A general thermodynamic description was developed for such interfaces. This was very different to descriptions that were based upon classical non-equilibrium thermodynamics, in that a linear relationship between fluxes and forces was not assumed. It was also not limited to small departures from equilibrium. Moreover, allowance was made for diffusion in the bulk and the composition of material transferred across the interface could differ from the composition of either phase. Solute drag was included as a special case, and heat flow in both phases could be included. Linearized interface conditions were developed for treating the evolving interface.

M.E.Gurtin, P.W.Voorhees: Acta Materialia, 1996, 44[1], 235-47