The contact fatigue strength of the bearing is related to the wear resistance of the bearing, the hardness of the bearing steel, the rust resistance of the bearing steel, and the processing performance.

First, the cracking and spalling of the bearing is caused by the cyclic load of the bearing, and the contact surface is prone to fatigue damage. Therefore, in order to improve the service life of the bearing, the bearing steel must have high contact fatigue. strength.

Second, wear resistance

The wear resistance of bearing steel is good and bad, which directly affects the sliding friction between the ferrule, the rolling element and the cage when the bearing is working, so that the bearing parts Constant wear and tear In order to reduce the wear of parts during bearing work, maintain bearing accuracy and stability, and extend service life, better bearing steel must be used as the material.

III. Hardness

Hardness is one of the important qualities of bearing quality and has a direct impact on contact fatigue strength, wear resistance and elastic limit. The hardness of the bearing steel in the use state generally reaches HRC61~65, in order to obtain high contact fatigue strength and wear resistance of the bearing.

IV. Anti-rust performance

In order to prevent corrosion and rust of bearing parts and finished products during processing, storage and use, bearing steels are required to have good anti-rust properties.

V. Processing performance

Bearing parts are subjected to many cold and hot processing steps in the production process. In order to meet the requirements of high volume, high efficiency and high quality, bearing steel Should have good processing properties. For example, cold, thermoforming properties, machinability, hardenability, and the like.

Common materials for bearing parts are: high carbon chromium bearing steel, carburized steel (such as 20Cr2Ni4A, 15Mn, 20Cr2MnMoA), high temperature bearing steel (such as Cr4Mo4V, Cr14Mo4, Cr15Mo4V, W18Cr4V), stainless bearing steel (9Cr18, 9Cr18Mo, 1Cr18Ni9Ti), vacuum degassing steel, anti-magnetic bearing steel, etc., the most commonly used is high carbon chromium bearing steel. The basic steel grades of high carbon chromium bearing steels are GCr6, GCr9, GCr9SiMn, GCr15, GCr15SiMn. It is the most widely used and most used steel in the bearing manufacturing industry in China. It has good wear resistance and contact fatigue performance. Ideal processing performance with a certain degree of flexibility and toughness.

In addition to the above basic requirements, bearing steels should also meet the requirements of proper chemical composition, uniform internal organization, less non-metallic inclusions, internal surface defects meeting the standard and surface decarburization layer not exceeding the specified concentration. The project has clear regulations in the raw material standards.