CERAMIC BALL, BALL BEARING, MOTOR WITH BEARING, HARD DISK DEVICE, POLYGON SCANNER AND MANUFACTURING METHOD OF CERAMIC BALL

摘要

PROBLEM TO BE SOLVED: To provide a method of manufacturing a ceramic ball having few voids and a uniform density distribution. SOLUTION: A preformed material in the shape of a ball is held in a rubber mold and a spheric formed material is obtained by applying pressure to the preformed material inside the rubber mold through the intermediary of the mold. In this process, the rubber hardness of the mold is made 65 or less. Thereby it is possible to form the formed material having a high density and a substantially uniform density distribution and to manufacture the ceramic ball having few voids and a substantially uniform strength distribution.