轮辐冲压工艺优化及起皱控制方法

Optimization of spoke stamping process and wrinkle control method

针对高强度车轮钢采用多道次成形或热成形工艺而导致生产成本高、生产效率低等问题,以某商用汽车轮辐为研究对象,通过减少冲压道次,改进现有冲压方案,分析板料冲压起皱临界状态以及压边力的变化规律,预测起皱位置,确定抑制起皱缺陷的冲压工艺参数,并对轮辐冲压成形过程进行模拟仿真,通过优化模具结构以及添加局部拉延筋改变冲压时材料的流动阻力,改善起皱与减薄等缺陷,并对优化后的工艺方案进行试验验证。结果表明:豁口处材料缺失使各区域所需压边力不同是导致起皱缺陷的主要原因,改变模具结构并添加拉延筋后,轮辐成形质量良好,起皱缺陷得到抑制,优化后产品减薄率控制在5%。

In response to the problems of high production costs and low production efficiency due to the use of multi-pass forming or hot forming processes for high-strength wheel steel,for a commercial vehicle wheel spoke,by reducing the number of stamping passes and improving the existing stamping scheme,the critical state of sheet metal stamping wrinkling and the change rule of blank holding force were analyzed,and the wrinkling position was predicted.Then,the stamping process parameters to suppress wrinkling defects were determined,and the stamping process of wheel spoke was simulated.Furthermore,by optimizing the die structure and adding local draw beads to change the flow resistance of material during the stamping process,the defects such as wrinkling and thinning were improved,and the optimized process scheme was experimentally verified.The results show that the material absence at the notch makes the blank holding force required in each area different,which is the main cause of wrinkling defects.After changing the die structure and adding draw beads,the forming quality of wheel spoke is good,the wrinkling defect is suppressed,and the thinning rate of the optimized product is controlled within 5%.