PROBLEM TO BE SOLVED: To provide a light-transmitting zirconia sintered compact excellent in resistance to hydrothermal degradation in addition to strength and toughness.SOLUTION: A light-transmitting zirconia sintered compact containing 2.5 to 3.5 mol% of yttria and 0.05 to 0.3 wt% of alumina and having a tetragonal rate of 90 wt% or more and a light transmissivity at 600 nm of wavelength of 30% or more with a sample thickness of 1.0 mm, is used. The sintered compact is produced by molding a zirconia powder containing 2.5 to 3.5 mol% of yttria and 0.05 to 0.3 wt% of alumina and having a BET (Brunauer, Emmet and Teller) equation specific surface area of 13 to 20 m2/g and an average particle diameter of 0.4 μm or less, and heating it at a temperature in a range of 800 to 1,100°C to obtain a calcined body, then firing the calcined body at a temperature in a range of 1,150 to 1,250°C by an electromagnetic heating.COPYRIGHT: (C)2014,JPO&INPIT【課題】 強度及び靭性に優れており、これに加えて耐水熱劣化性に優れる透光性ジルコニア焼結体を提供する。【解決手段】 イットリアを2.5~3.5モル%及びアルミナを0.05~0.3重量%含み、正方晶率が90重量%以上、かつ、試料厚み1.0mmでの波長600nmの光透過率が30%以上の透光性ジルコニア焼結体を用いる。該焼結体は、イットリアを2.5~3.5モル%及びアルミナを0.05~0.3重量%含み、BET比表面積13~20m2/g、平均粒径0.4μm以下のジルコニア粉末を成形し、800~1100℃で加熱して仮焼体を得、次いで、該仮焼体を電磁波加熱によって1150~1250℃で焼成して得る。【選択図】 なし
