Density of magnesium and magnesium-lithium alloys in solid and liquid states

Abstract New experimental data are presented on the density and thermal expansion of solid and liquid magnesium and ultralight magnesium–lithium alloys containing 23.03 and 30.02 at.% Li, respectively. The measurements were performed using the dilatometer method and the gamma-ray attenuation technique in the temperature range from 145 to 1244 K for magnesium and from 293 to ∼1000 K for the alloys. The density changes during the solid−liquid phase transition were directly measured for Mg and the Mg 70 Li 30 alloy. The temperature dependences and reference tables of the investigated volumetric properties were developed. A comparison of the obtained results with literature data was made. The study showed that the eutectic composition in the magnesium− lithium system differs from 23 at.% Li. The concentration dependence of molar volume of the magnesium−lithium liquid system was found to be almost linear in the interval of 0−30 at.% Li and deviated noticeably from the corresponding dependence for an ideal mixture.