Heavy-ion irradiation of α-iron

Abstract

In this paper we report the results from a transmission electron microscope study of α-iron after irradiation with heavy ions. No visible damage was observed following a low dose of self-ions in the energy range 40–240 keV. This is in contrast to the results from other pure metals where visible damage is produced after self-ion irradiation. Damage, in the form of small vacancy loops, was observed as the incident ion mass was increased, and quantitative results are presented on the dependence of both the defect yield and the defect size distribution on the ion mass. The Burgers vectors of the vacancy loops formed from 80 keV W⁺ ions are analysed and it is shown that both of the possible perfect loop Burgers vectors are present in the foils, i.e. a/2〈111〉 and a〈100〉. Finally, the sensitivity of the defect yield on ion mass and the nucleation of the a〈100〉 loops are discussed.