{
  "name": "Alumina ceramic properties by purity: 96% and 99.5% (named suppliers' typical values)",
  "description": "Density (g/cm³ and kg/m³), thermal conductivity, thermal expansion, specific heat, Knoop hardness, flexural strength and dielectric strength for two dense alumina grades: CoorsTek AD-96 (96%) and CoorsTek AD-995 (99.5%), with each supplier's test conditions. Typical values for those suppliers' named materials, as published by them.",
  "license": "https://creativecommons.org/licenses/by/4.0/",
  "credit": "Source: GY Alumina (gyalumina.com), CC BY 4.0",
  "creator": "GY Alumina",
  "url": "https://gyalumina.com/resources#data-alumina-properties",
  "guide": "https://gyalumina.com/guides/alumina-density-properties-by-purity",
  "dateModified": "2026-10-16",
  "columns": [
    {
      "key": "supplier",
      "description": "Whose figures these are"
    },
    {
      "key": "grade",
      "description": "Supplier's grade name"
    },
    {
      "key": "al2o3_purity",
      "description": "Al₂O₃ content as the supplier states it"
    },
    {
      "key": "density_g_cm3",
      "description": "Density, g/cm³"
    },
    {
      "key": "density_kg_m3",
      "description": "Density, kg/m³"
    },
    {
      "key": "thermal_conductivity_w_mk",
      "description": "Thermal conductivity, W/m·K, with the temperature"
    },
    {
      "key": "thermal_expansion_1e-6_per_k",
      "description": "Thermal expansion, 10⁻⁶/K (CoorsTek: 25–1,000 °C)"
    },
    {
      "key": "specific_heat_j_kgk",
      "description": "Specific heat, J/kg·K (CoorsTek: at 100 °C)"
    },
    {
      "key": "knoop_hardness_gpa",
      "description": "Knoop hardness, GPa (CoorsTek: at 1 kgf)"
    },
    {
      "key": "flexural_strength_mpa",
      "description": "Flexural strength, MPa"
    },
    {
      "key": "flexural_strength_test",
      "description": "Strength test conditions as the supplier states them"
    },
    {
      "key": "dielectric_strength_kv_mm",
      "description": "Dielectric strength, ac kV/mm (CoorsTek: on 6.35 mm thick samples)"
    },
    {
      "key": "source_url",
      "description": "The supplier's property page"
    }
  ],
  "rows": [
    {
      "supplier": "CoorsTek",
      "grade": "AD-96",
      "al2o3_purity": "96% nominal",
      "density_g_cm3": "3.72",
      "density_kg_m3": "3,720",
      "thermal_conductivity_w_mk": "24.7 at 20 °C",
      "thermal_expansion_1e-6_per_k": "8.2",
      "specific_heat_j_kgk": "880",
      "knoop_hardness_gpa": "11.5",
      "flexural_strength_mpa": "343",
      "flexural_strength_test": "four-point, 20 °C",
      "dielectric_strength_kv_mm": "8.3",
      "source_url": "https://www.coorstek.com/en/materials/alumina/"
    },
    {
      "supplier": "CoorsTek",
      "grade": "AD-995",
      "al2o3_purity": "99.5% nominal",
      "density_g_cm3": "3.90",
      "density_kg_m3": "3,900",
      "thermal_conductivity_w_mk": "30.0 at 20 °C",
      "thermal_expansion_1e-6_per_k": "8.2",
      "specific_heat_j_kgk": "880",
      "knoop_hardness_gpa": "14.1",
      "flexural_strength_mpa": "300",
      "flexural_strength_test": "four-point, 20 °C",
      "dielectric_strength_kv_mm": "8.7",
      "source_url": "https://www.coorstek.com/en/materials/alumina/"
    }
  ]
}