板料形状、压料筋的设置对汽车覆盖件成形中起皱和未充分拉深的影响

The Influence of blank shape and the setting of drawbead on wrinkling and inadequate stretch areas in automobile covering parts forming processes

在汽车覆盖件成形工艺中,无论是对外观还是对功能的要求,起皱和未充分拉深问题是不允许出现的,因此对起皱和未充分拉深问题的预测和防止显得非常重要的。采用数值模拟技术可以在模具设计初期预测产品的几何形状,从而优化工艺参数以便获得高质量的成品。文章以eta/DYNAFORM有限元分析软件为平台,采用弹-塑性有限元法对DDQS钢进行数值模拟,得出相应的FLD曲线、起皱和未充分拉深区域。重点探讨了板料形状和压料筋的设置对起皱和未充分拉深区域的影响,得出了较好的解决方案。

Prediction and prevention of wrinkling and inadequate stretch areas are extremely important in the design of process pa rameters in automobile covering part forming processes. Wrinkling and inadequate stretch areas are usually undesired in final sheet metal parts for aesthetic or functional reasons. Therefore, the prediction and prevention of them are extremely important in sheet metal forming. Numerical simulation is applied to check part geometry at an early stage of design, as well as to optimize the shape parameters for a safe production, especially in the automotive industry. In this study, the numerical results are based on eta/DYNAFORM finite element analysis （FEA） software using elasto-plastic flow method. This general purpose of FEA code is using explicit dynamic procedure. The model is employed to predict the strain forming limit diagrams and wrinkling behavior of a deep drawing quality steel （DDOS）. An effective scheme of changing blank shape and the setting of drawhead to optimize stam- ping quality is carried out, by minimizing the risk of wrinkles and inadequate stretch areas.