Ranking high-quality paint systems using EIS. Part II: defective coatings

The assessment of the protective performance of paint coating systems as described in Part I of this work is a valuable procedure for intact coatings. However when defects are present in the paint films the significance of tests using intact coatings is limited, since the mechanisms involved in degradation/healing of the painted metal could change. Thus the full knowledge of the degradation behaviour of coated metals should involve both situations, requiring the use of the two types of specimens, i.e., with intact and defective coatings. In order to meet the industry requirements in terms of time, accelerated cabinet tests in scribed coated specimens can be associated with intermediate temperature tests in intact coatings using EIS measurements (Part I). (C) 2002 Elsevier Science Ltd. All rights reserved.