大型高碳铬轴承钢环件探伤不合格成因与控制  

Cause and Control on Unqualified UT of Large-size High-carbon High-chromium Bearing Steel Ring

作　　者：李涛[1] 马永强[1] 蔡青[1] 马俊杰[1] 

机构地区：[1]抚顺特殊钢股份有限公司技术中心,辽宁抚顺113001

出　　处：《热加工工艺》2013年第11期230-231,239,共3页Hot Working Technology

摘　　要：采用金相显微镜、扫描电镜分析了大规格高碳铬轴承钢环件中间坯合格而辗制出的成品环件出现点状偏析超声波探伤不合格的原因。试验结果表明:缺陷为内部裂纹,裂纹源于浇注过程中轴承钢内部形成的(Cr,Fe)C化合物的枝晶偏析,属液析碳化物,其根本原因为辗环前加热温度偏高,扩散退火不充分。通过调整辗环前加热温度不仅解决了探伤缺陷问题,并且碳化物网状也有所改善。The reason why the large-size high-carbon high-chromium bearing steel ring products produced spot segregation was analyzed by using the optical microscope and scanning electron microscope. But their intermediate billet had passed the ultrasonic inspection. Test results show that the defects are internal cracks, which come from the dendritic segregation of （Cr,Fe）C formed during casting. The main cause for this defect is that the high heating temperature and annealing time of insufficient diffusing before ring rolling. Through adjusting heating temperature before ring rolling, the defect found by the ultrasonic inspection is solved, and the carbide mesh is also improved.

关 键 词：轴承钢 环件 液析 碳化物 裂纹 

分 类 号：TG142.7[一般工业技术—材料科学与工程]