Theoretical design and preparation of SiC whiskers catalyzed by Fe-oxides on carbon fibers

This work reported an in-situ vapor-liquid-solid (VLS) preparation method of SiC whiskers (SiCw) catalyzed by Fe-oxides on carbon fibers, which could provide a method for preparing SiCw/carbon fiber composites. The mechanism of the SiCw was theoretically designed and then experimentally validated using XRD, SEM, and TEM. Fe2O3 was chosen as a Fe-oxide catalyst and directly loaded on carbon fibers by the impregnation process. The results showed that SiCw were successfully prepared on carbon fibers at 1600 C under the protection of flowing nitrogen, utilizing quartz and graphite as gas-phase generation sources. The prepared SiCw were beta-SiC and grew along the (111) crystal plane, with spherical droplets on top formed by Fe2O3 catalysts. SiCw were micro structurally observed to have widths of 500-1000 nm and lengths of more than 15 mu m, respectively.

Automated summary

This study reported a method for preparing SiC whiskers on carbon fibers using in-situ vapor-liquid-solid (VLS) process, and the mechanism of this method was experimentally validated. The prepared SiC whiskers exhibited favorable microstructure and were successfully loaded on carbon fibers.