车用齿轮轴冷挤压成形模拟及反挤压工艺参数优化

摘要

针对车用齿轮轴制定了冷挤压成形工艺方案,并对其进行了相应的正、反挤压模具设计.利用Deform-3D进行有限元仿真模拟,对成形件进行等效应变、等效应力、损伤和载荷—行程曲线分析.选取凸模速度、摩擦因数以及凸模锥角3种工艺参数进行正交试验及工艺优化,通过正交试验的方差分析得出摩擦因数对齿轮轴反挤压载荷大小具有显著影响,并得到各参数对成形载荷的影响顺序为:摩擦因数>凸模锥角>凸模速度.最终得到的最优反挤压工艺参数为:凸模速度为25 mm/s、摩擦因数为0.10和凸模锥角为25°.优化后反挤压的最大载荷由原来的2.15×104kN减小到1.01×104kN,降低了53个百分点.%A cold extrusion process was developed for the gear shaft of the vehicle and the corre-sponding forward and backward extrusion die design were carried out.The analysis of equivalent strain,equivalent stress,damage and load-stroke curve of the forming part were analyzed by the finite element simulation based on Deform-3D.The effects of punch velocity,friction coefficient and punch angle were selected for orthogonal experiment and process optimization.The variance a-nalysis of the orthogonal test shows that the friction coefficient has a significant effect on the back-ward extruding load of the gear shaft and the order of influence of each parameter on the forming load is as follows:friction coefficient>punch angle>punch velocity.The optimal parameters of backward extrusion process were obtained finally:punch speed is 25 mm/s,friction coefficient is 0.10 and punch angle is 25°.The maximum load of the optimized backward extrusion is reduced from 2.15×104kN to 1.01×104kN,which drops 53%.