With the development of high-speed machining technology, high-speed and high-precision machine tools have also become one of the main development trends. The key component of high-speed machine tools is the high-speed electric spindle. The bearing supporting the electric spindle causes the contact points between the rings and the rolling elements to be subjected to external loads and rotation due to the rotation of the spindle.Traditional steel bearings are not suitable for high-speed machine tools because of their material properties, resulting in large centrifugal forces during operation and short fatigue life.

Silicon nitride ceramic bearings (Si3N4) have the advantages of low density, medium elastic modulus, small thermal expansion coefficient, high hardness, high temperature resistance, corrosion resistance, etc., which can improve the contact fatigue life of bearings. In particular, high-speed ceramic bearings can be used at high speeds of 12000~75000r/min, suitable for high-speed machine tool spindles and other high-precision equipment.