Void swelling behavior of multi-ion irradiated F82H

Ando, Masami; Tanigawa, Hiroyasu; Kurotaki, Hironori

Reduced activation ferritic/martensitic steel (RAFM) is the most promising candidate for the blanket structural material in DEMO fusion reactor. Void swelling behavior as well as mechanical properties change under high dose fusion neutron irradiation is very important issue on R&D of RAFM steels (F82H). The purposes of this study are to investigate the void swelling behavior with F82H IEA, Mod-3 and BA07 heats after multi-ion-irradiation and to confirm the peak swelling temperature. From results of microstructure observation for F82H Mod-3 and BA07 heats at 470C by multi-ion beam irradiation, cavities are observed from 0.8 to 1.2m (damage level 20 dpa) from an irradiation surface at 470C irradiated specimen. On the other hand, few cavities are observed in same region at 400C irradiation. This result shows that a swelling peak temperature with F82H weldments by ion irradiation will be also around 470C.