| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve a problem that it is difficult to attain both characteristics of excellent transparency and excellent mechanical strength in a zirconia sintered body. <P>SOLUTION: A zirconia sintered body which has excellent light transmission properties, namely a linear transmittance of not less than 50% for a 1 mm-thick sample at a visible light wavelength for measurement of 600 nm and high strength, namely an average bending strength of not less than 300 MPa, is obtained by subjecting a primary zirconia sintered body that has an average crystal grain size of not more than 1 μm and relative density of not less than 92% and is composed only of cubic crystal phases to a HIP treatment at ≥1,250°C and ≤1,600°C at not less than 50 MPa. The primary sintered body is obtained by maintaining a zirconia powder compact that contains ≥7 mol% and ≤30 mol% of yttria at ≥1,100°C and ≤1300°C for not less than 5 hours, or by quickly heating the zirconia powder compact at a rate of not less than 500°C/hour. <P>COPYRIGHT: (C)2011,JPO&INPIT |
