ACCELERATED LIFE TESTING

Cathodic Disbondment Testing (ASTM G 80 and ASTM G 95)

This method is used to evaluate the long-term performance of barrier coatings used to protect metal pipe used in underground applications. The test consists of placing a test specimen coated with the candidate material in series with a magnesium anode as part of a galvanic cell. The electrolyte is a mixture of various salts including NaCl, KCl, and sodium bicarbonate. Prior to placement in the electrolyte the coating is intentionally damaged (holiday) in one or more locations to provide a site where edge corrosion may occur. The sample is then allowed to remain in the electrolyte for 30 days after which time the edges of the holiday(s) are evaluated to determine the extent of disbondment.

Index of Accelerated Life Testing