Fully coupled numerical analysis of high frequency induction heating and warm sheet metal forming

The present study aims to develop a warm forming process for an aluminum alloy sheet to reduce weight of an electric housing part. Considering that the target product is produced through a series of metal forming processes using a progressive die, high frequency induction heating is proposed to heat a specific drawing punch locally and rapidly, out of a series performed using a progressive die. To validate the effect of the induction heating on the formability improvement of aluminum alloys, a fully coupled numerical simulation is proposed: (i) finite element (FE) analyses for the multi-stage deep drawing processes are performed to predict formability at each stage; (ii) electrostatic-thermal coupled FE analysis is performed to predict the temperature rise of the drawing punch; and (iii) thermo-mechanical coupled analysis is conducted to investigate the effect of induction heating on the formability change. Through the proposed coupled simulation, it is proven that the drawing punch can be efficiently heated without a significant increase in cycle time, and the corresponding drawing process using aluminum alloys can be successfully performed without forming failure.