乘用车60Si2MnA螺旋弹簧的断裂失效分析  

Fracture Failure Analysis of 60Si2MnA Spiral Spring for Passenger Cars

作　　者：刘晓丽[1] LIU Xiaoli(College of Mechanical Engineering,Shangqiu Insititute of Technology,Shangqiu 476000,China)

机构地区：[1]商丘工学院机械工程学院,河南商丘476000

出　　处：《热加工工艺》2020年第8期158-159,164,共3页Hot Working Technology

摘　　要：某乘用车60Si2MnA螺旋弹簧在使用过程中出现了断裂,对此进行了失效分析。结果表明:螺旋弹簧的材料成分、硬度均符合相关技术要求;利用扫描电镜对断口进行分析,裂纹起源于次表层位置,且没有夹杂物;对显微组织进行分析,弹簧表面存在约0.38 mm的脱碳层。由于脱碳层的硬度较低,在受到外力作用时容易引起塑性变形,这是导致弹簧断裂的主要原因。对弹簧的热处理工艺进行了改进,避免了显微组织的脱碳,有效解决了螺旋弹簧的断裂问题。The 60Si2MnA spiral spring of a passenger car was broken during use,the failure analysis was carried out.The results show that,the material composition and hardness of the coil spring are in accordance with the relevant technical requirements.The fracture surface is analyzed by scanning electron microscopy.The crack originates in the subsurface,and there is no inclusion.The microstructure is analyzed.A decarburized layer of about 0.38 mm is on the surface of the spring.Because the hardness of the decarbonization layer is low,plastic deformation can be easily caused when it is subjected to external force,which is the main cause of the spring break.The heat treatment process of spring is improved to avoid the decarbonization of microstructure and solve the fracture problem of spiral spring effectively.

关 键 词：螺旋弹簧 脱碳 60SI2MNA钢 失效分析 疲劳裂纹 

分 类 号：TG111.91[金属学及工艺—物理冶金]