冲压板材拉伸筋阻力的一种有效数值计算方法

An Effective Numerical Method for Drawbead Force of Stamping Sheet Metals

将弹塑性有限变形的拟流动角点本构理论和厚向各向异性屈服函数引入弹塑性动力显式有限元列式，对板材通过拉伸筋的变形过程及拉伸筋阻力进行了数值模拟，并与有关实验结果进行了比较，显示了很好的一致性，表明了该计算方法的有效性。进而，数值研究了拉伸筋形状、界面摩擦状况以及材料的厚向各向异性对拉伸筋阻力的影响，为实际覆盖件冲压成形中拉伸筋的设置提供了重要的定量依据。

A quasi-flow corner constitutive theory and a normal anisotropic yield function are introduced into dynamic relaxation explicit finite element formula. The deformation process of sheet metal passing through drawbead and the drawbead restraining force are numerically simulated. The simulated results are compared with experimental ones. Good agreement is shown and the validity of the present method is proved. Furthermore, the influence of drawhead shape, interface friction and normal anisotropy on drawbead restraining force is numerically studied in order to provide quantity reference for the lay-out of drawbead in practical panel stamping forming.