Elastic and thermodynamical properties of A15 Nb3X (X = Al, Ga, In, Sn and Sb) compounds - First principles DFT study

Elastic and thermodynamical properties of Nb3X (X = Al, Ga. In, Sn and Sb) compounds are obtained by performing the band structure calculations, using the FP-LAPW method. The calculated lattice constants, elastic constants, Bulk modulus, shear modulus, Young's modulus, Poisson's ratio, Debye temperature and anisotropy ratio are reported and the results agree with the available data. From the present study, it is observed that stiffness and shear resistance are found to be greater in Nb3Sb than in other compounds. It is more brittle in nature and comparatively harder than other materials under study. The degree of anisotropy decreases as one moves across Nb3Ga, Nb3Al, Nb3In, Nb3Sb and Nb3Sn. From the calculated values of the Debye temperature, it is observed that thermal conductivity is greater for Nb3Sb and less for Nb3In. (c) 2010 Elsevier Ltd. All rights reserved.