Microstructure and thermal stability of low-oxygen SiC fibers prepared by an economical chemical vapor curing method

Continuous SiC fibers (SiC-CVC fibers) with low oxygen content (~2 wt%) were prepared by pyrolysis of polycarbosilane (PCS) fibers cured with chemical vapor curing (CVC). PCS fibers were cured by cyclohexene vapor as curing agent. Their structure and properties were compared with those of SiC fibers obtained from electron beam irradiation curing (SiC-EB fibers). SiC-CVC fibers were similar to SiC-EB fibers, with distinctly better thermomechanical stability than that of fibers cured by thermal oxidation curing (commercial KD-I fibers). CVC is a more economical and practicable approach for preparing high-performance SiC fibers than other strategies.