Technical Note: The Mechanism of Cathodic Disbondment of Protective Organic Coatings—Aqueous Displacement at Elevated pH

This paper will present evidence indicating that the root cause of cathodic disbondment of protective organic coatings is the displacement of the coating by a high pH aqueous film between the coating and the substrate. This is based upon experiments involving delamination caused by soaking in ammonium hydroxide solution and experiments involving cathodic delamination in a noncorrosive medium at low applied potential.