Application of Flaky Reduced Iron Powders and Their Composites for Highly Effective Microwave Absorption Materials

Abstract

On the basis of replacing carbonyl iron powders with reduced iron powders which is environmentally friendly in the production process and has low cost, the problems of poor impedance matching and poor oxidation resistance of iron powders are improved by anisotropy and core-shell structure construction. The results show that the microwave absorption performance of the flaky reduced iron powders are improved obviously after coating of SiO2 and carbon shell successively. When the absorber thickness is 2.00 mm and the frequency is 13.3 GHz, the minimum RL value reaches −47.72 dB, and the effective absorption bandwidth is 4.9 GHz (10.6 GHz to 15.5 GHz).