Displacement and helium-induced enhancement of hydrogen and deuterium retention in ion-irradiated 18Cr10NiTi stainless steel

There is strong interest in the accelerator-driven transmutation technology community on the synergistic effects of displacement damage and co-generated helium and hydrogen on property changes such as void swelling, irradiation creep, hardening, and possibly on corrosion and cracking. Substituting deuterium for protium offers advantages in experimental studies of the helium–hydrogen-damage synergisms. The influence of preimplanted helium and self-ion induced damage on deuterium trapping in 18Cr10NiTi stainless steel was studied using thermal desorption spectrometry, the nuclear reactions 3He(D, p)4He and D(3He, p)4He, and transmission electron microcopy. Reemission, retention and evolution of depth distribution profiles of deuterium in 18Cr10NiTi SS were studied for 10 keV D 2 + and 10 keV He+ implantation at room temperature followed by annealing at 300–1500 K. The amounts of trapped and released deuterium and helium atoms were measured as a function of implantation dose at various temperatures. It was found that retention of hydrogen and deuterium is strongly enhanced by the presence of large amounts of helium and also strongly enhanced by damage introduced by 2 MeV Cr3+ ions. These results are consistent with recent observations of hydrogen storage in stainless steels after irradiation in LANSCE with high energy protons and neutrons and also after irradiation in light water reactors.