Devitrification of Heterogeneous Metallic Glasses

The effect of the structure of alloying elements and their solubility in the main component of the alloy on the formation of nanocrystals in the amorphous phase is investigated. The mechanism of the formation of nano crystals based on the similarity of short-range order in ordered regions of a heterogeneous amorphous structure and the structure of the crystallizing phase is considered. It is shown that the presence of structurally related ordered regions provides a large number of potential nucleation sites for nanocrystals and facilitates the process of nano crystallization. Since the fraction of the crystalline phase formed by the primary crystallization reaction is determined by the phase-equilibrium diagram, an increase in the number of such regions leads to the formation of a structure with a smaller nanocrystal size. The parameters of the resulting nanostructure depend on the type of alloying element, its concentration, and also the solubility in the main metal component of the alloy. The results obtained indicate possible implementation of the mechanism of the formation of nanocrystals in ordered regions in the heterogeneous amorphous phase of metallic glasses.