无缝钢管表面异常磁痕产生原因  

Causes of abnormal magnetic marks on seamless steel pipe surface

作　　者：杜志杰 张凯 DU Zhijie;ZHANG Kai(Xi’an Moore Petroleum Engineering Laboratory Co.,Ltd.,Xi’an 710065,China)

机构地区：[1]西安摩尔石油工程实验室股份有限公司,西安710065

出　　处：《理化检验（物理分册）》2024年第6期71-74,共4页Physical Testing and Chemical Analysis(Part A:Physical Testing)

摘　　要：某无缝钢管在磁粉检测过程中出现异常磁痕,采用热酸腐蚀试验、金相检验、扫描电镜和能谱分析、电子探针分析等方法对异常磁痕产生原因进行分析。结果表明:无缝钢管外壁存在明显带状成分偏析,成分偏析导致奥氏体稳定性提高,马氏体转变起始温度降低,使组织中出现残余奥氏体,造成磁粉检测过程中出现异常磁痕;这些磁痕沿螺旋方向分布,对材料的纵向力学性能和横向力学性能影响不大。Abnormal magnetic marks appeared in the magnetic particle testing process of a seamless steel pipe.The causes of abnormal magnetic marks were analyzed by hot acid corrosion test,metallographic examination,scanning electron microscopy and energy spectrum analysis,electron probe analysis and other methods.The results show that there was obvious banded composition segregation on the outer wall of the seamless steel tube.The composition segregation led to the improvement of austenite stability,the decrease of the initial temperature of martensitic transformation,the appearance of residual austenite in the microstructure,and the abnormal magnetic marks in the process of magnetic particle detection.These magnetic traces were distributed along the spiral direction,which had little effect on the longitudinal and transverse mechanical properties of the material.

关 键 词：无缝钢管 异常磁痕 偏析 残余奥氏体 热酸腐蚀试验 

分 类 号：TG115.28[金属学及工艺—物理冶金] TB31[金属学及工艺—金属学]