STRUCTURAL AND ELASTIC PROPERTIES OF AgNi10 ALLOY STUDIED WITH AB-INITIO CALCULATIONS

Abstract

First-principles calculations based on density functional theory (DFT) are used to calculate the structural, elastic and thermodynamic properties of the supersaturated solid-solution AgNi10 alloy, applied mainly to electrical contact materials. In this work, for the exchange-correlation energy, the generalized gradient approximation (GGA) functional is used. The calculated structural and electronic properties of supersaturated solid-solution AgNi10 alloys show that the occupation of Ni in the Ag lattice is ordered. All single-crystal elastic stiffness constants of the energetically and mechanically optimized stable AgNi10 model are calculated using the finite strain method and using the Voigt-Reuss-Hill approximation. Various anisotropic indices like the universal anisotropic index, shear anisotropic index, directional dependence of Young’s modulus, bulk modulus and others are calculated to study the elastic anisotropy. The strong anisotropy in the elastic properties of AgNi10 was confirmed. Phonon dispersions were carried out, showing that the AgNi10 crystal has dynamic stability. The Debye temperature is calculated from the elastic data by estimating the average sound velocity in the AgNi10. Furthermore, the vibrational thermodynamic properties (free energy, enthalpy, entropy and heat capacity) of AgNi10 are obtained successfully.

Effect of Nb Doping on the Electrical Contact Properties of AgNi Contact Materials

“…The interfacial work of separation (W sep ) refers to the reversible work per unit area required to separate a two-phase interface into two free surfaces. This measurement is used to evaluate the interfacial bonding strength [19]. When the interfacial separation work is positive, it indicates that the two interfaces can form a stable interface.…”