Effects of self-affine surface roughness on the adhesion of metal-polymer interfaces

This paper concentrates on a theoretical examination of the influence of roughness on the adhesive properties along metal-polymer interfaces. An algorithm has been designed to generate a self-affine surface roughness. It has been used to examine influence of the Hurst exponent on the interface strength during a pull-off test of metal-polymer laminates. The generated surfaces are implemented in a cohesive zone model representing the interface between a coated steel and polyethylene terephthalate (PET). From the model it can be concluded that a small increase in surface area is linear with the interface strength. This relation does not hold when the increase in surface area becomes larger than 150%. The deviation from the linear relationship increases with smaller Young's moduli. This is caused by the reduced elastic energy storage in the polymer when local surface characteristics become more important. (c) 2005 Springer Science + Business Media, Inc.