The reasons why silicon nitride bearings are needed in new energy vehicles are as follows:

1，Electric motor bearings require materials with lower density and relatively higher wear resistance compared to traditional bearings.2，Due to the changes in the surrounding electromagnetic field caused by the alternating current of the motor, better insulation is needed to reduce the electrical corrosion caused by bearing discharge.3，The requirement is for the bearing ball surface to be smoother and have less wear. Ceramic balls have characteristics such as low density, high strength, and friction resistance, making them suitable for high-speed rotation conditions. In the high-temperature, strong magnetic, and high vacuum field, silicon nitride ceramic balls are irreplaceable. 

Preparation key points of silicon nitride ceramic balls.

Preparation of ultra-precision silicon nitride ceramic balls is a prerequisite for manufacturing high-end silicon nitride ball bearings. High-end silicon nitride ceramic balls typically need to simultaneously achieve three key technical indicators: high precision, long fatigue life, and good surface quality.