First-Principles Calculation of Interaction Energies between Solutes and/or Vacancies for Predicting Atomistic Behaviors of Microalloying Elements in Aluminum Alloys

Abstract

The atomistic behaviors of microalloying elements during phase decomposition of Al- Cu-Mg, Al-Zn-Mg and Al-Mg-Si alloys have been systematically predicted in terms of two-body interaction energies between solutes and/or vacancies. The utilized first-principles calculation based on generalized gradient approximation (GGA) and full-potential Korringa-Kohn-Rostoker (FPKKR) Green’s function method accurately estimated such fundamental energies in good agreement with experimentally reported behaviors: e.g. vacancy-trapping model, vacancy-sink model and nanocluster assist processing. The proposed interaction energy maps (IE maps), in which the estimated interaction energies are plotted along the rows of the periodic table, are quite useful for designing new aluminum alloys with microalloying elements.