中文摘要：

利用宏观形貌分析、显微组织分析和力学性能测试等方法,对某无缝钢管厂生产的高铬白口铸铁球形顶头的失效进行了分析。分析表明,球形顶头畸变和开裂失效主要是由其组织中存在较多的缩孔和微裂纹缺陷,共晶碳化物呈粗大网状分布,Cr、Si含量过高且存在一定的成分偏析,高温组织稳定性较差等原因引起。同时提出了相应的改进措施建议。

英文摘要：

Failure analysis of high chromium white cast iron spherical plug of plug pipe mill of a seamless steel pipe plant was performed by using macroscopic morphology observation,microstructure analysis and mechanical properties test.The results show that the main reasons for deformation and crack of spherical plug are as follows： the existence of numerous shrinkage cavities and micro-crack defects;the reticular distribution of bulky eutectic carbide;the segregation and excessive content of chromium and silicon and the poor high temperature structure stability are the major inducing factors of the deformation and crack of high chromium white cast iron spherical plugs.And then the corresponding improvement measures are put forward.