| 摘要 |
PROBLEM TO BE SOLVED: To obtain a zirconia fine powder excellent in moldability and sinterability, and to provide a method for producing such zirconia fine powder. SOLUTION: The zirconia fine powder has the following characteristics: BET specific surface area is 13-19 m2/g, the average size of secondary agglomerated particle is <=1 μm, the strain coefficient of tetragonal phase determined by powder X-ray diffractometry is <=0.005, and the average size of primary particle measured by electron microscope is 0.04-0.07 μm, and the ratio: (the average size of primary particle measured by electron microscope/the average particle size determined from BET specific surface area) is 0.6-0.9. The other objective method for producing such zirconia fine powder comprises the following process: a mixed solution composed of a yttrium compound and a hydrated zirconia sol prepared at >=90% yield by hydrolysis of an aqueous solution of a zirconium salt and containing yttria at 2-4 mol% is evaporated to dryness, the resulting solid is preliminarily burned at 750-1,150 deg.C to form zirconia powder, which is then mixed with an aqueous solution into a zirconia slurry at a pH of 7 to 9 which, in turn, is put to wet pulverization. |
