某车用变速器输出轴齿轮断齿失效原因分析

Analysis of Transmission Output Shaft Teeth Broken

针对某车用变速器输出轴发生断齿故障,借助扫描电镜、金相分析、硬度检测、X射线衍射等各种理化手段对失效原因进行了深入分析与研究。结果表明输出轴齿轮发生断齿是因齿轮心部硬度不够,影响齿轮的接触疲劳强度和弯曲疲劳强度,导致齿轮的齿在高应力作用下疲劳开裂。根据失效分析的结果,提出优化改进措施,最终确保零件顺利通过严苛的台架耐久试验。

The transmission output shaft of a vehicle had the problem of teeth broken.To address the problem,a thorough analysis and research on the failure cause was made by means of scanning electron microscope,metallographic examination,hardness tests,X-Ray,etc.The results showed that the failure was due to low strength in gear center,which effected the contacting and bearing fatigues,resulting in teeth crack under high stress.Several optimization measures based on the analysis results were proposed and implemented.As a result,the improved shaft passed the dyno durability tests successfully.