Influence of the composition of working fluids on flow-accelerated organic coating degradation: Deionized water versus electrolyte solution
By Zhou, Qixin; Wang, Yechun & Bierwagen, Gordon P.
Published in Corrosion Science
2012
Abstract
Corrosion protective coatings are known to degrade due to moisture exposure. To predict coatings service lifetime, acceleration tests are necessary. We employ flowing deionized water to accelerate coating degradation. Coating barrier properties are found, via electrochemical impedance spectroscopy (EIS), to decrease as flow rate (Q) increases, similar to findings for coatings in NaCl solution. EIS modulus decreases more for coatings in deionized water than those in electrolyte solution. Topographical characterizations show severe coating blistering in deionized water immersion with higher Q, but not in electrolyte solutions. Deionized water is thus believed to accelerate more aggressively the degradation than electrolyte solution.