{
  "spore": "profile",
  "id": "haynes-188",
  "spore_version": "0.2",
  "family": "cobalt-alloys",
  "name": "Haynes 188",
  "abbreviation": "UNS R30188",
  "role": "high-temperature oxidation-resistant cobalt-nickel-chromium-tungsten wrought superalloy",
  "category": "metals",
  "type": "nickel-superalloys",
  "summary": "Haynes 188 (UNS R30188) is a wrought cobalt-base superalloy with a nominal composition of 39 % cobalt, 22 % nickel, 22 % chromium and 14 % tungsten. Haynes International rates it for long-term continuous exposure up to 2000 °F (1095 °C) in air and combustion gases. Its room-temperature tensile strength is 991 MPa in hot-rolled and solution-annealed plate, but it falls to 188 MPa at 1800 °F (982 °C), and the 1008 h flowing-air test at 2100 °F (1150 °C) shows 8.6 mils (218 µm) of metal loss.\n",
  "best_for": "Hot combustor and hot-structure parts in oxidising gas up to about 1095 °C, where stress stays low above about 982 °C",
  "weakest_at": "Strength above about 1800 °F (982 °C), and oxidation at 2100 °F (1150 °C), where metal loss is 8.6 mils (218 µm) after 1008 h, against 0.5 mil (13 µm) at 2000 °F",
  "identity": {
    "formula": "Cobalt-base alloy, nominal Co 39 (balance), Ni 22, Cr 22, W 14, Fe max 3, Mn max 1.25, Si 0.35, C 0.10, La 0.03, B max 0.015, in wt %",
    "designations": [
      {
        "system": "UNS",
        "code": "R30188",
        "source": "haynes-188-page",
        "where": "Principal Features text, HAYNES 188 alloy (UNS R30188)"
      },
      {
        "system": "Trade name",
        "code": "HAYNES 188",
        "source": "haynes-188-page",
        "where": "Page title, HAYNES 188 alloy"
      }
    ],
    "source": "haynes-188-page",
    "where": "Nominal Composition table (wt %); UNS R30188 in the Principal Features text"
  },
  "tags": {
    "environments": [],
    "stresses": [
      "extreme-heat",
      "thermal-cycling"
    ],
    "applications": [
      "propulsion-and-tanks",
      "thermal-control"
    ]
  },
  "properties": [
    {
      "benchmark": "density",
      "label": "Density at 22 °C (72 °F), Haynes 188",
      "value": 8.98,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "temperature": "22 °C (72 °F)",
        "unit_in_source": "0.324 lb/in3"
      },
      "method": "Value printed in a distributor technical data page",
      "status": "ground",
      "source": "hightempmetals-188",
      "where": "Physical Properties table, Density row, 72 °F / 22 °C",
      "source_detail": {
        "title": "HAYNES 188 technical data, High Temp Metals",
        "id": "Haynes 188 type analysis and technical data",
        "url": "https://www.hightempmetals.com/techdata/hitempHaynes188data.php",
        "kind": "datasheet",
        "license": "Distributor technical data page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Melting temperature range, Haynes 188 (manufacturer)",
      "value": 1315,
      "value_high": 1410,
      "bound": "range",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "basis": "melting temperature as printed by the manufacturer",
        "unit_in_source": "2400 to 2570 °F"
      },
      "method": "Range printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Physical Properties table, Melting Temperature row",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Incipient fusion temperature range, Haynes 188 (distributor)",
      "value": 1302,
      "value_high": 1330,
      "bound": "range",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "basis": "incipient fusion, the onset of melting, not the full melting range; differs from the manufacturer melting range and both are kept",
        "unit_in_source": "2375 to 2425 °F"
      },
      "method": "Range printed in a distributor technical data page",
      "status": "ground",
      "source": "hightempmetals-188",
      "where": "Physical Properties table, Incipient Fusion Temperature row, metric column",
      "source_detail": {
        "title": "HAYNES 188 technical data, High Temp Metals",
        "id": "Haynes 188 type analysis and technical data",
        "url": "https://www.hightempmetals.com/techdata/hitempHaynes188data.php",
        "kind": "datasheet",
        "license": "Distributor technical data page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "electrical_resistivity",
      "label": "Electrical resistivity at room temperature, Haynes 188",
      "value": 101,
      "bound": "exact",
      "unit": "µohm-cm",
      "scope": "material",
      "conditions": {
        "temperature": "RT, 21 °C (70 °F)",
        "unit_in_source": "39.6 µohm-in"
      },
      "method": "Value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Physical Properties table, Electrical Resistivity row, RT, metric column",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity at room temperature, Haynes 188",
      "value": 10.4,
      "bound": "exact",
      "unit": "W/m-°C",
      "scope": "material",
      "conditions": {
        "temperature": "RT",
        "unit_in_source": "72 Btu-in/ft2-hr-°F"
      },
      "method": "Value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Physical Properties table, Thermal Conductivity row, RT, metric column",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity at 1000 °C, Haynes 188",
      "value": 27.6,
      "bound": "exact",
      "unit": "W/m-°C",
      "scope": "material",
      "conditions": {
        "temperature": "1000 °C (2000 °F)",
        "unit_in_source": "204 Btu-in/ft2-hr-°F at 2000 °F"
      },
      "method": "Value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Physical Properties table, Thermal Conductivity row, 2000 °F (1000 °C) column",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "specific_heat",
      "label": "Specific heat at room temperature, Haynes 188",
      "value": 0.096,
      "bound": "exact",
      "unit": "Btu/lb-°F",
      "scope": "material",
      "conditions": {
        "temperature": "RT",
        "unit_in_source": "customary units only; the metric value printed beside it is garbled and not used"
      },
      "method": "Value printed in a manufacturer product page, customary units as printed",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Physical Properties table, Specific Heat row, RT, British column",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "cte",
      "label": "Mean coefficient of thermal expansion, 25 to 100 °C, Haynes 188",
      "value": 12.1,
      "bound": "exact",
      "unit": "µm/m-°C",
      "scope": "material",
      "conditions": {
        "temperature": "25 to 100 °C (mean)",
        "unit_in_source": "6.7 µin/in-°F for 75 to 200 °F"
      },
      "method": "Mean value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Physical Properties table, Mean Coefficient of Thermal Expansion row, 25-100 °C",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "cte",
      "label": "Mean coefficient of thermal expansion, 25 to 900 °C, Haynes 188",
      "value": 16,
      "bound": "exact",
      "unit": "µm/m-°C",
      "scope": "material",
      "conditions": {
        "temperature": "25 to 900 °C (mean)",
        "unit_in_source": "9.1 µin/in-°F for 75 to 1800 °F"
      },
      "method": "Mean value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Physical Properties table, Mean Coefficient of Thermal Expansion row, 75-1800 °F",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Dynamic modulus of elasticity at room temperature, Haynes 188",
      "value": 232,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "temperature": "RT",
        "unit_in_source": "33.7 x 10^6 psi"
      },
      "method": "Dynamic modulus printed in a manufacturer product page; a dynamic value, not a static tensile modulus",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Physical Properties table, Dynamic Modulus of Elasticity row, RT",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "yield_strength",
      "label": "Yield strength 0.2 % offset, hot-rolled and solution-annealed plate at room temperature",
      "value": 483,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "hot-rolled and solution-annealed plate",
        "temperature": "RT",
        "unit_in_source": "70.1 ksi"
      },
      "method": "Tensile test value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Tensile Properties table, Hot-Rolled and Solution-annealed Plate, RT row",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Ultimate tensile strength, hot-rolled and solution-annealed plate at room temperature",
      "value": 991,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "hot-rolled and solution-annealed plate",
        "temperature": "RT",
        "unit_in_source": "143.8 ksi"
      },
      "method": "Tensile test value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Tensile Properties table, Hot-Rolled and Solution-annealed Plate, RT row",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "elongation",
      "label": "Elongation, hot-rolled and solution-annealed plate at room temperature",
      "value": 50.6,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "form": "hot-rolled and solution-annealed plate",
        "temperature": "RT"
      },
      "method": "Tensile test value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Tensile Properties table, Hot-Rolled and Solution-annealed Plate, RT row, elongation column",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "yield_strength",
      "label": "Yield strength 0.2 % offset, bright annealed sheet at room temperature",
      "value": 464,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "bright annealed sheet, 0.029 to 0.050 in thick",
        "temperature": "RT (70 °F / 21 °C)",
        "unit_in_source": "67.3 ksi"
      },
      "method": "Average tensile value printed in a distributor technical data page",
      "status": "ground",
      "source": "hightempmetals-188",
      "where": "Average Tensile Data, Sheet table, row 70 °F (21 °C), yield column",
      "source_detail": {
        "title": "HAYNES 188 technical data, High Temp Metals",
        "id": "Haynes 188 type analysis and technical data",
        "url": "https://www.hightempmetals.com/techdata/hitempHaynes188data.php",
        "kind": "datasheet",
        "license": "Distributor technical data page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Ultimate tensile strength, bright annealed sheet at room temperature",
      "value": 946,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "bright annealed sheet, 0.029 to 0.050 in thick",
        "temperature": "RT (70 °F / 21 °C)",
        "unit_in_source": "137.2 ksi"
      },
      "method": "Average tensile value printed in a distributor technical data page",
      "status": "ground",
      "source": "hightempmetals-188",
      "where": "Average Tensile Data, Sheet table, row 70 °F (21 °C), ultimate column",
      "source_detail": {
        "title": "HAYNES 188 technical data, High Temp Metals",
        "id": "Haynes 188 type analysis and technical data",
        "url": "https://www.hightempmetals.com/techdata/hitempHaynes188data.php",
        "kind": "datasheet",
        "license": "Distributor technical data page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "elongation",
      "label": "Elongation in 2 in, bright annealed sheet at room temperature",
      "value": 53,
      "bound": "exact",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "form": "bright annealed sheet, 0.029 to 0.050 in thick",
        "temperature": "RT (70 °F / 21 °C)"
      },
      "method": "Average tensile value printed in a distributor technical data page",
      "status": "ground",
      "source": "hightempmetals-188",
      "where": "Average Tensile Data, Sheet table, row 70 °F (21 °C), elongation column",
      "source_detail": {
        "title": "HAYNES 188 technical data, High Temp Metals",
        "id": "Haynes 188 type analysis and technical data",
        "url": "https://www.hightempmetals.com/techdata/hitempHaynes188data.php",
        "kind": "datasheet",
        "license": "Distributor technical data page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "yield_strength",
      "label": "Yield strength 0.2 % offset, hot-rolled and solution-annealed plate at 538 °C",
      "value": 315,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "hot-rolled and solution-annealed plate",
        "temperature": "1000 °F (538 °C)",
        "unit_in_source": "45.7 ksi"
      },
      "method": "Elevated-temperature tensile value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Tensile Properties table, Hot-Rolled and Solution-annealed Plate, 1000 °F row",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Ultimate tensile strength, hot-rolled and solution-annealed plate at 538 °C",
      "value": 832,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "hot-rolled and solution-annealed plate",
        "temperature": "1000 °F (538 °C)",
        "unit_in_source": "120.6 ksi"
      },
      "method": "Elevated-temperature tensile value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Tensile Properties table, Hot-Rolled and Solution-annealed Plate, 1000 °F row",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "yield_strength",
      "label": "Yield strength 0.2 % offset, hot-rolled and solution-annealed plate at 982 °C",
      "value": 132,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "hot-rolled and solution-annealed plate",
        "temperature": "1800 °F (982 °C)",
        "unit_in_source": "19.2 ksi"
      },
      "method": "Elevated-temperature tensile value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Tensile Properties table, Hot-Rolled and Solution-annealed Plate, 1800 °F row",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Ultimate tensile strength, hot-rolled and solution-annealed plate at 982 °C",
      "value": 188,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "hot-rolled and solution-annealed plate",
        "temperature": "1800 °F (982 °C)",
        "unit_in_source": "27.2 ksi"
      },
      "method": "Elevated-temperature tensile value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Tensile Properties table, Hot-Rolled and Solution-annealed Plate, 1800 °F row",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Ultimate tensile strength, hot-rolled and solution-annealed plate at 1093 °C",
      "value": 96,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "hot-rolled and solution-annealed plate",
        "temperature": "2000 °F (1093 °C)",
        "unit_in_source": "13.9 ksi"
      },
      "method": "Elevated-temperature tensile value printed in a manufacturer product page",
      "status": "ground",
      "note": "The same table gives 188 MPa at 982 °C, so tensile strength falls by about half between 1800 °F and 2000 °F.",
      "source": "haynes-188-page",
      "where": "Tensile Properties table, Hot-Rolled and Solution-annealed Plate, 2000 °F row",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "max_service_temp",
      "label": "Long-term continuous exposure limit in air and combustion gases (oxidation)",
      "value": 1095,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "basis": "oxidation limit for long-term continuous exposure, not a mechanical limit",
        "unit_in_source": "2000 °F"
      },
      "method": "Value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Oxidation Resistance section, first paragraph",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "oxidation_metal_affected",
      "label": "Average metal affected (metal loss plus internal penetration), flowing air at 1150 °C for 1008 h",
      "value": 272,
      "bound": "exact",
      "unit": "µm",
      "scope": "material",
      "conditions": {
        "environment": "flowing air",
        "temperature": "2100 °F (1150 °C)",
        "time": "1008 h",
        "unit_in_source": "10.7 mils"
      },
      "method": "Comparative oxidation value printed in a manufacturer product page; the page footnote defines the figure as metal loss plus average internal penetration",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Comparative Oxidation Resistance in Flowing Air, 1008 Hours table, 188 row, 2100 °F column, average metal affected",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "oxidation_metal_loss",
      "label": "Metal loss, flowing air at 1150 °C for 1008 h",
      "value": 218,
      "bound": "exact",
      "unit": "µm",
      "scope": "material",
      "conditions": {
        "environment": "flowing air",
        "temperature": "2100 °F (1150 °C)",
        "time": "1008 h",
        "unit_in_source": "8.6 mils"
      },
      "method": "Comparative oxidation value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Comparative Oxidation Resistance in Flowing Air, 1008 Hours table, 188 row, 2100 °F column, metal loss",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "oxidation_metal_loss",
      "label": "Metal loss, flowing air at 1093 °C for 1008 h",
      "value": 13,
      "bound": "exact",
      "unit": "µm",
      "scope": "material",
      "conditions": {
        "environment": "flowing air",
        "temperature": "2000 °F (1093 °C)",
        "time": "1008 h",
        "unit_in_source": "0.5 mils"
      },
      "method": "Comparative oxidation value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Comparative Oxidation Resistance in Flowing Air, 1008 Hours table, 188 row, 2000 °F column, metal loss",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "creep_stress_1pct_1000h",
      "label": "Stress for 1 % creep in 1000 h at 982 °C, hot-rolled and solution-annealed plate",
      "value": 17,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "solution-annealed plate",
        "temperature": "1800 °F (982 °C)",
        "creep": "1 %",
        "time": "1000 h",
        "unit_in_source": "2.5 ksi"
      },
      "method": "Approximate creep stress printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Creep and Stress-Rupture table, 188 Plate, Solution-Annealed, 1800 °F row, 1 % creep, 1,000 h column",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "creep_stress_1pct_1000h",
      "label": "Stress for 1 % creep in 1000 h at 982 °C, solution-treated sheet",
      "value": 14,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "form": "solution-treated sheet",
        "temperature": "1800 °F (982 °C)",
        "creep": "1.0 %",
        "time": "1000 h",
        "unit_in_source": "2.1 ksi"
      },
      "method": "Average creep value printed in a distributor technical data page",
      "status": "ground",
      "source": "hightempmetals-188",
      "where": "Average Creep Data, Sheet table, 1800 (982) row, 1.0 % creep, 1000 hrs column",
      "source_detail": {
        "title": "HAYNES 188 technical data, High Temp Metals",
        "id": "Haynes 188 type analysis and technical data",
        "url": "https://www.hightempmetals.com/techdata/hitempHaynes188data.php",
        "kind": "datasheet",
        "license": "Distributor technical data page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Ultimate tensile strength at room temperature after 8000 h at 650 °C",
      "value": 1045,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "condition": "after 8000 h at 1200 °F (650 °C), then tested at room temperature",
        "unit_in_source": "151.6 ksi"
      },
      "method": "Value printed in a manufacturer product page, thermal stability table",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Impact and Thermal Stability section, Thermal Exposure table, room temperature row, UTS column",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "yield_strength",
      "label": "Yield strength 0.2 % offset at room temperature after 8000 h at 650 °C",
      "value": 550,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "condition": "after 8000 h at 1200 °F (650 °C), then tested at room temperature",
        "unit_in_source": "79.7 ksi"
      },
      "method": "Value printed in a manufacturer product page, thermal stability table",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Impact and Thermal Stability section, Thermal Exposure table, room temperature row, yield column",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "poissons_ratio",
      "label": "Poisson's ratio at room temperature, Haynes 188",
      "value": 0.3,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "temperature": "RT"
      },
      "method": "Value printed in a manufacturer product page",
      "status": "ground",
      "source": "haynes-188-page",
      "where": "Physical Properties table, Poisson's Ratio row, RT",
      "source_detail": {
        "title": "HAYNES 188 alloy, Haynes International product page",
        "id": "UNS R30188",
        "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
        "kind": "datasheet",
        "license": "Manufacturer product page (cited, not reproduced)"
      }
    },
    {
      "benchmark": "thermal_emittance",
      "label": "Thermal emittance of pristine surface, Haynes 188",
      "value": 0.11,
      "bound": "exact",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "surface": "pristine, as received",
        "note_on_range": "surface treatments raised emittance to between 0.28 and 0.86 in the same study"
      },
      "method": "Optical property value stated in a NASA technical memorandum",
      "status": "ground",
      "source": "nasa-tm-106549",
      "where": "Summary, first page, emittance of pristine Haynes 188",
      "source_detail": {
        "title": "Performance and Durability of High Emittance Heat Receiver Surfaces for Solar Dynamic Power Systems, NASA TM-106549",
        "id": "NASA TM-106549, NTRS 19940024331",
        "url": "https://ntrs.nasa.gov/api/citations/19940024331/downloads/19940024331.pdf",
        "year": 1994,
        "kind": "report",
        "license": "NASA public domain"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Air and combustion gases, 1095 to 1150 °C",
      "headline": "Haynes 188 shows very good oxidation resistance, rated for long-term continuous exposure up to 2000 °F (1095 °C).",
      "effect": "After 1008 h in flowing air at 2100 °F (1150 °C), the average metal affected is 10.7 mils (272 µm) and the metal loss is 8.6 mils (218 µm). At 2000 °F (1093 °C) the same test gives 3.7 mils (94 µm) affected and 0.5 mil (13 µm) metal loss, per Haynes International.",
      "rating": "moderate",
      "conditions": {
        "air_velocity": "flowing air",
        "cycling": "as printed in the table test method"
      },
      "source": "haynes-188-page",
      "where": "Oxidation Resistance section and Comparative Oxidation Resistance in Flowing Air, 1008 Hours table, 188 row"
    },
    {
      "environment": "Long-term thermal exposure at 650 °C, then room-temperature tensile test",
      "headline": "After 8000 h at 1200 °F (650 °C), room-temperature strength stays high and ductility is retained.",
      "effect": "Haynes International reports 550 MPa yield strength and 1045 MPa tensile strength after the 8000 h exposure, with 29.1 % elongation. A distributor page says the alloy keeps good ductility after 16,000 h at 1200, 1400 and 1600 °F (650, 760 and 870 °C).",
      "rating": "low",
      "conditions": {
        "time": "8000 h at 1200 °F (650 °C)"
      },
      "source": "haynes-188-page",
      "where": "Impact and Thermal Stability section, Thermal Exposure table; hightempmetals-188 Description"
    },
    {
      "environment": "Oxidising gas at high temperature above 1093 °C",
      "headline": "The loss rises sharply between 2000 °F and 2100 °F in the same flowing-air test.",
      "effect": "The metal loss increases from 0.5 mil (13 µm) at 2000 °F to 8.6 mils (218 µm) at 2100 °F after 1008 h, so the protection is not stable across that 100 °F step.",
      "rating": "moderate",
      "conditions": {
        "time": "1008 h"
      },
      "source": "haynes-188-page",
      "where": "Comparative Oxidation Resistance in Flowing Air, 1008 Hours table, 188 row, 2000 °F and 2100 °F columns"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "PubChem aggregated GHS for cobalt metal, from 2768 reports: H317 in more than 99.9 % of reports that give a code, H334 in more than 99.9 %, H341 in 65.8 %, H350 in 64.5 %, H360Fd in 61.6 %, H302 in 65.2 %, H330 in 23.4 %, H319 in 40.8 %, H413 in 54.9 %. Signal word Danger. These codes are for cobalt metal; the alloy is about 39 % cobalt, and nickel and chromium codes were not added.",
        "ghs": [
          "H317",
          "H334",
          "H341",
          "H350",
          "H360Fd",
          "H302",
          "H330",
          "H319",
          "H413"
        ],
        "source": "pubchem-cobalt",
        "where": "Safety and Hazards, GHS Classification, aggregated ECHA C&L notification block (2768 reports)"
      }
    ],
    "failure_risks": [
      {
        "mode": "Loss of strength at high temperature",
        "trigger": "Use under stress above about 1800 °F (982 °C)",
        "consequence": "Plate tensile strength falls from 991 MPa at room temperature to 188 MPa at 982 °C and 96 MPa at 1093 °C. One percent creep takes 17 MPa for 1000 h at 982 °C in plate.",
        "severity": "moderate",
        "source": "haynes-188-page",
        "where": "Tensile Properties table (plate rows RT, 1800 °F and 2000 °F) and Creep and Stress-Rupture table"
      },
      {
        "mode": "Oxidation metal loss above 2000 °F",
        "trigger": "Long exposure in flowing air at 2100 °F (1150 °C)",
        "consequence": "Metal loss reaches 8.6 mils (218 µm) after 1008 h, against 0.5 mil (13 µm) at 2000 °F, so wall thinning is far faster at 2100 °F.",
        "severity": "high",
        "source": "haynes-188-page",
        "where": "Comparative Oxidation Resistance in Flowing Air, 1008 Hours table, 188 row"
      },
      {
        "mode": "Low ductility near 760 °C",
        "trigger": "Service or cycling near 760 °C",
        "consequence": "NASA reports that Haynes 188 has a ductility minimum around 760 °C, and that low-cycle fatigue resistance follows ductility, so the cyclic strain capacity is also lowest near that temperature.",
        "severity": "moderate",
        "source": "nasa-n90-28642",
        "where": "Results discussion, paragraph on tensile ductility minimum around 760 °C"
      },
      {
        "mode": "Low-cycle fatigue in actively cooled panels",
        "trigger": "Panel walls up to 650 °C with high thermal gradients and high-pressure hydrogen, repeated runs",
        "consequence": "NASA Glenn states that actively cooled combustor walls of this alloy could challenge low-cycle fatigue durability in repeated runs. The presentation is the objective of the test program; no result is entered here.",
        "severity": "moderate",
        "source": "nasa-gabb-2011",
        "where": "Statement of Problem and Objective slides"
      }
    ],
    "side_effects": [],
    "handling": [
      {
        "text": "Solution heat treat at 2125 to 2175 °F (1163 to 1191 °C), then cool rapidly. Forging hold is 2150 °F (1175 °C).",
        "source": "haynes-188-page",
        "where": "Heat Treatment and Fabrication section"
      },
      {
        "text": "Solution treatment at 2150 °F ±25 °F (1177 °C ±14 °C) is the stated heat treatment; cold-worked parts are aged near 1000 °F (540 °C) for 4 to 16 hours.",
        "source": "hightempmetals-188",
        "where": "Heat-Treatment and Cold-Work and Aging section"
      }
    ],
    "mitigations": []
  },
  "uses": [
    {
      "application": "propulsion-and-tanks",
      "device": "Combustion cans in military and commercial gas turbine engines",
      "example": "Haynes International says the alloy is widely used in established military and commercial gas turbine engines for combustion cans, and in aerospace fabricated components. These are aircraft and land-based turbine uses.",
      "source": "haynes-188-page",
      "where": "Description and Principal Features text"
    },
    {
      "application": "propulsion-and-tanks",
      "device": "Liquid oxygen injection tubes (IDX posts) in the main combustion chamber of the Space Shuttle Main Engine",
      "example": "NASA lists the IDX posts as a space-related application of the alloy. This is a flown rocket-engine use described in a NASA technical memorandum.",
      "source": "nasa-n90-28642",
      "where": "Introduction, first page, space-related applications paragraph"
    },
    {
      "application": "thermal-control",
      "device": "Thermal energy storage containment canisters and working-fluid tubes in a solar dynamic receiver",
      "example": "NASA says Haynes 188 will be used for TES containment canisters in the 2 kW solar dynamic ground test demonstrator, and that the canisters need high emittance so they radiate heat away from hot spots. This is a planned ground-demonstrator design, not a flight record.",
      "source": "nasa-tm-106549",
      "where": "Summary and Introduction, paragraphs on TES containment canisters"
    },
    {
      "application": "propulsion-and-tanks",
      "device": "Actively cooled, hydrogen-cooled combustor wall panels in NASA's Durable Combustor Rig",
      "example": "NASA Glenn assessed low-cycle fatigue of Haynes 188 for actively cooled combustor walls at 25 and 650 °C in hydrogen and helium. This is a test-rig use, not a flight record.",
      "source": "nasa-gabb-2011",
      "where": "Statement of Problem and Objective slides"
    }
  ],
  "supply": [
    {
      "subject": "Cobalt (mine production, 2025)",
      "producers": [
        {
          "country": "Congo (Kinshasa)",
          "share_percent": 73,
          "year": 2025
        },
        {
          "country": "Indonesia",
          "share_percent": 14,
          "year": 2025
        }
      ],
      "critical_lists": [],
      "recycling": "USGS: cobalt content of purchased scrap was 25 % of estimated cobalt consumption in 2025.",
      "substitutes": [
        "USGS: depending on the application, substitution for cobalt could cause a loss in product performance or increased cost."
      ],
      "source": "usgs-mcs2026-cobalt",
      "where": "Events, Trends, and Issues (73 % and 14 % of world total); World Mine Production table, 2025 column (230,000 and 44,000 of 310,000 t, so the table gives about 74 % for Congo). Domestic Production and Use: 51 % of US cobalt consumed in superalloys, mainly aircraft gas turbine engines."
    },
    {
      "subject": "Nickel (mine production, 2025e)",
      "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
        }
      ],
      "critical_lists": [],
      "recycling": "USGS: nickel recovered from scrap accounted for approximately 60 % of 2025 apparent consumption.",
      "substitutes": [
        "USGS: titanium alloys can substitute for nickel or nickel-base alloys in corrosive environments."
      ],
      "source": "usgs-mcs2026-nickel",
      "where": "World Mine Production and Reserves table, 2025e column; shares calculated from the printed tonnages (Indonesia 2,600,000, Philippines 270,000 and Russia 200,000 of 3,900,000 t)"
    },
    {
      "subject": "Chromium (chromite ore mine production, 2025e)",
      "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
        }
      ],
      "critical_lists": [],
      "recycling": "USGS: recycled chromium in reported stainless-steel scrap receipts accounted for 21 % of 2025 apparent consumption.",
      "substitutes": [
        "USGS: chromium has no substitute in superalloys, the major strategic end use."
      ],
      "source": "usgs-mcs2026-chromium",
      "where": "World Mine Production and Reserves table, 2025e column; shares calculated from the printed tonnages (South Africa 23,000, Turkey 9,000 and Kazakhstan 7,000 of 51,000 t). Substitutes paragraph."
    },
    {
      "subject": "Tungsten (mine production, 2025)",
      "producers": [
        {
          "country": "China",
          "share_percent": 78.8,
          "year": 2025
        },
        {
          "country": "Vietnam",
          "share_percent": 3.5,
          "year": 2025
        },
        {
          "country": "Russia",
          "share_percent": 2.4,
          "year": 2025
        }
      ],
      "critical_lists": [],
      "recycling": "USGS: the quantity of secondary tungsten produced in 2025 was withheld to avoid disclosing proprietary data.",
      "substitutes": [
        "USGS: potential substitutes for cemented tungsten carbides include molybdenum, niobium and titanium carbides, ceramics, cermets and tool steels, which mostly reduce rather than replace tungsten use."
      ],
      "source": "usgs-mcs2026-tungsten",
      "where": "World Mine Production and Reserves table, 2025 column; shares calculated from the printed tonnages (China 67,000, Vietnam 3,000 and Russia 2,000 of 85,000 t); Events, Trends, and Issues on China's export controls"
    }
  ],
  "media": [],
  "documents": [
    {
      "title": "HAYNES 188 alloy product page, Haynes International (composition, physical, tensile, creep, oxidation and thermal stability tables)",
      "type": "datasheet",
      "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/"
    },
    {
      "title": "HAYNES 188 technical data, High Temp Metals (type analysis, physical properties, sheet tensile and creep tables)",
      "type": "datasheet",
      "url": "https://www.hightempmetals.com/techdata/hitempHaynes188data.php"
    },
    {
      "title": "PubChem: Cobalt (CID 104730), GHS classification (PUG View JSON)",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/104730/JSON?heading=GHS+Classification"
    },
    {
      "title": "Mineral Commodity Summaries 2026: Cobalt (USGS)",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-cobalt.pdf",
      "year": 2026
    },
    {
      "title": "Mineral Commodity Summaries 2026: Nickel (USGS)",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf",
      "year": 2026
    },
    {
      "title": "Mineral Commodity Summaries 2026: Chromium (USGS)",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf",
      "year": 2026
    },
    {
      "title": "Mineral Commodity Summaries 2026: Tungsten (USGS)",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-tungsten.pdf",
      "year": 2026
    },
    {
      "title": "High Temperature Fatigue Behavior of Haynes 188, NASA Lewis (Halford, Saltsman, Kalluri), NTRS N90-28642",
      "type": "report",
      "url": "https://ntrs.nasa.gov/api/citations/19900019326/downloads/19900019326.pdf",
      "year": 1990
    },
    {
      "title": "Fatigue Life of Haynes 188 Superalloy in Hydrogen, NASA Glenn (Gabb et al.), presented 2011",
      "type": "report",
      "url": "https://ntrs.nasa.gov/api/citations/20150010332/downloads/20150010332.pdf",
      "year": 2011
    },
    {
      "title": "Performance and Durability of High Emittance Heat Receiver Surfaces for Solar Dynamic Power Systems, NASA TM-106549 (de Groh)",
      "type": "report",
      "url": "https://ntrs.nasa.gov/api/citations/19940024331/downloads/19940024331.pdf",
      "year": 1994
    }
  ],
  "gaps": [
    "Specific heat: the manufacturer page prints 0.096 Btu/lb-°F at room temperature, but the metric value printed beside it is garbled, so only the customary value is entered.",
    "Melting range differs by source: the manufacturer gives 1315 to 1410 °C as the melting temperature, the distributor gives 1302 to 1330 °C as incipient fusion. Both are entered; no third source was found.",
    "AMS specification for HAYNES 188 itself: not found in any source we hold. The AMS numbers on the manufacturer page belong to filler products for other alloys.",
    "Product forms: sheet, plate and bar appear in the manufacturer's tables; wire is implied by the filler section only. A full list of forms and sizes: not found in any source we hold.",
    "Creep and rupture: one stress and time point per form is entered. The full creep and rupture tables, and the low-cycle fatigue curves (images with no extractable text), are not entered.",
    "Charpy V-notch impact from -300 °F to 1300 °F, and hardness values: printed on the manufacturer page, but no canonical property name exists for them, so they are not entered.",
    "Corrosion beyond air and combustion-gas oxidation: the manufacturer page has sulfidation, corrosion and water-vapour tables that were not extracted into this profile. Aqueous corrosion data: not found in any source we hold.",
    "Safety data sheet for solid HAYNES 188 stock: not found in any source we hold. Hazard codes come from the PubChem cobalt metal record only; nickel and chromium codes were not added.",
    "Critical-mineral list status: the USGS 2026 summaries read here print no critical-list status for cobalt, nickel, chromium or tungsten, so critical_lists is empty.",
    "Flight record: the Shuttle main engine use is a flown application. The solar-receiver canister and the Durable Combustor Rig panels are planned or test-rig uses, and the Orbital Maneuvering Engine combustion chamber is described only as a potential use. None is counted as a flight record here.",
    "Custom benchmark names: oxidation_metal_affected, oxidation_metal_loss, creep_stress_1pct_1000h and thermal_emittance are not in the canonical list. Each is used as printed in the source.",
    "Tungsten recycling: USGS withheld the 2025 secondary tungsten figure, so no recycling share is given."
  ],
  "story": {
    "why": "Haynes 188 is a cobalt-base superalloy used for gas-turbine combustion cans and hot parts that must resist oxidation. Haynes International gives its nominal composition as 39 % cobalt, 22 % nickel, 22 % chromium and 14 % tungsten. The USGS reports that an estimated 51 % of US cobalt consumption in 2025 went to superalloys, mainly for aircraft gas turbine engines.",
    "uses": [
      {
        "where": "Gas-turbine combustion cans",
        "line": "Haynes International says the alloy is widely used in military and commercial gas turbine engines for combustion cans."
      },
      {
        "where": "Space Shuttle Main Engine",
        "line": "NASA lists the liquid oxygen injection tubes (IDX posts) in the main combustion chamber of the Space Shuttle Main Engine as a space-related use."
      },
      {
        "where": "Solar dynamic thermal storage",
        "line": "NASA says the alloy will be used for thermal energy storage containment canisters in a 2 kW solar dynamic ground demonstrator. This is a planned design, not a flight record."
      },
      {
        "where": "Hydrogen-cooled combustor panels",
        "line": "NASA Glenn assessed low-cycle fatigue of the alloy for actively cooled combustor walls at 25 and 650 °C in hydrogen and helium, in the Durable Combustor Rig."
      }
    ],
    "can_do": [
      {
        "label": "Resist oxidation",
        "line": "Haynes International rates the alloy for long-term continuous exposure up to 2000 °F (1095 °C) in air and combustion gases.",
        "benchmark": "max_service_temp",
        "scope": "material",
        "value": "up to 2000 °F (1095 °C)"
      },
      {
        "label": "Carry heat",
        "line": "Thermal conductivity is 10.4 W/m-°C at room temperature and 27.6 W/m-°C at 1000 °C, per Haynes International.",
        "benchmark": "thermal_conductivity",
        "scope": "material",
        "value": "10.4 W/m-°C"
      },
      {
        "label": "Weight",
        "line": "Density is 8.98 g/cm3 at 22 °C (72 °F), per High Temp Metals.",
        "benchmark": "density",
        "scope": "material",
        "value": "8.98 g/cm3"
      },
      {
        "label": "Melting",
        "line": "The manufacturer gives a melting temperature range of 1315 to 1410 °C (2400 to 2570 °F).",
        "benchmark": "melting_point",
        "scope": "material",
        "value": "1315 to 1410 °C"
      },
      {
        "label": "Strength at room temperature",
        "line": "Hot-rolled and solution-annealed plate has a room-temperature 0.2 % yield strength of 483 MPa and a tensile strength of 991 MPa.",
        "benchmark": "yield_strength",
        "scope": "material",
        "value": "483 MPa yield"
      }
    ],
    "compare": "Within the manufacturer's flowing-air test, Haynes 188 loses 0.5 mil (13 µm) at 2000 °F and 8.6 mils (218 µm) at 2100 °F after 1008 h, so its oxide protection drops sharply across that 100 °F step. Its plate tensile strength halves from 991 MPa at room temperature to 188 MPa at 982 °C, and 96 MPa at 1093 °C. This profile gives no numbers for other alloys, because none were read in the sources held for this run.",
    "compare_rows": [
      {
        "label": "Density",
        "benchmark": "density",
        "scope": "material"
      },
      {
        "label": "Thermal conductivity",
        "benchmark": "thermal_conductivity",
        "scope": "material"
      },
      {
        "label": "Yield strength",
        "benchmark": "yield_strength",
        "scope": "material"
      }
    ],
    "handling": [
      "Specify the temper and form, because the tensile values differ between plate and sheet.",
      "Keep restrained welds and hot-worked parts within the solution heat treatment range, then cool rapidly.",
      "Do not hold the alloy under high stress above about 1800 °F (982 °C), where its strength is low."
    ],
    "good_for": [
      "Oxidation resistance up to 2000 °F (1095 °C) for long-term continuous exposure, per Haynes International.",
      "Hot combustor parts and actively cooled hot-structure panels, per Haynes International and NASA.",
      "Thermal storage canisters that need a high-emittance surface, where a surface treatment can raise emittance from 0.11 to between 0.28 and 0.86, per NASA."
    ],
    "watch_out": [
      "Strength falls sharply above about 1800 °F (982 °C): plate tensile strength is 188 MPa at 982 °C and 96 MPa at 1093 °C.",
      "Oxidation loss rises from 0.5 mil (13 µm) at 2000 °F to 8.6 mils (218 µm) at 2100 °F after 1008 h.",
      "NASA reports a ductility minimum around 760 °C, where cyclic strain capacity is lowest.",
      "The cobalt content carries the PubChem hazard codes, including skin and respiratory sensitisation."
    ],
    "verdict": "Haynes 188 is a cobalt-base superalloy for hot oxidising gas up to 2000 °F (1095 °C) in combustion parts and hot structure. It keeps useful tensile strength to about 1800 °F (982 °C) and loses oxide protection quickly at 2100 °F. Its spaceflight record is limited to a Shuttle engine use, and its solar and combustor uses are planned or tested.",
    "recipe": {
      "line": "Haynes 188 is a wrought cobalt-base superalloy with a nominal composition of 39 % cobalt (balance), 22 % nickel, 22 % chromium and 14 % tungsten, with small manganese, silicon, carbon, lanthanum and boron additions (Haynes International). It is supplied hot-rolled and solution-annealed, with a solution heat treatment at 2125 to 2175 °F (1163 to 1191 °C) (Haynes International).",
      "parts": [
        {
          "name": "Cobalt",
          "symbol": "Co",
          "role": "Matrix of the alloy",
          "share_percent": 39,
          "share_note": "nominal, balance (Haynes International)"
        },
        {
          "name": "Nickel",
          "symbol": "Ni",
          "role": "Austenitic matrix element",
          "share_percent": 22,
          "share_note": "nominal (Haynes International)"
        },
        {
          "name": "Chromium",
          "symbol": "Cr",
          "role": "Oxide-scale former for oxidation resistance",
          "share_percent": 22,
          "share_note": "nominal (Haynes International)"
        },
        {
          "name": "Tungsten",
          "symbol": "W",
          "role": "Solid-solution strengthener",
          "share_percent": 14,
          "share_note": "nominal (Haynes International)"
        },
        {
          "name": "Iron",
          "symbol": "Fe",
          "role": "Impurity-level element",
          "share_percent": 3,
          "share_note": "maximum (Haynes International)"
        },
        {
          "name": "Manganese",
          "symbol": "Mn",
          "role": "Deoxidiser and minor element",
          "share_percent": 1.25,
          "share_note": "maximum (Haynes International)"
        },
        {
          "name": "Silicon",
          "symbol": "Si",
          "role": "Minor element",
          "share_percent": 0.35,
          "share_note": "nominal (Haynes International)"
        },
        {
          "name": "Carbon",
          "symbol": "C",
          "role": "Carbide former",
          "share_percent": 0.1,
          "share_note": "nominal (Haynes International)"
        },
        {
          "name": "Lanthanum",
          "symbol": "La",
          "role": "Trace element that improves oxide-scale adhesion",
          "share_percent": 0.03,
          "share_note": "nominal (Haynes International)"
        },
        {
          "name": "Boron",
          "symbol": "B",
          "role": "Trace element",
          "share_percent": 0.015,
          "share_note": "maximum (Haynes International)"
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "The alloy is a solid metal. Its cobalt content carries the hazard codes in the PubChem cobalt metal record.",
        "points": [
          {
            "label": "Solid alloy",
            "line": "The PubChem aggregated cobalt record lists skin sensitisation (H317 in more than 99.9 % of reports that give a code), respiratory sensitisation (H334 in more than 99.9 %), suspected genetic defects (H341 in 65.8 %), may cause cancer (H350 in 64.5 %) and may damage fertility (H360Fd in 61.6 %). Signal word Danger."
          },
          {
            "label": "Fume and dust",
            "line": "The sources read give no safety data for welding fume or grinding dust from this alloy. Treat them as cobalt fume until a safety data sheet is found."
          }
        ],
        "level": 1,
        "verdict": "Cobalt codes apply"
      },
      {
        "title": "If it fails",
        "lead": "These failure routes come from the manufacturer's test data and NASA test notes.",
        "points": [
          {
            "label": "Strength at high temperature",
            "line": "Plate tensile strength falls from 991 MPa at room temperature to 188 MPa at 982 °C and 96 MPa at 1093 °C."
          },
          {
            "label": "Oxidation at 2100 °F",
            "line": "Metal loss is 8.6 mils (218 µm) after 1008 h at 2100 °F, against 0.5 mil (13 µm) at 2000 °F."
          },
          {
            "label": "Ductility near 760 °C",
            "line": "NASA reports a ductility minimum around 760 °C, where the cyclic strain capacity is also lowest."
          }
        ]
      },
      {
        "title": "Handling and storage",
        "points": [
          {
            "label": "Heat treatment",
            "line": "Solution heat treat at 2125 to 2175 °F (1163 to 1191 °C), then cool rapidly. Cold-worked parts are aged near 1000 °F (540 °C) for 4 to 16 hours."
          }
        ]
      }
    ]
  },
  "updated": "2026-11-01",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 31,
    "unreachable": 0,
    "caveats": 6,
    "note": "Values were read by an AI assistant on 2026-11-01 from the Haynes International HAYNES 188 product page, the High Temp Metals Haynes 188 data page, NASA NTRS papers N90-28642 and TM-106549, the 2011 NASA Glenn Gabb presentation, the PubChem cobalt GHS record and the USGS MCS 2026 cobalt, nickel, chromium and tungsten summaries. The oxidation and tensile values were read twice in this run. Caveats: the manufacturer and distributor pages are summarised text, the sheet and plate tensile data are different product forms, the melting ranges differ between sources, the hazard codes are for cobalt metal, and the NASA uses are older or planned."
  },
  "sources": {
    "haynes-188-page": {
      "title": "HAYNES 188 alloy, Haynes International product page",
      "id": "UNS R30188",
      "url": "https://haynesintl.com/en/alloys/alloy-portfolio/high-temperature-alloys/haynes-188/",
      "kind": "datasheet",
      "license": "Manufacturer product page (cited, not reproduced)"
    },
    "hightempmetals-188": {
      "title": "HAYNES 188 technical data, High Temp Metals",
      "id": "Haynes 188 type analysis and technical data",
      "url": "https://www.hightempmetals.com/techdata/hitempHaynes188data.php",
      "kind": "datasheet",
      "license": "Distributor technical data page (cited, not reproduced)"
    },
    "pubchem-cobalt": {
      "title": "PubChem: Cobalt (CID 104730), GHS classification",
      "id": "PubChem CID 104730, aggregated ECHA C&L notifications",
      "url": "https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/104730/JSON?heading=GHS+Classification",
      "kind": "database",
      "license": "PubChem (NIH), public domain"
    },
    "usgs-mcs2026-cobalt": {
      "title": "Mineral Commodity Summaries 2026: Cobalt",
      "id": "USGS MCS 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-cobalt.pdf",
      "year": 2026,
      "kind": "report",
      "license": "Public domain (USGS)"
    },
    "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)"
    },
    "usgs-mcs2026-tungsten": {
      "title": "Mineral Commodity Summaries 2026: Tungsten",
      "id": "USGS MCS 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-tungsten.pdf",
      "year": 2026,
      "kind": "report",
      "license": "Public domain (USGS)"
    },
    "nasa-n90-28642": {
      "title": "High Temperature Fatigue Behavior of Haynes 188, NASA Technical Memorandum (Halford, Saltsman, Kalluri)",
      "id": "NTRS N90-28642",
      "url": "https://ntrs.nasa.gov/api/citations/19900019326/downloads/19900019326.pdf",
      "year": 1990,
      "kind": "report",
      "license": "NASA public domain"
    },
    "nasa-gabb-2011": {
      "title": "Fatigue Life of Haynes 188 Superalloy in Hydrogen, NASA Glenn (Gabb et al.)",
      "id": "NTRS 20150010332",
      "url": "https://ntrs.nasa.gov/api/citations/20150010332/downloads/20150010332.pdf",
      "year": 2011,
      "kind": "report",
      "license": "NASA public domain"
    },
    "nasa-tm-106549": {
      "title": "Performance and Durability of High Emittance Heat Receiver Surfaces for Solar Dynamic Power Systems, NASA TM-106549",
      "id": "NASA TM-106549, NTRS 19940024331",
      "url": "https://ntrs.nasa.gov/api/citations/19940024331/downloads/19940024331.pdf",
      "year": 1994,
      "kind": "report",
      "license": "NASA public domain"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/haynes-188/"
}