Effect of Relative Humidity on the Initial Atmospheric Corrosion Behavior of Zinc during Drying

Abstract

The effects of relative humidity on the initial atmospheric corrosion of zinc during drying of chloride-contained absorbed thin electrolyte layer was investigated by mass loss, scanning electron microscopy (SEM), cathodic polarization curves, pre-Tafel polarization curves fitting method and electrochemical impedance spectroscopy (EIS). The results showed that the zinc corrosion rate decreased with increasing relative humidity in the first 2 h. After 72 h of exposure, the corrosion rates of zinc were ranked as: 75% RH < 85% RH < 97% RH. And the morphology of corrosion products at 75% RH appeared more compact than that of 85% and 97% RH. © 2013, The Electrochemical Society, Inc. All rights reserved.