Irradiation effects of carbon fibers in C/SiC composites

Understanding the radiation-induced microstructure evolution of carbon fibers is crucial for C/SiC composites as they are considered promising structural materials for high-temperature gas-cooled nuclear reactors. In this study, M55J C/SiC and T300 C/SiC composites were irradiated up to 9.8 dpa at 350 degrees C. AFM results suggested that both two carbon fibers shrank axially after irradiation. At a given irradiation dose, the shrinkage of M55J fibers was slightly lower than that of T300 fibers. Detailed microstructure characterization further revealed that the graphite structure in both two carbon fibers was disrupted due to ion irradiation. In contrast to M55J fibers, the ordering degree for T300 fibers increased at low dose range and diminished at higher doses. Possible mechanisms for the healing process occurring in T300 fibers were discussed.

Automated summary

In this study, the radiation-induced microstructure evolution of M55J and T300 carbon fibers in C/SiC composites was investigated. Both carbon fibers exhibited axial shrinkage after irradiation, with M55J fibers showing slightly lower shrinkage compared to T300 fibers. Detailed microstructure characterization revealed disruptions in the graphite structure of both carbon fibers due to ion irradiation. The ordering degree of T300 fibers increased at low doses and decreased at higher doses, and possible mechanisms for the healing process in T300 fibers were discussed.