圧力容器モデル合金の照射脆化に及ぼすＭｎ，Ｎｉ添加効果
概要
The neutron irradiation of Fe based model alloys and steels leads to an increase in the ductile-to-brittle transition temperature (DBTT) with a decrease in the upper shelf energy. It is well known that the Cu content has a strong influence on the embrittlement phenomena; especially, the Cu-rich precipitates have been thought to be directly responsible for the embrittlement. In contrast, mechanical property studies for the steels with different Cu levels have shown that so-called matrix defects are dominant in the embrittlement of low-Cu steels as well as in that of high-Cu steels at high fluences. To study the effect of dislocation loop formation at high fluencies and high flux on radiation hardening in those steels, neutron and ion irradiation have been conducted for Fe-based model alloys with different Ni and Mn levels. The neutron irradiation was performed in BR2 (BAMI and CALLIST) . Hardness tests were conducted before and after the ion irradiation at room temperature. After the irradiations, microstructure was observed by Cs?corrected microscope (ARM200FC).
