多道次变薄拉深的模拟与优化设计

The Simulation and Optimization of MultiStep Lroning Process

多道次变薄拉深将成形过程分为几个子过程顺次完成，成形次数和各道次变薄量的分配对成形过程能否顺利完成以及产品质量具有重要影响，本文建立了多道次变薄拉深变薄区的刚塑性有限元模型，对其工艺过程进行了模拟分析。提出了承载裕度的概念，建立了多道次变薄拉深各道次变薄量分配关系优化设计的目标函数与约束条件，由此建立了一种给定总变薄量与变薄次数后，确定各次变薄量分配关系的最优化设计方法。

Multistep ironing process is composed of several subprocesses. The deformation varies from subprocess to subprocess. The deformations of all the subprocesses taken together form a “deformation path”, which exerts great influence on the multistep ironing process. We divided the deformation body into successive ironing zones and proposed a finite element method (FEM) to analyze the multistep ironing process. We proposed loading allowance to describe the loadbearing capacity of each ironing zone. We derived eq.(18) to optimize the ironing steps and thickness reduction of each step. Eq.(18) contains an objective function and satisfies restraint criteria based on keeping the loading allowance of each ironing step to be the same. Our results reveal that our optimization method is feasible.