Measurement of coating adhesion

Abstract

The ability to change the surface characteristics of a component independent of the bulk material properties by use of surface coatings has opened up many new and diverse applications in a number of technology areas [1]. There are many definitions of what is meant by surface engineering, perhaps the most appropriate is -the application and design of surface treated material systems to achieve a cost-effective performance enhancement of which neither is capable on its own. In most applications the minimum criterion for acceptable performance is that the adhesion of the coating to the substrate should be sufficient so that the coating remains in place for the lifetime of the component in its operating environment. In such developments there is a requirement to measure the level of adhesion between substrate and coating in order to guarantee that only coatings 'fit for purpose' are released for evaluation. In many instances the slow take-up of surface coating technology can be traced, in part, to a lack of end-user confidence in the quality of supplied coatings and thus it is essential that a simple and reliable adhesion test is available, which should ideally be of relevance to the intended application.The main theme of this chapter is coating adhesion, a property which is central to the functionality of the coating-substrate system. However, the nature of the interfacial region is linked to the choice of surfacing technology, so this chapter begins by briefly reviewing surfacing techniques and the failure

Interface fracture behavior of electroplated coating on metal substrate under compressive strain

“…It is well-known that the strain is closely interrelated with the calculation of fracture energy of the coating/substrate interface or the interfacial region. And the fracture energy is an accredited scale used to describe the interfacial adhesion (Rickerby, 1996;Shaw et al, 1998). So the target of this study is to calculate the fracture energy by establishing a relationship between the compressive strain and energy.…”

“…(Agrawal and Raj, 1988), scratch test (Bull and Berasetegui, 2006), indentation test (Li et al, 2002) and direct pull-off test (Rickerby, 1996). In the present study, T-bend test improved was conducted on the electroplated chromium coatings on steel substrates which are typical electroplated coating/metal substrate composite systems with strong adhesion and have been widely used in various industries.…”