The thermal conductivity of the Mg-1Mn-2Zn-xNd alloys (x = 0.5, 1.0, 1.5 wt. %) was studied for the potential applications of heat dissipation. The phase constituents were examined by X-ray diffraction analysis, and the microstructure was observed by light and scanning electron microscopes. The thermal conductivity of the Mg alloys was gauged at room temperature using laser flash method. The experimental results indicate that the thermal conductivity of both the cast and extruded Mg alloys decreases slowly with Nd content, and the extrusion process remarkably reduces the grain sizes and thermal conductivity of the Mg alloys. The thermal conductivity of cast Mg-1Mn-2Zn-xNd alloys exceeds the required critical value (100 W/(m·k)) for the cast Mg alloys. Among them, the cast Mg-1Mn-2Zn-1Nd alloy has great potential to be a good candidate of heat dissipation materials due to its good combination of thermal and mechanical properties.

To evaluate the potential values in heat dissipation applications, this study investigated the microstructure, mechanical and thermal properties of the Mg-0.5Ca-xZr alloys (x = 0.5 and 1 wt.%) under the as-cast, as-extruded and aged states. The phase constituents of the Mg alloys were examined by X-ray diffraction analysis, and the microstructure was inspected by optical microscopy and scanning electron microscopy. The thermal conductivity and mechanical properties of the Mg alloys were measured by the laser flash method and tensile tests, respectively. The results showed that the Mg alloys exhibited the equiaxed microstructure which is composed of α-Mg, Zr and compound Mg₂Ca. Both the extrusion process and increase of Zr content remarkably enhanced the mechanical strength of the Mg alloys and deteriorated the thermal performance simultaneously. It was also found that the thermal conductivity and mechanical strength of the Mg alloys increased gradually with the increase of aging time due to the higher precipitation of Zr and compound Mg₂Ca during the aging treatment. TheMg-0.5Ca-0.5Zr alloy aged at 473 K for 48 h demonstratedhigher thermal conductivity than the required values of the Mg alloys used as heat dissipation materials. Moreover, theMg-0.5Ca-0.5Zr alloy exhibited similar mechanical strength to the commonly-used Mg alloys, highlighting its potential become a potential heat dissipation material in the future due to its good combination of high thermal performance and mechanical strength.

Mg-1Mn-2Zn-1Nd alloy (mass %) has been developed for use as a hard tissue implant material. As-cast Mg-1Mn-2Zn-1Nd alloy exhibited a good biocompatibility and mechanical properties. To improve the corrosion performance and mechanical strength of the Mg-1Mn-2Zn-1Nd alloy, the hot extrusion was applied on this alloy. The influence of extrusion process on the microstructure, mechanical properties and in vitro corrosion performance of Mg-1Mn-2Zn-1Nd alloy has been investigated by X-ray diffraction analysis, optical microscopy, scanning electron microscopy, uniaxial tensile and compressive tests, electrochemical and immersion measurement. The experimental results show that the extrusion can significantly refine the microstructure of Mg-1Mn-2Zn-1Nd alloy, resulting in the improvement of mechanical properties and corrosion performance. The extrusion process does not alter the corrosion mechanism of a Mg alloy.