 MPa at 1000 °C"
      },
      {
        "label": "Run hot",
        "line": "NASA reports that the iridium-coated rhenium chamber allows thruster operation up to 2200 °C.",
        "benchmark": "max_service_temp",
        "scope": "material",
        "value": "2200 °C"
      },
      {
        "label": "Heavy metal",
        "line": "Density is 21.02 g/cm3 at 20 °C, and the metal is hard, with a Vickers hardness of about 2450 MPa when annealed (Goodfellow).",
        "benchmark": "density",
        "scope": "material",
        "value": "21.02 g/cm3"
      },
      {
        "label": "Melting",
        "line": "The melting point is 3186 °C (3459 K) in both the supplier page and the University of Turku database.",
        "benchmark": "melting_point",
        "scope": "material",
        "value": "3186 °C"
      },
      {
        "label": "Thrust gain",
        "line": "Steady-state firing of the iridium-coated rhenium 22 N engines gave 20 to 25 s higher specific impulse than niobium chambers.",
        "benchmark": "specific_impulse_gain",
        "scope": "material",
        "value": "20 to 25 s"
      }
    ],
    "compare": "Against silicide-coated niobium thrust chambers, the baseline in the NASA reports, iridium-coated rhenium is rated to 2200 °C and gives 20 to 25 s more specific impulse. Rhenium is also costly: USGS gives 2,600 US dollars per kilogram for 99.99 % metal in 2025.",
    "compare_rows": [
      {
        "label": "Density",
        "benchmark": "density",
        "scope": "material"
      },
      {
        "label": "Melting point",
        "benchmark": "melting_point",
        "scope": "material"
      },
      {
        "label": "Thrust chamber max temperature",
        "benchmark": "max_service_temp",
        "scope": "material"
      }
    ],
    "handling": [
      "Use diamond or CBN wheels to machine it, as Goodfellow advises.",
      "Keep powder away from ignition sources, since the PubChem record gives it as a flammable solid.",
      "Specify the coating for hot oxygen service; uncoated rhenium oxidises above about 300 °C."
    ],
    "good_for": [
      "Strength above 2000 °C in thrust chambers, tested to 2200 °C with an iridium coating.",
      "Superalloy additions that raise high-temperature strength; superalloys took about 80 % of 2025 end use.",
      "Recycling: superalloy scrap and spent catalysts are recovered in a closed loop."
    ],
    "watch_out": [
      "Oxidation: uncoated rhenium loses material as volatile Re2O7 above about 300 °C in air.",
      "Coating life: rhenium diffuses into iridium and eventually causes coating failure, per NASA.",
      "Supply: the United States imported about 75 % of its apparent consumption in 2025e, and rhenium was added to the 2025 critical minerals list.",
      "Cost: 2,600 US dollars per kilogram for metal in 2025, up 90 % on 2024.",
      "No flight result for an iridium-coated rhenium chamber, no thermal expansion value and no radiation data were found for this profile."
    ],
    "verdict": "Rhenium is a dense, high-melting metal (21.02 g/cm3, 3186 °C) that keeps strength above 2000 °C, which is why it is used in superalloys and in iridium-coated rhenium thrust chambers tested to about 2200 °C. Uncoated, it oxidises above about 300 °C, the iridium coating wears by interdiffusion over time, and the metal is costly. The profile has no UNS designation and no thermal expansion value from a fetched source.",
    "recipe": {
      "line": "Rhenium is a single-element metal (Re, atomic number 75) (PubChem; Wikipedia). It is mostly recovered as a by-product of roasting molybdenum concentrates from porphyry copper-molybdenum deposits (USGS). Wikipedia states that the metal is made by reducing ammonium perrhenate with hydrogen at high temperature.",
      "parts": [
        {
          "name": "Rhenium",
          "symbol": "Re",
          "role": "The whole material. PubChem prints the molecular weight of the element as 186.207.",
          "atoms": 1,
          "atomic_weight": 186.207
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "The opened sources do not describe health effects of rhenium metal. The hazard entries are about the powder and a notification record.",
        "points": [
          {
            "label": "Rhenium as a substance",
            "line": "PubChem lists rhenium as a flammable solid (H228) with the signal word Danger in 63.9 % of the reports that gave codes. Of 393 reports, 137 said it does not meet GHS criteria."
          },
          {
            "label": "Powder",
            "line": "PubChem says the powdered form is flammable and that no toxicity has been reported in workers handling perrhenic acid or ammonium perrhenate."
          }
        ],
        "level": 1,
        "verdict": "Powder is flammable"
      },
      {
        "title": "If it fails",
        "lead": "The failure routes come from NASA ground tests and from the handbook-style property notes, not from flight data.",
        "points": [
          {
            "label": "Hot air",
            "line": "Uncoated rhenium forms volatile Re2O7 above about 300 °C in air, so it must be coated for hot oxygen service."
          },
          {
            "label": "Coating",
            "line": "NASA reports that rhenium diffuses into the iridium coating, which will eventually cause coating failure."
          }
        ]
      },
      {
        "title": "Handling and storage",
        "points": [
          {
            "label": "Machining",
            "line": "Goodfellow says rhenium needs diamond or CBN grinding wheels. Keep powder away from ignition sources as the PubChem codes advise."
          }
        ]
      }
    ]
  },
  "updated": "2026-10-26",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 17,
    "unreachable": 2,
    "caveats": 6,
    "note": "Values were read by an AI assistant on 2026-10-26 from the pages and PDFs named in each entry. Unreachable: NIMS and Rembar rhenium pages (HTTP 404). Caveats: the 2200 °C and 310 s values come from NASA ground-test reports; Young's modulus has a published range; the tensile values are ranges across temper; the hardness and vapour pressure are approximate; supply shares are calculated."
  },
  "sources": {
    "goodfellow-re": {
      "title": "Goodfellow Metals, Rhenium Re 99.99 % (4N), product information page",
      "url": "https://www.goodfellow.com/usa/material/metals/rhenium",
      "kind": "datasheet",
      "license": "Supplier product page (cited, not reproduced)"
    },
    "utu-re": {
      "title": "University of Turku, element database entry for rhenium",
      "url": "https://imc.utu.fi/elements/rhenium.php",
      "kind": "database",
      "license": "University web page (cited, not reproduced)"
    },
    "usgs-mcs2026-rhenium": {
      "title": "Mineral Commodity Summaries 2026, Rhenium (U.S. Geological Survey, February 2026)",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-rhenium.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    },
    "pubchem-re": {
      "title": "PubChem compound record: Rhenium (CID 23947), including ECHA C&L Inventory classification",
      "id": "CAS 7440-15-5, EC 231-124-5",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/Rhenium",
      "kind": "database",
      "license": "PubChem (NCBI), public domain; sections attributed to ECHA and others"
    },
    "nasa-cr-185233": {
      "title": "Aerojet, High-Temperature, Oxidation-Resistant Thruster Research, final report on NASA contract NAS 3-24643 (NASA CR 185233, February 1990)",
      "id": "NTRS 19910006750",
      "url": "https://ntrs.nasa.gov/api/citations/19910006750/downloads/19910006750.pdf",
      "year": 1990,
      "kind": "report",
      "license": "public domain (NASA)"
    },
    "nasa-tm-105348": {
      "title": "Schneider, High Temperature Thruster Technology for Spacecraft Propulsion (NASA TM 105348, IAF-91-254)",
      "id": "NTRS 19920005907",
      "url": "https://ntrs.nasa.gov/api/citations/19920005907/downloads/19920005907.pdf",
      "year": 1991,
      "kind": "paper",
      "license": "public domain (NASA)"
    },
    "nasa-tm-101309": {
      "title": "Harding and Kazaroff, Iridium-Coated Rhenium Thrusters by CVD (NASA TM 101309)",
      "id": "NTRS 19880020490",
      "url": "https://ntrs.nasa.gov/api/citations/19880020490/downloads/19880020490.pdf",
      "year": 1988,
      "kind": "paper",
      "license": "public domain (NASA)"
    },
    "wikipedia-re": {
      "title": "Rhenium (Wikipedia; composition, history and production method only)",
      "url": "https://en.wikipedia.org/wiki/Rhenium",
      "kind": "web",
      "license": "CC BY-SA 4.0 (cited, not reproduced)"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/rhenium/"
}