Microstructural evolution in proton irradiated NF616 at 773K to 3dpa

Abstract Ferritic–martensitic (FM) steels have been widely considered as structural materials for future fusion and fission systems due to their excellent swelling resistance and other properties under irradiation. NF616 is a newer generation FM steel that provides higher allowable operating temperatures, but there is limited information on the development of irradiated microstructures or associated mechanical properties in NF616. Studying the irradiation-induced defects as a function of dose could help to better understand the mechanisms of damage evolution. Proton irradiation at 773 K, up to 1, 2 and 3 dpa, was performed on NF616 to investigate damage evolution at different doses. Irradiation-induced defects, such as clusters, loops and dislocations, were investigated.