Irradiation response in weldment and HIP joint of reduced activation ferritic/martensitic steel, F82H

溶接及び固相拡散接合した低放射化フェライト・マルテンサイト鋼F82Hの照射応答

廣瀬 貴規; Sokolov, M. A.*; 安堂 正己; 谷川 博康; 芝 清之; Stoller, R. E.*; Odette, G. R.*

Hirose, Takanori; Sokolov, M. A.*; Ando, Masami; Tanigawa, Hiroyasu; Shiba, Kiyoyuki; Stoller, R. E.*; Odette, G. R.*

The objective of this work is to investigate irradiation response in the joints of F82H. The joints of F82H were prepared using TIG welding, EB welding and Hot-Isostatic-Pressing (HIP). As for weld joints, mechanical specimens were cut out of weld-metal (WM), heat-affected-zone (HAZ). These specimens were irradiated in an instrumented irradiation capsule, RB-15J in HFIR at Oak Ridge National Laboratory. The irradiation temperature was controlled at 573 and 673 K using liquid lithium as a heating medium, and the irradiation dose was up to 6 dpa. Tensile tests after 573 K irradiation revealed that the hardening in WM and base metal (BM) are greater than 300 MPa. On the other hand, HAZ exhibits about half of that of the WM and BM. Since the HAZ is the weakest part in the joint even before irradiation, neutron irradiation significantly enhances the weakness of the HAZ and it could be in danger of local deformation at this region.