| Abstract Scope |
Ion irradiation is often used as a substitute for in-reactor testing when studying radiation effects in materials. However, the radiation damage process is affected by several independent variables including irradiation dose rate, irradiation temperature, and the production of helium by nuclear reactions. In this study, samples of 800H alloy were irradiated in the BOR-60 reactor to 17 dpa at nominally 376 °C, while complementary samples were irradiated to similar doses with dual beam 5 MeV Fe and energy-degraded 1.95 MeV He ions at the Michigan Ion Beam Laboratory. The helium co-injection ranged from 0 to 276 appm. A temperature shift was used to compensate for the higher dose rate, and ion irradiation temperatures ranged from 430 to 500 °C. The irradiated microstructure, including faulted dislocation loops, cavities, precipitates, and grain boundary segregation, was characterized with transmission electron microscopy. The microstructures formed under dual ion beam and neutron irradiations are compared. |