Microwave absorption capability of microcapsules by coating FeSiAlCr with SiO2

Abstract Electromagnetic wave absorption of microcapsules by coating FeSiAlCr with SiO 2 is investigated. The absorption amplitude of the microcapsules is found to increase significantly in the lower frequency of microwave compared with the corpuscles of FeSiAlCr alloy. Reflection loss (RL) exceeding −10 dB can be obtained for all frequencies within 2.6–7.3 GHz, covering half of the S-band, and the whole C-band when the absorber layer thickness is 2 mm. The maximum RL can exceed −18 dB at 4.3 GHz, while the RL is only −4 dB with the corpuscles of FeSiAlCr alloy. The reason is that the microcapsules's conductance is decreased and the absorption of electromagnetic wave in the microcapsule materials is easier.