Effects of Nd/Gd value on the microstructures and mechanical properties of Mg-Gd-Y-Nd-Zr alloys

Four Mg-Gd-Y-Nd-Zr alloys were prepared by mold casting to investigate the effects of Nd/Gd ratios on microstructures and mechanical properties. The as-cast alloys mainly consist of alpha-Mg and beta-Mg5(GdYNd). Volume fractions of the second phase increase and grains were slightly refined with the rising Nd/Gd ratio, when the alloying addition is equal. Meanwhile, fibers of second phase also increase in the extruded alloys when the Nd/Gd value increases. However, the Nd/Gd ratio could hardly influence the mechanical properties of the extruded alloys. The aging hardening response of the extruded alloy differs due to different Nd/Gd ratios. The potential mechanisms have also been discussed in detail. (C) 2016 Production and hosting by Elsevier B.V. on behalf of Chongqing University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).