Investigation on the Diffusion Behaviors and Mechanical Properties of the Ti/Al Interface Using Molecular Dynamics Simulation

Many studies have been conducted on the preparation of TiAl alloy sheets through Ti foil and Al foil diffusion. Notably, the problem of Ti/Al interface diffusion needs to be solved both theoretically and experimentally. In this paper, molecular dynamics simulation was used to study the diffusion and mechanical properties of the Ti/Al interface. By analyzing the diffusion of titanium and aluminum atoms at different temperatures, the diffusion coefficient of Al atoms in Ti atoms and that of Ti atoms in Al atoms increased with increasing temperature, thus satisfying the Arrhenius formula at the system temperature. The rough interface pre-filled a portion of the pores during the heating stage, causing the pores at the interface to disappear. Therefore, the diffusion effect of the rough interface was more prominent. The values of the diffusion coefficient and the activation energy of the rough interface were not very different from those of the ideal interface. After diffusion, the tensile simulations showed that the strength was approximately 4.2 GPa. Fractures occurred mainly on the Al side during the tensile deformation process, and the ideal interface and the rough interface had different fracture modes during the tensile fracture process.