Ab initio investigations of the interfacial bond of Fe(001)/Al(001)

Density functional theory-based ab initio simulations were performed to investigate the bond strength of an Fe (001)/Al(001) coherent interface, its atomic configuration, oxidation at the interface, and mechanical deformation along the lateral direction of the interface. The bcc-type interface exhibited the highest bond strength in terms of the work of separation, but the bond strength decreased significantly when oxygen was introduced. The fracture of the bare interface initiated at the Al matrix under tensile loading, whereas that of the oxidized interface began at the interface because oxygen deteriorated the high bond strength between the Fe and Al atoms. Additionally, the bond strength of the interface was investigated under different biaxial strains to understand the effect of the residual stress generated during the joining process of Fe(001)/Al(001). Based on our findings, the mechanical deformation along the lateral direction does not significantly impact the bond strength