LAUSR

The flaky carbonyl iron powder (CIP) was prepared by high-energy ball milling, and then the CIP/FeSiAl composites were obtained with different mass ratios by ultrasonic mixing method in this paper. Here, scanning electron microscopy and Fourier transform infrared spectroscopy were used to demonstrate the microstructure and functional groups of the prepared samples. The element distribution was detected by energy dispersive spectrometer. The complex permittivity and permeability were determined by vector network analysis in the frequency range of 1–18 GHz. The reflection loss (RL) was calculated according to the transmission line theory. The composites exhibit typical flake shapes, which can exceed Snoek limit due to the enhanced shape anisotropy. The results show that the absorption property of composites can be tuned in S-band by changing the mass ratio of CIP and FeSiAl. For the composite (mass ratio of 1:4) with the thickness of only 1 mm, the RL reaches a minimum of − 6.4 dB at 2.3 GHz. Moreover, the absorption bandwidth less than − 5 dB is 2.3 GHz. This study indicates that the CIP/FeSiAl composites can be potential microwave absorbers in S-band.