Diffusion characteristics of Cu/Al/Cu interface based on molecular dynamics

Based on molecular dynamics simulation, the interfacial diffusion process of the Cu /Al /Cu system is simulated. The diffusion characteristics and evolution law of interfacial atoms are analyzed using mean square displacement, diffusion coefficient, radial distribution function, and atomic concentration distribution. The results show that the Cu atomic energy is deeply diffused into Al, while the Al atom is only diffused to the Cu side, and the diffusion range is limited to the interface. With the increase in temperature, the thickness of the interfacial transition layer increases and expands to both sides gradually. At the Cu /Al /Cu interface, the ordered structure of Al is destroyed in the diffusion process, showing disorder. At the same time, the Cu layer as a whole maintains a high order, only the structure near the interface is slightly disordered. At the same time, three diffusion mechanisms of Cu atoms in the Al lattice have been found, and the main diffusion mechanism is the first neighbor transition.