汽车减振器活塞杆断裂原因  

Fracture causes of piston rod of automobile shock absorber

作　　者：李明 LI Ming(Testing Center,Jinzhou Jietong Railway Machinery Co.,Ltd.,Jinzhou 121116,China)

机构地区：[1]锦州捷通铁路机械股份有限公司检测中心,锦州121116

出　　处：《理化检验（物理分册）》2024年第11期71-74,共4页Physical Testing and Chemical Analysis(Part A:Physical Testing)

摘　　要：某型汽车减振器活塞杆在进行弯曲试验时发生异常断裂现象。采用宏观观察、化学成分分析、扫描电镜和能谱分析、金相检验、硬度测试等方法对其断裂原因进行分析。结果表明:活塞杆在镀铬工艺中吸入了氢元素,经除氢处理后未充分逸出,氢元素在高频淬火区的夹杂物处聚集,形成氢致裂纹,在弯曲应力的作用下,裂纹不断扩展,最终导致活塞杆发生脆性断裂。A certain type of automobile shock absorber piston rod experienced abnormal fracture during bending test.The fracture cause was analyzed using macroscopic observation,chemical composition analysis,scanning electron microscopy and energy spectrum analysis,metallographic examination,hardness testing.The results show that the piston rod absorbed hydrogen elements during the chrome plating process,but did not fully escape after hydrogen removal treatment.Hydrogen elements gathered at the inclusions in the high-frequency quenching zone,forming hydrogen induced cracks.Under the action of bending stress,the cracks continued to propagate,ultimately led to brittle fracture of the piston rod.

关 键 词：活塞杆 镀铬 氢脆 氢致裂纹 脆性断裂 

分 类 号：TB31[一般工业技术—材料科学与工程] TG115.2[金属学及工艺—物理冶金]