Quenched-in vacancies in Fe3Al based alloys: A positron annihilation study

Abstract

In the present contribution, high-resolution positron lifetime spectroscopy and slow positron implantation spectroscopy are used to characterize defects in Fe75.99Al24.01 and Fe71.98Al28.02 alloys. In order to facilitate defect identification, we also perform a theoretical study of basic vacancy-like defects in three phases of the Fe 3Al system: ordered (D03), short-range ordered (B2) and disordered (A2). Positron characteristics, i.e. positron lifetime and positron binding energy to defects are calculated from the first principles for various defect configurations. The results are discussed in the context of experimental data obtained here and available in literature. © Published under licence by IOP Publishing Ltd.