Accelerated Plasma Spraying of Cu/Alumina Ceramics Based on Electromagnetic Pulse Welding: Simulation and Experiments

Abstract

Cu is widely used to fabricate highly efficient conductive coatings in the power electronics industry due to its exceptional electrical and ductility. To achieve higher spraying speed and better Cu coating quality, this article deeply studied the method of accelerated plasma spraying (APS) based on electromagnetic pulse welding (EMPW). A multiphysical field simulation model was constructed to study the plasma and Cu powder motion processes. The electromagnetic parameters, temperature, and Cu powder velocity were obtained. The relationship between electrode parameters and the Lorentz force was obtained by combining the plasma equation of motion with numerical analysis. The velocity of the Cu powder motion was obtained through the capture of the spraying process. The findings revealed that the electrode spacing exerted an influence on the plasma motion. The simultaneous impact of the compression shock wave and the Lorentz force propelled the Cu powder, which remained in the solid state, toward the ceramic. The Cu powder speed reached 1024 m/s and the maximum Cu coating thickness of $140~\mu $ m was obtained when the discharge voltage was 5 kV. This study elucidated the mechanism of APS based on EMPW, thereby providing a theoretical foundation for APS in mechanism analysis and future applications.