Enhanced impedance matching and microwave absorption properties of the MAMs by using ball-milled flaky carbonyl iron-BaFe12O19 as compound absorbent

The electromagnetic (EM) and microwave absorption properties of microwave absorbing materials (MAMs) with ball-milled flaky carbonyl iron-BaFe12O19 (FCI-BaFe12O19) as compound absorbents and silicon resin as matrix were investigated in the frequency range of 2.6-18.0 GHz. Results indicate that efficiently enhanced impedance matching and microwave absorption of the FCI-BaFe12O19/silicon resin composites were obtained due to the microstructure and synergism of FCI-BaFe12O19 particles as well as the inherent electromagnetic properties. And the values and frequency dependencies of EM and microwave absorption properties of the MAMs can be simply adjusted by filling FCI-BaFe12O19 absorbents with different mass ratios. When the mass ratio was 6:1, the reflective loss (RL) values below −5dB were obtained in the frequency range of 5.4-18 GHz, 4.9-18 GHz and 4.5-18 GHz with the thicknesses of 1.0 mm, 1.1 mm and 1.2 mm, respectively. Moreover, RL values are all below −8dB in military X band, meaning that 85% EM wave can be absorbed. The advantages demonstrate that this FCI-BaFe12O19 compound absorbent can be acted as a potential candidate for fabricating microwave absorbing material with thin-thickness and broadband absorption, especially for practical application.