In-Situ Chemical Vapor Growth of Carbon-Rich Silicon Carbide Fibers Upon Pyrolysis of Polyzirconosilane

摘要

Carbon-rich SiC fibers were prepared in a cost-effective way using in-situ chemical vapor growth upon pyrolysis of polyzirconosilane at 1200 degrees C under nitrogen atmosphere, with 0.5-1 mu m in diameter and a few milimeters in length and a yield of about 30 %. The empirical formula of the fibers is Si1C6.6O0.1, and both silicon and carbon atoms inside the fibers are found to be uniformly distributed, and the free carbon atoms show a turbostratic state. The carbon-rich SiC fibers show ideal thermo-oxidation resistance at 1200 degrees C in air. Chemical vapor growth of ceramic fibers upon preceramic pyrolysis can be used to prepare high performance ceramic fibers on a large scale cost-effectively.