First-principle study of adhesion, wetting and bonding on Al/Al3V(001) interface

The adhesion, wetting, and bonding on fcc-Al(001)/D022-Al3V(001) interface were investigated using density functional calculations. Considering different terminations of Al3V(001) (Al- and Al + V-terminated) and stacking sites (center-, hollow- and top-sites), six Al/Al3V(001) models were calculated. For the models with same stacking site, Al + V-terminated model has larger work of adhesion (Wad) than the Al-terminated one. For the models with same termination, the work of adhesion decreases, and the interface energy (γint) increases as the order of top-, bridge- and center-sites. Al-terminated-center-sited and Al + V-terminated-center-sited models are more stable among six models. After complete structure relaxation, both models have the same epitaxial stacking style. Therefore, the both models can be regarded as of the same and most stable one (noted as CSI model), but separating along Al-Al and Al-Al+V inter-planes. Based on the perfect wetting and strong adhesion in CSI model, the heterogeneous nucleation of α-Al on Al3V(001) was interpreted in terms of crystallography and thermodynamics. The interfacial bonding was discussed with analysis of valence electron density distribution and partial density of states (PDOS). The bonding is mainly contributed from AlV covalent bonds and AlAl metallic interactions.