回火温度对GCr15轴承钢组织和性能的影响

Effect of Tempering Temperature on Microstructure and Properties of GCr15 Bearing Steel

摘要: GCr15钢在轴承中广泛使用，其回火温度对轴承使用性能有重要影响。研究了不同回火温度对GCr15轴承钢的硬度、残余奥氏体含量、表面残余应力的影响。结果表明：当GCr15的回火温度为165~300℃时，随着回火温度的升高，硬度HRC由61.7降到56.2，残余奥氏体含量由9.88%下降到3.26%，表面残余应力由706.8 MPa下降至382.2 MPa；其显微组织主要为针状马氏体、颗粒碳化物和少量的亚稳定相残余奥氏体，随着回火温度的提高，碳化物逐渐聚集并不断长大。该研究为GCr15钢低温回火工艺的制定提供参考。

Abstract: GCr15 steel is widely used in bearing. The tempering temperature has a significant effect on its properties. The effect of different tempering temperature on hardness, residual austenite and surface residual stress of GCr15 steel was investigated. The result shows that with the increasing of tempering temperature in the range of 165~300℃, the hardness HRC of the tested steel decreased from 61.7 to 56.2 , the residual austenite from 9.88% to 3.26% and the surface residual stress from 706.8 MPa to 382.2 MPa, accompanied with the gathering and growth of carbide. The microstructure is mainly composed of needle-type martensite, grain-type carbide and little residual austenite. This study provides reference for establishing low-temperature tempering process for GCr15 steel.