Corrosion Behavior of Al₁₀Cr₃₀Fe₂₅Mn₃₀Ti₅ High-Entropy Alloy: Microstructural, Electrochemical, and Surface Analysis

Abstract

In this work, the corrosion performance of a new developed high-entropy alloy (HEA) of the composition Al10Cr30Fe25Mn30Ti5 (at. %) was studied. The corrosion testing of the Al10Cr30Fe25Mn30Ti5 HEA was carried out in 2.5 M NaOH, 0.6 M NaCl, and in 0.5 M H2SO4. The correlation between the microstructure, elemental composition, density, hardness, and corrosion resistance of the new developed Al10Cr30Fe25Mn30Ti5 HEA was investigated. The impedance response showed protective corrosion behavior for the neutral and acidic pH, while the alkaline environment led to a passivity breakdown due to dissolution of Al forming Al(OH)3. The outcome of the presented study suggests that new developed HEA is suitable to be used in industrial environments with a neutral and acidic pH.

Keywords

• high-entropy alloys (HEA)
• electrochemical impedance spectroscopy (EIS)
• X-ray photoelectron spectroscopy (XPS)
• high-energy X-ray diffraction (HEXRD)
• passive film