First-principles calculation of the effect of V content on the properties of NbMoTaWVx refractory high-entropy alloys

This work focused on the influence of V content on NbMoTaWVx (x = 0.00, 0.25, 0.50, 0.75, 1.00, 1.25, 1.50, 1.75, 2.00) refractory high-entropy alloys (RHEAs). The influence of V content with structure stability, electronic properties, elastic properties, and thermodynamic properties was systematically studied by first-principles calculations and the Gibbs2 program. All alloys prefer to form body centered cubic (BCC) structure according to the minimum energy principle. The electronic properties show that the V element can strengthen the metallicity of NbMoTaWVx RHEAs. The results of elastic properties show that NbMoTaWV0.75 owns the highest ductility and lowest hardness at the same time. Moreover, according to the results of thermodynamic properties, the V element can reinforce the abilities of resistance for thermal softening and thermal expansion at high temperatures. This study can provide guidance for the design and practical preparation of RHEAs.