Since turbochargers often work at high temperatures and high speed，the temperature of the waste turbine end of the supercharger is about 600 ℃. Turbocharger rotor rotates at 8000-11000r/min high speed. Therefore, in order to ensure the normal operation of the supercharger, the mechanical properties of the bearing play a decisive role. The high purity steel is used for turbocharger bearings, which increases the life of bearings by 75%.Geman used lubricating grease and lubricating technology can improve the bearing performance. We select high quality silicon nitride ceramic ball to ensure the ideal height of bearing configuration. The bearing raceway is honed to minimize the noise and improve the mechanical properties of the bearing.