Preparation and Microwave-Absorbing Properties of Some Non-Circular SiC Fibers

Polycarbosilane was melt-spun through different non-circular spinneret, and then the green fibers were obtained. With the process of being cured and heated to a specific temperature, ribbon, trilobal, quatre- foil, pentalobal, C-shaped and hollow SiC fibers were prepared. The shape of non-circular SiC fibers was characterized. Electromagnetic parameters and microwave-absorbing properties of these fibers were analyzed. It was found that permittivity of foliaceous SiC fibers increases with increase of vane number in the case of having the same surface area. Permittivity of C-shaped SiC fibers is greater than hollow ones while tanδ is less. Microwave-absorbing property of structural absorbing composites could be enhanced using different non-circular SiC fibers to match impedance.