采用薄膜模型模拟三维板料成形过程

Simulation of Three Dimensional Sheet Metal Forming Process by a Membrane Shell Model

此文基于有限变形理论建立了三维金属板料成形过程的弹塑性有限元数学模型。数学模型采用物质坐标系中的Total Lagrange描述、J_2型本构方程、等向强化假设,考虑了板料的厚向异性,对于金属板料与模具的摩擦采用近似的库仑摩擦定律以改善计算的收敛性。为简化计算采用薄膜单元。采用根据此模型编制的程序模拟了机油收集器基本件的成形过程,并与实验结果进行了对比。

Based on the finite deformation theory and elastic-plastic membrane theory, a finite elementmodel for simulation of three dimensional sheet metal forming process is developed. In the molel,Total Lagrangian formulation in material coordinate system and Jz tgpe incremental constitutive relation in general curvilinear coordinate system are adopted. Isotropic hardening and anisotropy in the normal direction of sheet material are assumed. To improve the stability of numerical computation,the approximate Coulomb friction law is used at the contacting surfaces between sheet metal and punch or die,and modified Newton iteration is adopetd. Numerical results obtained from application of our finite element code to the forming process of an oil collector are compared with experimental data.