The structural, elastic, and electronic properties of Zr _x Nb _{1− x} C alloys from first principle calculations

Abstract

The structural, elastic, electronic, and thermodynamic properties of Zr x Nb 1−x C alloys are investigated using the first principles method based on the density functional theory. The results show that the structural properties of Zr x Nb 1−x C alloys vary continuously with the increase of Zr composition. The alloy possesses both the highest shear modulus (215 GPa) and a higher bulk modulus (294 GPa), with a Zr composition of 0.21. Meanwhile, the Zr 0.21 Nb 0.79 C alloy shows metallic conductivity based on the analysis of the density of states. In addition, the thermodynamic stability of the designed alloys is estimated using the calculated enthalpy of mixing.

First-principles study of structural, elastic, and thermodynamic properties of ZrHf alloy

“…where E(V ) is the ground-state total energy at a given unit cell volume V , F vib (T,V ) is the vibrational energy of the lattice ions, and F el (T,V ) is the thermal electronic contribution to the free energy, which can be expressed by electronic entropy S ele (T,V ) and energy due to the electron excitations E ele (T,V ). Under quasi-harmonic approximation (QHA), [17][18][19][20][21] the F vib (T,V ) can be calculated by…”