Mechanical properties of neutron-irradiated carbon-carbon composites for plasma facing components

Mechanical properties of three kinds of felt-type or unidirectional carbon-carbon composites (CFC) were examined alter neutron irradiation of 2 × 1025 n/m2 (E > 29 fJ) at around 1000°C. CFCs included CX-2002U, MFC-1 and CC-312. A fine-grained isotropic graphite IG-110 was also irradiated as a reference material. Dimensional changes, Young's moduli, bending and compressive strengths were measured on these materials. The main results obtained are: (1) densification was observed for all the irradiated materials here, (2) no pronounced increases in the strengths and Young's moduli was observed for CFCs. The facts indicate that the microstructure of the CFCs examined in the present study is fairly unstable in the neutron irradiation environment.