A note on the contact conditions at migrating interfaces

In addition to mass conservation and energy balance relations, conditions at the migrating interface ("contact conditions") are required to predict the values of the variables at a sharp interface. In this paper frequently used contact conditions are discussed with respect to their inherent presuppositions, and a thick interface with zero internal fluxes is investigated. The contact conditions are automatically related to an off-equilibrium situation in the case of a finite interface mobility and can be derived from the principle of maximum Gibbs energy dissipation. The transformation kinetics for a deviation from local equilibrium has recently been studied by utilizing schematic Gibbs energy diagrams. The numerical results obtained in the present work confirm the predictive character of these schematic diagrams. (c) 2007 Acta Materialia, Inc. Published by Elsevier Ltd. All rights reserved.