树脂复合减振钢板U型弯曲回弹实验与数值模拟研究

通过带法兰边的U型弯曲成形实验研究,考察了树脂复合减振钢板在不同压边力下的回弹特性.实验结果表明:压边力对树脂复合减振钢板回弹特性影响显著.较大的压边力有利于减小回弹缺陷.其次,考虑树脂层的粘弹性特性,采用非线性粘弹性模型来描述树脂层的力学变形行为,并采用Cohesive单元和固体壳单元分别对树脂层和表层钢板进行离散,进行了树脂复合减振钢板在不同压边力下的U型弯曲有限元数值模拟研究.和实验结果比较表明,所建立的有限元模型能够较好的模拟U型弯曲成形过程.最后,基于建立的有限元模型,考查了成形速度,树脂层厚度和表层钢板初始屈服应力对回弹的影响.参数分析结果表明:这三个参数对回弹角的影响显著.该研究对树脂复合减振钢板冲压工艺设计具有一定的指导意义.

Experiment and numerical simulation of springback of laminated steel sheet in U-channel forming process

U-channel forming experiment of laminated steel sheet is conducted to investigate springback characteristics in different blank hold force.The result indicates that blank hold force significantly affects springback.Large blank hold force can reduce the springback.Considering the visco-elastic properties of polymer layer,a nonlinear visco-elastic material model is implemented to describe the polymer layer deformation during the numerical simulation of U channel forming process.Cohesive element and continuum shell element are implemented to discrete the polymer layer and face steel sheet,respectively.Result indicates that the finite element model can simulate the U channel forming process very well.Finally,a parametric study of the dependence of springback on variation of forming speed,thickness of polymer layer and initial yield stress of face steel sheet is performed using this finite element model.The parametric study result shows that those three parameters are significantly affect the springback.