An interpretation of the failure paths of roughened metal/polymer interfaces

Roughening of metal surfaces enhances the adhesion strength of metal to polymer by mechanical interlocking and this often produces cohesive failure. In a previous work [1], an adhesion study on a roughened metal-polymer system was carried out, and the correlation between adhesion strength and failure path was investigated. In the present work, the correlation between failure path and microstructure of metal surfaces before molding was studied. The results showed that the variation in failure path could be explained by introducing a simple adhesion model developed from the theory of the fiber reinforcement of composite materials. It is believed that this model can be extended to other similarly roughened metal-polymer systems.