Effect of the microstructure on the corrosion behavior of a AlCuNiMn and AlCuNiMnSi high entropy alloys in a 3.5 wt% NaCl solution

The AlCuNiMn and AlCuNiMnSi high-entropy alloys are fabricated in near-equiatomic proportions by arc melting and heating at 600, 800, and 1000°C for 24 hours in air. The effect of Si and heating influences the microstructure and corrosion behavior in 3.5wt% NaCl solution at room temperature. Increasing the oxidation temperature of the AlCuNiMn provides more uniformity to the microstructure and decreases the corrosion rate. The addition of Si alters the microstructure morphology by redistributing the other elements, decreases the void size, introduces a new MnSi microconstituent, and overall enhances the corrosion resistance.