Expansion of irradiation data by interpolation and extrapolation for design of graphite components in high temperature gas-cooled reactor; Evaluation on IG-110 graphite irradiation data for component design

Kunimoto, Eiji; Shibata, Taiju ; Shimazaki, Yosuke ; Eto, Motokuni*; Shiozawa, Shusaku; Sawa, Kazuhiro; Maruyama, Tadashi*; Oku, Tatsuo*

The VHTR is being focused and developed internationally. In Japan, the HTTR of the JAEA is in operation, and research and development for the development of commercial HTGRs are carried out. Nuclear graphites are used for core components of the HTGRs and expansion of irradiation data is necessary when enough irradiation data are not established, because the graphite components in the HTGRs are used at severer condition than that in the HTTR. The necessary database can be established by expansion of existing irradiation data with appropriate interpolation and extrapolation methods. This paper shows the reasonable interpolation and extrapolation method for IG-110 graphite which is used for the HTTR and a major candidate for the VHTR. The interpolation and extrapolation method was developed so as to be general by using the irradiation data of the other graphites. As a result, irradiation properties of the IG-110 graphite were successfully expanded to the VHTR condition for the first time and the irradiation properties being necessary for the design could be developed.