Full ceramic bearing made with Si3N4 have some better performance than ZrO2, the rings and balls made by full ceramic material:Si3N4, as a standard constructure,the cage made by PTFE, generally we also could make the cage with GFRPA66-25,PEEK,PI, Phonemic Textiles Tube ,etc. Compares than the material of ZrO2 ,The SiN4 ceramics bearings could endure heavier load and could be used in higher temperature environment. Also we could offer precision ceramic bearing which generally used in high-speed and high-rigidity spindle.the manufactured clearance could be P4 TO UP grade. 

Out ring :Si3N4(or ZRO2)
Inner ring :Si3N4(or ZRO2)
Ball       :  Si3N4(or ZRO2)
Cage:        PTFE