{
  "spore": "profile",
  "id": "titanium-diboride",
  "spore_version": "0.2",
  "family": "carbide-nitride-boride-ceramics",
  "name": "Titanium diboride",
  "abbreviation": "TiB2",
  "role": "hard, electrically conductive ultra-high-temperature ceramic (boride)",
  "category": "ceramics",
  "type": "ultra-high-temperature-ceramics",
  "summary": "Titanium diboride is a hexagonal boride that is hard, stiff and electrically conductive. NIST's evaluated trend values for dense polycrystalline TiB2 (density 4.5 g/cm3, grain size 9 micrometres) give an elastic modulus of 565 GPa, a flexural strength of 400 MPa, a fracture toughness of 6.2 MPa·m1/2 and a Vickers hardness of 25 GPa at 20 degC, falling to 4.6 GPa at 1000 degC. A 2024 open-access review gives a melting point of 3225 degC, a hardness of 25 to 35 GPa, a thermal conductivity of 60 to 120 W/m·K and an oxidation resistance below 1200 degC. The sources disagree on flexural strength (400 MPa from NIST against 700 to 1000 MPa in the review), so both values are kept. Titanium, one of its two elements, is produced mostly in China and Japan (USGS 2026).\n",
  "best_for": "Hard, stiff, electrically conductive ceramic parts and wear surfaces, such as cathodes and cutting tools, where a melting point near 3225 degC matters more than oxidation resistance",
  "weakest_at": "Oxidation in air at high temperature (the review calls resistance inadequate, and B2O3 volatilises as the temperature rises, per Ozkan et al.) and brittleness (Weibull modulus of 11, NIST)",
  "identity": {
    "formula": "TiB2",
    "cas": "12045-63-5",
    "crystal_system": "hexagonal",
    "space_group": "P6/mmm",
    "designations": [],
    "source": "pubchem-tib2",
    "where": "PubChem CID 92028754 record (formula, synonyms and CAS 12045-63-5). Hexagonal P6/mmm from NIST Munro 2000, Figure 1 text."
  },
  "tags": {
    "environments": [],
    "stresses": [
      "extreme-heat"
    ],
    "applications": [
      "structures",
      "mechanisms"
    ]
  },
  "properties": [
    {
      "benchmark": "density",
      "label": "Crystal density, TiB2 (single crystal)",
      "value": 4.5,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "temperature": "20 degC",
        "basis": "single crystal, theoretical crystal density"
      },
      "method": "Density row of NIST Table 1, footnote d (single crystal). Not the polycrystalline density.",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Density row, 20 degC column",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "density",
      "label": "Density, TiB2 (review table)",
      "value": 4.5,
      "bound": "exact",
      "unit": "g/cm3",
      "scope": "material",
      "conditions": {
        "basis": "TiB2 column of the review's property table"
      },
      "method": "Table 1 of the 2024 review, Density row",
      "status": "ground",
      "source": "lv-tib2-2024",
      "where": "Table 1 (Properties of TiB2 and other important high-temperature ceramics), Density row, TiB2 column",
      "source_detail": {
        "title": "Lv X, Yin Z, Yang Z, Chen J et al., Review on the Development of Titanium Diboride Ceramics, Recent Progress in Materials 6(2), doi 10.21926/rpm.2402009",
        "url": "https://lidsen.com/journals/rpm/rpm-06-02-009",
        "kind": "paper",
        "license": "open access, CC BY (per the journal)"
      }
    },
    {
      "benchmark": "melting_point",
      "label": "Melting point, TiB2",
      "value": 3225,
      "bound": "exact",
      "unit": "degC",
      "scope": "material",
      "conditions": {
        "basis": "TiB2 column of the review's property table"
      },
      "method": "Table 1 of the 2024 review, Melting point row",
      "status": "ground",
      "source": "lv-tib2-2024",
      "where": "Table 1, Melting point row, TiB2 column",
      "source_detail": {
        "title": "Lv X, Yin Z, Yang Z, Chen J et al., Review on the Development of Titanium Diboride Ceramics, Recent Progress in Materials 6(2), doi 10.21926/rpm.2402009",
        "url": "https://lidsen.com/journals/rpm/rpm-06-02-009",
        "kind": "paper",
        "license": "open access, CC BY (per the journal)"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Elastic modulus, dense polycrystalline TiB2 (NIST trend value)",
      "value": 565,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "temperature": "20 degC",
        "basis": "trend value for density 4.5 plus or minus 0.1 g/cm3, grain size 9 plus or minus 1 micrometres, TiB2 at least 98 percent",
        "uncertainty": "5 percent relative standard uncertainty"
      },
      "method": "Mutually consistent trend values (NIST Table 1)",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Elastic modulus row, 20 degC column",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "elastic_modulus",
      "label": "Elastic modulus, TiB2 (review table)",
      "value": 500,
      "value_high": 560,
      "bound": "range",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "basis": "TiB2 column of the review's property table; temperature not stated"
      },
      "method": "Printed as 500-560 in Table 1 of the 2024 review",
      "status": "ground",
      "source": "lv-tib2-2024",
      "where": "Table 1, Elastic modulus row, TiB2 column",
      "source_detail": {
        "title": "Lv X, Yin Z, Yang Z, Chen J et al., Review on the Development of Titanium Diboride Ceramics, Recent Progress in Materials 6(2), doi 10.21926/rpm.2402009",
        "url": "https://lidsen.com/journals/rpm/rpm-06-02-009",
        "kind": "paper",
        "license": "open access, CC BY (per the journal)"
      }
    },
    {
      "benchmark": "shear_modulus",
      "label": "Shear modulus, dense polycrystalline TiB2 (NIST trend value)",
      "value": 255,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "temperature": "20 degC",
        "basis": "trend value, same material as the elastic modulus row"
      },
      "method": "Mutually consistent trend values (NIST Table 1)",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Shear modulus row, 20 degC column",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "bulk_modulus",
      "label": "Bulk modulus, dense polycrystalline TiB2 (NIST trend value)",
      "value": 240,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "temperature": "20 degC",
        "basis": "trend value, same material as the elastic modulus row"
      },
      "method": "Mutually consistent trend values (NIST Table 1)",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Bulk modulus row, 20 degC column",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "poissons_ratio",
      "label": "Poisson's ratio, dense polycrystalline TiB2 (NIST trend value)",
      "value": 0.108,
      "bound": "exact",
      "unit": "unitless",
      "scope": "material",
      "conditions": {
        "temperature": "20 degC"
      },
      "method": "Mutually consistent trend values (NIST Table 1)",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Poisson's ratio row",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "flexural_strength",
      "label": "Flexural strength, dense polycrystalline TiB2 (NIST trend value)",
      "value": 400,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "temperature": "20 degC",
        "basis": "trend value, same material as the elastic modulus row"
      },
      "method": "Mutually consistent trend values (NIST Table 1)",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Flexural strength row, 20 degC column",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "flexural_strength",
      "label": "Flexural strength, dense polycrystalline TiB2 at 1000 degC (NIST trend value)",
      "value": 459,
      "bound": "exact",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "temperature": "1000 degC",
        "basis": "trend value, same material as the elastic modulus row"
      },
      "method": "Mutually consistent trend values (NIST Table 1)",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Flexural strength row, 1000 degC column",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "flexural_strength",
      "label": "Flexural strength, TiB2 (review table)",
      "value": 700,
      "value_high": 1000,
      "bound": "range",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "basis": "TiB2 column of the review's property table; temperature and grade not stated"
      },
      "method": "Printed as 700-1000 in Table 1 of the 2024 review. Higher than the NIST trend value of 400 MPa; the sources do not explain the gap.",
      "status": "ground",
      "source": "lv-tib2-2024",
      "where": "Table 1, Flexural strength row, TiB2 column",
      "source_detail": {
        "title": "Lv X, Yin Z, Yang Z, Chen J et al., Review on the Development of Titanium Diboride Ceramics, Recent Progress in Materials 6(2), doi 10.21926/rpm.2402009",
        "url": "https://lidsen.com/journals/rpm/rpm-06-02-009",
        "kind": "paper",
        "license": "open access, CC BY (per the journal)"
      }
    },
    {
      "benchmark": "fracture_toughness",
      "label": "Fracture toughness, dense polycrystalline TiB2 (NIST trend value)",
      "value": 6.2,
      "bound": "exact",
      "unit": "MPa·m1/2",
      "scope": "material",
      "conditions": {
        "temperature": "20 degC",
        "basis": "trend value, same material as the elastic modulus row"
      },
      "method": "Mutually consistent trend values (NIST Table 1); Section 3.3 gives the grain-size dependence",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Fracture toughness row, 20 degC column",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "fracture_toughness",
      "label": "Fracture toughness, TiB2 (review table)",
      "value": 4,
      "value_high": 5,
      "bound": "range",
      "unit": "MPa·m1/2",
      "scope": "material",
      "conditions": {
        "basis": "TiB2 column of the review's property table; test method not stated"
      },
      "method": "Printed as 4-5 in Table 1 of the 2024 review",
      "status": "ground",
      "source": "lv-tib2-2024",
      "where": "Table 1, Fracture toughness row, TiB2 column",
      "source_detail": {
        "title": "Lv X, Yin Z, Yang Z, Chen J et al., Review on the Development of Titanium Diboride Ceramics, Recent Progress in Materials 6(2), doi 10.21926/rpm.2402009",
        "url": "https://lidsen.com/journals/rpm/rpm-06-02-009",
        "kind": "paper",
        "license": "open access, CC BY (per the journal)"
      }
    },
    {
      "benchmark": "hardness",
      "label": "Vickers hardness, dense polycrystalline TiB2 (NIST trend value)",
      "value": 25,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "temperature": "20 degC",
        "load": "5 N Vickers (footnote f)",
        "basis": "trend value, same material as the elastic modulus row"
      },
      "method": "Mutually consistent trend values (NIST Table 1), Vickers at 5 N load",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Hardness row, 20 degC column; footnote f",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "hardness",
      "label": "Vickers hardness, dense polycrystalline TiB2 at 500 degC (NIST trend value)",
      "value": 11,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "temperature": "500 degC",
        "load": "5 N Vickers"
      },
      "method": "Mutually consistent trend values (NIST Table 1)",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Hardness row, 500 degC column",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "hardness",
      "label": "Vickers hardness, dense polycrystalline TiB2 at 1000 degC (NIST trend value)",
      "value": 4.6,
      "bound": "exact",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "temperature": "1000 degC",
        "load": "5 N Vickers"
      },
      "method": "Mutually consistent trend values (NIST Table 1)",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Hardness row, 1000 degC column",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "hardness",
      "label": "Hardness, TiB2 (review table)",
      "value": 25,
      "value_high": 35,
      "bound": "range",
      "unit": "GPa",
      "scope": "material",
      "conditions": {
        "basis": "TiB2 column of the review's property table; test method not stated"
      },
      "method": "Printed as 25-35 in Table 1 of the 2024 review",
      "status": "ground",
      "source": "lv-tib2-2024",
      "where": "Table 1, Hardness row, TiB2 column",
      "source_detail": {
        "title": "Lv X, Yin Z, Yang Z, Chen J et al., Review on the Development of Titanium Diboride Ceramics, Recent Progress in Materials 6(2), doi 10.21926/rpm.2402009",
        "url": "https://lidsen.com/journals/rpm/rpm-06-02-009",
        "kind": "paper",
        "license": "open access, CC BY (per the journal)"
      }
    },
    {
      "benchmark": "weibull_modulus",
      "label": "Weibull modulus, TiB2 (NIST, three reported values)",
      "value": 11,
      "bound": "exact",
      "unit": "unitless",
      "scope": "material",
      "conditions": {
        "basis": "one of three reported values: 11 (sintered, 8 micrometre grain), 29 (hot pressed) and 8 (hot pressed, 15 micrometre grain)"
      },
      "method": "Weibull modulus row of NIST Table 1 with footnote i; the paper says reliable values need at least 30 specimens",
      "status": "ground",
      "note": "Three reported values (8, 11, 29) differ widely; 11 is the value printed in the table.",
      "source": "nist-munro-2000",
      "where": "Table 1, Weibull modulus row, footnote i; Section 3.2",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity, dense polycrystalline TiB2 (NIST trend value)",
      "value": 96,
      "bound": "exact",
      "unit": "W/m·K",
      "scope": "material",
      "conditions": {
        "temperature": "20 degC",
        "basis": "trend value, same material as the elastic modulus row"
      },
      "method": "Mutually consistent trend values (NIST Table 1), derived from thermal diffusivity and specific heat",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Thermal conductivity row, 20 degC column",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity, dense polycrystalline TiB2 at 1000 degC (NIST trend value)",
      "value": 78.1,
      "bound": "exact",
      "unit": "W/m·K",
      "scope": "material",
      "conditions": {
        "temperature": "1000 degC",
        "basis": "trend value, same material as the elastic modulus row"
      },
      "method": "Mutually consistent trend values (NIST Table 1)",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Thermal conductivity row, 1000 degC column",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity, TiB2 (review table)",
      "value": 60,
      "value_high": 120,
      "bound": "range",
      "unit": "W/m·K",
      "scope": "material",
      "conditions": {
        "basis": "TiB2 column of the review's property table; temperature and grade not stated"
      },
      "method": "Printed as 60-120 W m-1 K-1 in Table 1 of the 2024 review",
      "status": "ground",
      "note": "Wide range; the review's text repeats it as 60-120 W·(m·K)-1.",
      "source": "lv-tib2-2024",
      "where": "Table 1, Thermal conductivity row, TiB2 column",
      "source_detail": {
        "title": "Lv X, Yin Z, Yang Z, Chen J et al., Review on the Development of Titanium Diboride Ceramics, Recent Progress in Materials 6(2), doi 10.21926/rpm.2402009",
        "url": "https://lidsen.com/journals/rpm/rpm-06-02-009",
        "kind": "paper",
        "license": "open access, CC BY (per the journal)"
      }
    },
    {
      "benchmark": "specific_heat",
      "label": "Specific heat, dense polycrystalline TiB2 (NIST trend value)",
      "value": 617,
      "bound": "exact",
      "unit": "J/kg·K",
      "scope": "material",
      "conditions": {
        "temperature": "20 degC",
        "basis": "trend value, same material as the elastic modulus row"
      },
      "method": "Mutually consistent trend values (NIST Table 1)",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Specific heat row, 20 degC column",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "cte",
      "label": "Mean coefficient of thermal expansion, TiB2 (NIST trend value)",
      "value": 7.4,
      "bound": "exact",
      "unit": "10-6/K",
      "scope": "material",
      "conditions": {
        "temperature": "20 degC",
        "basis": "mean linear CTE, alpha m = (2 alpha a + alpha c) / 3, from the single-crystal axial values; reference state 20 degC"
      },
      "method": "Thermal expansion alpha m row of NIST Table 1 (footnote h). The paper prints 10 to the power -6 per K.",
      "status": "ground",
      "source": "nist-munro-2000",
      "where": "Table 1, Thermal expansion alpha m row, 20 degC column; footnote h",
      "source_detail": {
        "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
        "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
        "kind": "paper",
        "license": "public domain (NIST)"
      }
    },
    {
      "benchmark": "cte",
      "label": "Coefficient of thermal expansion, TiB2 (review table)",
      "value": 8.6,
      "bound": "exact",
      "unit": "10-6/K",
      "scope": "material",
      "conditions": {
        "basis": "TiB2 column of the review's property table; temperature not stated"
      },
      "method": "CTE row of Table 1 in the 2024 review, printed as 10-6 K-1",
      "status": "ground",
      "source": "lv-tib2-2024",
      "where": "Table 1, CTE row, TiB2 column",
      "source_detail": {
        "title": "Lv X, Yin Z, Yang Z, Chen J et al., Review on the Development of Titanium Diboride Ceramics, Recent Progress in Materials 6(2), doi 10.21926/rpm.2402009",
        "url": "https://lidsen.com/journals/rpm/rpm-06-02-009",
        "kind": "paper",
        "license": "open access, CC BY (per the journal)"
      }
    },
    {
      "benchmark": "electrical_resistivity",
      "label": "Electrical resistivity, TiB2 (review table)",
      "value": 9,
      "value_high": 15,
      "bound": "range",
      "unit": "uOhm·cm",
      "scope": "material",
      "conditions": {
        "basis": "TiB2 column of the review's property table; temperature not stated"
      },
      "method": "Printed as 9-15 with unit 10-6 Ohm·cm in Table 1 of the 2024 review; the same value in micro-ohm centimetres",
      "status": "ground",
      "source": "lv-tib2-2024",
      "where": "Table 1, Electrical resistivity row, TiB2 column",
      "source_detail": {
        "title": "Lv X, Yin Z, Yang Z, Chen J et al., Review on the Development of Titanium Diboride Ceramics, Recent Progress in Materials 6(2), doi 10.21926/rpm.2402009",
        "url": "https://lidsen.com/journals/rpm/rpm-06-02-009",
        "kind": "paper",
        "license": "open access, CC BY (per the journal)"
      }
    },
    {
      "benchmark": "oxidation_resistance_temp",
      "label": "Oxidation resistance limit, TiB2 (review table)",
      "value": 1200,
      "bound": "upper",
      "unit": "degC",
      "scope": "material",
      "conditions": {
        "atmosphere": "air (the review does not state the atmosphere)",
        "basis": "TiB2 column of the review's property table, printed as less than 1200"
      },
      "method": "Oxidation resistance row of Table 1 in the 2024 review. Not a rate or a test result.",
      "status": "ground",
      "note": "Custom property name; no oxidation-limit name in the canon file. The review's text calls oxidation resistance inadequate.",
      "source": "lv-tib2-2024",
      "where": "Table 1, Oxidation resistance row, TiB2 column",
      "source_detail": {
        "title": "Lv X, Yin Z, Yang Z, Chen J et al., Review on the Development of Titanium Diboride Ceramics, Recent Progress in Materials 6(2), doi 10.21926/rpm.2402009",
        "url": "https://lidsen.com/journals/rpm/rpm-06-02-009",
        "kind": "paper",
        "license": "open access, CC BY (per the journal)"
      }
    },
    {
      "benchmark": "particle_size_d50",
      "label": "Particle size D50, TiB2 powder grade D",
      "value": 3.5,
      "value_high": 6,
      "bound": "range",
      "unit": "micrometre",
      "scope": "material",
      "conditions": {
        "grade": "Grade D",
        "method_detail": "laser diffraction, ASTM C 1070 (Microtrac)"
      },
      "method": "Particle size distribution table, D50 row, grade D column (datasheet dated 2007)",
      "status": "ground",
      "note": "Custom property name. Powder property, not a bulk property.",
      "source": "hoganas-pd5123",
      "where": "Particle Size Distribution table, D50 row, Grade D",
      "source_detail": {
        "title": "Hoganas, Titanium Diboride Grades D, SE and F, datasheet PD-5123 (issue 5-31.07.2007)",
        "url": "https://www.hoganas.com/globalassets/downloads/stc/PD-5123.pdf",
        "kind": "datasheet",
        "license": "vendor datasheet, cited not reproduced"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Oxidizing air at 800 to 1200 degC (cyclic oxidation of cold-pressed pellets)",
      "headline": "TiO2 and B2O3 form; B2O3 volatilisation has a significant effect as the temperature rises.",
      "effect": "Ozkan et al. oxidised cold-pressed TiB2 pellets at 800 to 1200 degC for 5, 10, 15 and 20 h. XRD found TiO2 and B2O3 as oxidation products. The authors say volatilisation of B2O3 had a significant effect on oxidation as the temperature increased, and that their samples oxidised faster than values in the literature because of their porosity. The abstract gives no rate constants.",
      "rating": "moderate",
      "conditions": {
        "temperature": "800 to 1200 degC",
        "time": "5, 10, 15 and 20 h",
        "form": "cold-pressed pellets, porous"
      },
      "source": "ozkan-2017",
      "where": "Abstract (full text not read)"
    },
    {
      "environment": "Oxidizing air at 400 to 1000 degC (TiB2 films and coatings)",
      "headline": "Films lose oxidation resistance above 400 degC; between 650 and 1000 degC the scale is laminated TiO2 and glassy B2O3.",
      "effect": "Bahr et al. say the oxidation resistance of TiB2-based films is limited above 400 degC. Between 650 and 1000 degC the scale is a laminated structure of crystalline TiO2 and glassy, amorphous B2O3. This is a coatings study, so the numbers describe thin films, not bulk parts.",
      "rating": "moderate",
      "conditions": {
        "form": "TiB2-based films and coatings",
        "atmosphere": "air (per the paper's oxidation studies)"
      },
      "source": "bahr-2023",
      "where": "Introduction, paragraph on oxidation of TiB2 films"
    },
    {
      "environment": "Oxidation at high temperature, followed by room-temperature testing",
      "headline": "Strength of specimens oxidised at higher temperatures is lower at room temperature, but B2O3 can heal cracks up to about 1000 degC.",
      "effect": "NIST says crack healing by oxidation and formation of B2O3 may add to the strength rise with temperature up to about 1000 degC. Room-temperature strengths of specimens oxidised at higher temperatures appear to be diminished by oxidation.",
      "rating": "moderate",
      "conditions": {
        "temperature": "up to about 1000 degC for crack healing; above that for strength loss",
        "atmosphere": "oxidizing"
      },
      "source": "nist-munro-2000",
      "where": "Section 3.2 (Strength), paragraph on temperature dependence"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "PubChem aggregated GHS for titanium diboride (CID 92028754, signal word Warning): H302 harmful if swallowed, H312 harmful in contact with skin and H332 harmful if inhaled, each in 90.1 percent of the 218 company reports that gave hazard codes. 6.4 percent (15 of 233) of reports say it does not meet GHS hazard criteria.",
        "ghs": [
          "H302",
          "H312",
          "H332"
        ],
        "source": "pubchem-tib2",
        "where": "Safety and Hazards, GHS Classification"
      },
      {
        "text": "Supplier data (Hoganas grade D powder, 2007): the datasheet has no hazard section. No supplier safety data sheet with GHS classification was read in this run.",
        "ghs": [],
        "source": "hoganas-pd5123",
        "where": "Datasheet, whole document (no hazard section)"
      }
    ],
    "failure_risks": [
      {
        "mode": "Brittle fracture of dense ceramic",
        "trigger": "Tensile or bending load on a flaw",
        "consequence": "NIST trend values at 20 degC: flexural strength 400 MPa, fracture toughness 6.2 MPa·m1/2 and Weibull modulus 11, so strength varies from part to part",
        "severity": "moderate",
        "source": "nist-munro-2000",
        "where": "Table 1 (flexural strength, fracture toughness, Weibull modulus); Section 3.2"
      },
      {
        "mode": "Strength loss after high-temperature oxidation",
        "trigger": "Exposure to oxidizing air at high temperature",
        "consequence": "NIST says room-temperature strengths of specimens oxidised at higher temperatures are diminished; the review says oxidation resistance is inadequate for wide use",
        "severity": "moderate",
        "source": "nist-munro-2000",
        "where": "Section 3.2 (Strength), last paragraph before Table 1"
      }
    ],
    "side_effects": [],
    "handling": [
      {
        "text": "Powder: PubChem lists H302, H312 and H332 for the compound. Avoid swallowing it, skin contact and breathing the dust.",
        "source": "pubchem-tib2",
        "where": "Safety and Hazards, GHS Classification"
      },
      {
        "text": "Grade D is a greyish powder with at least 30.0 percent boron by mass, at most 1.1 percent oxygen and at most 0.1 percent iron (Hoganas datasheet). Control dust when handling it.",
        "source": "hoganas-pd5123",
        "where": "Chemical Characteristics table and Description of Product"
      }
    ],
    "mitigations": []
  },
  "uses": [
    {
      "application": "structures",
      "device": "Armour, cutting tools and wear-resistant parts",
      "example": "NIST lists TiB2 for impact-resistant armour, cutting tools, crucibles and wear-resistant coatings. The 2024 review lists high-temperature structural materials, cutting tools, armour, electrodes for metal smelting and wear-resistant parts.",
      "source": "nist-munro-2000",
      "where": "Section 1 (Introduction), first paragraph"
    },
    {
      "application": "mechanisms",
      "device": "Wear-resistant parts and coatings",
      "example": "The 2024 review names wear-resistant parts among TiB2 applications, and says TiB2 is a cathode material for salt-bath electrolysis in aluminium production.",
      "source": "lv-tib2-2024",
      "where": "Abstract and Introduction, first paragraph"
    }
  ],
  "supply": [
    {
      "subject": "Titanium (sponge metal, the titanium half of TiB2)",
      "abundance": "USGS: the United States produced no titanium sponge in 2025 and its last domestic plant closed in 2024. Imports of sponge were an estimated 44,000 tons in 2025.",
      "producers": [
        {
          "country": "China",
          "share_percent": 70.3,
          "year": 2025
        },
        {
          "country": "Japan",
          "share_percent": 14.3,
          "year": 2025
        },
        {
          "country": "Russia",
          "share_percent": 6.8,
          "year": 2025
        },
        {
          "country": "Kazakhstan",
          "share_percent": 4.3,
          "year": 2025
        },
        {
          "country": "Saudi Arabia",
          "share_percent": 3.2,
          "year": 2025
        }
      ],
      "critical_lists": [
        {
          "list": "EU critical raw materials list (Regulation (EU) 2024/1252, Titanium metal)",
          "listed": true
        }
      ],
      "recycling": "USGS: consumption data for titanium scrap are withheld. U.S. scrap imports were an estimated 32,000 tons in 2025. A Virginia company began making titanium powder from scrap in late 2024 and aimed for 1,400 tons per year in 2027.",
      "substitutes": [
        "USGS: aluminum, nickel, specialty steels and zirconium alloys may be substituted for titanium where corrosion resistance is needed (metal applications, not TiB2 specifically)."
      ],
      "source": "usgs-mcs2026-titanium",
      "where": "World Sponge Metal Production table, 2025 column (shares calculated by Space Mushroom: country sponge output over the 370,000 t world total as printed; the printed countries sum to 366,300 t); Domestic Production and Use; Events, Trends, and Issues; Recycling; Substitutes"
    },
    {
      "subject": "Boron (the boron half of TiB2)",
      "abundance": "USGS: borates occur in volcanic and arid deposits. The 2025 world production total is withheld (XX), so shares are not calculated. 2025 production as printed: Turkey 1,500, Bolivia 380, Chile 300, China 230 (boric oxide equivalent), Peru 220, Argentina 170, Russia 80, Germany 40. U.S. imports of all forms came from Turkey (90 percent, 2021 to 2024).",
      "producers": [],
      "critical_lists": [
        {
          "list": "USGS 2025 List of Critical Minerals (boron added in the final 2025 list, per the boron chapter)",
          "listed": true
        },
        {
          "list": "EU critical raw materials list (Boron/Borate)",
          "listed": true
        }
      ],
      "recycling": "USGS: insignificant.",
      "substitutes": [
        "USGS: substitution is possible in detergents, enamels, insulation and soaps. No substitute for boron in TiB2 is discussed."
      ],
      "source": "usgs-mcs2026-boron",
      "where": "World Production and Reserves table, 2025 column (world total XX); Import Sources (2021 to 2024); Critical lists paragraph in Events, Trends and Issues; Recycling; Substitutes"
    }
  ],
  "media": [],
  "documents": [
    {
      "title": "NIST J. Res. 105(5), Munro, Material Properties of Titanium Diboride (2000)",
      "type": "paper",
      "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
      "year": 2000
    },
    {
      "title": "Lv et al. 2024, Review on the Development of Titanium Diboride Ceramics, Recent Progress in Materials 6(2) (open access)",
      "type": "paper",
      "url": "https://lidsen.com/journals/rpm/rpm-06-02-009",
      "year": 2024
    },
    {
      "title": "USGS Mineral Commodity Summaries 2026, Titanium and Titanium Dioxide",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-titanium.pdf",
      "year": 2026
    },
    {
      "title": "USGS Mineral Commodity Summaries 2026, Boron",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-boron.pdf",
      "year": 2026
    },
    {
      "title": "PubChem compound record CID 92028754, Titanium diboride (GHS classification)",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/92028754",
      "year": 2026
    },
    {
      "title": "Hoganas datasheet PD-5123, Titanium Diboride Grades D, SE and F",
      "type": "datasheet",
      "url": "https://www.hoganas.com/globalassets/downloads/stc/PD-5123.pdf",
      "year": 2007
    },
    {
      "title": "Ozkan, Dokumaci and Onay 2017, Cyclic oxidation behavior of TiB2 pellets at elevated temperatures (abstract read)",
      "type": "paper",
      "url": "https://aperta.ulakbim.gov.tr/records/111472",
      "year": 2017
    },
    {
      "title": "Bahr et al. 2023, Quaternary diborides, Materials Research Letters 11(9) (TU Wien repository copy)",
      "type": "paper",
      "url": "https://doi.org/10.1080/21663831.2023.2225554",
      "year": 2023
    }
  ],
  "gaps": [
    "Titanium on the USGS 2025 List of Critical Minerals: the USGS list page returned HTTP 403 and the titanium chapter read does not state its status. Only the EU list is recorded.",
    "Boron producer shares are not calculated: the 2025 world total is withheld (XX) in the USGS boron chapter. Country tonnages are in the abundance text only.",
    "Titanium sponge shares are calculated against the 370,000 t world total as printed; the printed country values sum to 366,300 t.",
    "Molten aluminium and cathode corrosion of TiB2: no source read. The cathode use is described, but no corrosion or life data were found.",
    "Space use: no NASA, ESA or flight source for TiB2 was found. The NASA search returned ZrB2 and HfB2 ultra-high-temperature ceramics for sharp leading edges, which are other grades and were not used.",
    "Vacuum, radiation, thermal-vacuum and atomic-oxygen behaviour of TiB2: not read.",
    "Oxidation rates for bulk TiB2 in air: not found in a source read. Ozkan et al. is read as an abstract only; Bahr et al. covers thin films.",
    "Manufacturer datasheet with density, thermal conductivity and resistivity: the 3M TiB2 powder datasheet link returned an error page, and the Goodfellow and Cersol listings are distributor pages, so they were not used.",
    "Molar mass 69.489 g/mol and the hexagonal lattice constants (a 302.36 pm, c 322.04 pm) are on Wikipedia; they are not used as profile values, and the recipe uses only the NIST and Hoganas composition.",
    "Sources disagree on flexural strength (400 MPa NIST against 700 to 1000 MPa review), fracture toughness (6.2 against 4 to 5 MPa·m1/2), hardness at 20 degC (25 GPa NIST, Vickers 5 N, against 25 to 35 GPa review) and thermal conductivity (96 W/m·K NIST against 60 to 120 review). All are kept, with the source named.",
    "Designations (UNS, EN, DIN, JIS, AISI and similar codes) for TiB2: none printed in a source read in this run.",
    "Custom property names used because they are not in spores/property-canon.yaml: hardness, fracture_toughness, weibull_modulus, oxidation_resistance_temp, particle_size_d50.",
    "Compare paragraph: the review's comparison table has no readable column headings after text extraction, so the materials it compares TiB2 with are not named in this profile."
  ],
  "story": {
    "why": "Titanium diboride is a hard, stiff ceramic that also conducts electricity. At 20 degC NIST gives an elastic modulus of 565 GPa and a Vickers hardness of about 25 GPa for dense material. The review gives a melting point of 3225 degC. Those properties explain its use in armour, cutting tools and wear parts. Its oxidation resistance and sinterability are the main limits, which the review and the oxidation papers describe.",
    "uses": [
      {
        "where": "Armour, cutting tools and wear parts",
        "line": "NIST lists impact-resistant armour, cutting tools, crucibles and wear-resistant coatings. The 2024 review lists the same uses, plus high-temperature structural materials and electrodes for metal smelting."
      },
      {
        "where": "Aluminium production cathodes",
        "line": "NIST describes TiB2 cathodes for the electrochemical reduction of alumina to aluminium. The review calls it a cathode material for salt-bath electrolysis in aluminium production."
      },
      {
        "where": "Space applications",
        "line": "No flight, space or lunar source for TiB2 was read in this run."
      }
    ],
    "can_do": [
      {
        "label": "Stiffness",
        "line": "Dense TiB2 has an elastic modulus of 565 GPa at 20 degC (NIST trend value, about 5 percent uncertainty). The review gives 500 to 560 GPa.",
        "benchmark": "elastic_modulus",
        "scope": "material"
      },
      {
        "label": "Hardness",
        "line": "Vickers hardness is about 25 GPa at 20 degC at a 5 N load (NIST). It falls to 11 GPa at 500 degC and 4.6 GPa at 1000 degC. The review gives 25 to 35 GPa.",
        "benchmark": "hardness",
        "scope": "material"
      },
      {
        "label": "Melting",
        "line": "The review gives a melting point of 3225 degC for TiB2.",
        "benchmark": "melting_point",
        "scope": "material",
        "value": "3225 degC"
      },
      {
        "label": "Heat conduction",
        "line": "NIST gives 96 W/m·K at 20 degC, falling to 78.1 W/m·K at 1000 degC. The review gives 60 to 120 W/m·K.",
        "benchmark": "thermal_conductivity",
        "scope": "material",
        "value": "96 W/m·K"
      }
    ],
    "compare": "The review's property table sets TiB2 beside other high-temperature ceramics, but its column headings did not survive text extraction, so the materials it compares TiB2 with are not named here. Within this profile, TiB2 has a density of 4.5 g/cm3, a hardness of 25 to 35 GPa and a melting point of 3225 degC, with an oxidation resistance limit below 1200 degC.",
    "compare_rows": [
      {
        "label": "Density",
        "benchmark": "density",
        "scope": "material"
      },
      {
        "label": "Hardness",
        "benchmark": "hardness",
        "scope": "material"
      },
      {
        "label": "Thermal conductivity",
        "benchmark": "thermal_conductivity",
        "scope": "material"
      }
    ],
    "handling": [
      "Powder: PubChem lists H302, H312 and H332 for the compound. Avoid swallowing it, skin contact and breathing the dust.",
      "Oxidation: in air the surface forms TiO2 and B2O3. B2O3 volatilises as the temperature rises (Ozkan 2017, 800 to 1200 degC).",
      "Strength after high-temperature oxidation is lower at room temperature (NIST)."
    ],
    "good_for": [
      "Hard, stiff parts. NIST gives a Vickers hardness of about 25 GPa and an elastic modulus of 565 GPa at 20 degC.",
      "Electrically conductive hard parts. The review gives an electrical resistivity of 9 to 15 micro-ohm·cm."
    ],
    "watch_out": [
      "Brittleness: flexural strength of 400 MPa and a Weibull modulus of 11 at 20 degC (NIST).",
      "Oxidation: the review gives an oxidation resistance below 1200 degC and calls it inadequate for wide use. Thin films lose oxidation resistance above 400 degC (Bahr 2023).",
      "The sources disagree on flexural strength (400 MPa NIST against 700 to 1000 MPa review) and on thermal conductivity (96 W/m·K against 60 to 120 W/m·K).",
      "No space, radiation or molten-aluminium corrosion data were read."
    ],
    "verdict": "Titanium diboride is a hard, stiff, electrically conductive ceramic with a melting point of 3225 degC. Its limits are oxidation in air at high temperature and brittleness. The sourced uses are terrestrial (armour, cutting tools, wear parts and cathodes), and no space application was found.",
    "recipe": {
      "line": "TiB2 has one titanium atom and two boron atoms per formula unit, in a hexagonal layered structure (space group P6/mmm, NIST). Hoganas sells the powder as grades D, SE and F; grade D has at least 30.0 percent boron by mass and at most 1.1 percent oxygen. The review says pure TiB2 sinters poorly: near-theoretical density needs pressureless sintering above 2000 degC or sintering additives at lower temperature.",
      "parts": [
        {
          "name": "Titanium",
          "symbol": "Ti",
          "role": "Metal atom in the hexagonal structure. Titanium and boron together give TiB2 its hardness and electrical conductivity."
        },
        {
          "name": "Boron",
          "symbol": "B",
          "role": "Forms boron layers within the crystal. Boron is also the element that oxidises to B2O3 in air, which affects the oxidation behaviour."
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "Aggregated company notifications give three harmful-category hazard statements for titanium diboride, but 6.4 percent of reports say it does not meet GHS criteria. Treat the powder as harmful and control dust.",
        "points": [
          {
            "label": "Dust",
            "line": "Grade D is a greyish powder with a D50 of 3.5 to 6 micrometres (Hoganas). Control dust. The datasheet has no hazard section."
          },
          {
            "label": "Ingestion and skin",
            "line": "PubChem's H302 (harmful if swallowed) and H312 (harmful in contact with skin) appear in 90.1 percent of the reports that gave hazard codes."
          }
        ],
        "level": 0,
        "verdict": "Harmful if swallowed, in skin contact or inhaled (PubChem)"
      },
      {
        "title": "If a part fails",
        "lead": "These numbers are NIST trend values for dense material at 20 degC.",
        "points": [
          {
            "label": "Brittleness",
            "line": "Flexural strength of 400 MPa, fracture toughness of 6.2 MPa·m1/2 and a Weibull modulus of 11. The strength of one part can differ from another."
          },
          {
            "label": "Oxidation",
            "line": "Specimens oxidised at high temperature are weaker at room temperature, according to NIST."
          }
        ]
      }
    ]
  },
  "updated": "2026-10-26",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 27,
    "unreachable": 2,
    "caveats": 4,
    "note": "Written in this run from NIST Munro 2000 (Table 1 trend values), the 2024 open-access review (Table 1), PubChem GHS, USGS 2026 titanium and boron chapters, the Hoganas datasheet and two oxidation papers. The USGS critical-list page and the 3M datasheet were not readable. verify-values: 27 of 27 values found in their cited sources."
  },
  "sources": {
    "nist-munro-2000": {
      "title": "Munro, R. G., Material Properties of Titanium Diboride, J. Res. Natl. Inst. Stand. Technol. 105, 709-720 (2000)",
      "url": "https://nvlpubs.nist.gov/nistpubs/jres/105/5/j55mun.pdf",
      "kind": "paper",
      "license": "public domain (NIST)"
    },
    "lv-tib2-2024": {
      "title": "Lv X, Yin Z, Yang Z, Chen J et al., Review on the Development of Titanium Diboride Ceramics, Recent Progress in Materials 6(2), doi 10.21926/rpm.2402009",
      "url": "https://lidsen.com/journals/rpm/rpm-06-02-009",
      "kind": "paper",
      "license": "open access, CC BY (per the journal)"
    },
    "usgs-mcs2026-titanium": {
      "title": "USGS Mineral Commodity Summaries 2026, Titanium and Titanium Dioxide",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-titanium.pdf",
      "kind": "report",
      "license": "US government work, public domain"
    },
    "usgs-mcs2026-boron": {
      "title": "USGS Mineral Commodity Summaries 2026, Boron",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-boron.pdf",
      "kind": "report",
      "license": "US government work, public domain"
    },
    "pubchem-tib2": {
      "title": "PubChem compound CID 92028754, Titanium diboride (GHS classification, aggregated notifications; CAS 12045-63-5)",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/92028754",
      "kind": "database",
      "license": "PubChem public database"
    },
    "hoganas-pd5123": {
      "title": "Hoganas, Titanium Diboride Grades D, SE and F, datasheet PD-5123 (issue 5-31.07.2007)",
      "url": "https://www.hoganas.com/globalassets/downloads/stc/PD-5123.pdf",
      "kind": "datasheet",
      "license": "vendor datasheet, cited not reproduced"
    },
    "ozkan-2017": {
      "title": "Ozkan I, Dokumaci E, Onay A. B., Cyclic oxidation behavior of TiB2 pellets at elevated temperatures (2017)",
      "url": "https://aperta.ulakbim.gov.tr/records/111472",
      "kind": "paper",
      "license": "repository record (abstract read)"
    },
    "bahr-2023": {
      "title": "Bahr A. et al., Quaternary diborides, improving the oxidation resistance of TiB2 coatings by disilicide alloying, Materials Research Letters 11(9), 733-741 (2023)",
      "url": "https://doi.org/10.1080/21663831.2023.2225554",
      "kind": "paper",
      "license": "author version in TU Wien repository"
    },
    "ec-crm": {
      "title": "European Commission, Critical raw materials (list under Regulation (EU) 2024/1252)",
      "url": "https://single-market-economy.ec.europa.eu/sectors/raw-materials/areas-specific-interest/critical-raw-materials_en",
      "kind": "web",
      "license": "European Commission web page"
    },
    "wikipedia-tib2": {
      "title": "Wikipedia, Titanium diboride (molar mass, structure and history only)",
      "url": "https://en.wikipedia.org/wiki/Titanium_diboride",
      "kind": "web",
      "license": "CC BY-SA"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/titanium-diboride/"
}