Enhancement of ductility in cubic Rh₃A_xTi_1−x(A = V,Nb,Ta)(x = 0, 0.125, 0.25, 0.75, 0.875, 1) aerospace materials–First principles DFT study

Structural, electronic, elastic and mechanical properties of cubic Rh₃A_xTi_1−x (where A = V, Nb, Ta and x = 0, 0.125, 0.25, 0.75, 0.875, 1) alloys are investigated by FP-LAPW method using the Density Functional Theory (DFT) within the generalized gradient approximation (GGA). The ground state properties of these compounds have been obtained by the optimization procedure as implemented in the wien2k code. The electronic and bonding patterns of the same are analysed. Using the calculated elastic constants, the Shear modulus, Young's modulus, Poisson's ratio, Pugh criteria, Cauchy's pressure and Hardness values are derived. The ductility of these refractory alloys are analysed in terms of Cauchy's pressure, Pugh criteria and Poisson's ratio. The results are further assessed by using the charge density plots. From this study, we conclude that, among Rh₃A_xTi_1−x (A = V, Nb, Ta; x = 0, 0.125, 0.25, 0.75, 0.875, 1) alloy combinations, the Rh₃Nb_0.75Ti_0.25 alloy is found to be more ductile and yet another combination namely Rh₃Nb_0.875Ti_0.125 could serve as a preferred ductile material with a reasonable hardness. - Highlights: • The elastic and mechanical properties of Rh₃(V,Nb,Ta)_xTi_1−x alloys are investigated. • Ductility of these materials are analysed using (C₁₂–C₄₄), G/B ratio and ν values. • The results are assessed by charge density plot. • Rh₃Nb_0.75Ti_0.25 and Rh₃Nb_0.875Ti_0.125 alloys are found to be more ductile.