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"Nonlinear Physics Seminar: Friction is fracture: frustrated cracks and slippery surfaces" | The Racah Institute of Physics

"Nonlinear Physics Seminar: Friction is fracture: frustrated cracks and slippery surfaces"

Date: 
Wed, 28/10/201512:00-13:30
Location: 
Danciger B building, Seminar room
Lecturer: Dr. Elsa Bayart
Affiliation: Racah Institute of Physics
The Hebrew University of Jerusalem
Abstract:
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.