Ab initio study of the effect of Zr content on elastic and electronic properties of L12–Al3(Sc1−xZrx) alloys

First-principles calculations were performed to investigate the structural, elastic and electronic properties of L12–Al3(Sc1−xZrx) (x = 0.25, 0.5 and 0.75) based on special quasi-random structures (SQSs) with 32 atoms. As the content of Zr atoms increased, the lattice parameters of L12–Al3(Sc1−xZrx) were increased whereas thermodynamical stability was lowered. The obtained C11 and C44 were reduced slightly, indicating that the incompressibility along the principle axes and the resistance to shear in 〈0 0 1〉 direction on the {1 0 0} plane were lowered, the shear and Young’s modulus were also reduced while the bulk modulus were slightly larger. The ductility was improved due to increase of the B/G ratio and Cauchy pressure. The electronic structures revealed that the dominant hybridization between the Al p states and transition-metal d states became weaker with increasing of the content of Zr.