Friction is fracture : frustrated cracks and slippery surfaces
Orateur : Elsa Bayart
The Hebrew University of Jerusalem, Israel
Résumé : The transition from static to sliding friction is mediated by interfacial shear cracks. These cracks break the solid contacts that form rough frictional interfaces and are quantitatively described in term of fracture mechanics. First, we will focus on arrested frictional ruptures that serve as precursors to sliding motion. We will show that fracture mechanics describe the spontaneous arrest of these precursory ruptures. This result shed light on the actively debated question in seismology of the selection of an earthquake’s magnitude and arrest. Then, we will show surprising results about frictional interfaces coated by thin lubricant films. Even though the frictional strength of the system is reduced by the lubricant, the fracture energy (the amount of energy dissipated per unit area) is an order of magnitude higher than in the case of dry friction.
Date et lieu : le Mardi 15 septembre 2015 à 11h00, locaux IRPHE