Contact area and maximum equivalent stress in elastic spherical contact with thin hard coating

A finite element analysis was used in order to investigate the elastic contact of a sphere with a thin hard coating compressed by a rigid flat. A proper normalization of the dimensional contact parameters, such as the contact area, load, interference and maximum equivalent von Mises stresses in the coating and in the substrate was used to obtain a universal model of the elastic contact. This model provides empirical relations between these contact parameters for a wide range of mechanical and geometrical properties, which are different from the classical Hertz solution for a homogeneous sphere compressed by a rigid flat. The model also introduces a new approach for calculating the limit of elasticity in the coated system. (C) 2015 Elsevier Ltd. All rights reserved.