Radiation effects at fusion reactor He : dpa ratios: Overview of US/Japan spectrally tailored experiments

Abstract

Spectrally tailored experiments in the Oak Ridge reactors ORR and HFIR are being used to determine the properties of austenitic stainless steels in the relatively unexplored radiation damage regime represented by the proposed ITER first wall and blanket design. These collaborative US/Japan experiments reproduce the temperature (60 to 400°C), damage rate (~1 MW y/m 2), neutron fluences (10 to 30 dpa) and helium generation rates (10 to 15 appm/dpa) typical of the ITER environment. The status of these experiments is described. Following irradiation in the ORR to ~8 dpa, data have been obtained on the tensile, swelling, and irradiation creep properties for a variety of austenitic stainless steels. These data are being utilized in the development of design equations. The experiments have been re-encapsulated in assemblies designed for insertion into the new RB∗ irradiation facilities when the HFIR restarts.