Corrosion behavior and protective film constitution of AlNiCoFeCu and AlCrNiCoFeCu high entropy alloy coatings

Corrosion behavior and protective film constitution of electrodeposited AlNiCoFeCu and AlCrNiCoFeCu high entropy alloy (HEA) coatings were investigated. The corrosion parameters determined using the potentiodynamic polarization and weight loss measurement techniques showed that the corrosion resistance of Cr-containing AlCrNiCoFeCu HEA coating is higher than that of AlNiCoFeCu HEA coating in 3.5 wt.% NaCl solution. The surface analysis showed that the Cr in AlCrNiCoFeCu HEA coating enhanced the formation of metallic oxides film, over the coating surface, that reduced ionic diffusion and improved the coating corrosion resistance of AlCrNiCoFeCu HEA when compared to the AlNiCoFeCu HEA coating.