A connection was demonstrated between the free energy, diffusion and solute segregation of interfaces by assuming that the interface free energy was the difference between the energy for diffusion in the lattice and in the interface. It was known that the interface energy decreased upon adding solutes. Investigations of pure polycrystalline metals yielded grain boundary energies which were comparable to directly measured ones. The role which was played, by solute segregation at grain boundaries, in altering diffusion was considered. Solute segregation parameters (enthalpy and entropy of binding) were extracted, and the levels of solute concentration were estimated. It was shown that similar analyses, when applied to complex materials such as the Pb-Sn eutectic, also resulted in acceptable values of the interface energies and segregation factors.

Diffusion, Solute Segregations and Interfacial Energies in Some Materials - an Overview. D.Gupta: Interface Science, 2003, 11[1], 7-20