Evaluation of adhesion/cohesion bond strength of the thick plasma spray coatings by scratch testing on coatings cross-sections

The possibility of adhesion/cohesion bond strength evaluation of thick plasma spray coatings with scratch tester, according to the ISO working draft (ISO/WD 27307), was analyzed and compared with the standard test method (ASTM C 633). Four different coatings deposited with atmospheric plasma spraying were used. The results showed that scratch testing could be used as an efficient method for evaluation of thick plasma spray coatings cohesion. It is a relatively easy and quick test method, and for practical application it could be also used as a supplement of some standard test method as a coating characterization and quality control technique. (C) 2011 Elsevier Ltd. All rights reserved.