PRODUCTION OF SPHERICAL CERAMIC SINTERED COMPACT, AND SPHERICAL CERAMIC SINTERED COMPACT

摘要

PROBLEM TO BE SOLVED: To obtain a spherical ceramic sintered compact having reduced defects and producible in a high efficiency and to provide a method for producing the sintered compact. ;SOLUTION: Ground powder for molding is spherically attached and stuck to the circumference of a molding nucleus body 50 while the molding nucleus body 50 is being rolled on a ground powder layer 10k for molding in a rotating granulation container to give a spherical molding body 80. Consequently the density of a stuck layer 10a of the molding ground powder growing around the molding body 80 can be extremely raised and the formed stuck layer 10a has reduced defects such as pore and cracks caused by bridging of powder particles. The spherical molding body 80 is baked. Consequently, the obtained spherical ceramic sintered compact comprises a nucleus part derived from the molding nucleus body 50 at the central part of the sintered compact distinguishable between it and an outer layer part derived from the stuck layer 10a having high density and a few defects when a section passing through approximately the central part of the sintered compact is polished, enlarged and observed. The polished surface is made into a sintered compact structure showing the texture to give the objective spherical ceramic sintered compact having a small ratio of defect formation on the surface part, a high density and a high strength.;COPYRIGHT: (C)2000,JPO