Electromagnetic Modelling & Experimental Analysis of Weld Tool Coil in Magnetic Pulse Welding

Abstract

Magnetic Pulse Welding (MPW) is a high-velocity, solid-state welding technique utilized to join dissimilar metals through the application of a strong magnetic field. The MPW system comprises a 208 µF capacitor bank and a specialized weld tool coil. In this study, the capacitor bank was charged up to 11 kV, resulting in a discharge current of 100 kA at a frequency of 12.5 kHz through the tool coil. The weld tool coil is designed with six 6-turn copper discs and is integrated with a copper field shaper to enhance the welding process. This paper presents the development of a two-dimensional (2-D) model using COMSOL Multiphysics to analyze the impact of the field shaper on the magnetic field intensity generated by the 6-turn coils. Simulation results revealed that the discharge current of approximately 100 kA at 12.5 kHz produced an average magnetic field intensity of around 29 Tesla (T). The field shaper effectively concentrated the magnetic flux within a smaller, targeted region of the workpieces. The inclusion of the field shaper in the coil's axis led to an approximate fourfold increase in the magnetic field intensity, thereby demonstrating its significant role in enhancing the efficiency of the MPW process.