冰箱压缩机限位器断裂失效分析

Fracture failure analysis on the limiter of refrigerator compressor

对冰箱压缩机的限位器进行了断裂失效分析。通过对断裂的限位器进行外观检查、断口分析、成分测试、物相鉴定、硬度检测、渗层厚度测量及金相分析,并对限位器使用时的受力进行分析,确定了限位器的裂纹源、断裂性质和断裂原因。结果表明:失效限位器属于疲劳断裂,导致疲劳断裂的原因是限位器在压缩机运行过程中产生了较大幅度的振动弯曲并且断裂位置处存在应力集中。并提出了提高该限位器可靠性的几个改进建议。

Thefractured limiter of a refrigerator compressor was analyzed.The source of crack,failure mode and cause were found out byvisual inspection,fracture analysis,chemical compositionanalysis,phase analysis,hardness test,nitridinglayer thickness measure,metallographic examination as well as force analysis of the limiter.The results indicate that the fracturing of the limiter is fatigue fracture.Large vibration bending and stress concentration at the fracture site during the process of operation are the cause of fracturing.Finally,some suggestions and measures were put forward to improve the reliability of the limiter.