Radiation tolerance of controlled fusion welds in high temperature oxidation resistant FeCrAl alloys for enhanced accident tolerant fuel cladding applications

Description of project: FeCrAl alloys are currently under development for nuclear power production applications due to their excellent performance in extreme environments including high temperature corrosive media. The benefits of extreme environmental compatibility can be realized in a range of nuclear reactor applications, specifically as a cladding material with enhanced accident tolerance. However, FeCrAl alloys have not been deployed in commercial nuclear applications as a range of technological issues has yet to be resolved. Two areas of primary importance are hydrogen-induced embrittlement during fabrication and radiation-induced embrittlement while in-service for FeCrAlbased weldments. In the present project, mitigation strategies based on microstructure and composition refinement have been proposed and are currently under exploration to reduce or completely eliminate both degradation modes for weldments that use FeCrAl alloys as the base metal. A multifaceted, interdisciplinary approach is in use to assess the viability of the proposed mitigation schemes including a systematic alloy development and fabrication stage, an irradiation campaign, and an extensive post irradiation examination phase.