Enhanced microwave absorption properties of Fe3O4-modified flaky FeSiAl

The magnetic insulator Fe3O4-modified flaky Fe85Si9.5Al5.5 (FeSiAl) powders with significantly enhanced electromagnetic wave absorption properties in the frequency range of 2-8 GHz were prepared by chemical co-precipitation. X-ray diffraction (XRD) and scanning electron microscopy (SEM) have confirmed the formation of nanoparticles Fe3O4 precipitated on the flake-shaped FeSiAl. The electromagnetic measurements of the modified flakes presents a nearly invariable complex permeability and decreased complex permittivity in the 2-8 GHz, as well as improved impedance matching performance. More importantly, an excellent microwave absorbing performance with the bandwidth (RL <−10 dB) of 5.36 GHz is achieved in modified sample with the thickness of 1.5 mm, which is a promising microwave absorbing material in 2-8 GHz.