In this work, the first-principles method based on density functional theory was used to study the elastic and thermodynamic properties of W-Re binary alloys with different compositions. According to the special quasi-random model, the disordered solid solution model of solid solution alloys was constructed and its lattice structure was optimized. The results showed that, the value of enthalpy and binding energy was increasing, and the solid solution was more difficult to form, the stability of solid solution was worse as the concentration of Re atoms in the solid solution increasing. The electronic level density was used to explain its stability. Then, the stress-strain method was used to calculate the independent elastic constant of the optimized structure. It was verified that the solid solutions constructed satisfy the mechanical stability criterion in this work. The mechanical constants of the solid solution were calculated according to the V-R-H (Voigt-Reuss-Hill) approximation, and the results showed that the bulk modulus of the solid solution increased, and the shear modulus and Young's modulus decreased with the increase of the concentration of Re. Each solid solution showed toughness, according to the brittleness and toughness criterion, the toughness of the solid solution was increased by increasing the concentration of Re atoms. Finally, based on the quasi-harmonic approximation, the phonon spectra and the corresponding phonon densities of states of alloys with different composition were calculated.There was a large number of virtual frequencies in the W12Re4 phonon spectrum, which indicates that the structure is unstable. The calculation and research in this work can provide some references for the relevant experimental research and practical production of W-Re alloys. © 2019, Materials Review Magazine. All right reserved.
