Protective coatings are used ubiquitously as the primary means of corrosion defense for buried or immersed metallic structures. Cathodic protection is often used in conjunction with coatings as a secondary means of corrosion protection, however it can also have detrimental effects on the coating itself if not properly applied. Cathodic disbondment testing is used to measure a coating’s susceptibility to loss of adhesion to the substrate due to cathodic polarization.
NACE recently published a new cathodic disbondment test method, TM0115-2015, Cathodic Disbondment Test for Coated Steel Structures under Cathodic Protection. This research compares and contrasts NACE TM0115 to ASTM G8, Standard Test Methods for Cathodic Disbonding of Pipeline Coatings. The paper highlights the strengths and challenges of each test method as applied to coatings used in water infrastructure corrosion control.
Key words: cathodic disbondment, protective coatings, cathodic protection