1988 年 37 巻 412 号 p. 70-76
Si3N4 power with sintering additives was compacted on a three-dimensional compaction device and the characteristics of this powder during compaction were investigated. It appeared that, to obtain a compact having the same density ratio, much lower pressure was required compared with the same powder without sintering additives. Material constants in the constitutive equations for the powders were determined from the experiments. These equations were then applied to the analysis of isostatic compaction by using the rigid-plastic finite element method. The shape of compacts and the distributions of density ratio and stress were calculated. They show that the difference in material constants used in constitutive equations affects the calculated results considerably.