Superior microwave absorption properties of carbon-coated FeSiCr micro flakes

Carbon-coated ferromagnetic alloys can protect from microwave radiation due to their tunable electromagnetic parameters and multiple loss mechanisms. We prepared carbon-coated flaky FeSiCr (FFSC@C) powders by the encapsulation and thermal decomposition of epoxy resin. The crystallization degree and thickness of carbon coating were tuned to optimize the microwave absorption of FFSC@C. The phase composition, morphology, magnetic properties, electromagnetic parameters, and microwave absorption properties of FFSC@C were comprehensively investigated. The oriented flaky FeSiCr possessed strong attenuation capacity, the amorphous carbon improved the impedance matching of flaky FeSiCr. The sample carbonized at 500 degree celsius, with the epoxy addition amount of 45 wt% exhibited a broad effective absorption bandwidth of 5.60 GHz at a thickness of 2.4 mm. Compared with other absorbents, the FFSC@C exhibited stronger absorption capacity at a lower thickness and filler loading in the X -band (8-12 GHz). This work demonstrated the facile fabrication of a highperformance carbon-coated ferromagnetic microwave absorber.