双毂倒挡齿轮温锻成形金属流变行为及工艺研究

Analysis of Metal Flow and Process of Back Gear with Double Boss in Warm Forging

根据齿部带有倒锥的双毂倒挡齿轮结构特点,提出了一种两步温锻+冷精整的新工艺。以某双毂倒挡齿轮零件为例进行实验发现齿形下角隅充填不满,为解决此问题建立了齿轮温锻成形过程的刚塑性有限元仿真模型,分析了其速度、应力与应变等场量信息,结合盐酸热蚀后的金属流线探讨了成形过程中金属的流动规律,通过在模具上设置凹槽增大金属径向扩展"波形"最终使得轮齿角隅充填饱满。齿轮测量仪检测结果表明:采用提出的新工艺能够获得满足双毂倒挡齿轮要求的轮齿齿形。

Based on the geometric features of back gear with double boss,a new two-step warm forging process before finishing was put forward to reduce the number of cold forging process.Empty corners in the bottom of profile of all teeth were found when using the above process.In order to solve the problem,a rigid plastic FE model was built to simulate the warm forging process.The velocity,stress and strain field were investigated,and the metal flow rules were discussed with the experimental results.Then a qualified gear was achieved through expanding the radial wave shape by means of an indentation established in die.The measured results show that the new process can satisfy a high level precision of forging.The work presented herein may be used as basic data for the design of the precision forging processes.