An atomistic study of solid/liquid interfaces and phase equilibrium in binary systems

A semiempirical Lennard-Jones/Embedded Atom Method model is used to capture real materials' behavior through the introduction of many-body forces. By means of molecular dynamics (MD) calculations, the model is used to study the dependence of the solid/liquid interface velocity on temperature and composition. Based on the MD results, the free energies and the chemical potentials in the solid and liquid phases are calculated to produce the phase diagrams. These calculations illustrate the consequences of differences in energy and size between the components on the phase diagrams. An asymmetry in velocity between solidification and melting is found. Slowing of the interface velocity by solutes during solidification is demonstrated.