铜铝复合板渐进成形回弹缺陷研究

Research on Springback Defects in Incremental Forming of Cu-Al Bimetal

为了讨论不同工艺参数对复合板渐进成形回弹的影响,建立了包含工具头、复合板材和复合界面的三维有限元模型,通过对比T形剥离结果得到复合界面内聚力单元参数,通过实验验证了有限元模型的可靠性。实验结果表明,成形角对双金属复合板渐进成形回弹最敏感,工具头直径对回弹敏感度最低,另外,内聚力单元能有效模拟双金属复合板结合界面,模拟误差仅为7.9%。分析结果表明,单层下压量、板厚、工具头直径都与回弹量成正相关,成形角与回弹量成负相关,成形角从30°增大至60°时回弹量减小21%。

In order to discuss the influences of different processing parameters on springback in incremental forming of bimetals,a three-dimensional model was established including the tool head,laminated sheet and composite interface.The parameters of the interface cohesion elements were obtained by comparing the results of T-peeling,and the reliability of the finite element model was verified through experiments.The experimental results show that the forming angle is the most critical factor affecting the springback,and tool diameter is least sensitive to springback.In addition,the cohesive element may effectively simulate the interface of the laminated sheets,and the simulation error is only 7.9%.The analysis shows that the step-down size,sheet thickness and tool diameter are positively related to the springback values,the forming angle is negatively related to the springback ones.And the springback value decreases by 21%as the forming angle increases from 30°to 60°.