Abstract: The structure and properties of GCr4 bearing steel- 1.00%C,0.40%Cr,0.03%Mo,0.034%Al,10 × 10^-6[O] heat treated by cross section induction heating and quenching (840±10)℃ + tempering (150～160 ℃) have been tested and researched. Results showed that after heat treated the case structure of CCr4 steel consisted of twinned martensite and dislocation martensite,and the core structure was troostite + sorbite. The hardenability of GCr4 steel(J60, 3.0 mm)was markedly lower than that of GCr15 bearing steel- 1.01%C,1.52%Cr,11×10^-6[O] ( J60,4.5 mm),the impact toughness and fracture toughness Kc of GCr4 steel increased respectively by 66%～104% and 67% as compared with that of steel GCr15 heat treated by(840±10)℃ quenching +(150~160)℃ tempering , and the contact fatigue life of steel GCr4 increased by 12%～26% as compared with that of steel CCr15.

Key words: Restricted Hardenability GCr4 Bearing Steel, Structure, Impact Toughness, Fracture Toughness, Contact Fatigue Life

摘要： 试验研究了成分为:1.00%C、0.40%Cr、0.03%Mo、0.034%Al、10×10^-6[O]的GCr4轴承钢经感应穿透加热-表面淬火(840±10)℃+回火150～160℃后的组织和性能。结果表明,热处理后GCr4钢表面层由孪晶马氏体和位错马氏体组成,心部组织为屈氏体+索氏体。GCr4钢的淬透性(J60,3.0 mm)明显低于GCr15钢(1.01%C、1.52%Cr、11×10^-6[O])的淬透性(J60,4.5 mm);其感应加热淬火+回火的冲击韧性和断裂韧性KIC分别比(840±10)℃淬火+(150～160)℃回火的GCr15钢提高66%～104%和67%。GCr4钢接触疲劳寿命较GCr15钢提高12%～26%。

关键词: GCr4限制淬透性轴承钢, 组织, 冲击韧性, 断裂韧性, 接触疲劳寿命