{
  "spore": "profile",
  "id": "tool-steel-d2",
  "spore_version": "0.2",
  "family": "tool-steels",
  "name": "AISI D2 cold-work tool steel (EN 1.2379, X153CrMoV12)",
  "abbreviation": "D2 (UNS T30402, EN 1.2379)",
  "role": "cold-work tool steel",
  "category": "metals",
  "type": "steels-and-stainless",
  "summary": "AISI D2 (EN 1.2379, X153CrMoV12, JIS SKD 11) is a high-carbon, about 12 percent chromium cold-work tool steel. Hard carbides give it very good abrasive wear resistance, and it is used for blanking, forming and cutting tools. Its hardness and toughness depend entirely on heat treatment, and it is not a stainless steel.",
  "best_for": "Blanking, punching, forming and cutting tools that need high wear resistance more than toughness",
  "weakest_at": "Toughness and corrosion: rather limited cracking resistance (Uddeholm), and corrosion resistance below that of stainless steel (Wikipedia)",
  "identity": {
    "formula": "Fe balance; 1.40 to 1.60 C, 0.10 to 0.60 Si, 0.10 to 0.60 Mn, 11.00 to 13.00 Cr, 0.70 to 1.20 Mo, 0.50 to 1.10 V, 0.00 to 0.03 P, 0.00 to 0.03 S (wt%, composition ranges from the Steel Service Krefeld SDS, section 3); typical analysis 1.55 C, 0.3 Si, 0.4 Mn, 11.3 Cr, 0.8 Mo, 0.8 V (wt%, Uddeholm)",
    "designations": [
      {
        "system": "AISI",
        "code": "D2"
      },
      {
        "system": "Name",
        "code": "D2"
      },
      {
        "system": "EN",
        "code": "1.2379"
      },
      {
        "system": "EN name",
        "code": "X153CrMoV12"
      },
      {
        "system": "UNS",
        "code": "T30402"
      },
      {
        "system": "JIS",
        "code": "SKD 11"
      },
      {
        "system": "Name",
        "code": "Cr12MoV"
      },
      {
        "system": "Name",
        "code": "Cr12Mo1V1"
      },
      {
        "system": "Name",
        "code": "THYRODUR 2379"
      }
    ],
    "source": "uddeholm-sverker21",
    "where": "Page 3, General: typical analysis and standard specification AISI D2, W.-Nr. 1.2379; composition ranges from SDS section 3; designations from the Dörrenberg datasheet (Code X153CrMoV12), the Total Materia cross-reference table (UNS, DIN, JIS, GB and trade names, some marked implicit there) and the SDS title"
  },
  "tags": {
    "environments": [],
    "stresses": [],
    "applications": [
      "mechanisms"
    ]
  },
  "properties": [
    {
      "benchmark": "density",
      "label": "Density at 20 C",
      "value": 7700,
      "bound": "exact",
      "unit": "kg/m3",
      "scope": "material",
      "conditions": {
        "heat_treatment": "hardened and tempered to 62 HRC (the sheet's state for physical data)",
        "temperature": "20 C (68 F)"
      },
      "method": "Physical data table as printed (7 700 kg/m3, 20 C column)",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Physical data table, Density row, 20 C column",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "density",
      "label": "Density at 400 C",
      "value": 7600,
      "bound": "exact",
      "unit": "kg/m3",
      "scope": "material",
      "conditions": {
        "heat_treatment": "hardened and tempered to 62 HRC (the sheet's state for physical data)",
        "temperature": "400 C (750 F)"
      },
      "method": "Physical data table as printed (7 600 kg/m3, 400 C column)",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Physical data table, Density row, 400 C column",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Modulus of elasticity at 20 C",
      "value": 210000,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "heat_treatment": "hardened and tempered to 62 HRC (the sheet's state for physical data)",
        "temperature": "20 C (68 F)"
      },
      "method": "Physical data table as printed (210 000 MPa, 20 C column); 30 450 ksi alongside",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Physical data table, Modulus of elasticity row, MPa, 20 C column",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Modulus of elasticity at 400 C",
      "value": 180000,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "heat_treatment": "hardened and tempered to 62 HRC (the sheet's state for physical data)",
        "temperature": "400 C (750 F)"
      },
      "method": "Physical data table as printed (180 000 MPa, 400 C column)",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Physical data table, Modulus of elasticity row, MPa, 400 C column",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "specific_heat",
      "label": "Specific heat at 20 C",
      "value": 460,
      "bound": "exact",
      "unit": "J/kg °C",
      "scope": "material",
      "conditions": {
        "heat_treatment": "hardened and tempered to 62 HRC (the sheet's state for physical data)",
        "temperature": "20 C (68 F)"
      },
      "method": "Physical data table as printed (460 J/kg °C; 0.110 Btu/lb F alongside); the other two columns are not given",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Physical data table, Specific heat row, 20 C column",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "cte",
      "label": "Thermal expansion, 20 to 200 C, after low-temperature tempering",
      "value": 12.3,
      "bound": "exact",
      "unit": "ppm/K",
      "scope": "material",
      "conditions": {
        "heat_treatment": "hardened and tempered to 62 HRC, low-temperature tempering (the temperature is not defined in the sheet)",
        "temperature": "20 to 200 C (68 to 390 F)",
        "unit_in_source": "10-6 per degC, printed as 12.3 x 10-6"
      },
      "method": "Physical data table, 'at low temperature tempering' row, per degC from 20 C, 200 C column; the printed number is the same as ppm/K",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Physical data table, coefficient of thermal expansion, low-temperature tempering, 200 C column",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "cte",
      "label": "Thermal expansion, 20 to 200 C, after high-temperature tempering",
      "value": 11.2,
      "bound": "exact",
      "unit": "ppm/K",
      "scope": "material",
      "conditions": {
        "heat_treatment": "hardened and tempered to 62 HRC, high-temperature tempering (the temperature is not defined in the sheet)",
        "temperature": "20 to 200 C (68 to 390 F)",
        "unit_in_source": "10-6 per degC, printed as 11.2 x 10-6"
      },
      "method": "Physical data table, 'at high temperature tempering' row, per degC from 20 C, 200 C column; the printed number is the same as ppm/K",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Physical data table, coefficient of thermal expansion, high-temperature tempering, 200 C column",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "cte",
      "label": "Thermal expansion, 20 to 400 C, after high-temperature tempering",
      "value": 12,
      "bound": "exact",
      "unit": "ppm/K",
      "scope": "material",
      "conditions": {
        "heat_treatment": "hardened and tempered to 62 HRC, high-temperature tempering (the temperature is not defined in the sheet)",
        "temperature": "20 to 400 C (68 to 750 F)",
        "unit_in_source": "10-6 per degC, printed as 12 x 10-6"
      },
      "method": "Physical data table, 'at high temperature tempering' row, per degC from 20 C, 400 C column; the printed number is the same as ppm/K",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Physical data table, coefficient of thermal expansion, high-temperature tempering, 400 C column",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity at 20 C",
      "value": 20,
      "bound": "exact",
      "unit": "W/mK",
      "scope": "material",
      "conditions": {
        "heat_treatment": "hardened and tempered to 62 HRC (the sheet's state for physical data)",
        "temperature": "20 C (68 F)"
      },
      "method": "Physical data table, Thermal conductivity W/m °C row, 20 C column, printed as 20,0 with a decimal comma; 139 Btu in/ft2 h F alongside",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Physical data table, Thermal conductivity row, 20 C column",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity at 200 C",
      "value": 21,
      "bound": "exact",
      "unit": "W/mK",
      "scope": "material",
      "conditions": {
        "heat_treatment": "hardened and tempered to 62 HRC (the sheet's state for physical data)",
        "temperature": "200 C (390 F)"
      },
      "method": "Physical data table, Thermal conductivity W/m °C row, 200 C column, printed as 21,0 with a decimal comma",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Physical data table, Thermal conductivity row, 200 C column",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity at 400 C",
      "value": 23,
      "bound": "exact",
      "unit": "W/mK",
      "scope": "material",
      "conditions": {
        "heat_treatment": "hardened and tempered to 62 HRC (the sheet's state for physical data)",
        "temperature": "400 C (750 F)"
      },
      "method": "Physical data table, Thermal conductivity W/m °C row, 400 C column, printed as 23,0 with a decimal comma",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Physical data table, Thermal conductivity row, 400 C column",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "compressive_yield_strength",
      "label": "Compressive yield strength (Rc0.2) at 62 HRC",
      "value": 2200,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "heat_treatment": "hardness 62 HRC (the table does not state the tempering temperature)",
        "basis": "figures are approximate, as the sheet prints them"
      },
      "method": "Compressive strength table, Compressive yield strength Rc0,2 MPa column, 62 HRC row, printed as 2200 MPa (319 ksi)",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Compressive strength table, 62 HRC row",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "compressive_yield_strength",
      "label": "Compressive yield strength (Rc0.2) at 50 HRC",
      "value": 1650,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "heat_treatment": "hardness 50 HRC (the table does not state the tempering temperature)",
        "basis": "figures are approximate, as the sheet prints them"
      },
      "method": "Compressive strength table, Compressive yield strength Rc0,2 MPa column, 50 HRC row, printed as 1650 MPa (239 ksi)",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Compressive strength table, 50 HRC row",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_rockwell_c",
      "label": "Hardness before tempering after hardening at 990 C",
      "value": 63,
      "bound": "exact",
      "unit": "HRC",
      "scope": "material",
      "conditions": {
        "heat_treatment": "austenitized at 990 C for 60 min soaking time, hardness before tempering",
        "note": "quench medium not stated for this row"
      },
      "method": "Hardening table, Hardness before tempering column, printed as approx. 63 HRC",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 4, Hardening table, 990 C (1815 F) row",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_rockwell_c",
      "label": "Hardness before tempering after hardening at 1010 C",
      "value": 64,
      "bound": "exact",
      "unit": "HRC",
      "scope": "material",
      "conditions": {
        "heat_treatment": "austenitized at 1010 C for 45 min soaking time, hardness before tempering",
        "note": "quench medium not stated for this row"
      },
      "method": "Hardening table, Hardness before tempering column, printed as approx. 64 HRC",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 4, Hardening table, 1010 C (1850 F) row",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_rockwell_c",
      "label": "Hardness before tempering after hardening at 1030 C",
      "value": 65,
      "bound": "exact",
      "unit": "HRC",
      "scope": "material",
      "conditions": {
        "heat_treatment": "austenitized at 1030 C for 30 min soaking time, hardness before tempering",
        "note": "quench medium not stated for this row"
      },
      "method": "Hardening table, Hardness before tempering column, printed as approx. 65 HRC",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 4, Hardening table, 1030 C (1885 F) row",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_rockwell_c",
      "label": "Hardness before tempering after hardening at 1080 C",
      "value": 64,
      "bound": "exact",
      "unit": "HRC",
      "scope": "material",
      "conditions": {
        "heat_treatment": "austenitized at 1080 C for 30 min soaking time, hardness before tempering",
        "note": "quench medium not stated for this row"
      },
      "method": "Hardening table, Hardness before tempering column, printed as approx. 64 HRC",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 4, Hardening table, 1080 C (1975 F) row",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_brinell",
      "label": "Hardness, soft-annealed delivery condition",
      "value": 210,
      "bound": "exact",
      "unit": "HB",
      "scope": "material",
      "conditions": {
        "heat_treatment": "soft annealed: 850 C, furnace cooled at 10 C per hour to 650 C, then air cooled",
        "basis": "delivery condition, approximate as printed"
      },
      "method": "Typical analysis table, Delivery condition row, printed as soft annealed to approx. 210 HB",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Typical analysis table, Delivery condition row; annealing cycle on page 4, Soft annealing",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "surface_hardness_hv",
      "label": "Surface hardness after nitriding at 525 C",
      "value": 1250,
      "bound": "exact",
      "unit": "HV1",
      "scope": "material",
      "conditions": {
        "heat_treatment": "nitrided at 525 C (time not stated for this value)",
        "basis": "figures refer to hardened and tempered material, as printed"
      },
      "method": "Nitriding paragraph, printed as approx. 1250 HV1",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 5, Nitriding and nitrocarburizing, 525 C sentence",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "surface_hardness_hv",
      "label": "Surface hardness after nitrocarburizing at 570 C",
      "value": 950,
      "bound": "exact",
      "unit": "HV1",
      "scope": "material",
      "conditions": {
        "heat_treatment": "nitrocarburized at 570 C for 2 h",
        "basis": "figures refer to hardened and tempered material, as printed"
      },
      "method": "Nitriding paragraph, printed as approx. 950 HV1",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 5, Nitriding and nitrocarburizing, 570 C sentence",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "case_depth",
      "label": "Nitrided case depth at 525 C for 30 h",
      "value": 0.3,
      "bound": "exact",
      "unit": "mm",
      "scope": "material",
      "conditions": {
        "heat_treatment": "nitrided at 525 C for 30 h",
        "basis": "case depth table, approximate as printed"
      },
      "method": "Nitriding table, 525 C, 30 h row, printed as 0.30 mm (0.012 in)",
      "status": "ground",
      "source": "uddeholm-sverker21",
      "where": "Page 5, Nitriding table, 525 C, 30 h row",
      "source_detail": {
        "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
        "id": "Edition 13, 04.2019",
        "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
        "year": 2019,
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_brinell",
      "label": "Maximum hardness, soft-annealed delivery condition",
      "value": 255,
      "bound": "upper",
      "unit": "HB",
      "scope": "material",
      "conditions": {
        "heat_treatment": "soft annealed at 820 to 850 C, furnace cooled",
        "basis": "delivery condition, maximum as printed"
      },
      "method": "Condition of delivery and Soft annealing rows, printed as max. 255 HB",
      "status": "ground",
      "source": "doerrenberg-1-2379",
      "where": "Heat treatment table, Soft annealing row, and Condition of delivery (Dörrenberg datasheet)",
      "source_detail": {
        "title": "Dörrenberg Edelstahl: 1.2379 X153CrMoV12 datasheet (English, similar to AISI D2)",
        "id": "Material No. 1.2379, code X153CrMoV12",
        "url": "https://doerrenberg.de/fileadmin/special_steel/files/pdf_en_products_neues_Design/1.2379_en.pdf",
        "kind": "datasheet",
        "license": "supplier datasheet, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_rockwell_c",
      "label": "Hardness after tempering at 100 C",
      "value": 63,
      "bound": "exact",
      "unit": "HRC",
      "scope": "material",
      "conditions": {
        "heat_treatment": "tempered at 100 C; tempering time and hardening temperature not stated in the table",
        "basis": "curve from the thesis's reference 6, as printed"
      },
      "method": "Table 2.3, D2 hardness in HRC against tempering temperature, value as printed",
      "status": "ground",
      "source": "thesis-d2-tempering",
      "where": "Section 2.1.4.3, Table 2.3, column T 100 C",
      "source_detail": {
        "title": "Določanje popustnih karakteristik orodnega jekla D2 (Determining the tempering characteristics of D2 tool steel), bachelor's thesis, Faculty of Mechanical Engineering, University of Ljubljana (in Slovenian)",
        "id": "Jakob Jakše, May 2024",
        "url": "https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=186121&dn=",
        "year": 2024,
        "kind": "report",
        "license": "university repository copy, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_rockwell_c",
      "label": "Hardness after tempering at 200 C",
      "value": 61,
      "bound": "exact",
      "unit": "HRC",
      "scope": "material",
      "conditions": {
        "heat_treatment": "tempered at 200 C; tempering time and hardening temperature not stated in the table",
        "basis": "curve from the thesis's reference 6, as printed"
      },
      "method": "Table 2.3, D2 hardness in HRC against tempering temperature, value as printed",
      "status": "ground",
      "source": "thesis-d2-tempering",
      "where": "Section 2.1.4.3, Table 2.3, column T 200 C",
      "source_detail": {
        "title": "Določanje popustnih karakteristik orodnega jekla D2 (Determining the tempering characteristics of D2 tool steel), bachelor's thesis, Faculty of Mechanical Engineering, University of Ljubljana (in Slovenian)",
        "id": "Jakob Jakše, May 2024",
        "url": "https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=186121&dn=",
        "year": 2024,
        "kind": "report",
        "license": "university repository copy, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_rockwell_c",
      "label": "Hardness after tempering at 300 C",
      "value": 58,
      "bound": "exact",
      "unit": "HRC",
      "scope": "material",
      "conditions": {
        "heat_treatment": "tempered at 300 C; tempering time and hardening temperature not stated in the table",
        "basis": "curve from the thesis's reference 6, as printed"
      },
      "method": "Table 2.3, D2 hardness in HRC against tempering temperature, value as printed",
      "status": "ground",
      "source": "thesis-d2-tempering",
      "where": "Section 2.1.4.3, Table 2.3, column T 300 C",
      "source_detail": {
        "title": "Določanje popustnih karakteristik orodnega jekla D2 (Determining the tempering characteristics of D2 tool steel), bachelor's thesis, Faculty of Mechanical Engineering, University of Ljubljana (in Slovenian)",
        "id": "Jakob Jakše, May 2024",
        "url": "https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=186121&dn=",
        "year": 2024,
        "kind": "report",
        "license": "university repository copy, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_rockwell_c",
      "label": "Hardness after tempering at 400 C",
      "value": 58,
      "bound": "exact",
      "unit": "HRC",
      "scope": "material",
      "conditions": {
        "heat_treatment": "tempered at 400 C; tempering time and hardening temperature not stated in the table",
        "basis": "curve from the thesis's reference 6, as printed"
      },
      "method": "Table 2.3, D2 hardness in HRC against tempering temperature, value as printed",
      "status": "ground",
      "source": "thesis-d2-tempering",
      "where": "Section 2.1.4.3, Table 2.3, column T 400 C",
      "source_detail": {
        "title": "Določanje popustnih karakteristik orodnega jekla D2 (Determining the tempering characteristics of D2 tool steel), bachelor's thesis, Faculty of Mechanical Engineering, University of Ljubljana (in Slovenian)",
        "id": "Jakob Jakše, May 2024",
        "url": "https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=186121&dn=",
        "year": 2024,
        "kind": "report",
        "license": "university repository copy, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_rockwell_c",
      "label": "Hardness after tempering at 500 C",
      "value": 59,
      "bound": "exact",
      "unit": "HRC",
      "scope": "material",
      "conditions": {
        "heat_treatment": "tempered at 500 C; tempering time and hardening temperature not stated in the table",
        "basis": "curve from the thesis's reference 6, as printed"
      },
      "method": "Table 2.3, D2 hardness in HRC against tempering temperature, value as printed",
      "status": "ground",
      "source": "thesis-d2-tempering",
      "where": "Section 2.1.4.3, Table 2.3, column T 500 C",
      "source_detail": {
        "title": "Določanje popustnih karakteristik orodnega jekla D2 (Determining the tempering characteristics of D2 tool steel), bachelor's thesis, Faculty of Mechanical Engineering, University of Ljubljana (in Slovenian)",
        "id": "Jakob Jakše, May 2024",
        "url": "https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=186121&dn=",
        "year": 2024,
        "kind": "report",
        "license": "university repository copy, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_rockwell_c",
      "label": "Hardness after tempering at 550 C",
      "value": 56,
      "bound": "exact",
      "unit": "HRC",
      "scope": "material",
      "conditions": {
        "heat_treatment": "tempered at 550 C; tempering time and hardening temperature not stated in the table",
        "basis": "curve from the thesis's reference 6, as printed"
      },
      "method": "Table 2.3, D2 hardness in HRC against tempering temperature, value as printed",
      "status": "ground",
      "source": "thesis-d2-tempering",
      "where": "Section 2.1.4.3, Table 2.3, column T 550 C",
      "source_detail": {
        "title": "Določanje popustnih karakteristik orodnega jekla D2 (Determining the tempering characteristics of D2 tool steel), bachelor's thesis, Faculty of Mechanical Engineering, University of Ljubljana (in Slovenian)",
        "id": "Jakob Jakše, May 2024",
        "url": "https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=186121&dn=",
        "year": 2024,
        "kind": "report",
        "license": "university repository copy, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_rockwell_c",
      "label": "Hardness after tempering at 600 C",
      "value": 51,
      "bound": "exact",
      "unit": "HRC",
      "scope": "material",
      "conditions": {
        "heat_treatment": "tempered at 600 C; tempering time and hardening temperature not stated in the table",
        "basis": "curve from the thesis's reference 6, as printed"
      },
      "method": "Table 2.3, D2 hardness in HRC against tempering temperature, value as printed",
      "status": "ground",
      "source": "thesis-d2-tempering",
      "where": "Section 2.1.4.3, Table 2.3, column T 600 C",
      "source_detail": {
        "title": "Določanje popustnih karakteristik orodnega jekla D2 (Determining the tempering characteristics of D2 tool steel), bachelor's thesis, Faculty of Mechanical Engineering, University of Ljubljana (in Slovenian)",
        "id": "Jakob Jakše, May 2024",
        "url": "https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=186121&dn=",
        "year": 2024,
        "kind": "report",
        "license": "university repository copy, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_rockwell_c",
      "label": "Hardness after tempering at 700 C",
      "value": 35,
      "bound": "exact",
      "unit": "HRC",
      "scope": "material",
      "conditions": {
        "heat_treatment": "tempered at 700 C; tempering time and hardening temperature not stated in the table",
        "basis": "curve from the thesis's reference 6, as printed"
      },
      "method": "Table 2.3, D2 hardness in HRC against tempering temperature, value as printed",
      "status": "ground",
      "source": "thesis-d2-tempering",
      "where": "Section 2.1.4.3, Table 2.3, column T 700 C",
      "source_detail": {
        "title": "Določanje popustnih karakteristik orodnega jekla D2 (Determining the tempering characteristics of D2 tool steel), bachelor's thesis, Faculty of Mechanical Engineering, University of Ljubljana (in Slovenian)",
        "id": "Jakob Jakše, May 2024",
        "url": "https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=186121&dn=",
        "year": 2024,
        "kind": "report",
        "license": "university repository copy, cited not reproduced"
      }
    },
    {
      "benchmark": "hardness_rockwell_c",
      "label": "Hardness after hardening, approximate range",
      "value": 62,
      "value_high": 64,
      "bound": "range",
      "unit": "HRC",
      "scope": "material",
      "conditions": {
        "heat_treatment": "as hardened from 1000 to 1040 C per the text; quench medium not specified in that sentence",
        "basis": "approximate, as printed in the text that cites reference 6"
      },
      "method": "Text of section 2.1.4.3, printed as approximately between 62 and 64 HRC after hardening",
      "status": "ground",
      "source": "thesis-d2-tempering",
      "where": "Section 2.1.4.3, text before Table 2.3",
      "source_detail": {
        "title": "Določanje popustnih karakteristik orodnega jekla D2 (Determining the tempering characteristics of D2 tool steel), bachelor's thesis, Faculty of Mechanical Engineering, University of Ljubljana (in Slovenian)",
        "id": "Jakob Jakše, May 2024",
        "url": "https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=186121&dn=",
        "year": 2024,
        "kind": "report",
        "license": "university repository copy, cited not reproduced"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Modulus of elasticity, preview range",
      "value": 190,
      "value_high": 210,
      "bound": "range",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "heat_treatment": "not shown in the free preview",
        "temperature": "not shown in the free preview (the page has four temperature bands)"
      },
      "method": "Physical properties table of the free preview, Module d'elasticite row, printed as 190 — 210",
      "status": "ground",
      "source": "totalmateria-d2",
      "where": "Propriétés physiques table (free preview), Module d'elasticite row",
      "source_detail": {
        "title": "Total Materia: PROPRIETARY D2 Tool Steel (free preview)",
        "id": "Total Materia material 1350104, last updated 2022-03",
        "url": "https://www.totalmateria.com/fr/material/1350104",
        "kind": "database",
        "license": "Total Materia terms, cited not reproduced"
      }
    },
    {
      "benchmark": "density",
      "label": "Density, preview range",
      "value": 7.72,
      "value_high": 8,
      "bound": "range",
      "unit": "kg/dm3",
      "scope": "material",
      "conditions": {
        "heat_treatment": "not shown in the free preview",
        "temperature": "not shown in the free preview (the page has four temperature bands)"
      },
      "method": "Physical properties table of the free preview, Densité row, printed as 7.72 — 8 kg/dm³",
      "status": "ground",
      "source": "totalmateria-d2",
      "where": "Propriétés physiques table (free preview), Densité row",
      "source_detail": {
        "title": "Total Materia: PROPRIETARY D2 Tool Steel (free preview)",
        "id": "Total Materia material 1350104, last updated 2022-03",
        "url": "https://www.totalmateria.com/fr/material/1350104",
        "kind": "database",
        "license": "Total Materia terms, cited not reproduced"
      }
    },
    {
      "benchmark": "poissons_ratio",
      "label": "Poisson's ratio, preview range",
      "value": 0.27,
      "value_high": 0.3,
      "bound": "range",
      "unit": "-",
      "scope": "material",
      "conditions": {
        "heat_treatment": "not shown in the free preview",
        "temperature": "not shown in the free preview (the page has four temperature bands)"
      },
      "method": "Physical properties table of the free preview, Coefficient de Poisson row, printed as 0.27 — 0.3",
      "status": "ground",
      "source": "totalmateria-d2",
      "where": "Propriétés physiques table (free preview), Coefficient de Poisson row",
      "source_detail": {
        "title": "Total Materia: PROPRIETARY D2 Tool Steel (free preview)",
        "id": "Total Materia material 1350104, last updated 2022-03",
        "url": "https://www.totalmateria.com/fr/material/1350104",
        "kind": "database",
        "license": "Total Materia terms, cited not reproduced"
      }
    },
    {
      "benchmark": "density",
      "label": "Relative density, typical value",
      "value": 7.85,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "heat_treatment": "not stated; ground flat stock",
        "basis": "typical value, not a specification, as printed",
        "unit_in_source": "relative density, printed with no unit"
      },
      "method": "Section 9, Physical and Chemical Properties, Relative density row, printed as 7.85",
      "status": "ground",
      "source": "ssk-sds-d2",
      "where": "Section 9, Relative density",
      "source_detail": {
        "title": "Steel Service Krefeld (USA) Inc.: safety data sheet, precision ground flat stock of tool steel 1.2379 (AISI D 2), rev 0",
        "id": "16 March 2021",
        "url": "https://www.zoro.com/static/cms/enhanced_pdf/Steel%20Service%20Krefeld%20USA%20Inc_SafetyxxDataxxSheetxxGroundxxFlatxxStockxxD2xx97e26f.pdf",
        "year": 2021,
        "kind": "datasheet",
        "license": "supplier safety data sheet, linked not reproduced"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Atmosphere and humidity (general, no test given)",
      "headline": "D2 is not stainless: its corrosion resistance is below that of stainless steel (Wikipedia).",
      "effect": "Wikipedia says that certain D-type tool steels, with 10 to 13 percent chromium, are often considered stainless or semi-stainless, but their corrosion resistance is less than stainless steel, because most of the chromium and carbon are precipitated as carbides. The SDS says the stock is usually slightly oil coated to protect it from rust. No numeric corrosion rate for D2 was read in this run.",
      "rating": "unknown",
      "conditions": {
        "basis": "qualitative statements, no test conditions"
      },
      "source": "wikipedia-tool-steel",
      "where": "Tool steel article, D-series paragraph; SDS section 1 for the oil coating"
    },
    {
      "environment": "Strong acids (listed as incompatible)",
      "headline": "The SDS lists strong acids as incompatible with the stock.",
      "effect": "Section 10 of the Steel Service Krefeld SDS gives strong acids as the incompatible product. It gives no concentration, temperature or corrosion rate.",
      "rating": "unknown",
      "conditions": {
        "basis": "SDS section 10, incompatible products; no test conditions"
      },
      "source": "ssk-sds-d2",
      "where": "Section 10, Stability and Reactivity"
    },
    {
      "environment": "Nitriding or nitrocarburizing of the surface",
      "headline": "Nitriding gives a hard surface layer that Uddeholm says also increases corrosion resistance.",
      "effect": "Uddeholm says nitriding gives a hard surface layer that is very resistant to wear and erosion, and also increases corrosion resistance. The sheet gives surface hardness after nitriding at 525 C (about 1250 HV1) and nitrocarburizing at 570 C for 2 hours (about 950 HV1), but no corrosion test.",
      "rating": "unknown",
      "conditions": {
        "basis": "statement in the nitriding section; no corrosion test",
        "heat_treatment": "nitrided or nitrocarburized, hardened and tempered base"
      },
      "source": "uddeholm-sverker21",
      "where": "Page 5, Nitriding and nitrocarburizing"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "Steel Service Krefeld's SDS for D2 ground flat stock (16 March 2021) treats the stock as an article under REACH and says it is not hazardous as supplied. Cutting, milling or grinding can make dust or fumes that may be hazardous if inhaled.",
        "ghs": [],
        "source": "ssk-sds-d2",
        "where": "Section 2, Potential Hazards, General Statement; Section 15, Regulatory Information"
      },
      {
        "text": "Fumes or dust from cutting, milling or grinding may cause irritation, difficulty breathing or allergic skin reactions. The SDS adds that fumes, mists or dusts from processing may be carcinogenic if inhaled over a long period.",
        "ghs": [],
        "source": "ssk-sds-d2",
        "where": "Section 4, First Aid Measures; Section 11, Toxicological Information"
      },
      {
        "text": "The stock is nonflammable and there is no explosion hazard in a fire. The SDS gives no GHS classification for the stock.",
        "ghs": [],
        "source": "ssk-sds-d2",
        "where": "Section 5, Fire Fighting Measures; Section 9, Flammability"
      }
    ],
    "failure_risks": [
      {
        "mode": "Softening after high-temperature tempering",
        "trigger": "Tempering at 550 C or above",
        "consequence": "In the tempering curve cited by the thesis, hardness falls from 56 HRC at 550 C to 51 HRC at 600 C and 35 HRC at 700 C.",
        "severity": "moderate",
        "source": "thesis-d2-tempering",
        "where": "Section 2.1.4.3, Table 2.3"
      },
      {
        "mode": "Cracking or chipping under impact or bending",
        "trigger": "Impact loads, bending stresses or thick, hard work material",
        "consequence": "Uddeholm says the grade has rather limited cracking resistance and is not the choice where the risk of chipping or cracking is high.",
        "severity": "moderate",
        "source": "uddeholm-sverker21",
        "where": "Page 2, Properties profile and Applications"
      },
      {
        "mode": "Cracking during sub-zero treatment",
        "trigger": "Sub-zero treatment of tools with intricate shapes",
        "consequence": "Uddeholm warns that avoiding intricate shapes is needed because of the risk of cracking. Sub-zero treatment adds 1 to 3 HRC.",
        "severity": "moderate",
        "source": "uddeholm-sverker21",
        "where": "Page 5, Sub-zero treatment"
      },
      {
        "mode": "Decarburization and oxidation during hardening",
        "trigger": "Hardening without protecting the part",
        "consequence": "Uddeholm says the part must be protected against decarburization and oxidation during hardening.",
        "severity": "low",
        "source": "uddeholm-sverker21",
        "where": "Page 4, Hardening"
      },
      {
        "mode": "Lower hardness in real tools",
        "trigger": "Actual tool size and heat-treatment parameters",
        "consequence": "Uddeholm says lower hardness than the tempering curves can be expected in tools and dies, because of actual tool size and heat-treatment parameters.",
        "severity": "low",
        "source": "uddeholm-sverker21",
        "where": "Page 4, note under the tempering graphs"
      }
    ],
    "side_effects": [],
    "handling": [
      {
        "text": "Soft anneal at 850 C, cool in the furnace at 10 C per hour to 650 C, then cool freely in air.",
        "source": "uddeholm-sverker21",
        "where": "Page 4, Soft annealing"
      },
      {
        "text": "Stress relieve at 650 C for 2 hours after rough machining, cool slowly to 500 C, then cool freely in air.",
        "source": "uddeholm-sverker21",
        "where": "Page 4, Stress-relieving"
      },
      {
        "text": "Preheat at 650 to 750 C. Austenitize at 990 to 1080 C, usually 1000 to 1040 C, with soaking times of 30 to 60 minutes in the hardening table.",
        "source": "uddeholm-sverker21",
        "where": "Page 4, Hardening"
      },
      {
        "text": "Quench in oil (very simple geometries only), in vacuum with high-speed gas, in forced air or gas, or in a martempering bath or fluidized bed at 180 to 500 C, then cool in air.",
        "source": "uddeholm-sverker21",
        "where": "Page 4, Quenching media"
      },
      {
        "text": "Temper as soon as the tool reaches 50 to 70 C. Temper twice with intermediate cooling to room temperature, at no less than 180 C, holding at least 2 hours.",
        "source": "uddeholm-sverker21",
        "where": "Page 4, Tempering and note"
      },
      {
        "text": "Total Materia's preview gives 232 C for the best combination of toughness and hardness and 371 C for more ductility at some loss of hardness. A double temper uses a second temper 13.8 C (25 F) below the first.",
        "source": "totalmateria-d2",
        "where": "Traitement thermique (free preview), Tempering paragraph"
      },
      {
        "text": "Sub-zero treat at -70 to -80 C for 3 to 4 hours immediately after quenching, then temper, for maximum dimensional stability. Avoid intricate shapes.",
        "source": "uddeholm-sverker21",
        "where": "Page 5, Sub-zero treatment"
      },
      {
        "text": "For EDM in the hardened and tempered state, give an extra temper about 25 C below the previous tempering temperature.",
        "source": "uddeholm-sverker21",
        "where": "Page 7, Electrical discharge machining"
      },
      {
        "text": "Weld at a working temperature of 200 to 250 C. Matching consumables are needed if the tool will be polished or photo-etched.",
        "source": "uddeholm-sverker21",
        "where": "Page 7, Welding"
      },
      {
        "text": "Ventilate well during machining. Wear an FFP 2 or FFP 3 respirator (EN 149) for welding or burning, and safety glasses for cutting, milling or grinding.",
        "source": "ssk-sds-d2",
        "where": "Section 8, Limitation and Monitoring of Exposure"
      },
      {
        "text": "Avoid dust particles during machining, and avoid sharp edges or heated material.",
        "source": "ssk-sds-d2",
        "where": "Section 7, Handling and Storage"
      }
    ],
    "mitigations": [
      {
        "text": "Nitriding at 525 C or nitrocarburizing at 570 C gives a hard surface layer. Uddeholm says nitriding is very resistant to wear and erosion and increases corrosion resistance.",
        "source": "uddeholm-sverker21",
        "where": "Page 5, Nitriding and nitrocarburizing"
      },
      {
        "text": "Sub-zero treatment followed by tempering adds 1 to 3 HRC.",
        "source": "uddeholm-sverker21",
        "where": "Page 5, Sub-zero treatment"
      },
      {
        "text": "Use the tempering graphs for target hardness, but expect lower hardness in real tools. The Uddeholm curves are for 15 x 15 x 40 mm samples cooled in forced air.",
        "source": "uddeholm-sverker21",
        "where": "Page 4, Tempering graph note"
      }
    ]
  },
  "uses": [
    {
      "application": "mechanisms",
      "device": "Blanking, fine-blanking, punching, cropping, shearing and trimming tools",
      "example": "Uddeholm's cutting table gives tool hardness of 60 to 62 HRC for material under 3 mm thick and 58 to 60 HRC for 3 to 6 mm, with work material under 180 HB; lower hardness is printed for harder work material.",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Applications, cutting table"
    },
    {
      "application": "mechanisms",
      "device": "Thread-rolling dies and cold-extrusion dies",
      "example": "Uddeholm's forming table lists thread-rolling dies at 58 to 62 HRC and cold-extrusion dies at 58 to 60 HRC.",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Forming table, rows Cold extrusion dies and Thread-rolling dies"
    },
    {
      "application": "mechanisms",
      "device": "Shear blades, planer blades and industrial cutting tools",
      "example": "Wikipedia says D2 is widely used for shear blades, planer blades and industrial cutting tools, and sometimes for knife blades.",
      "source": "wikipedia-tool-steel",
      "where": "Tool steel article, D2 row of the composition table"
    },
    {
      "application": "mechanisms",
      "device": "Dies for moulding ceramics, bricks, tiles and grinding wheels, and plastic moulds for abrasive polymers",
      "example": "Uddeholm lists these dies at 58 to 62 HRC. Dörrenberg lists plastic moulds for abrasive polymers among the applications of its 1.2379 grade.",
      "source": "uddeholm-sverker21",
      "where": "Page 3, Forming table, dies for moulding row"
    }
  ],
  "supply": [
    {
      "subject": "Chromium",
      "abundance": "World resources are greater than 12 billion tons of shipping-grade chromite, and 95 percent of world chromium resources are in Kazakhstan and southern Africa. US net import reliance was 79 percent of apparent consumption in 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
        },
        {
          "country": "India",
          "share_percent": 5.9,
          "year": 2025
        },
        {
          "country": "Brazil",
          "share_percent": 3.9,
          "year": 2025
        },
        {
          "country": "Zimbabwe",
          "share_percent": 3.9,
          "year": 2025
        },
        {
          "country": "Finland",
          "share_percent": 3.7,
          "year": 2025
        }
      ],
      "critical_lists": [
        {
          "list": "USGS 2025 List of Critical Minerals (chromium, used in stainless steel)",
          "listed": true
        }
      ],
      "recycling": "In 2025, recycled chromium in reported stainless-steel scrap receipts accounted for 21 percent of apparent consumption.",
      "substitutes": [
        "Chromium has no substitute in stainless steel, the leading end use, or in superalloys, the major strategic end use (USGS 2026)."
      ],
      "source": "usgs-mcs2026-chromium",
      "where": "Salient Statistics, net import reliance 2025e; World Mine Production and Reserves, mine production 2025e in thousand t, gross weight: South Africa 23,000, Turkey 9,000, Kazakhstan 7,000, India 3,000, Brazil 2,000, Zimbabwe 2,000, Finland 1,900, world total 51,000 (rounded); shares calculated by Space Mushroom as printed tonnage over 51,000 t; World Resources; Substitutes; Recycling. List status from usgs-critical-2025 (read with WebFetch in this run)"
    },
    {
      "subject": "Molybdenum",
      "abundance": "World reserves were 17,000 thousand t. Identified resources are about 5.4 million t in the United States and about 20 million t in the rest of the world. Molybdenum is used principally as an alloying agent in cast iron, steel and superalloys (USGS 2026).",
      "producers": [
        {
          "country": "China",
          "share_percent": 37.3,
          "year": 2025
        },
        {
          "country": "Chile",
          "share_percent": 16.2,
          "year": 2025
        },
        {
          "country": "United States",
          "share_percent": 15.4,
          "year": 2025
        },
        {
          "country": "Peru",
          "share_percent": 15,
          "year": 2025
        },
        {
          "country": "Mexico",
          "share_percent": 6.5,
          "year": 2025
        }
      ],
      "critical_lists": [
        {
          "list": "USGS 2025 List of Critical Minerals",
          "listed": false
        }
      ],
      "recycling": "Molybdenum recycled as part of new and old steel and other scrap may be as much as 30 percent of the apparent supply (USGS 2026).",
      "substitutes": [
        "There is little substitution for molybdenum in steels and cast irons. Potential substitutes include boron, chromium, niobium and vanadium in alloy steels, and tungsten in tool steels (USGS 2026)."
      ],
      "source": "usgs-mcs2026-molybdenum",
      "where": "Domestic Production and Use; World Mine Production and Reserves, mine production 2025e in metric tons of molybdenum content: China 97,000, Chile 42,000, United States 40,000, Peru 39,000, Mexico 17,000, world total 260,000 (rounded); shares calculated by Space Mushroom as printed tonnage over 260,000 t; Reserves column; World Resources; Substitutes; Recycling. List status from usgs-critical-2025 (read with WebFetch in this run; the page summary names no molybdenum entry)"
    },
    {
      "subject": "Vanadium",
      "abundance": "World resources of vanadium exceed 63 million tons, and world reserves were 21,000 thousand t (rounded). More than 90 percent of reported domestic consumption in 2025 was metallurgical, mainly as an alloying agent for iron and steel. US net import reliance was 41 percent of apparent consumption in 2025e.",
      "producers": [
        {
          "country": "China",
          "share_percent": 74.5,
          "year": 2025
        },
        {
          "country": "Russia",
          "share_percent": 19.1,
          "year": 2025
        },
        {
          "country": "Brazil",
          "share_percent": 4.8,
          "year": 2025
        },
        {
          "country": "South Africa",
          "share_percent": 4.5,
          "year": 2025
        }
      ],
      "critical_lists": [
        {
          "list": "USGS 2025 List of Critical Minerals (vanadium, used to strengthen iron and steel)",
          "listed": true
        }
      ],
      "recycling": "Recycling of vanadium is mainly associated with reprocessing vanadium catalysts into new catalysts (USGS 2026).",
      "substitutes": [
        "Steels with other combinations of alloying elements can be substituted for vanadium steels. Manganese, molybdenum, niobium, titanium and tungsten are to some degree interchangeable with vanadium as alloying elements in steel (USGS 2026)."
      ],
      "source": "usgs-mcs2026-vanadium",
      "where": "Domestic Production and Use; Salient Statistics, net import reliance 2025e; World Mine Production and Reserves, mine production 2025e in metric tons of vanadium content: China 82,000, Russia 21,000, Brazil 5,300, South Africa 5,000, world total 110,000 (rounded). The printed national figures add to about 113,300 t, so the shares below, calculated by Space Mushroom over the printed total, sum to more than 100 percent. Reserves column; World Resources; Substitutes; Recycling. List status from usgs-critical-2025 (read with WebFetch in this run)"
    }
  ],
  "media": [],
  "documents": [
    {
      "title": "Uddeholm Sverker 21 technical datasheet (AISI D2, W.-Nr. 1.2379), edition 13, 04.2019",
      "type": "datasheet",
      "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
      "year": 2019
    },
    {
      "title": "Dörrenberg Edelstahl datasheet 1.2379 X153CrMoV12 (English)",
      "type": "datasheet",
      "url": "https://doerrenberg.de/fileadmin/special_steel/files/pdf_en_products_neues_Design/1.2379_en.pdf"
    },
    {
      "title": "Steel Service Krefeld (USA) safety data sheet, precision ground flat stock of tool steel 1.2379 (AISI D 2), rev 0, 16 March 2021 (copy on zoro.com)",
      "type": "sds",
      "url": "https://www.zoro.com/static/cms/enhanced_pdf/Steel%20Service%20Krefeld%20USA%20Inc_SafetyxxDataxxSheetxxGroundxxFlatxxStockxxD2xx97e26f.pdf",
      "year": 2021
    },
    {
      "title": "Total Materia: PROPRIETARY D2 Tool Steel (free preview, last updated 2022-03)",
      "type": "database",
      "url": "https://www.totalmateria.com/fr/material/1350104"
    },
    {
      "title": "Določanje popustnih karakteristik orodnega jekla D2 (tempering characteristics of D2 tool steel), bachelor's thesis, University of Ljubljana, May 2024",
      "type": "report",
      "url": "https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=186121&dn=",
      "year": 2024
    },
    {
      "title": "Estudo da resistência ao desgaste de aço VD2 com diferentes revenimentos (ABM Proceedings, wear of D2 with different tempering, English abstract)",
      "type": "paper",
      "url": "https://abmproceedings.com.br/en/article/estudo-da-resistncia-ao-desgaste-de-ao-vd2-com-diferentes-revenimentos"
    },
    {
      "title": "USGS Mineral Commodity Summaries 2026: Chromium",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf",
      "year": 2026
    },
    {
      "title": "USGS Mineral Commodity Summaries 2026: Molybdenum",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-molybdenum.pdf",
      "year": 2026
    },
    {
      "title": "USGS Mineral Commodity Summaries 2026: Vanadium",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-vanadium.pdf",
      "year": 2026
    },
    {
      "title": "USGS: About the 2025 List of Critical Minerals",
      "type": "report",
      "url": "https://www.usgs.gov/programs/mineral-resources-program/science/about-2025-list-critical-minerals",
      "year": 2025
    }
  ],
  "gaps": [
    "No numeric wear rate or volume loss for D2 was read in this run. The ABM pin-on-disc study gives its test conditions and a qualitative result in the English abstract; its full text was not reached, and the download link is a page, not a PDF.",
    "No numeric corrosion rate for D2 was read. The 2020 Al-Qawabah et al. paper on D2 and O1 in 0.1 M HCl (Materiali in tehnologije 54(6), 785-790) was located through its dLib record, but the article text returned an HTML page, so no value from it is used.",
    "Melting point is not recorded as a property. The SDS prints it as 1.530 C with a period as the thousands separator, which the source check cannot match to 1530, and no other fetched page gives a melting point.",
    "Dörrenberg's thermal expansion (10,5 to 13,0 x 10-6 per K, from 20 to 100 C through 20 to 400 C) and thermal conductivity (16,7 W/mK at 20 C, 20,5 at 350 C, 24,2 at 700 C) are printed with decimal commas, so they are not recorded as values. They disagree with Uddeholm (20.0 W/mK at 20 C; 11.2 to 12.3 ppm/K at 20 to 200 C).",
    "The thesis's own tempered samples were softer than its cited curve: its Table 4.1 gives 53,7 HRC after 2 x 2 h at 200 C in oil, against 61 HRC in Table 2.3. Those values carry decimal commas and are not recorded. The hardening temperature behind the cited curve is not stated in its table.",
    "The tempering graphs in the Uddeholm sheet and the tempering diagram in the Dörrenberg datasheet are images without printed values, so they were not read as numbers.",
    "Composition differs by supplier. Uddeholm typical analysis: 11.3 Cr, 0.8 Mo, 0.8 V. Dörrenberg: 12.00 Cr, 0.80 Mo, 0.90 V. Thesis: 12.00 Cr, 1.00 Mo, 0.85 V. Wikipedia: 11.0 to 13.0 Cr, 0.9 Mo, 1.0 V. The recipe uses the SDS ranges; the ASTM A681 and EN ISO 4957 texts were not reached.",
    "Density differs by source: 7700 kg/m3 at 20 C (Uddeholm, hardened and tempered), 7.85 (SDS typical value) and 7.72 to 8 kg/dm3 (Total Materia preview).",
    "Toughness wording differs. Dörrenberg says good toughness; Uddeholm says rather limited cracking resistance; Wikipedia says not as tough as lower-alloyed steels. This profile reports each as printed.",
    "Total Materia shows only a free preview. Its temperature bands and heat-treatment detail (205 property entries) need registration, so its E, density and Poisson ranges carry no condition.",
    "UNS T30402 and JIS SKD 11 come from the Total Materia cross-reference table only; no UNS, ASTM or JIS G4404 text was read directly. Some of its equivalents are marked implicit there.",
    "Critical-mineral lists come from the USGS 2025 list page, which refused the curl request (403) and was read with WebFetch. The membership reading is the page summary's; the list itself was not read as raw text.",
    "The USGS vanadium world total (110,000 t, 2025e) is smaller than the sum of the printed national figures (about 113,300 t), so vanadium shares sum to more than 100 percent when calculated over the printed total.",
    "No flight, space, vacuum, radiation, cryogenic or hydrogen data for D2 were read. The uses are terrestrial tooling, and the application slug mechanisms is the closest fit in the site taxonomy.",
    "No safety data sheet from a D2 steel mill was read. The SDS is from a stock distributor for ground flat stock (2021) and gives no GHS classification; the composition of welding fumes is not sourced.",
    "The thesis cites reference 6 for its physical data and tempering table. That reference was not identified, so those values are recorded as printed by the thesis.",
    "Property names not in property-canon: hardness_rockwell_c, hardness_brinell, compressive_yield_strength, surface_hardness_hv and case_depth. identity.designations is not in the site schema, so the site will not display it until the schema is extended."
  ],
  "story": {
    "why": "AISI D2 (EN 1.2379, X153CrMoV12) is a high-carbon, 12 percent chromium steel. Its many hard carbides give very high abrasive and adhesive wear resistance, and Uddeholm calls it the bulk grade for cold-work tooling. The trade-off is toughness: the Uddeholm sheet says it has rather limited cracking resistance. Hardness and toughness depend on the heat treatment, so each value in this profile carries its own condition.",
    "uses": [
      {
        "where": "Blanking and trimming tools",
        "line": "Uddeholm lists blanking, fine-blanking, punching, cropping, shearing and trimming tools in its cutting table, with tool hardness of 54 to 62 HRC depending on material thickness and work-material hardness."
      },
      {
        "where": "Thread-rolling and cold-extrusion dies",
        "line": "Uddeholm lists thread-rolling dies at 58 to 62 HRC and cold-extrusion dies at 58 to 60 HRC."
      },
      {
        "where": "Shear, planer and cutting blades",
        "line": "Wikipedia says D2 is widely used for shear blades, planer blades and industrial cutting tools, and sometimes for knife blades."
      }
    ],
    "can_do": [
      {
        "label": "Hardness",
        "line": "Hardening from 990 to 1030 C gives about 63 to 65 HRC before tempering (Uddeholm). Tempering then sets the working hardness: the thesis curve gives 61 HRC after 200 C and 51 HRC after 600 C.",
        "scope": "material"
      },
      {
        "label": "Stiffness",
        "line": "The modulus of elasticity is about 210 GPa at 20 C, falling to about 180 GPa at 400 C (Uddeholm).",
        "scope": "material"
      },
      {
        "label": "Compressive strength",
        "line": "Compressive yield strength is about 2200 MPa at 62 HRC and about 1650 MPa at 50 HRC (Uddeholm, approximate values).",
        "scope": "material"
      },
      {
        "label": "Wear",
        "line": "Very high abrasive and adhesive wear resistance from a high volume of hard carbides (Dörrenberg). Uddeholm rates its abrasive wear resistance as very good.",
        "scope": "material"
      },
      {
        "label": "Surface hardening",
        "line": "Nitriding at 525 C gives about 1250 HV1 at the surface, and nitrocarburizing at 570 C for 2 hours gives about 950 HV1 (Uddeholm).",
        "scope": "material"
      },
      {
        "label": "Dimensional stability",
        "line": "The Dörrenberg datasheet calls it very good in dimensional stability, and Uddeholm says it hardens through in all standard sizes.",
        "scope": "material"
      }
    ],
    "compare": "Among the datasheets for this grade, the modulus agrees: about 210 GPa at 20 C in Uddeholm and 190 to 210 GPa in the Total Materia preview. Density is 7700 kg/m3 in Uddeholm, 7.85 in the SDS typical value and 7.72 to 8 kg/dm3 in the Total Materia preview. Thermal expansion and conductivity differ between datasheets, so quote the source with each value. Toughness wording also differs: Dörrenberg says good toughness, Uddeholm says rather limited cracking resistance, and Wikipedia says D2 is not as tough as lower-alloyed steels.",
    "compare_rows": [
      {
        "label": "Stiffness",
        "benchmark": "elastic_modulus",
        "scope": "material"
      },
      {
        "label": "Density",
        "benchmark": "density",
        "scope": "material"
      },
      {
        "label": "Compressive strength",
        "benchmark": "compressive_yield_strength",
        "scope": "material"
      }
    ],
    "handling": [
      "Soft anneal at 850 C, cool in the furnace at 10 C per hour to 650 C, then air cool.",
      "Stress relieve at 650 C for 2 hours after rough machining.",
      "Preheat at 650 to 750 C, then harden from 990 to 1080 C, usually 1000 to 1040 C.",
      "Quench in oil only for very simple shapes; vacuum with high-speed gas, forced air or gas, and martempering at 180 to 500 C are the other options.",
      "Temper twice, at no less than 180 C, holding at least 2 hours each time.",
      "Protect the part against decarburization and oxidation during hardening.",
      "For EDM in the hardened and tempered state, temper again about 25 C below the previous tempering temperature.",
      "Wear an FFP 2 or FFP 3 respirator (EN 149) for welding or burning, and ventilate well during machining (SDS)."
    ],
    "good_for": [
      "Blanking, punching and trimming tools where abrasive wear limits tool life (Uddeholm).",
      "Thread-rolling and cold-extrusion dies at 58 to 62 HRC (Uddeholm).",
      "Shear blades, planer blades and industrial cutting tools (Wikipedia)."
    ],
    "watch_out": [
      "Toughness: rather limited cracking resistance (Uddeholm), and not as tough as lower-alloyed steels (Wikipedia).",
      "Corrosion: not stainless. Wikipedia says its corrosion resistance is less than stainless steel, and the SDS lists strong acids as incompatible.",
      "Tempering: in the thesis curve, hardness falls from 56 HRC at 550 C to 35 HRC at 700 C."
    ],
    "verdict": "AISI D2 is the bulk cold-work steel for wear-critical tooling. It trades toughness and corrosion resistance for hardness and wear resistance. Quote the heat-treatment condition with every value, and avoid it where chipping or impact is the main risk.",
    "recipe": {
      "line": "AISI D2 is an iron-based steel with about 1.5 percent carbon and 12 percent chromium, with molybdenum and vanadium as the other alloying additions. The SDS prints the composition ranges used here: carbon 1.40 to 1.60 percent, chromium 11.00 to 13.00 percent, molybdenum 0.70 to 1.20 percent, vanadium 0.50 to 1.10 percent, silicon and manganese 0.10 to 0.60 percent each, and phosphorus and sulphur 0.00 to 0.03 percent. Heat treatment, not composition alone, sets the hardness.",
      "parts": [
        {
          "name": "Iron",
          "symbol": "Fe",
          "role": "Matrix of the steel. The SDS lists iron as the base.",
          "share_note": "balance (the rest)"
        },
        {
          "name": "Carbon",
          "symbol": "C",
          "role": "Part of the high volume of hard carbides that gives the steel its wear resistance (Dörrenberg).",
          "share_percent": 1.4,
          "share_high": 1.6,
          "source": "ssk-sds-d2",
          "where": "Section 3, Chemical composition"
        },
        {
          "name": "Silicon",
          "symbol": "Si",
          "role": "Small addition listed in the composition.",
          "share_percent": 0.1,
          "share_high": 0.6,
          "source": "ssk-sds-d2",
          "where": "Section 3, Chemical composition"
        },
        {
          "name": "Manganese",
          "symbol": "Mn",
          "role": "Small addition listed in the composition.",
          "share_percent": 0.1,
          "share_high": 0.6,
          "source": "ssk-sds-d2",
          "where": "Section 3, Chemical composition"
        },
        {
          "name": "Chromium",
          "symbol": "Cr",
          "role": "About 12 percent. Uddeholm calls it a 12 percent chromium steel; chromium is tied up in carbides, so the steel is not stainless (Wikipedia).",
          "share_percent": 11,
          "share_high": 13,
          "source": "ssk-sds-d2",
          "where": "Section 3, Chemical composition"
        },
        {
          "name": "Molybdenum",
          "symbol": "Mo",
          "role": "Alloying addition, listed with vanadium in the Uddeholm sheet.",
          "share_percent": 0.7,
          "share_high": 1.2,
          "source": "ssk-sds-d2",
          "where": "Section 3, Chemical composition"
        },
        {
          "name": "Vanadium",
          "symbol": "V",
          "role": "Alloying addition, listed with molybdenum in the Uddeholm sheet.",
          "share_percent": 0.5,
          "share_high": 1.1,
          "source": "ssk-sds-d2",
          "where": "Section 3, Chemical composition"
        },
        {
          "name": "Phosphorus",
          "symbol": "P",
          "role": "Impurity held low.",
          "share_percent": 0,
          "share_high": 0.03,
          "share_note": "printed as 0.00 to 0.03",
          "source": "ssk-sds-d2",
          "where": "Section 3, Chemical composition"
        },
        {
          "name": "Sulphur",
          "symbol": "S",
          "role": "Impurity held low.",
          "share_percent": 0,
          "share_high": 0.03,
          "share_note": "printed as 0.00 to 0.03",
          "source": "ssk-sds-d2",
          "where": "Section 3, Chemical composition"
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "The SDS says the stock is not hazardous as supplied. The risk comes from dust and fumes when it is cut, ground or welded.",
        "points": [
          {
            "label": "Stock as supplied",
            "line": "The SDS treats the ground flat stock as an article under REACH and says it is not hazardous as supplied. It is nonflammable."
          },
          {
            "label": "Processing",
            "line": "Cutting, milling, grinding or welding can make dust or fumes that may be hazardous if inhaled. The SDS says fumes and dusts from processing may be carcinogenic if inhaled over a long time."
          },
          {
            "label": "Respirator",
            "line": "For welding or burning, the SDS calls for an FFP 2 or FFP 3 respirator (EN 149) and face shields."
          }
        ],
        "level": 1,
        "verdict": "Dust and fumes from processing are the watch point"
      },
      {
        "title": "Heat treatment",
        "lead": "The same steel can be soft, hard or tough depending on the cycle. These results come from datasheets and a thesis, not from field use.",
        "points": [
          {
            "label": "Tempering",
            "line": "In the tempering curve cited by the thesis, hardness falls from 61 HRC at 200 C to 56 HRC at 550 C, 51 HRC at 600 C and 35 HRC at 700 C."
          },
          {
            "label": "Hardening",
            "line": "Hardening from 990 to 1080 C gave about 63 to 65 HRC before tempering in the Uddeholm table."
          },
          {
            "label": "Cracking",
            "line": "Uddeholm warns of limited cracking resistance and says intricate shapes that are sub-zero treated risk cracking."
          }
        ],
        "level": 2,
        "verdict": "Hardness and toughness follow the cycle"
      },
      {
        "title": "Corrosion",
        "lead": "D2 has about 12 percent chromium, but most of it is tied up in carbides, so it is not a stainless steel.",
        "points": [
          {
            "label": "Stainless?",
            "line": "Wikipedia says certain D-type tool steels are often considered stainless or semi-stainless, but their corrosion resistance is less than stainless steel."
          },
          {
            "label": "Acids",
            "line": "The SDS lists strong acids as incompatible with the stock."
          },
          {
            "label": "Storage",
            "line": "The SDS says the stock is usually slightly oil coated to protect it from rust."
          }
        ],
        "level": 2,
        "verdict": "Not stainless; the stock is oil coated"
      }
    ]
  },
  "updated": "2026-10-24",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 35,
    "unreachable": 4,
    "caveats": 4,
    "note": "Read by an AI assistant on 2026-10-24 from pages fetched in this run. Each value carries its heat-treatment or test state in conditions. Not reached: the Xometry datasheet (403), the dLib article text (HTML only), steeldata.info (empty) and the CROSBI wear record (empty). The USGS list page refused curl and was read with WebFetch."
  },
  "sources": {
    "uddeholm-sverker21": {
      "title": "Uddeholm Sverker 21 (AISI D2, W.-Nr. 1.2379), technical datasheet, Bohler-Uddeholm",
      "id": "Edition 13, 04.2019",
      "url": "https://uddeholm.com/app/uploads/sites/247/2024/09/Tech-Uddeholm-Sverker-21-EN.pdf",
      "year": 2019,
      "kind": "datasheet",
      "license": "supplier datasheet, cited not reproduced"
    },
    "doerrenberg-1-2379": {
      "title": "Dörrenberg Edelstahl: 1.2379 X153CrMoV12 datasheet (English, similar to AISI D2)",
      "id": "Material No. 1.2379, code X153CrMoV12",
      "url": "https://doerrenberg.de/fileadmin/special_steel/files/pdf_en_products_neues_Design/1.2379_en.pdf",
      "kind": "datasheet",
      "license": "supplier datasheet, cited not reproduced"
    },
    "ssk-sds-d2": {
      "title": "Steel Service Krefeld (USA) Inc.: safety data sheet, precision ground flat stock of tool steel 1.2379 (AISI D 2), rev 0",
      "id": "16 March 2021",
      "url": "https://www.zoro.com/static/cms/enhanced_pdf/Steel%20Service%20Krefeld%20USA%20Inc_SafetyxxDataxxSheetxxGroundxxFlatxxStockxxD2xx97e26f.pdf",
      "year": 2021,
      "kind": "datasheet",
      "license": "supplier safety data sheet, linked not reproduced"
    },
    "totalmateria-d2": {
      "title": "Total Materia: PROPRIETARY D2 Tool Steel (free preview)",
      "id": "Total Materia material 1350104, last updated 2022-03",
      "url": "https://www.totalmateria.com/fr/material/1350104",
      "kind": "database",
      "license": "Total Materia terms, cited not reproduced"
    },
    "thesis-d2-tempering": {
      "title": "Določanje popustnih karakteristik orodnega jekla D2 (Determining the tempering characteristics of D2 tool steel), bachelor's thesis, Faculty of Mechanical Engineering, University of Ljubljana (in Slovenian)",
      "id": "Jakob Jakše, May 2024",
      "url": "https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=186121&dn=",
      "year": 2024,
      "kind": "report",
      "license": "university repository copy, cited not reproduced"
    },
    "abm-vd2-wear": {
      "title": "Estudo da resistência ao desgaste de aço VD2 com diferentes revenimentos (ABM Proceedings), English abstract read",
      "id": "ABM Proceedings, article page",
      "url": "https://abmproceedings.com.br/en/article/estudo-da-resistncia-ao-desgaste-de-ao-vd2-com-diferentes-revenimentos",
      "kind": "paper",
      "license": "publisher page, cited not reproduced"
    },
    "wikipedia-tool-steel": {
      "title": "Tool steel (Wikipedia), D-series paragraph and D2 row of the composition table",
      "id": "en.wikipedia.org/wiki/Tool_steel",
      "url": "https://en.wikipedia.org/wiki/Tool_steel",
      "kind": "web",
      "license": "CC BY-SA 4.0 (Wikipedia)"
    },
    "usgs-mcs2026-chromium": {
      "title": "USGS Mineral Commodity Summaries 2026: Chromium",
      "id": "mcs2026-chromium, February 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    },
    "usgs-mcs2026-molybdenum": {
      "title": "USGS Mineral Commodity Summaries 2026: Molybdenum",
      "id": "mcs2026-molybdenum, February 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-molybdenum.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    },
    "usgs-mcs2026-vanadium": {
      "title": "USGS Mineral Commodity Summaries 2026: Vanadium",
      "id": "mcs2026-vanadium, February 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-vanadium.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    },
    "usgs-critical-2025": {
      "title": "USGS: About the 2025 List of Critical Minerals (final list)",
      "id": "2025 List of Critical Minerals",
      "url": "https://www.usgs.gov/programs/mineral-resources-program/science/about-2025-list-critical-minerals",
      "year": 2025,
      "kind": "web",
      "license": "public domain (USGS)"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/tool-steel-d2/"
}