Stress-induced destabilization of solidification and melting fronts

The morphological evolution of the initially planar solidification and melting fronts of a thin liquid film in a stressed binary alloy has been investigated when diffusion only proceeds in the liquid phase. A linear stability analysis has been performed and the diffusion-controlled evolution of the shape of both fronts has been characterized. The destabilizing effect of stress on the profiles of the interfaces has been identified for a liquid film at rest when the solid is submitted to constant stress and when it is migrating, due to stress gradient, in the hypothesis where concentration field of solute satisfy Laplace’s equation. The possibility of roughness formation in the early beginning of the development of the solid–liquid interfaces has been finally discussed for alloys in the context of a liquid film migration mechanism.