Status and key issues of reduced activation ferritic/martensitic steels as the structural material for a DEMO blanket

Tanigawa, Hiroyasu; Shiba, Kiyoyuki; Mslang, A.*; Stoller, R. E.*; Lindau, R.*; Sokolov, M. A.*; Odette, G. R.*; Kurtz, R. J.*; Jitsukawa, Shiro

ITER construction was started, and R&D toward DEMO shifted to more practical stage. On this stage, the candidate material for DEMO blanket have to be the one which have sound engineering bases to be ready for engineering designing activity for DEMO reactor in 10 years. Reduced activation ferritic/martensitic (RAFM) steels, such as F82H (Fe-8Cr-2W-0.2V-0.04Ta) or EUROFER97 (Fe-9Cr-1W-0.2V- 0.12Ta), is the only material which currently have enough potential to meet this requirement, and selected as the target material in the R&D on materials engineering for DEMO blanket under the International Fusion Energy Research Centre (IFERC) project in the Broader Approach (BA) activities between EU and Japan. In this paper, current status of RAFM R&D is overviewed especially on fabrication technology, inspection/testing technology, and material database. Overview on irradiation effect study is also provided.