[SY-B6] Ion Irradiation as a Surrogate for Reactor Irradiation: The Expected and the Surprises
Invited
Reactor core materials in both fast reactors and LWRs granted life extension must withstand irradiation to high doses at high temperature. Ferritic-martensitic (F-M) alloys are attractive candidates for structural components of fast and thermal reactors, and high chromium and high nickel-containing austenitic steels are potential replacement alloys for LWR core materials. Both require high dpa, for which ion irradiation is ideally suited. To simulate the reactor radiation environment, self-ion irradiation and He injection are conducted simultaneously into both F-M and austenitic alloys. Reactor irradiations of the same alloys have been, or are being conducted in the BOR-60 fast reactor to assess the capability of ion irradiation to emulate the evolution of reactor generated microstructures and mechanical properties. Computational models for defect cluster evolution are being developed and benchmarked against experimental data to ultimately provide predictive capability for the response of both microstructure (loops, voids, precipitates, etc.), and mechanical properties (hardening, ductility, slip behavior) to irradiation. To date, agreement is quite promising with many outcomes ocurring as expected. However, there are a number of observations or results that are unexpected. Results will be presented on the microstructure and mechanical property evolution in ion and reactor irradiation integrated with computational modelling in an effort to understand the extent to which ion irradiation can be used as a surrogate for reactor irradiation, and to illuminate processes that are not well understood.