Corrosion Behaviors and Mechanism of Crfeni2 Based High-Entropy Alloys

Abstract

A novel CrFeNi2-based alloy system was designed and the corrosion behaviors were investigated in 3.5 wt.% NaCl solution. The single-phase FCC  was observed in CrFeNi2 and CoCrFeNi2, while the lamellar eutectic structure composed of dual-phase formed in AlCoCrFeNi2.  Due to the compact and stable oxide films composing of protective oxide/hydroxide, the CrFeNi2 alloy demonstrated the widest passivation region (1035 mV), the highest pitting potential (954 mV), and an outstanding repassivation ability, outperforming previously reported conventional alloys and some other HEAs. This research will clarify the comprehending of corrosion behaviors through different phases and the effect of element on corrosion resistance.

Keywords: High-entropy alloys, Phase, Repassivation, Passivity.