Structural and mechanical properties of homogeneous solid-liquid interface of Al modelled with COMB3 potential

In this study, the homogeneous (1 0 0), (1 1 0) and (1 1 1) interface between solid Al and liquid Al are examined using a recently developed third generation of charge-optimized many body (COMB3) potential and molecular-dynamics simulation (MD). The estimated melting point is about 22% higher than the experimental value, but the reproduced radial distribution function of liquid Al agrees pretty well with experimental result. The interfacial widths (δ) of the (1 0 0), (1 1 0) and (1 1 1) interface derived from smoothed density profiles are about 4, 6 and 4 crystal layers, respectively. The stress profiles are highly orientation dependent and the magnitudes of the stress peaks near the homogeneous interfaces are weaker than those near heterogeneous interfaces. Excess interfacial stress and excess interfacial potential energy are also obtained. The information about the homogeneous interfaces obtained in this study can enrich the understanding of homogeneous solid-liquid interface and will serve as a useful reference for future studies of Al-ceramic interfaces using COMB3 potentials.