... 2) The rings and balls made of full ceramic material: ZrO2, SisN4 and Sic as a standardstructure, the cage ... , single direction thrust ceramic ball bearings and angularcontact ceramic bearings4) Ceramic balls: all kinds of ceramic balls with the precision ... from G5 to G200,made of the material ZrO2, SiN4, SiC and Al2O3 ...