The effect of alloying elements on the structural stability, and mechanical and electronic properties of Al3Sc: A first-principles study

Abstract

The first-principles methods, based on the density function theory, are performed to calculate the properties of pure and doped Al3Sc. The structural stability, and mechanical and electronic properties of L12-Al3Sc1-xMx (M = Zr, Ti, Y, and Li) have been investigated. A negative formation enthalpy for L12-Al3Sc1-xMx indicated that all doped structures were stable, and Al24Sc6Zr2 was found to be the most stable. The elastic constants, elastic moduli and Debye temperatures of Al3Sc, with different doping elements and different doping concentrations, were calculated to explore the influences of doping on the mechanical properties and Debye temperatures of Al3Sc. Furthermore, the calculated results suggested that both Al24Sc6Zr2 and Al24Sc6Ti2 could optimize the mechanical properties. Finally, the electronic properties based on the analyses of densities of states and electron density distributions, have been performed, to explain the underlying mechanisms for the structural and mechanical properties of the L12-Al3Sc1-xMx structures.