Study on structural integrity of C/C composite using as core restraint mechanisms in HTGR

Tsuji, Nobumasa*; Shibata, Taiju ; Sumita, Junya ; Ishihara, Masahiro ; Iyoku, Tatsuo

The core restraint mechanisms have been made of steel materials in existing HTGR, but steel materials cannot keep tying force in higher coolant temperature over 5000C caused by rapid stress relaxation. The C/C composite is one of the attractive candidates for core restraint mechanisms because of its excellent mechanical properties in high temperature. In the present study, basic design of the core restraint mechanism using C/C composite was conducted and structural integrity of C/C composite was evaluated by FEM stress analysis with anisotropic material model. As a result, it was shown that the core restraint mechanism using C/C composite has realizable possibility to achieve high temperature coolant up to 10000C in HTGRs.