Influence of KD-1SiC fiber volume fraction on the dielectric and microwave absorption properties of hybrid SiC fabrics/epoxy composites

In this study, hybrid silicon carbide fabrics (SiC)/epoxy composites were fabricated and analyzed. The hybrid SiC fabrics used as reinforcement in the composite was obtained by weaving two types of SiC fibers from two different suppliers: KD-1SiC fibers and SLF-SiC fibers. We have woven these two types of fibers in various proportions. Because the electrical conductivity of KD-1 SiC fiber is much higher than that of SLF-SiC fiber, we have concentrated only on the volume fraction of KD-1SiC fiber and its major influence on the electromagnetic properties of hybrid SiC fiber/epoxy composites. The results indicated that the complex permittivity of the composites increased with increasing the volume fraction of KD-1SiC fiber due to the high interfacial polarization and dielectric loss ability of KD-1SiC fiber. Though the complex permittivity of the composites can be adjusted, the absorbing properties of hybrid SiC fabrics were not greatly enhanced due to the poor impedance matching characteristics. This method provided a way to adjust the complex permittivity of radar absorbing structures.