ADHESION OF A RIGID PUNCH TO A THIN ELASTIC LAYER

Adhesion between a rigid flat cylindrical punch and an elastic layer h as been investigated. FE analysis was employed to determine the layer stiffness. Linear elastic fracture mechanics was then used to determin e the energy release rate, G(a), per unit of bonded area for a circula r debond propagating inwards from the edge of the punch. The calculati ons showed a strong effect of Poisson's ratio for thin layers, small d epartures from complete incompressibility causing large reductions in stiffness and hence in detachment force. Experiments were performed wi th an aluminum punch adhered to a rubber layer using a rubber-based ad hesive. The ratio of punch radius to layer thickness was varied over t he range 0.07 to 3.3. Detachment forces were measured and compared wit h calculated values. Reasonable agreement was obtained for thick layer s but not for thin ones, possibly because of a change in the mode of f ailure.