Corrosion behavior of VCrFeCoNi medium-entropy alloy in chloride solution

The present work investigates the corrosion properties and passivation layer of VCrFeCoNi medium-entropy alloy (V-MEA). The V-MEA exhibits the corrosion current density of -0.101 mA and corrosion potential of - -0.336 V with a broad passivation region of -0.763 V from the potentiodynamic polarization measurement. The V-MEA shows the multilayer passivation with vanadium oxides-rich outer layer and chromium oxide-rich inner layer. The outer layer as a cation-selective layer defeats Cl- ions and the inner layer as an anionselective species captures the Cl- ions. Resultantly, fewer Cl- ions can go through the passivation layer, leading to the broad passivation region of V-MEA. (c) 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

The corrosion properties and passivation layer of VCrFeCoNi medium-entropy alloy (V-MEA) were investigated in this study. The V-MEA exhibited a corrosion current density of -0.101 mA and a corrosion potential of -0.336 V, with a broad passivation region of -0.763 V. The V-MEA showed a multilayer passivation with a vanadium oxides-rich outer layer and a chromium oxide-rich inner layer. The outer layer acted as a cation-selective layer to prevent Cl- ions, while the inner layer acted as an anion-selective species to capture the Cl- ions. As a result, fewer Cl- ions could penetrate the passivation layer, leading to the broad passivation region of the V-MEA.