Approaches to investigate delamination and interfacial toughness in coated systems: an overview

Jinju Chen (1) , Sj Bull (2)

1 School of Engineering & Materials Science, Queen Mary
2 School of Chemical Engineering and Advanced Materials

The fundamental property which often dictates the performance of a coating is its adhesion to the substrate and thus there are many techniques to measure adhesion. The choice of methods is dependent on many factors such as mechanical properties of the coating and substrate, the interface properties, the microstructure of the coating/substrate system, residual stress, coating thickness and the intended application. Most tests aim to introduce a stable interfacial crack and make it propagate under controlled conditions and model this process to determine adhesion. The corresponding models are either stress analysis based or energy-based. With the advent of miniature systems and very thin functional coatings, there is a need for characterization of adhesion at small length scales and some specific tests have been developed which are not appropriate for thicker coatings. Among these, indentation and scratch methods have the widest range of applicability but it is necessary to analyze the failure mechanisms before choosing an appropriate model to extract adhesion parameters. This paper reviews the main quantitative adhesion tests for coatings and highlights the tests which can be used to assess submicron coatings and thin films. The paper also highlights the modelling and analysis methods necessary to extract reliable adhesion properties illustrating this with examples for submicron coatings on silicon and architectural glass.

Mots clés: Coatings; Interface; Adhesion; Fracture

Jinju Chen, Sj Bull. Approaches to investigate delamination and interfacial toughness in coated systems: an overview. Journal of Physics D: Applied Physics, 2011, 44 (3), pp.34001. ⟨10.1088/0022-3727/44/3/034001⟩. ⟨hal-00588673⟩