Peculiarities of the Eutectic Mg–Li Alloy Thermal Expansion, Heat Capacity and Thermal Conductivity Behavior in the Temperature Range of 80 K to 293 K

Experimental studies of the thermal expansion, heat capacity and thermal conductivity of the eutectic magnesium–lithium alloy (with composition of 23.0 at.% lithium) were performed in the temperature range of 80 K to 400 K. The relative elongation and thermal expansion coefficient of this ultralight magnesium–lithium alloy were measured by the dilatometric method using a DIL-402C setup. Measurements of the heat capacity were carried out by the differential scanning calorimetry using a DSC 404 F1 setup. Investigation of the thermal conductivity was performed by the hot-disk technique using a Hot-Disk TPS 2500S setup. The temperature dependences were constructed and tables of recommended values of the investigated properties were presented. It was found that in Mg 77 Li 23 alloy a phase transition occurs in the range of 223 K to 253 K, where the heat capacity and the linear thermal expansion coefficient change abruptly. This transition is presumably related to the martensitic transformation of the lithium-rich bcc magnesium–lithium alloys to the hcp structure.