Insight on the Electronic, Elastic and Thermal Properties of Au-Al Intermetallic Compounds Based on First-Principles Calculations

This study investigates the structural stability, electronic structure, and elastic and thermodynamic properties of Au-Al intermetallic compounds (IMCs) using first-principles calculations based on density functional theory, and further discusses their hardness and toughness values. AuAl2, AuAl, Au2Al, Au8Al3 and Au4Al are all phases of the Au-Al alloy. The calculated cohesive energy and enthalpy of formation show that AuAl2 has the best phase stability. Analysis of the electronic structure of each phase shows that the covalent bond characteristics weaken with the increase in Au content, among which Au4Al has the weakest covalent bond characteristics and the lowest hardness value. In addition, the Debye temperature and thermal conductivity of each phase are analyzed. [GRAPHICS] .