Irradiation effects in H and He implanted B2 iron aluminide

Abstract

In order to study the irradiation effect of hydrogen and helium implantation, B2-FeAl alloys were exposed to hydrogen and helium beams with energy of 250 and 540 keV under doses ranging from 1 × 1016 to 1 × 1017 ions cm−2. The phase and surface morphology of FeAl alloy before and after implantation were characterized by X-ray diffraction and scanning electron microscope, respectively. The structure disorder induced by ion implantation was found, and irradiated damage appeared as large amount of dark zone only for high fluence of implantation. Using transmission electron microscopy, the microstructure and implantation structure defects such as gas bubbles and voids were investigated in high dose implanted FeAl. The formation process of bubbles and voids can be deduced by the analysis of TEM images, and the growth of the voids might be promoted by the synergistic effect of H and He implantation. It was speculated that the synergistic effect of tritium and helium might also be found in occasions of tritium irradiation.