Electrical transport, thermal transport, and elastic properties of M2AlC (M=Ti, Cr, Nb, and V) -: art. no. 115120

In this paper we report on a systematic investigation, in the 5 to 300 K temperature regime, of the electronic, magnetotransport, thermoelectric, thermal, and elastic properties of four M2AlC phases: Ti2AlC, V2AlC, Cr2AlC, and Nb2AlC. The electrical conductivity, Hall coefficient, and magnetoresistances are analyzed within a two-band framework assuming a temperature-independent charge carrier concentration. As with other MAX-phase materials, these ternaries are nearly compensated, viz. the densities and mobilities of electrons and holes are almost equal. There is little correlation between the Seebeck and Hall coefficients. With Young's and shear moduli in the 270 GPa and 120 GPa range, respectively, the phases studied herein are reasonably stiff. With room temperature thermal conductivities in the 25 W/m K range (45 W/m K for V2AlC) they are also good thermal conductors.