非对称型材拉弯成形的数值模拟研究

基于非线性有限元软件MSC.Marc对某汽车门框复杂截面型材的拉弯回弹进行了数值模拟研究。首先以切边模型为例对复杂截面型材有限元拉弯模拟做了详细的分析,提出了回弹半径和回弹间隙两种回弹参数评价,分析了模具半径和预拉力对回弹的影响。然后针对容易起皱的底面提出了一种失稳判定准则,并把复杂截面拉弯成形后的起皱区域划分为三部分,结合MSC.Marc软件的二次开发功能给出了描述失稳程度大小的用户变量曲线图。复杂截面型材拉弯成形的缺陷参数处理,最主要的就是回弹和起皱,有限元数值模拟对汽车型材拉弯件的成形质量、生产效率等都具有重要的指导意义。

Numerical simulation study in stretch bending process for symmetrical section profile

A stretch bending numerical study on one complicated car sub-frame profile using nonlinear FEM software MSC.Marc is presented. Firstly, the bending finite element simulation of the complicated section profile is analysed detailedly as the example of the cutting-edge model. Two rebounding assessment parameters including the rebounding radius and the rebounding gap are proposed. And the effect of the model radius and the Preload on the rebounding is also analysed.Then for the bottom which is easily wrinkled, the destabilization judgement criterion is proposed. And the stretch bending of complex cross-section area after the wrinkle is divided into three parts, with secondary development of software MSC.Marc ,the user variable curve is given to describe the instability degree. For the defect parameters treatment of the complicated section profile, the most important is the rebounding and wrinkling. The finite element simulation of vehicle parts profile can be the guidance to the product quality and the productivity.