Investigation of the mg supersaturated solid solution decomposition in the Mg-Dy-Sm alloys
Kinetics and phase transformations during decomposition of the supersaturated Mg solid solution in the Mg-Dy-Sm alloys at different Dy/Sm content ratios were investigated in this work. The solid solution decomposition occurs upon aging at a temperature of 200°C, at which strengthening of the alloys was expected to be highest. With increasing Dy/Sm ratio, the solid solution decomposition gradually decelerates. Addition of Dy to the Mg-Sm alloys intnsifies the age hardening, and the addition of Sm to the Mg-Dy alloys also promotes the hardening. The Mg solid solution decomposition in the ternary Mg-Dy-Sm alloys is accompanied by the formation of the GPzones, ordering, and the precipitation of plate-like particles in certain planes of the Mg crystal lattice. Such processes are typical of solid solution decomposition in the binary Mg-Re (Nd, Sm, Y, Gd, Tb, Dy) alloys.