An Experimental Study on Deposition Mechanism of High-Speed Spraying Cu Coating Based on Electromagnetic Pulse Welding Technology

Cu is often used in the field of surface engineering to prepare conductive and thermal conductive coatings due to its excellent conductivity, thermal conductivity, and ductility. In order to improve the quality of the coating and achieve higher spraying speed, this article conducts experiments to verify the feasibility of high-speed spraying Cu coatings based on the electromagnetic pulse welding technology and captures the powder movement process of spraying to obtain the powder movement speed. The microscopic process and diffusion of Cu particles colliding and depositing on the substrate were studied by constructing a molecular dynamics simulation model, and the morphological changes of particles and substrate were obtained. Then, drawing root mean square displacement curves and radial distribution functions to study the diffusion process of atoms and the formation process of amorphous structures, and the microscopic morphology of the experimental samples was observed, revealing that the combination between the powder and the plate was good. The cross section formed a wave interface similar to electromagnetic pulse welding, which could achieve mechanical occlusal connection. At the voltage of 5 and 7 kV, 1.5-and 4- <tex-math notation="LaTeX">μ</tex-math> m diffusion zones could be formed. As the voltage increased, the diffusion thickness increased, which was beneficial for coating bonding.