On the effect of current pulses on the material behavior during electromagnetic metal forming

Abstract

Electromagnetic sheet metal forming (EMF) is an example of a high-speed forming process driven by the dynamics of a coupled electromagnetic-mechanical system. Basic physical processes involved in EMF, such as e.g. inelastic and hardening behavior or inertia, have been considered in previous works [1, 2]. The purpose of the current work is the investigation of temperature development during EMF and a possible reduction in the yield stress due to electric currents. While thermoelastic and viscoplastic effects are well-understood in this context [3], the possible influence of electric currents on dislocation motion, generally referred to as the electro-plastic effect [4, 5], is still an unresolved issue. In agreement with previous works [e.g., 6], it is concluded here that such an effect is at most of second-order and can most likely be safely neglected in the modeling and simulation of industrial EMF.