等效拉延筋模型对回弹预测的影响

Influence of equivalent drawbead model to springback prediction

等效拉延筋模型是影响回弹预测结果的一个重要因素。结合拉延筋试验、拉延筋试验的仿真以及拉深的仿真,研究了等效拉延筋模型对回弹预测结果的影响。结果显示,板料经过拉延筋后,出现材料硬化、变薄,并且有因横截面应力形成的力矩;仿真中采用等效拉延筋模型时,对板料经过拉延筋后出现的这些现象都不能准确地模拟。板料的硬化、在板料横截面的力矩,对工件的回弹预测结果影响显著。板料的横截面力矩的准确描述,对回弹预测的精度尤其重要。为了提高回弹的预测精度,有必要提出修正的等效拉延筋模型。

The equivalent drawbead model is a key factor that affects the precision of springback prediction. The influence of the equivalent drawbead model to springback prediction is studied based on the drawbead test, the simulation of drawbead test and the simulation of deep drawing process. Results show that the blank is stiffened, the thickness is reduced and stress forming a moment is retained. Using the equivalent drawbead model, the test results cannot be observed in the simulation results. The modified material parameter, and the moment formed by the stress on the traversal section of blank have great effect on the springback prediction, especially the moment. It is necessary to propose a modified equivalent drawbead model to improve the precise of spring-back prediction.