板材成形过程中直拉深筋作用的数值模拟

Numerical Simulation for Sheet Metal Deformation in a Straight

本文通过对板料在直拉深筋中变形过程的分析,给出了一个简化的直拉深筋作用分析模型.针对这个模型建立了有限变形弹塑性有限元方程,并利用所编制的程序计算了半圆形截面和方形截面直拉深筋作用下板料的变形.实验表明数值分析结果是可靠的.

A simple model for analyzing sheet metal deformation in a straight drawbead is presented and the corresponding formulation of the finite strain elastic-plastic FEM is derived. Sheet metal deformation in a straight drawbead during the sheet metal forming process can be divided into two stages: the plane strain forming in the straight drawbead and pulling through the drawbead. General assumptions of the shell theory are applied to the model and the normal stress of sheet metal is assumed to be equal to zero. Normal anisotropy of sheet metal is considered. The friction between sheet metal and tool surfaces is assumed to satisfy the Coulomb friction law. Some results of numerical simulation for sheet metal deformation in straight drawbeads with semi-circular and rectangular cross-sections are given. The results of simulation are in good agreement with those obtained by experiment.