Effects of elastic stress on the stability of a solid-liquid interface

The effects of elastic stress on the stability of solid-liquid interfaces under avariety of conditions are discussed. In the cases discussed, the nonuniform compositionfield in the solid, which accompanies either the melting process or thedevelopment of a perturbation on the solid-liquid interface during solidification, generates nonhydrostatic stresses in the solid. Such compositionally generatedelastic stresses have been shown experimentally to induce a solidifying solid-liquidinterface to become unstable. We are in the process of analyzing the effects ofthese stresses on the conditions for morphological stability of a directionally solidifiedbinary alloy.