Super ODS steels R&D for fuel cladding of next generation nuclear systems, 9; Damage structure evolution under electron-irradiation

原子力システム高効率化に向けた高耐食性スーパーODS鋼の開発,9; 電子線照射による組織損傷

大貫 惣明*; 橋本 直幸*; 鵜飼 重治*; 木村 晃彦*; 井上 賢紀 ; 皆藤 威二 ; 藤澤 敏治*; 奥田 隆成*; 阿部 冨士雄*

Onuki, Somei*; Hashimoto, Naoyuki*; Ukai, Shigeharu*; Kimura, Akihiko*; Inoue, Masaki; Kaito, Takeji; Fujisawa, Toshiharu*; Okuda, Takanari*; Abe, Fujio*

重金属冷却高速増殖炉及び超臨界水冷却高速増殖炉用の燃料被覆管として、優れた高温強度と高耐食性の両方を兼ね備えた酸化物分散強化型フェライト鋼(スーパーODS鋼)の開発を進めている。本報では、開発中のスーパーODS鋼の電子線照射による組織損傷について強化した結果について報告する。

The aim of this study is to survey microstructural properties and irradiation response of advanced high Cr and Al ODS steels. The effects of minor element addition and heat-treatment are also investigated. In these steels, black dots-like dislocation loops were formed around oxide particles during electron irradiation, and then the behavior depended on the type of additional elements, but the irradiation resistance was confirmed generally. The irradiation response was not sensitive as the heat-treatment, but the minor element addition (Zr and Hf) showed an intensive suppressing the loop growth. The results suggest that a large number of oxides enhanced the mutual recombination of the irradiation-induced point defects, especially at their surface.