Corrosion inhibitor screening for AA6014 aluminum alloy under different ambient conditions using a novel multielectrode methodology

Abstract

Atmospheric corrosion, an electrochemical phenomenon, initiates the degradation of materials, primarily metals, through their interaction with environmental droplets or aerosols. This degradation extends to various aspects such as material performance, longevity, and safety, emphasizing the critical need to comprehend and inhibit corrosion, particularly in industrial and environmental settings. Structural aluminum alloys, prominently used in aerospace, automotive, and marine industries, undergo extensive scrutiny due to their susceptibility to atmospheric corrosion. Nonetheless, the absence of suitable electrochemical techniques capable of accommodating droplet volumes underscores the urgent need for advancements in corrosion research. This paper introduces an innovative and efficient multielectrode cell setup aimed at rapid screening of droplet and thin film electrolyte volumes, presenting a new high-throughput screening method. Utilizing AA6014 as a substrate, this paper demonstrates a proof of concept for this methodology. It explores the influence of a crucial parameter, pH, while considering the effects of evaporation and secondary spreading. Various organic corrosion inhibitors, including some well-known inhibitors, were examined to evaluate the impact of chemically related structures on inhibition efficiency. This investigation predominately focuses on comparing and discussing differences and similarities in inhibition performance between bulk and droplet volumes. Ultimately, this comprehensive investigation aims to enhance the understanding and management of corrosion inhibition in droplet and thin film environments.