金属板料二次成型的有限元分析

Finite element analysis for twice metal formings

为了实现同台压力机加工多品种、多型号的板料,大型板料的成型采用同机分步成型,通过采用板料成型动力显式有限元模拟,采用四节点退化壳单元对板料进行离散化,利用中心差分法离散时间域,建立动力显式计算格式,采用罚函数法和修正库仑定理计算接触力和摩擦力。对二次成形过程,建立有限元分析计算模型,通过Dynaform软件仿真得出同机分步成形法的可行性。

The separate dies and different-step sheet ize the processing of multiple varieties and multiple metal forming is applied to big blank forming to realmodels on the same pressing machine. A finite element model for dynamic analysis of sheet metal forming process is elaborated in this paper. Four-node degenerated shell elements are adopted to discretize sheet metal. The central difference is set up. Penaltv method is employed to calculate normal contact force and revised Coulumbic friction law is employed for modeling friction. Finite element computing model is set up for the processes of two metal formings. The feasibility of separate dies and different-step sheet metal forming is certified by using the software of Dvnaform.