Mechanical properties of neutron irradiated SiC fibers

Abstract

SiC fibers were irradiated at neutron fluences of 8 × 10 23 and 2 × 10 24 n/m 2 in JMTR ( E >1 MeV). The tensile strength of SiC fibers measured at gauge length of 5 mm essentially unchanged after the neutron irradiation, but the strength at a length of 25 mm and 50 mm increased by 40% and 25% after the irradiation, respectively. The tensile strength variations of the irradiated SiC fibers with respect to gauge length were examined in terms of Weibull statistics. The Weibull modulus of the tensile strength in the SiC fibers increased slightly by the neutron irradiation. SiC fibers and SiC fiber reinforced aluminum preform wires (SiC/Al) were irradiated in JOYO ( E > 0.1 MeV) at neutron fluences of 1 × 10 24 , and 1 × 10 24 and 1 × 10 25 n/m 2 , respectively. The mechanical properties of the irradiated SiC fibers and the SiC fibers extracted from the irradiated SiC/Al preform wires were essentially unchanged in comparison with the unirradiated SiC fibers.