Enhanced antioxidation and microwave absorbing properties of SiC/SiO₂ coating on carbon fiber

In the manuscript, a uniform SiC/SiO₂ coating was successfully prepared on the surface of carbon fiber by electrolytic plasma spraying method, which is beneficial to the dielectric loss and interfacial polarization. The antioxidation and absorption capacity of electromagnetic waves were greatly improved. The surface morphology, chemical composition, oxidation resistance and electromagnetic wave absorption properties of the coated carbon fibers were analyzed in detail. The effect of sample thickness on the electromagnetic wave loss was investigated in 2–18 GHz. The absorbing mechanism of the coated carbon fiber was discussed. The coated carbon fiber exhibits superior absorbing properties due to the synergistic effect of dielectric loss and reflection loss. The minimum reflection loss of − 11.6 dB at the thickness of 2.3 mm at 7.1 GHz. Meanwhile, the SiC/SiO₂ coating on carbon fiber also has oxidation resistance, which was 28% higher than the bare sample.