Patent ID: 11845697

Abstract:
The composite sintered body includes Al2O3, and MgAl2O4. The content of Al2O3 in the composite sintered body is not less than 95.5% by weight. The average sintered grain size of Al2O3 in the composite sintered body is not less than 2 μm and not greater than 4 μm. The standard deviation of sintered grain size distribution of Al2O3 in the composite sintered body is not greater than 0.35. The bulk density of the composite sintered body is not less than 3.94 g/cm3 and not greater than 3.98 g/cm3. In the composite sintered body, the ratio of amount of crystal phase of MgAl2O4 to that of Al2O3 is not less than 0.003 and not greater than 0.01.