The thermodynamics of hydrogen–vacancy interactions in aluminum Original Research Article

The thermodynamic properties of Al–H solid solutions containing lattice vacancies have been discussed using an approach in which the grand canonical ensemble is used to elucidate the behavior of the Al–VAC–H system in Fermi–Dirac statistics. Calculations have been presented and compared for specific models in which H-atoms act both as a simple interstitial species and forms either decorated vacancies or substitutional defects. Vacancy concentrations concomitant to different levels of hydrogenization are calculated and approximate penetration curves for the ingress of vacancies from the metal surface are presented.