基于GTN细观损伤模型的激光拼焊板成形极限预测

建立了从细观损伤角度预测拼焊板成形极限的Gurson-Tvergaard-Needleman(GTN)损伤模型,用有限元逆向法确定了损伤模型中的各损伤参数。采用有限元软件ABAQUS耦合基于Mises屈服准则的弹塑性GTN损伤模型，对拼焊板半球凸模胀形过程进行了数值模拟。设计了拼焊板半球凸模胀形物理试验，试验过程中通过改变试件的宽度得到了不同应变状态下完整的拼焊板成形极限图，并与GTN细观损伤模型预测到的拼焊板成形极限图进行对比分析，验证了GTN细观损伤模型预测拼焊板成形极限图的准确性。

Forming Limit Prediction of Tailor-welded Blanks Based on GTN Damage Model

The  GTN  damage model was established to predict the forming limit of TWBs,and the damage parameters were determined by the use of finite element inverse method. Hemispherical punch bulging test process was simulated by the finite element software ABAQUS and coupled the Mises yield criterion with GTN damage model. Experiments of hemispherical punch bulging test were  designed,which changed specimen width to obtain complete forming limit diagram of TWBs in different strain conditions.Meanwhile, the prediction and experimental results were compared to validate the accuracy of GTN damage model.