Diffusion-limited crystallization of heterogeneous glasses

Based on the classical Kolmogorov-Johnson-Mehl-Avrami theory a model of crystallization of amorphous solids subject to their real structure is developed. Owing to the heterogeneous structure of multicomponent amorphous alloys there are several possible scenarios of crystallization kinetics. Heterogeneous nucleation and growths kinetics of crystallites are considered, taking into account bulk diffusion, enhanced diffusion on internal surfaces and depletion of diffusing components. The analytical solutions obtained are in nice agreement with recent experimental data. The impact of the crystallization on the metallic glass hardening is considered within the development of the approach. A first draft of a theoretical description of this phenomenon is also given.