Density Functional Study of the Aluminum—Graphite Interface

Abstract

Our group has previously performed a series of ab initio calculations to study the atomic structure, ideal work of adhesion, Wad, and bond character of several aluminum—ceramic interfaces. Periodic interfaces were used where the thicknesses of both the Al and ceramic slabs were previously converged with respect to surface energy. Using a plane-wave density functional code with the local density and generalized gradient approximation, our past calculations find the Wad is proportional to the surface energies of the mating materials, and the degree of polarity in the ceramic surface. Our calculations compare favorably with available experimental work of adhesion values of liquid Al on graphite, and Al on Al2O3. We investigated interfacial geometries after atomic relaxation, and interfacial bonding via plots of charge density, charge density difference, the electron localization function, and the projected density of states. In this paper we focus on our preliminary results for the aluminum—graphite interface.