On the load-area relation in rough adhesive contacts. (April 2020)

• Record Type: Journal Article
• Authors: Khajeh Salehani, M.; van Dokkum, J.S.; Irani, N.; Nicola, L.
• Is Part Of: Tribology international. Volume 144(2020)
• Publication Date: 2020-04
• Subjects: Contact area and load -- Self-affine roughness -- Adhesion -- Cohesive-zone model; Tribology -- Periodicals; 621.89
• DOI: 10.1016/j.triboint.2019.106099
• Languages: English
• ISSNs: 0301-679X

Abstract

Abstract: It is well established that, at small loads, a linear relation exists between contact area and reduced pressure for elastic bodies with non-adhesive rough surfaces. In the case of adhesive contacts, however, there is not yet a general consensus on whether or not linearity still holds. In this work evidence is provided, through numerical simulations, that the relation is non-linear. The simulations here presented can accurately describe contact between self-affine adhesive rough surfaces, since they rely on Green's function molecular dynamics to describe elastic deformation and on coupled phenomenological traction-separation laws for the interfacial interactions. The analysis is performed for two-dimensional compressible and incompressible bodies under plane strain conditions. Interfaces with various roughness parameters and work of adhesion are considered. Highlights: The effect of adhesion during contact is revealed through simulations. Adhesion is modelled through cohesive traction-separation laws. The reduced load-to-area relation is found to be non linear. Adhesion strongly depends on roughness, negligibly on compressibility.