G20Cr2Ni4A钢渗碳轴承滚子断裂失效分析

Fracture failure analysis of G20Cr2Ni4A steel bearing roller

经表面先渗碳再淬火、回火处理后的G20Cr2Ni4A钢轴承滚子在试车约2 h后断裂。采用金相显微镜、维氏硬度计、扫描电镜、X荧光光谱仪等检测手段对该轴承滚子的开裂原因进行了分析。结果表明,该轴承滚子显微组织、化学成分、硬度及渗碳层厚度等均合格;轴承装配时,工作辊轴线与支承辊轴线不平行造成轧机在运行时轴向力过大,导致轴承滚子开裂失效。

The G20Cr2Ni4A steel bearing roller, quenched and tempered after carburizing , fractured after test running about 2 hours.The fracture of G20Cr2Ni4A steel bearing roller was analyzed by metallurgical microscope , Vickers hardness tester, scanning electron microscope and X ray fluorescence spectrometer etc .The results show that the microstructure , hardness, carburized layer depth and chemical composition are all qualified .The primary reason of the fracturing is the overloaded axial force caused by that the working roll shaft line is not parallel to the supporting roller line when installed .