Function of Si on the high-temperature oxidation of FeCoNiMnSix HEAs with excellent electromagnetic-wave absorption properties

FeCoNiMnSi x (x = 0.1, 0.2, 0.3, 0.4, and 0.5) HEAs were synthesized by utilizing a novel high-energy ball-milling technique. When the Si content reached 0.3, the phase structure will transform from FCC to BCC. In terms of high-temperature oxidation resistance, Si may dramatically minimize the oxidation level of the alloys at high temperatures, hence improving the high-temperature oxidation resistance . The addition of Si to the alloys had slight influence on the corrosion resistance . Additionally, incorporating an appropriate amount of Si may also reduce magnetic loss, promote impedance matching, and improve electromagnetic-wave loss capabilities. FeCoNiMnSi 0.3 exhibits good electromagnetic-wave absorption capability with a minimum reflection loss value of − 48.6 dB at 4.24 GHz and an effective absorption width of 4.81 GHz at 2.03 mm thickness. This study is necessary for the investigation of electromagnetic-wave materials with practical applications at high temperatures.