A numerical model for the adhesive contact between a rigid sphere and an elastic multi-layered media

Phenomenons of adhesive contact are quite common in micro-electro-mechanical system devices, whose reliability is severely affected by the adhesive properties of contacting bodies. The Classical JKR model fails when the contacting body size decreases to nanoscale because of the assumption failures. This investigation reports a novel numerical model of adhesive contact between a rigid smooth sphere and an elastic multi-layered medium, in which the Hamaker summation method and Lennard-Jones intermolecular potential law are employed. Analytical expressions of adhesive contact pressure for multi-layered media are derived. The Newton-Raphson method and fast Fourier transform algorithm are introduced to enhance the computational efficiency. Further, the effectiveness of the present model is validated by comparison with results from published literature. Finally, parametric studies about the influences of layer properties, like elastic modulus, Dupre adhesion energy and layer thickness, on the adhesive mechanical behavior of multi-layered media are carried out. The analysis results are beneficial to the optimal design of an adhesive contact system to improve its comprehensive mechanical performance.