CATHODIC PROTECTION EFFECTS ON COATED STEEL: AN OVERVIEW

摘要

Cathodic protection and coatings, when used together, can be an effective means of corrosion protection. However, if set up improperly, excessive delamination, or cathodic disbondment, of the coating may result. Several disbondment related issues are addressed here, including possible disbondment mechanisms, effects of operating temperature, paint film thickness, current consumption characteristics, and cathodic disbondment testing methodology. Two popular ASTM methods: ASTM G8, "Standard Test Methods for Cathodic Disbonding of Pipeline Coatings," and ASTM G42, "Standard Test Methods for Cathodic Disbonding of Pipeline Coatings Subjected to Elevated Temperatures," are discussed in detail with regard to the experimental procedures used and results generated.