考虑空洞效应的板料超塑性成形数值模拟

Numerical Simulation of Sheet Superplasticity Forming Coupling Cavity Effect

本文基于弹粘塑性理论,推导出考虑空洞效应的超塑性流动本构方程,对板料超塑性拉伸进行了模拟研究,获得的应力应变曲线具备超塑性材料的流动特征,这表明新本构模型能够较好地描述超塑性流动特性;同时基于新本构模型对板料自由胀形过程进行了数值模拟,研究了各变形阶段的厚度分布,并与Backofen模型的计算结果进行了比较。

A new constitutive model coupling cavity effect based on elastic-viscoplasticity theory has been deduced. The stress-strain curve obtained in sheet superplasticity stretch simulation based on new constitutive has had superplastic flow characteristic, indicating that the new constitutive can describe the superplastic flow characteristic preferably. Sheet freedom bulging has been simulated, the thickness distribution during various deforming phases of the sheet using the new constitutive been studied and compared with Backofen model.