The electronic, mechanical, anisotropic and thermodynamic properties of ZrAlNi, ZrAlNi2, ZrAl5Ni2 and Zr6Al2Ni ternary intermetallics

First-principles techniques were used to determine the mechanical characteristics, electronic structure and thermal characteristics of the ternary intermetallics ZrAlNi, ZrAlNi2, ZrAl5Ni2 and Zr6Al2Ni. The lattice parameters and equilibrium volumes exhibit the concordance with the existing experimental data. Additionally,the formation enthalpies of the four intermetallic compounds are -0.655eV/atom, -0.618eV/atom, -0.409eV/atom and-0.360eV/atom, respectively. Their enthalpy of formation is negative, indicating that they have thermodynamic stability. The elastic constants of all four compounds satisfy the corresponding Bonn stability criteria, indicating that all of them exhibit mechanical stability. The metallic characteristics of the phases are verified according to their density of states and band structure, providing evidence for their ability to conduct electricity. In addition, the band structure and state density map also show that four compounds are not magnetic. Both G/B ratio(0.69) and ν values(0.22) indicate that ZrAl5Ni2 compound studied is brittle materials. The Poisson 's ratios of ZrAlNi, ZrAlNi2 and Zr6Al2Ni are 0.28,0.32 and 0.28,so ZrAlNi, ZrAlNi2 and Zr6Al2Ni exhibit characteristics of ductility materials. Among the four phases, ZrAl5Ni2 has the highest Debye temperature of 216.35 k, indicating its superior thermal conductivity. The Gibbs free energy has a negative correlation with temperature. Among these compounds, ZrAlNi2 has the smallest Gibbs free energy, suggesting its superior formation ability.