Deuteron irradiation creep of chemically vapour deposited silicon carbide fibres
Silicon carbide composites are considered as structural materials for the first wall and blanket of nuclear fusion reactors. The effects of high-energy particle irradiation on the mechanical properties of SiC, SiC-fibres or SiC-composites have been determined predominantly in post irradiation tests. Light ion irradiation creep experiments conducted on SiC in the temperature range between 235 C and 505 C were not conclusive. The observed length increase of the specimens showed a less than linear stress dependence and was attributed to swelling of the material although a creep compliance similar to that of UO(2) at 400 C could not be excluded. In the temperature range below 1000 C, swelling of SiC occurs without an incubation dose and saturates rapidly at doses smaller than 0.5 dpa. The linear expansion observed after saturation declined from about 1% at room temperature to 0.05% at 1000 C. So, the magnitude of swelling is sufficiently high to mask the irradiation creep strain in a tension creep test where the swelling induced linear expansion adds directly to the total strain of the specimen. The opposite effect occurs in torsion tests on cylindrical specimens: the shear strain decreases if the specimen volume increases.
Bibliographic Reference: Article: Journal of Nuclear Materials (1998)
Record Number: 199810903 / Last updated on: 1998-08-07
Original language: en
Available languages: en