Evaluating the Impact of Key Variables on Inhibitor Functionality Under Droplet Conditions

This study investigates droplet-induced corrosion, a localized corrosion phenomenon driven by oxygen depletion within electrolyte droplets, distinct from bulk volume corrosion. To evaluate the performance of corrosion inhibitors under droplet conditions, a rapid screening electrochemical test method was employed, using a two-electrode setup to monitor corrosion currents. The study examined systematically different exposure environments including dissolved oxygen, pH, electrolyte molarity, and droplet geometry as key factors influencing atmospheric corrosion. Results show that dissolved oxygen levels significantly affect corrosion mechanisms, while larger droplets amplify the Evans droplet effect. Importantly, effective corrosion inhibitors mitigate this effect by reducing the cathodic reaction rate in droplet conditions. These findings advance the understanding of droplet corrosion mechanisms and provide insights into designing sustainable protection strategies to improve the longevity of steel structures in aggressive environments.