An extended bearing area model and stickiness criterion for adhesive contact of layered materials

Covering a solid surface with a soft layer can significantly enhance adhesion; however, surface roughness can easily suppress it. Therefore, understanding the adhesive contact behavior of rough layered materials is of great importance. In this study, we present a closed-form solution for the adhesive contact between a rigid rough surface and a layered elastic half-space. As a preliminary step, we establish the relationship between interfacial separation and normal load in the absence of adhesion, based on Persson’s contact theory. Building upon this, an extended Bearing Area Model (BAM) is developed to account for adhesive interactions. Furthermore, a new stickiness criterion is proposed and compared with the Persson-Tosatti criterion. The proposed framework provides theoretical guidance for the design and application of rough layered materials in adhesion-critical systems.