Two-phase systems with dispersed particles of a stable size—I. Theory

Abstract

It is shown that under certain conditions a two-phase system can be thermodynamically stable in a finely dispersed state. This state is characterized by particles of one phase in the matrix of the other phase, whose size is stable and whose number per unit volume can be as large as 10 17. Correspondingly there is no Ostwald ripening of the particles. The conditions are: 1. 1. The existence of a coherent phase boundary on the particle rim, which causes coherence strains because of the different atomic volumes of the phases. 2. 2. The existence of a particle rim zone with a finite thickness D. In this zone the local concentration changes continuously from the value inside the particle to that outside. 3. 3. The ratio of the specific surface energy σ to the product of the specific elastic energy and the rim thickness D does not exceed a certain value.