The structure

oxygen content

heat resistance and tensile strength of SiC ceramic fibers

which were synthesized by irradiating pyrolysis of polycarbosilane precursor fibers in a nuclear reactor

were tested and analyzed.FT-IR spectra indicated thatchemical structure of the fibers was very similar to that of pure SiC

while XRD patterns suggested that β-SiC micro crystals were formed in the fibers

and their mean grain size was about 7.5nm.The oxygen content(1.69wt%?3.77wt%) was much lower than that of conventional SiC fibers by oxidation curing method(~wt15%).After the SiC fibers were heat treated at 1400°C in air for an hour or at 1600°C in Ar gas atmosphere for 30 min

their external appearance was still undamaged and dense appearances

which show that heat resistance of the SiC fibers was eximious.Tensile strength of the SiC fibers was up to 2.7 GPa

which demonstrates their mechanical properties were excellent.