Comparison about effects of minor Zr, Sr and Ca additions on microstructure and tensile properties of Mg-5Gd-1.2Mn-0.4Sc (wt%) magnesium alloy

► Minor Zr, Sr and Ca additions can refine the grains of the Mg-5Gd-1.2Mn-0.4Sc alloy. ► Minor Zr addition can improve the tensile properties of the Mg-5Gd-1.2Mn-0.4Sc alloy. ► Minor Sr addition can improve the tensile properties of the Mg-5Gd-1.2Mn-0.4Sc alloy. ► Minor Ca addition can improve the tensile properties of the Mg-5Gd-1.2Mn-0.4Sc alloy.