摘要
某机组的1Cr9Mo VNb N钢阀座在堆焊司太立合金处产生裂纹,通过断口特征分析、材质理化检验、硬度梯度测试、受力分析等对阀座裂纹产生原因进行分析。最终得出结论:阀座堆焊后在阀座基材与司太立合接合处形成高硬度的硬化层,从而使阀座承受冲击载荷时产生裂纹而失效。
1Cr9MoVNbN valve seat of a plant unit cracked in the built- up welding stellite place.Through the analysis of the characteristics of fracture,material physical and chemical inspection,hardness gradient test and force analysis,the results show that hardened layer of high hardness was formed at the joint between the valve seat base material and stellite,so this resulted in the seat lose efficiency under impact load.
关键词
阀座
司太立合金
硬化层
Valve seat
stellite
hardened layer
