Si3N4 Ceramic ball with good ability of isolation and no magnetism is the precision ceramic that fired in high temperature without oxidation air,which has the high intension, high wearing resistance, high temperature resistance,anti-canker,strong acid and alkali resistance,can be used in seawater for a long time. At **0, the intension and rigidity almost couldn't be changed, whose density is 3.*0g/cm3 and is the 1/3 of the weight of bearing steel. There are small centrifugal force when circumgyrating and  run at high speed.It also has the self-lubrication, and can be used in the environment with no lubricate medium and high pollutaion.which is the best material of Hybrid construction ceramic ball bearing.