Loss of Adhesion of a Layer Bonded to an Elastic Half Space Caused by a Concentrated Contact

Abstract
A model is constructed to analyze the effects of a concentrated contact on a layer that is perfectly bonded to an elastic half space, except for a debond region, which is analyzed as a fractional interfacial crack. The crack is assumed not to open and the growth is governed by a mode II stress intensity factor that is retarded by interfacial friction. This model may be used to study the fracture of hard coatings at the asperity scale where the failure is caused by loss of adhesion of the interface. Two specific cases are considered: one in which the loading is by a point force and one in which the loading is by a finite size of contact about the size of the layer thickness.