Fabrication and Thermoelectric Properties of Al/Mg₂Si Composite Materials

Abstract

Mg₂Si has attracted interest as a potential thermoelectric material that can convert waste heat into electricity. To improve thermoelectric performance of Mg₂Si, Al/Mg₂Si composite materials with nominal composition of xAl/Mg₂Si (x = 0.25, 0.5, 0.75, 1.0, or 1.5) were fabricated, i.e., an Al metal phase was introduced to an Mg₂Si matrix. Reflecting an increase in the electrical conductivity and a decrease in the Seebeck coefficient with increasing x, the power factor was successfully enhanced by the incorporation of the Al phase. The increase in electrical conductivity was discussed in terms of electron carrier density and carrier mobility.