抄録
Hard coatings, which are used to protect surfaces that are subjected to contact loading, may fracture or delaminate from their substrates. The probability of the extension of surface crack due to cylindrical indentation is analyzed. The coated half-space is loaded by a cylindrical indenter, which slides over the surface of the coating. Contact loading problems typically result in multiaxle and inhomogeneous stress fields near the contact surface. This behaviour which strongly affects the stress intensity factors is taken into account in the failure analysis. A suitable method is described for calculating the contact stress fields in coating and substrate. Edge cracks are selected to model the surface flaws. The coating is idealized as a brittle-elastic layer of uniform thickness, which is bonded to the surface of a half space. Method of linear elastic fracture mechanics are then used to calculate the loads to initiate fracture in the coating.
