Atomistic simulation into Cu-Al explosive welding joint formation mechanisms and deformation characteristics

Abstract

This study investigates the formation mechanisms and deformation behaviors of Cu-Al explosive welding joints using molecular dynamics (MD) simulation. The study evaluates the effects of impact speed, impact depth, impact angle, and ultrasonic vibration on the deformation behaviors and dislocation distributions of the Cu-Al explosive weld joint. During the tensile test process, the stress distribution can be classified into three zones: the low-stress zone of the Al plate, the high-stress zone of the weld joint, and the medium-stress zone of the Cu plate. Weld joint strength can be considerably increased by modifying the impact angle and applying vibration-assisted movement. It is noteworthy that strain, stress, dislocation density, crystalline structure, and UTS value are all increased by vibration during the explosive welding process due to the improvement of strain-hardening and diffusion mechanisms. The diffusion mechanism in explosive welding refers to the rapid diffusion of molten metals under high pressure.