On the effect of the height distribution function in adhesion of non Gaussian random rough surfaces, and a simple analytical model (BAM)

Abstract

Two apparently very different theories of adhesion of rough surfaces called BAM (bearing-area-model), and that of Persson–Tosatti lead to similar predictions concerning the stickiness of Gaussian surfaces: the role of roughness is mainly governed by the low wavevector content of the PSD. Here, we study the adhesion of non-Gaussian surfaces by means of a DMT-based simplified BEM (Boundary-Element-Method), and report a clear difference in the adhesion and stickiness of surfaces with different height distribution function. We then obtain analytical equations for a generalized BAM model. Results of the extended BAM theory compare reasonably well with numerical BEM-DMT predictions. We also notice that any theory based on the surface energy, would show instead insensitivity to height distribution.