First-principles study of structural, mechanical, and electronic properties of W alloying with Zr**Project supported by the Beijing Municipal Natural Science Foundation, China (Grant No. 2182042) and the National Natural Science Foundation of China (Grant Nos. 11875004, 11505006, and 11604008).

Abstract

The structural, mechanical and electronic properties of W1−xZrx (x = 0.0625, 0.125, 0.1875, 0.25, 0.5) are systematically investigated by means of first-principles calculation. The total-energy calculations demonstrate that the W–Zr binary substitutional solid solution remaining bcc structure can be formed at an atom level. In addition, the derived bulk modulus (B), shear modulus (G), Youngʼs modulus (E) for each of W–Zr alloys decrease gradually with the increase of Zr concentration, suggesting that W alloying with higher Zr concentration becomes softer than pure W metal. Based on the mechanical characteristic B/G ratio, Poissonʼs ratio υ and Cauchy pressure , all W1−xZrx alloys are regarded as ductile materials. The ductility for each of those materials is improved with the increase of Zr concentration. The calculated density of states indicates that the ductility of W1−xZrx is due to the fact that the bonding in the alloy becomes more metallic through increasing the Zr concentration in tungsten. These results provide incontrovertible evidence for the fact that Zr has a significant influence on the properties of W.