Thermal conductivity of the Mg–Al–Zn alloys: Experimental measurement and CALPHAD modeling

Abstract

Thermal conductivity in a series of annealed Mg–Zn, Al–Zn and Mg–Al binary alloys was studied by experimental investigation and CALPHAD (CALculation of PHAse Diagram) methodology. Microstructure and phase identification of the alloys were determined using scanning electron microscopy and X-ray diffraction techniques. Thermal conductivity was measured over the temperature ranges from 298 K to 498 K on a Netzsch LFA457 using laser flash method. Based on the obtained experimental data, the mechanism of thermal conductivity variation was proposed. Considering the available experimental data from literature and the present work, the thermal conductivities of the Mg–Al–Zn system including pure elements, intermetallics, solid solution phases and two-phase regions were evaluated using the CALPHAD method (CALculation of PHAse Diagram). A set of self-consistent parameters for description of the thermal conductivity in Mg–Al–Zn system was obtained. The calculated results using the obtained parameters and the available experiment data shows an excellent consistency.