汽车侧门外板成形的工艺优化策略

Optimization strategy of outer panel forming process of automobile side door

针对汽车侧门外板在拉延生产中出现的厚度减薄过大、切边后回弹较大的缺陷,采取统计学及试验设计相关理论,结合有限元模拟技术,以产品最大变薄率和回弹量为优化目标。采用正交试验及其极差法筛选出重要的影响参数:对压边力和拉深筋高度,以中心复合设计法(CCD)建立优化目标和关键参数的二次回归模型;以线性加权和法构建双目标的综合评价响应曲面函数,得到了压边力和拉深筋高度的最优解。经数值模拟及生产实践验证,产品区域最大变薄率减小了13.61%,回弹量减少了1.83°,产品的强度和精度得到了提高。

For the production defects including the large thinning rate during the drawing process and the springback after cutting,statistics theory,DOE and finite element simulation technology were applied,with the largest thinning rate and springback as the optimization targets.First the orthogonal test and range method were employed to screen out important parameters： blank holder force（BHF） and drawbead height.Central composite design（CCD） method was used to establish the square regression model for target optimization and the key parameters.Finally the comprehensive evaluation of response surface function was constructed for double targets with the method of linear weighted plus.The optimal solution of BHF and drawbead height was obtained.After verification by numerical simulation and production practice,the maximum thinning rate was reduced 13.61%,and the springback was reduced 1.83°.Therefore the strength and the precision of products were improved.