Corrosion and passive behavior of AlxCrFeNi3−x (x = 0.6, 0.8, 1.0) eutectic high entropy alloys in chloride environment

Abstract

The corrosion and passive behavior of the as-cast Al x CrFeNi 3−x (x = 0.6, 0.8, 1.0 in molar ratio) high entropy alloys in 3.5 wt% NaCl solution at room temperature was investigated by the electrochemical impedance spectroscopy , potentiodynamic polarization measurement, Mott-Schottky measurement, X-ray photoelectron spectroscopy tests, and scanning Kelvin probe force microscopy. The increase of the Al content resulted in the decrease in corrosion resistance , which might be attributed to the reduction of stability and protection of passive films caused by composition difference. Furthermore, the p-type and n-type semiconductor properties of passive films were discussed.