【摘要】 板材软模成形是板材和柔性传力介质耦合变形过程,存在板材和刚性模具及板材和柔性传力介质两种类型的界面接触。采用罚函数法计算接触力,推导了Mindlin轴对称壳单元和实体单元两种不同单元类型之间接触摩擦的有限元列式。采用静力显式的时间积分方法,通过控制载荷步长保持接触状态稳定。粘弹塑性软模材料的板材变形数值算例表明该算法是有效的。该算法也适用于其他类型软模材料的板材变形接触摩擦问题的处理。更多还原

【Abstract】 Sheet metal flexible-die forming process is the combination of sheet metal deformation and flexible-die deformation. Contact description can be differentiated into two categories, contact between sheet metal and rigid die, and contact between sheet metal and flexible pressure-carrying medium. The penalty function method is used to evaluate the contact force and a finite element formulation and solution algorithm are developed to solve the contact problem between two different type element: Mindlin axisymmetric shell element and solid element. The static-explicit time integration algorithm is employed to limit the incremental step to a size, which will keep the contact state steady. It is illustrated through analyzing the sheet metal deformation by applying the visco-elastoplasticity as flexible pressure-carrying medium that the solution algorithm is valid. The solution algorithm developed can also be used to solve the frictional contact between sheet metal and other type flexible pressure-carrying medium.更多还原