| مستخلص: |
The electronic and thermodynamic variation of the δ-Ni3Nb phase with pressure in the range of 0–1200 GPa under hydrostatic pressure was investigated by DFT. By comparing the nucleation phase γ with the transition phase γ", it is found that the magnitude of the stability of the three phases remains the same under 0–1200 GPa, and the difference between the stability of δ and γ" phases is small and both are larger than that of γ. This indicates that the δ phase has the precipitation law of γ→δ and γ″→δ under 0–1200 GPa under hydrostatic pressure. The calculated data show that the results obtained by using the GGA-PW91 generalized function have the smallest error with the experimental value, and the properties of energy, cell volume, density of states, differential charge, elastic constant and phonon of γ, γ" and δ phases are calculated after the convergence of each parameter, and the δ phase is a strongly anisotropic material and the most dense vibration at 4.8 and 6.6 THz frequencies and the heat capacity δ>γ ">γ relationship. • Calculated the elastic properties of δ, γ, γ" phase under 0–1200 GPa. • Calculated the electronic properties of δ, γ, γ" phase. • Calculated the phonons and heat capacity of δ, γ" phase at 0 K. • Obtained δ,γ,γ "phase precipitation law. • Calculate the mechanical properties of δ, γ, γ "phase under 0–1200 GPa. [ABSTRACT FROM AUTHOR] |
