Effect of Ce addition on the microstructure, thermal conductivity and mechanical properties of Mg-0.5Mn alloys

The effect of Ce addition on the microstructure, thermal conductivity and mechanical properties of Mg-0.5Mn alloy was investigated systematically in this study. In addition, the thermal conductivity was measured using flash method in the temperature range of 293-523 K. Results indicate that Ce addition refined the grain structure of both as-cast and as-extruded of Mg-0.5Mn alloys. Moreover, the weakening of texture can be observed by Ce addition. The thermal conductivity of as-cast Mg-0.5Mn-xCe alloys decreased gradually with the increase of Ce content. Meanwhile, the thermal conductivity of as-extruded Mg-0.5Mn-0.3Ce alloy (139.7 W/(m·K)) was higher than that of other as-extruded alloys. Furthermore, the as-extruded Mg-0.5Mn-xCe alloys exhibited higher thermal conductivity than that of as-cast counterparts, except for Mg-0.5Mn-0.6Ce alloy. The weakening of basal texture resulted in the improvement of thermal conductivity of wrought products. The yield strength (YS) and ultimate tensile strength (UTS) of as-extruded Mg-0.5Mn alloys were enhanced by Ce addition. The as-extruded Mg-0.5Mn-0.3Ce alloy showed the best strength and moderate elongation (EL). The UTS, YS and EL of this alloy were 295.9 MPa, 320.9 MPa and 9.6%, respectively.