A model of growth of an intermediate phase in bi- and polycrystals

An analytically solvable model of the growth of an intermediate phase between low-soluble components on diffusion at grain boundaries involving outflow is suggested. Criteria for a transition from the Fisher regime t1/4 to a parabolic one are established. The formalism suggested is extended to the case of the growth of a solid-state solution with an exponential concentration dependence of the diffusion coefficient.