4140悬挂器磁粉探伤裂纹检验分析  

Inspection analysis of cracks in 4140 hanger by magnetic particle flaw detection

作　　者：刘昌乐 陈昌华 施虹屹 杨诚 陈新华 LIU Changle;CHEN Changhua;SHI Hongyi;YANG Cheng;CHEN Xinhua(Technology Center,Nanjing Develop Advanced Manufacturing Co.,Ltd.,Nanjing 210048,China)

机构地区：[1]南京迪威尔高端制造股份有限公司技术中心,江苏南京210048

出　　处：《物理测试》2021年第1期56-59,共4页Physics Examination and Testing

摘　　要：材料4140悬挂器锻件经精加工后进行表面磁粉探伤,发现其端面有裂纹。为查明裂纹原因,对其进行解剖取样检验分析。结果表明:裂纹是在淬火或回火之前形成的,属于淬火组织应力引起的端部裂纹,裂纹大部分处于深色偏析条带中,表明深色偏析条带是裂纹形成原因之一,裂纹主要以沿晶扩展,并与深色偏析条带区中微量有害元素沿晶界析出有关。The material 4140 hanger forgings were subjected to surface magnetic particle inspection after finishing,and the cracks were observed on the end surfaces. In order to find out the causes,the anatomical sampling inspection and analysis were carried out. The results showed that the cracks were formed before quenching or tempering,and belonged to the end cracks caused by the stress of the quenched structure. Most of the cracks were located in the dark segregation bands,indicating that dark segregation band was one of the causes of crack formation. The crack was mainly propagated along the grains,and it was related to the precipitation of trace harmful elements along the grain boundaries in the dark segregation band.

关 键 词：4140材料 裂纹 磁粉检测 金相检验 断口分析 

分 类 号：TE931.2[石油与天然气工程—石油机械设备] TG115.28[金属学及工艺—物理冶金]