| 摘要 |
PURPOSE:To obtain the subject parts having excellent impact resistance and reliability at a high yield by presintering an Si3N4 molding contg. Y2O3, CeO2 and ZrO2 as a sintering assistant in an inert gaseous atmosphere of a prescribed temp., then changing temp. conditions and subjecting the molding to a hot isostatic treatment which acts commonly as regular sintering. CONSTITUTION:The molding obtd. by adding 2-30wt.% sintering assistant contg. 30-70wt.% ZrO2 and >=1wt.% Y2O3 and CeO2 to the Si3N4 powder then mixing and molding the mixture is first presintered in the inert gaseous atmosphere kept at 1,370-1,600 deg.C. This molding is then subjected to the hot isostatic treatment which acts commonly as normal sintering in the inert gaseous atmosphere kept at <=1,750 deg.C. |
