To study the helium effects and their interactions with displacement damage in irradiated materials, an in situ dual-ion beam irradiation capability with transmission electron microscopy was recently established at the IVEM-Tandem Facility at Argonne National Laboratory. Pure nickel was irradiated in situ individually with 1 MeV Kr ions for displacement damage study, 16 keV He ions for helium implantation, and simultaneously with 1 MeV Kr ions and 16 keV He ions at the rate of 1 at.% He/dpa to study the interaction of helium and displacement damage at 500 °C. Helium bubbles were formed and segregated within dislocation loops during the He implantation experiment and no bubbles were observed outside the loops. The loop size increased with increasing helium concentration. In contrast, helium bubbles were formed uniformly in the matrix when nickel was irradiated simultaneously with 1 MeV Kr ions and 16 keV He ions. It is suggested that the uniformly-distributed defect clusters formed under 1 MeV Kr ion irradiation serve as trapping sites of helium atoms resulting in homogeneous nucleation of helium bubbles under the dual-ion beam irradiation in nickel.

为了研究辐照材料中的氦效应及其与位移损伤的相互作用，最近在阿贡国家实验室的IVEM-串联实验室建立了具有透射电子显微镜的原位双离子束辐照能力。纯镍被原位照射分别用1 MeV Kr离子进行置换损伤研究，用16 keV He离子进行氦注入，同时用1 MeV Kr离子和16 keV He离子以1 at。％He / dpa的速率研究氦与置换的相互作用在500°C时损坏。氦气注入实验期间，氦气泡形成并隔离在位错环内，并且在环外未观察到气泡。回路尺寸随着氦浓度的增加而增加。相反，当同时用1 MeV Kr离子和16 keV He离子辐照镍时，氦气气泡在基体中均匀形成。