A method for constructing equilibrium phase diagrams of substitutional nanocrystalline binary alloys is proposed. Fundamental mathematical models for such diagrams are presented. It is shown that the severe plastic deformation (SPD) of multiphase alloys can lead to the complete dissolution of secondary phases. In these cases, SPD most probably results in the formation of equilibrium, chemically heterogeneous, single-phase solid solutions with varying degrees of impurity atom saturation. The chemical heterogeneity within the single-phase states of these nanocrystalline alloys is attributed to the segregation of impurity elements at the intercrystalline boundaries of nanocrystallites.
Vasil'ev et al. (Wed,) studied this question.