Silicon Carbide Fibre Production
topic
Polymer precursor route: (1) polycarbosilane (PCS) or polysilazane synthesis, (2) melt or solution spinning at 200-350°C, (3) curing (crosslinking) in air or electron beam (rendering infusible), (4) pyrolysis in inert atmosphere at 1000-1300°C forming amorphous SiC with excess carbon and oxygen, (5) optional high-temperature treatment at 1300-1800°C for crystallization (Hi-Nicalon S, Tyranno SA3). Near-stoichiometric SiC critical for creep resistance and oxidation stability. Diameter: 10-15 μm.
Role
Polymer precursor method is the only viable route for continuous SiC fibres, with composition control (stoichiometry, oxygen content) determining high-temperature performance—low-oxygen grades (<0.5 wt% O) essential for aerospace CMC requiring 1200-1400°C creep resistance.