CHARACTERISTICS OF PHASE-EQUILIBRIA IN COHERENT SOLIDS

Several new results concerning the characteristics of phase equilibria in nonhydrostatically stressed coherent systems are presented for systems in which the deformation of each phase is homogeneous. A critical point is identified, the applicability of Gibbs phase rule relating the number of phases and thermodynamic fields to the degrees of freedom in the system is established, and the existence of a common tangent construction in the appropriate thermodynamic space is proven. The intersection of the hyperplanes and the appropriate free energy of the individual phase in the common tangent construction are shown to form a set of density lines on which all tie lines must end but which need not correspond to the phase boundaries separating single- from two-phase fields. The quantitative results presented herein are in agreement with earlier predictions of phase equilibria in coherent solids. © 1991.