Preparation of Low Oxygen SiC Fiber by Dry Spinning

Dry spinning performance of PCS solution and self crosslinking process of the PCS fiber as-spun were studied by viscosity,gel content and XRD techniques.The composition,structure and mechanical properties of SiC fibers were also characterized.Results show that the optimum spinning viscosity of PCS/xylene solution is 18.0-22.0Pa.s,self crosslinking process of the PCS fiber by dry-spun begins at 250℃during pyrolysis process,and finishes at 550℃to form a network structure which does not melt or dissolue.The oxygen content of the final SiC fibers is decreased to about 3.6wt%.SiC fibers prepared by dry spinning have a betterβ-SiC microcrystalline structure and show better oxidation resistance than those prepared by the oxidation curing.