| 摘要 |
PURPOSE:To obtain the alumina-silica-based ceramic sintered body having higher strength at high temp. than at ordinary temp. and having the high absolute value of strength by excluding the inhomogeneity of raw powder and limiting the amt. of an alkali metal oxide. CONSTITUTION:An aluminum alkoxide and a silicon alkoxide shown by the general formula SinOn-1(OR)2n+2 (n>=1 and R is an alkoxy group) are dissolved in a solvent, and the obtained nonaqueous mixed soln. is hydrolyzed with the distilled water controlled to pH11 with ammonia. Consequently, a raw powder with the weight ratio of Al2O3 to Al2O3 plus SiO2 controlled to 62-73% and contg. <=1000ppm of the Na2O plus K2O as the impurities is synthesized. The raw powder is calcined at 950-1200 deg.C, the calcined body is crushed, and the crushed material is formed and then sintered at 1500-1700 deg.C at atmospheric pressure. A sintered body having >=300Mpa ordinary-temp. strength and >=400MPa high-temp. (1300 deg.C) strength is obtained in this way. |
