乘用车稳定杆耐久试验断裂失效分析

Failure Analysis on Fracture of Vehicle Stable Bar in Durability Test

某新开发车型的SUP9钢制实心稳定杆在耐久试验过程中发生断裂失效。采用断口分析、化学成分分析、硬度测试、金相检验等方法分析了稳定杆失效的原因。结果表明:失效稳定杆的断口为典型的疲劳断口,稳定杆存在严重的脱碳问题,导致稳定杆出现早期疲劳裂纹起源并扩展,最终稳定杆发生疲劳断裂失效。

A new developed SUP9 steel solid stable bar fractured and failed in the process of durability test.The failure causes of the stable bar were analyzed by means of fracture analysis,chemical composition analysis,hardness test and metallographic examination.The results show that the fracture of the failure stable bar was a typical fatigue erack fracture.There was a serious decarburization problem in the stable bar,which led to the early fatigue crack initiated and expanded of the stable bar,and finally to fatigue fracture failure of the stable bar.