Site preference and effect of alloying on elastic properties of ternary<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>B</mml:mi></mml:math>2 NiAl-based alloys

Abstract

Using the exact muffin-tin orbitals method in conjunction with the coherent potential approximation, we study the site preference of transition metal impurities X ($\mathrm{X}=\mathrm{Sc}$, Ti, V, Cr, W, Re, Co) in $B$2 NiAl and their effect on its elastic properties. Analyzing interatomic bonding of NiAl-X alloys and elastic characteristics evaluated from the elastic constants ${C}_{11}$, ${C}_{12}$, and ${C}_{44}$, we predict that the addition of W, V, Ti, and Re atoms could yield improved ductility for $B$2 NiAl-X alloys without significant changes in the macroscopic elastic moduli.