Finite element simulation of the electromagnetic piercing of sheet metal

In the paper, the sheet electromagnetic piercing process is analyzed from a dynamic view. 3D non-linear simulation is undertaken by means of a dynamic explicit finite element method. Patterns of stress distribution, deformation, kinetic energy, and equivalent rigid velocity have been obtained. According to the different characteristics of deformation and using the von Mises stress distribution condition, the forming of the workpiece can be divided into four phases. In phase I, stress extends to the center of the workpiece gradually, showing a distinct circular wave. In phase II, the drawing of the workpiece increases gradually and the workpiece zone near to the die blade becomes highly stressed and high radial elongation occurs. In phase III, rupture occurs. The high stress zone changes to the center of the waste sheet with little displacement, but there is great bending deformation. In phase IV, inertial emission of waste sheet starts and bending deformation of the waste sheet continues to extend to its center. It is established that the method has substantial feasibility. The present work affords a sound theoretical basis for further work.