During energy conversion of Dalian motor housing, a small part of the loss is always converted into heat, which must be continuously dissipated through the motor housing and surrounding media. This process of heat dissipation is called cooling. At present, ceramic bearings are widely used in the market. Generally, the inner and outer rings of angular contact ceramic bearings are steel rings, and the rolling elements are ceramic materials. Ceramics have the advantages of low density, good stiffness and low coefficient of thermal expansion. Moreover, the theoretical calculation, contact fatigue test and crushing test show that the steel ring rather than the ceramic ball is the first failure of the hybrid ceramic bearing. Moreover, the theoretical calculation, contact fatigue test and crushing test show that the steel ring rather than the ceramic ball is the first failure of the hybrid ceramic bearing. Because the theoretical life of the first three kinds of bearings is infinite, especially the magnetic bearings have the advantages of automatic adjustment of eccentricity. In the future ultra-high speed machine tool market, with the development of technology, magnetic bearings should be the development direction. In general high-speed machining machine tools, hybrid ceramic bearings or pure ceramic bearings will also have a wide range of applications.