60Si2MnA钢簧片失效分析及热处理工艺

Failure analysis and heat treatment of 60Si2MnA steel leaf spring

对60S i2MnA钢簧片分别进行普通淬火、真空淬火、薄层渗碳复合热处理试验,采用回零试验检验零件弹性合格情况,并测试了力学性能和表面残余应力。结果表明,簧片经复合热处理后合格率最高,普通淬火由于表面脱碳零件合格率最低,真空淬火因为淬火强化效果降低合格率一般。簧片失效原因在于热处理表面质量差,加载后表面产生塑性变形。薄层渗碳复合热处理工艺能改善簧片表面质量及性能,特别是提高了表面残余压应力,有效地提高了产品合格率。

60Si2MnA steel leaf springs were heat treated by conventional quenching,vacuum quenching combined heat treatment of thin layer carburization respectively,the quality was tested by adopting return-to-zero trial,mechanical properties and surface residual stress were measured.The results show that the qualified rate of the samples by combined heat treatment is highest,that by conventional quenching is lowest because of the decarburization on surface,that by vacuum quenching is middle because of the low hardened effect.The leaf spring failure reasons mainly attribute to the poor surface quality,which cause to plastic deformation.Thin layer carburization before quenching can improve the surface quality and mechanical properties,especially improve surface residual pressure stress,and increase products qualified rate effectively.