Complete mapping of the anisotropic free energy of the crystal-melt interface in Al

Abstract

We have calculated the complete anisotropic crystal-melt interfacial free energy of aluminum, using molecular dynamics simulations of the interfaces in equilibrium. The interfacial free energy, $\ensuremath{\gamma}(\mathbf{n}^),$ can be expressed in terms of two anisotropic parameters, $\ensuremath{\epsilon}=1.2$% and $\ensuremath{\delta}=\ensuremath{-}1.2%,$ as well as an average free energy of ${\ensuremath{\gamma}}_{0}=149{\mathrm{m}\mathrm{J}/\mathrm{m}}^{2}$ in reasonable agreement with current experimental results. The expansion of the free energy in terms of these parameters is consistent with six different orientations, including the (111) interfacial plane, which is found to be rough despite its large stiffness.