The Effect of Alloying Elements on the c/a Ratio of Magnesium Binary Alloys

In order to clarify the effect of alloying elements on the axial ratio of magnesium binary solid solutions, the solid solutions of Mg-Al, Mg-Zn, and Mg-Li with various concentrations were casted and homogenized. Synchrotron X-ray diffraction patterns were then obtained from annealed powder samples and analyzed using the Rietveld method. The effects of solutes concentration on lattice parameters were explained on the basis of atomic size difference and valence electron effect, which changes electron overlap of magnesium. It has been found in this study that Al and Li raise and reduce the c/a ratio, respectively, while Zn has no effect on the c/a ratio.