Bearing steel is mainly used in the manufacture of rolling bearings of rolling body and ring. Due to bearing should have long life, high precision, low calorific value, recommend suite, high rigidity, low noise, high abrasion resistance and so on characteristics, therefore requires bearing steel should have: high hardness, uniform hardness, high elastic limit, high contact fatigue strength, must be certain hardenability and tenacity, in the atmospheric corrosion resistance of lubricant. In order to achieve the performance requirements, the uniformity of the chemical composition of bearing steel, non-metallic inclusion content and type, strict carbide particle size and distribution, decarburization, etc. Bearing steel in general to develop in the direction of high quality, high performance and many varieties. According to the characteristics and application environment of bearing steel is divided into: high carbon chromium bearing steel, carburized bearing steel, high temperature shaft