Prediction of multi-phase equilibria in alloy systems by the technique of successive partial equilibration

Abstract

The technique of successive partial equilibria was recently employed to predict the precipitation of carbides in equilibrium with a solution phase. This involved predicting the equilibrium between a phase (the solution) whose composition could change with the overall composition of the system, and a phase which had a fixed stoichiometry with respect to the ratio of the number of atoms in the cationic sub-lattice to that in the anionic sub-lattice. This is a special case of predicting phase equilibria using this technique. In the present communication, this technique is extended to predict equilibria involving two or more phases whose compositions can vary over a range, such as that between two solutions phases. This technique is illustrated with respect to the Ag-Cu system and some salient features of the algorithm are discussed.