Pages: 19 Published: Jan 1972
Before one can evaluate various instruments and methods for measuring the adhesion of organic coatings, it is important to have a fundamental understanding of what measuring adhesion means in the light of modem science, since so many significant discoveries have been made within the past decade. Only after we have this understanding can we appreciate which methods are useful and which have little or no practical value. ASTM Designation D 907, Definition of Terms Relating to Adhesion, defines adhesion as “the state in which two surfaces are held together by interfacial forces which may consist of valence forces or interlocking action, or both.” If we speak of adhesion as these interfacial forces, then we must abandon hopes of trying to measure adhesion. That is, we cannot measure these interfacial forces by means of mechanical tests. However, even if we could, knowledge of the magnitude of these forces would not necessarily mean anything in a practical sense, since “adhesive” failures have invariably proven to be cohesive.
Paper ID: STP37162S