OS0812 国内原子炉圧力容器鋼の照射脆化予測法の改定の検討

抄録

Some of the recent surveillance data of the reactor pressure vessel steels irradiated to high fluences showed larger transition temperature shifts than those predicted by the current embrittlement correlation method, JEAC4201-2007. In this paper, we will first review how embrittlement correlation methods have been developed and improved worldwide based on the knowledge at the time of development, and describe the characteristics of the embrittlement correlation method of JEAC4201-2007. Then, the results of microstructural characterization of the recent surveillance materials in Japan are briefly summarized to show the microstructural changes due to high fluences at surveillance capsule conditions, followed by the results of the re-calibration of the equation coefficients of the current embrittlement correlation method to the latest surveillance database.