Electromagnetic forming tools and processing conditions: Numerical simulation

Finite element (FE) modeling is used to simulate the electromagnetic forming process. Two industrial tools are considered: a four-turn compression coil with a ferromagnetic screen and a stepped field shaper as well as a seven-turn pancake coil with a ferromagnetic outer screen. Details on FE model building are thoroughly discussed. The input load is the current of the coil, which can be experimentally measured. The deformation characteristics of the workpiece as well as the electromagnetic variables of the high-energy rate process (i.e., the magnetic flux density around the conductors and the Lorentz forces acting on the workpiece) are calculated numerically. The effects of the various parameters of the electromagnetic forming process, such as initial charging voltage, workpiece material, and geometry as well as holding devices, are analyzed either theoretically or through FE modeling. In most cases, the dependent variable is the Lorentz force acting on the workpiece. The numerically calculated and analytical electromagnetic results are in good agreement. The present analysis is useful for the practical realization of the electromagnetic forming process, contributing also to a better understanding of its principles.