Allgemeines Physikalisches Kolloquium im Sommersemester 2010
Ort:    48149 Münster, Wilhelm-Klemm-Str. 10, IG I, HS 2,
Zeit:    Donnerstag, 10.06.2010 16:00 Uhr c.t.
Kolloquiums-Kaffee ab 15:45 Uhr vor dem Hörsaal

Mechanismen der Reibung zwischen Festkörpern: Von geometrischer Verzahnung über Falten und spontanem Symmetriebruch bis hin zur Chemie
Prof. Dr. Martin Müser, Universität Saarbrücken

Solidfriction tends to change with velocity rather slowly, i.e., significantly less than linearly with velocity. It has long been recognized that the origin for this deviation from linear response theory must be due to microscopic hystereses or instabilities. In particular Prandtl showed more than 80 years ago in a simple albeit generic model system, why Coulomb friction is indicative for a system to be out of thermal equilibrium and how thermal noise reduces friction. The precise nature of the instabilities for specific systems is however not always clear. In my talk I will review some of recent advances made in identifying relevant mechanisms from chemical bond breaking to instabilities in boundary lubricants and the friction of wrinkles. Attention will also payed to recent experiments on superlubric contacts, in which instabilities are suppressed.