title: Loading-unloading hysteresis loop of randomly rough adhesive contacts.
abstract: We investigate the loading and unloading behavior of soft solids in adhesive contact with randomly rough profiles. The roughness is assumed to be described by a self-affine fractal on a limited range of wave vectors. A spectral method is exploited to generate such randomly rough surfaces. The results are statistically averaged, and the calculated contact area and applied load are shown as a function of the penetration, for loading and unloading conditions. We found that the combination of adhesion forces and roughness leads to a hysteresis loading-unloading loop. This shows that energy can be lost simply as a consequence of roughness and van der Waals forces, as in this case a large number of local energy minima exist and the system may be trapped in metastable states. We numerically quantify the hysteretic loss and assess the influence of the surface statistical properties and the energy of adhesion on the hysteresis process.
authors.affiliation: Department of Mechanics, Mathematics and Management, Politecnico di Bari, v.le Japigia 182, I-70126 Bari, Italy.|CNR, Institute for Photonics and Nanotechnologies U.O.S. Bari, Physics Department M. Merlin, via Amendola 173, I-70126 Bari, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Carbone
authors.affiliation: Scuola di Ingegneria, Università degli Studi della Basilicata, Campus di Macchia Romana, Via dell'Ateneo Lucano 10, I-85100 Potenza, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Pierro
authors.affiliation: Department of Mechanics, Mathematics and Management, Politecnico di Bari, v.le Japigia 182, I-70126 Bari, Italy.
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Recchia