Grain boundary energy function for fcc metals

Anisotropy of interfacial energy is the principal driving force for thermally driven microstructure evolution, yet its origins remain uncertain and a quantitative description lacking. We present and justify a concise hypothesis on the topography of the functional space of interface energies and, based on this hypothesis, construct a closed-form function that quantitatively describes energy variations in the 5-space of macroscopic parameters defining grain boundary geometry. The new function is found to be universal for the crystallography class of face-centered cubic (fcc) metals.