Investigation of silicon sublattice substitution within (Al,Si)₃Zr intermetallics via DFT simulations

Abstract Aluminum alloys commonly contain Si as an impurity or alloying element. The energetic behavior of within multiple compounds and solutions is incorporated inside thermochemical packages, such FactSage. This tool allows determining the partitioning complex multiphasic systems. Recent experimental research suggests that can be found Al 3 Zr-based intermetallics. Nevertheless, current FactSage databases do not consider potential substitution Zr-D0 23 solid solution. In this work, (Al,Si) phase was investigated by means first-principles calculations. Replacement atoms resulted in a negative enthalpy mixing, indicating energetically enabled. density states (DOS) for both Si-diluted Zr non-Si-doped (Al Zr) simulation cells were analyzed. It shown (even dilution), significantly impacts electronic structure structure. Specifically, presence localizes electrons p orbital Al, increases DOS d xy , xz yz sub-orbitals at low energies. Thus, yielding coupled effect stabilizes D0 intermetallic. These findings are benchmark future integration Si-based end-member solution databases.