Abstract
The effect of solid solution alloying elements on the plastic deformation of fine-grained magnesium alloys was studied in four binary alloys; Mg-0.3at.%X (X = Al, Li, Y and Zn), in the strain rate range of 10"2 〜 150 s"1. All the alloys have an average grain size of 2 〜 3 μm, and the solid solution strengthening is observed for all of the alloys through nanoindentation tests. The different alloying elements also have an impact on the rate dependence of deformation, with activation volumes ranging between 20b^3 and 80b^3 (b: Burgers vector) being consistent with cross-slip as a rate-limiting mechanism. The deformed microstructural observations beneath indention show no existence in twinning, which is consisted with the rate-limiting mechanism.
