| 摘要 |
PURPOSE:To obtain high precision and high strength spinel ceramics by adding one or more among oxides of rare earth elements and multiple oxides each of a rare earth element and other metallic element to spinel powder, mixing and firing them and carrying out densification. CONSTITUTION:Spinel (MgAl2O4) having 10m<2>/g specific surface area and 99.9% purity is used as a base and one or more among oxides of rare earth elements, e.g. Y2O3 and multiple oxides each of a rare earth element and other metallic element, e.g. Y3Al5O12 are added to the base by 0.1-30wt.%. They are mixed and subjected to pressureless sintering or hot, pressing at 1,400-1,600 deg.C in the air or in gaseous O2, N2 or Ar. The resulting ceramics has >=95% theoretical density ratio and >=20kgf/mm<2> bending strength. |
