Preparation and microwave absorption properties of pitch carbon coating FeNi/ Fe3O4 particles

摘要

Using petroleum pitch as carbon sources, pitch carbon coating FeNi/Fe3O4 particles with 20wt%, 30wt%, 40 wt% carbon were separately prepared by a liquid phase method. Their structures, morphology and microwave absorption properties were investigated and the impacts of the carbon content on the electromagnetic properties were discussed in the frequency ranges of 2-8 GHz. It can be demonstrated that the composites exhibit superior microwave absorption performance in low frequency and the microwave absorption properties of composites decrease with the increasing carbon content from 20 to 40 wt %.For the composites with 20wt% carbon, the maximum RL reaches -26.9 dB at 3.4 GHz with a matching thickness of 5mm and the absorption bandwidths exceeding -10dB are more than 5.2GHz (from the 2.6 to 8GHz) with the thickness of 2-5mm.