THERMAL CONDUCTIVITY OF MAGNESIUM ALLOYS

摘要

Recently, magnesium alloys have been widely used as lightweight structural materials in manufacturing of automobile, air plane and portable computers. The magnesium alloys have extremely low density and high rigidity. The density of magnesium is as low as 1738 kg/m3, which makes it suitable for such applications as above. In this study, we studied thermal conductivity of two different magnesium alloys made by twin-roll casting with laser flash technique and by differential scanning calorimeter. Thermal diffusivity of the magnesium alloys, AZ31 and AZ61 were measured over temperature ranging from -125 to 400 ℃. AZ 31 and AZ61 are composed of magnesium, aluminum and zinc. Thermal conductivity gradually increased with measurement temperature. Densities of magnesium alloys, AZ31 and AZ61, were 1754 and 1777 kg/m3, respectively. Thermal conductivity of AZ31 alloy was about 25% higher than that of the AZ61 due its dependence on precipitation status.