抄録
Mechanical properities such as fracture toughness and bending strength were determined in zirconia-3 mol% yttria (PSZ) containing 0-5mass% alumina addition. They were sintered at various temperatures ranging 1673-1873K and various times ranging 1-8h. The mechanical properties of PSZ were improved by a small addition of alumina. This improvement is not related to the factors of density and grain size, but will be related to the formation of grain boundary phase, which is consisted of amorphous structure enriched alumina, silica, yttria and magnesia. The sintering of PSZ containing alumina occurs by liquid sintering mechanism.