Tuning the Al content for flake Fe3Al powder to achieve wideband electromagnetic wave absorption

Fe 3 Al powders with different Al contents were prepared by a mechanical alloying and ordering process. The obtained flake-like structure has the average size of approximately 2 µm and the average thickness of around 300 nm. The Al content affects the magnetic properties of the obtained samples. With the increase of Al content from 22 to 30 at.%, the saturation magnetization of the sample increases from 161.9 to 167.5 emu/g. However, when the Al content is further increased to 32 at.%, the saturation magnetization decreases to 163.3 emu/g. When the Al content is 30 at.%, the flake Fe 3 Al powder has a minimum reflection loss value of − 50.5 dB. When the thickness is 1.25 mm, the bandwidth is as large as 6.0 GHz with a reflection loss value more negative than − 10 dB. The excellent electromagnetic wave absorption performance is attributed to the best impedance matching ratio and the excellent attenuation coefficient.