A novel approach used to study the corrosion susceptibility of metallic materials at a dynamic seawater/air interface

Abstract

A novel device is constructed to study the localized corrosion susceptibility of 2024 aluminum alloy at a dynamic seawater/air interface. Corrosion in three distinct regions are identified: full immersion region, seawater/air interfacial region (alternant wet/dry region), and atmosphere region. The corrosion process in the interfacial region over time was studied by EIS and the corrosion product was characterized by SEM. Experimental results revealed that, a layer of intense and uniform corrosion product was formed on the seawater/air interfacial region, due to the oxygen enrichment in that region. Pitting corrosion was more severe in the full immersion region than that in the seawater/air interface, as verified by a lower charge transfer resistance and more severe pitting corrosion and intergranular corrosion extent.

Keywords

• Aluminum alloy
• Seawater/air interface
• Localized corrosion
• EIS