Anisotropy and oxygen activity dependency of the liquid or solid metal-oxide interfacial free energy: Case study on MgO-Cu

The present study of the equilibrium shape of liquid or solid metal inclusions in oxides or oxide inclusions in solid metals presents a novel approach for the study of anisotropy and oxygen partial pressure dependency of metal-oxide free specific interfacial energies. In the case of solid-liquid or incoherent or nearly incoherent solid-solid interfaces the precipitate equilibrium shape is determined by the anisotropy of the interfacial free energy. Precipitate shapes obtained at different experimental conditions can then be explored with help of the Wulff's construction in terms of relative interfacial free energies. In the present work relative values have been obtained in the MgO-Cu system for solid and liquid precipitates under different oxygen activities.