The concentration of site vacancies was analyzed as a function of the concentration of interstitial non-metallic atoms in cubic metal crystals. An increasing dependence was established. The site-vacancy concentration could exceed the concentration of thermally activated vacancies in a pure face-centered cubic metal at a given temperature, and over a wide range of interstitial concentrations. The factors which promoted the formation of such interstitial-induced site vacancies included a strong repulsion between interstitial non-metallic atoms and site metal cations, and a sufficient solubility of interstitial atoms (or clustering that led to their local accumulation in interstices). On the other hand, an applied pressure decreased the content of impurity-induced site vacancies. A monotonically increasing dependence was established for the site vacancy concentration as a function of the H concentration in face-centered cubic Fe. The γ*-phase of H-containing face-centered cubic Fe was expected to be enriched with vacancies at high H-doping levels.

Impurity-Induced Host-Lattice Vacancies in Metals and Interstitial Alloys. V.M.Bugaev, V.A.Tatarenko, C.L.Tsynman, B.Z.Yanchitskii, I.M.Maksimchuk, V.G.Tkachenko: International Journal of Hydrogen Energy, 1999, 24[2-3], 135-40