First-principle calculations on the Al/L12-Al3Zr heterogeneous nucleation interface

Abstract

The interfacial properties including interfacial energy, work of adhesion and electronic structure of Al(100)/Al3Zr(100) were calculated by first-principle calculations based on the density functional theory. The seven layered Al(100) slab and nine layered Al3Zr(100) slab were employed to construct the interface models. And six Al(100)/Al3Zr(100) interfaces, including Top, Bridge and Center sites for the Al- and AlZr- terminations, were considered to study. The interfaces with center site stacking of both terminations are the most stable as they have the largest adhesion work (Wad). The interfacial bonding characteristics is a combination of covalent and metallic bond for the AlZr-terminated center site interface, but only metallic for the Al-terminated center one. Under the whole range of μZrslab−μZrbulk, the interfacial energy of AlZr-terminated center interface is negative, which is much smaller than that of α-Al and its melt (0.15J/m2), indicating that Al3Zr particle is an effective nucleant for α-Al primary grains.