On the induction heating contribution in magnetic pulse forming processes for tube forming application

Abstract

Purpose The purpose of this paper is to study the influence of the induction heating phenomenon during magnetic pulse forming (MPF) of thin walled tube components. The approach is based on the advanced use of the multiphysics finite element software FORGE® coupling electromagnetism, heat transfer and solid mechanics. Although the global contribution of thermal effects is found to be almost negligible with respect to the volume forces, it can be observed that localized softening due to the heating process induces shock absorbing behavior. Design/methodology/approach Due to the strong multiphysics couplings between solid mechanics, electromagnetism and heat transfer, it is not always obvious to quantify the contributions of the various physical phenomena. It is thus intended here to take advantage of the numerical framework and tool that has developed to dissociate and quantify the influence of Joule heating phenomena due to eddy currents during MPF processes. Findings In this paper, the sensitivity of the MPF process has been analyzed to the induction heating source term for a specific tube forming case. An analysis of the electric output signal shows that inductance sensitivity to heating remains small when compared to the mechanical deformation. Regarding mechanical analysis of the process, induction heating contribution has a very slight impact at the global scale, but its effect is more noticeable at the small scale where it is likely that the localized heating induces shock absorption properties through softening. The extension of these results to other materials (for which the thermal dependency of mechanical behavior is different), as well as to a larger range of energy inputs, still needs to be carried out. Such phenomena should be considered for instance for high precision forming. Originality/value The analysis of the influence of heating due to eddy currents in magnetic pulse forming processes has not been extensively studied. The originality of this work is to try to quantify its effect on the process by using a numerical-based approach.