1、 Contact fatigue strength

Under the action of cyclic loads, the contact surface of bearings is prone to fatigue damage, namely cracking and peeling, which is the main form of bearing damage. Therefore, in order to improve the service life of bearings, bearing steel must have high contact fatigue strength.

2、 Wear resistance performance

When the bearing is working, not only rolling friction but also sliding friction occurs between the ring, rolling elements, and cage, resulting in continuous wear of the bearing parts. In order to reduce the wear of bearing parts, maintain the stability of bearing accuracy, and extend the service life, bearing steel should have good wear resistance.

3、 Hardness

Hardness is one of the important qualities of bearing quality, which has a direct impact on contact fatigue strength, wear resistance, and elastic limit. The hardness of bearing steel in use generally needs to reachHRC61~65Only then can the bearing achieve high contact fatigue strength and wear resistance.

4、 Rust prevention performance

In order to prevent corrosion and rust of bearing parts and finished products during processing, storage, and use, it is required that bearing steel should have good anti rust performance.

5、 Processing performance

During the production process of bearing parts, many cold and hot processing steps are required. In order to meet the requirements of large quantities, high efficiency, and high quality, bearing steel should have good processing performance. For example, cold and hot forming performance, cutting performance, hardenability, etc.

In addition to the basic requirements mentioned above, bearing steel should also meet the requirements of appropriate chemical composition, uniform internal structure, minimal non-metallic inclusions, internal surface defects meeting standards, and surface decarburization layer not exceeding the specified concentration. These items are clearly specified in the raw material standards.

The commonly used materials for bearing parts include high carbon chromium bearing steel and carburizing steel (such as20Cr2Ni4A、15Mn、20Cr2MnMoA）High temperature bearing steel(asCr4Mo4V、Cr14Mo4、Cr15Mo4V、W18Cr4V)Stainless bearing steel(9Cr18、  9Cr18Mo、1Cr18Ni9Ti)Vacuum degassing steel, anti magnetic bearing steel, etc., among which the most commonly used is high carbon chromium bearing steel. The basic steel grades for high carbon chromium bearing steel areGCr6 、GCr9、GCr9SiMn、GCr15、GCr15SiMnIt is the most widely used and widely used steel grade in China's bearing manufacturing industry, with good wear resistance and contact fatigue performance, ideal processing performance, and certain elasticity and toughness.