ON THE THEORY OF HOMOGENEOUS NUCLEATION OF INCOHERENT INCLUSIONS IN SOLID SOLUTIONS

Based on a critical analysis of the traditional theory of homogeneous nucleation of incoherent precipitates of a new phase in solid solutions, it is shown that the elastic energy associated with a difference in the atomic volumes of two phases does not contribute to the nucleation barrier due to the absorption of thermal point defects at the particle-matrix interface (in contrast to the traditional approach). Correspondingly, a new kinetic model is developed for the rate of nucleation of incoherent precipitates in a supersaturated solid solution of alloying atoms, which has also been generalized to take into account excess vacancies formed under non-equilibrium conditions of quenching tests.