Excellent electromagnetic-wave absorbing performances and great harsh-environment resistance of FeCoNiCrxMn high entropy alloys

FeCoNiCrxMn (x = 0.0, 0.6, 0.8, 1.0) high-entropy alloys (HEAs) were prepared by a 3D high-energy ball -milling method. The phase structure, grain size, crystallinity, morphology, static magnetic properties, cor-rosion resistance, oxidation resistance and electromagnetic properties of FeCoNiCrxMn HEAs are in-vestigated in detail by modulating Cr contents. FeCoNiCrxMn HEAs had the phase transformation from FCC to BCC with the increase of Cr contents, which caused abnormal change of both static magnetic properties and corrosion resistance. The introduction of Cr is beneficial to improve the corrosion resistance and oxi-dation resistance of the alloys. In addition, FeCoNiCrxMn HEAs had excellent electromagnetic-wave ab-sorption performances. The minimum reflection loss (RLmin) of FeCoNiCr0.6Mn reached - 66.9 dB at 4.9 GHz with a thickness of 2.8 mm, and FeCoNiCr0.8Mn had the RLmin of - 57.4 dB at 5.2 GHz with a thickness of 3.3 mm. This study shows that FeCoNiCrxMn HEAs have practical application prospect due to the excellent electromagnetic-wave absorbing performances and great harsh-environment resistance. (c) 2022 Elsevier B.V. All rights reserved.

Automated summary

FeCoNiCrxMn high-entropy alloys (HEAs) prepared by a 3D high-energy ball-milling method exhibit phase transformation, abnormal changes in static magnetic properties, and corrosion resistance modulation with the variation of Cr contents. The addition of Cr improves the corrosion resistance and oxidation resistance of the alloys, which also show excellent electromagnetic-wave absorption performances.