The energies of intrinsic and substitutional point defects in L10 TiAl were calculated within a first-principles local density functional framework. Relaxed structures and energies for vacancies, antisites and solid solutions were calculated by using a plane-wave pseudopotential method. The calculated defect energies were used, within a canonical ensemble formalism, in order to estimate the point-defect densities as a function of temperature and composition. The density of vacancies was found to be sensitive to the underlying stoichiometry of the TiAl.

Density of Thermal Vacancies in γ-Ti-Al-M, M = Si, Cr, Nb, Mo, Ta or W. C.Woodward, S.Kajihara: Acta Materialia, 1999, 47[14], 3793-8