Ab initio study on the mechanical and electronic properties of the [Ti.sub.1-x][Nb.sub.x]N alloys

The elastic, mechanical and electronic properties of [Ti.sub.1-x][Nb.sub.x]N alloys are systematically studied using ab initio calculations. It is found that the lattice constant of bimetallic nitrides is monotonously increased with Nb concentration, and all the considered compounds are thermodynamically and elastically stable. Present results classify the alloys of [Ti.sub.1-x][Nb.sub.x]N (x = 0, 0.25) as brittle and [Ti.sub.1- x][Nb.sub.x]N (x = 0.5, 0.75, 1) as ductile materials. In addition, the Vickers hardness and Debye temperatures for the [Ti.sub.1-x][Nb.sub.x]N alloys are predicted theoretically.