ZIRCONIUM OXIDE SINTERED COMPACT AND BALL BEARING AND BEARING MEMBER USING THE SAME

摘要

PROBLEM TO BE SOLVED: To improve the trouble due to static electricity and high-speed rotating properties by using bearing balls using a zirconium oxide sintered compact having a specified number of materials for imparting electroconductivity in 50 μm linear distance in electronic equipment such as a hard disk drive. SOLUTION: A zirconium oxide sintered compact prepared by including, e.g. particles of carbides of groups 4a, 5a, 6a and 7a elements used as the materials for imparting the electroconductivity so that 3-20 particles are present in 50 μm linear distance is applied to bearing balls. In the process, the zirconium oxide sintered compact is devised so that the maximum diameter of the materials for imparting the electroconductivity does not exceed 10 μm and the high-speed rotating properties are thereby improved.