| 摘要 |
PURPOSE:To enhance fluidity, shape retaining properties, strength, white transparency and smoothness by injection-molding the kneaded material of specified zirconia powder and an organic binder and thereafter degreasing and sintering the molded body. CONSTITUTION:Zirconia composition for injection molding is obtained by dissolving 2-10mol% yttria to prepare a solid solution and kneading both 100 pts.wt. zirconia powder having <=12m<2>/g BET specific surface area, 0.05-0.5mum mean particle diameter and <=3mum.m<2>/g product of the mean particle diameter and the BET specific surface area and 5-30 pts.wt. organic binder (e.g. paraffin) at 90-180 deg.C for 30 minutes to 5 hours while using a pressure-kneader. Then this composition is injection-molded under the conditions of 100-2000kg/cm<2> injection pressure, 0.1-10cm/sec injection velocity, 10-70 deg.C temp. of a mold and 100-180 deg.C temp. of a cylinder. Thereafter the molded body is heated to 500 deg.C at a temp. rise rate of (5-150) deg.C/hour and held for 5-100 hours and degreased. Then it is sintered at 1300-1600 deg.C for 0.2-10 hours to give a sintered body. |
