重型车辆变速器齿轮轮毂断裂失效分析及改进措施

Failure Analysis and Improvement Design for Abnormal Fracture of Heavy Vehicle Transmission Gear Hub

针对变速器一挡主动齿轮在试验过程中发生断齿这一早期失效问题,进行了失效齿轮轮毂的化学成分检验、断口分析和金相组织形貌检测分析等失效机理研究。分析结果表明,花键槽圆角过小、轮缘厚度不足及齿根喷丸强化不足是造成失效齿轮轮毂异常断裂的主要原因。采用有限元建模进行失效齿轮的接触应力分析,并提出了改进措施。

For early failure problem of broken teeth of the first driving gear for gearbox in testing process,the failure mechanisms such as chemical composition inspection,fracture surface analysis as well as the metallographic structure morphology inspection analysis of failure gear hub are carried out.The results show that the main reasons causing abnormal fracture of the failure gear are the insufficient root strengthening of shot peening,the small groove fillet of the spline and the inadequate rim thickness.Using the finite element modeling,the contact stress analysis of failure gear is carried out and an improvement design method is put forward.