COLL 60 |
| Roland Bennewitz1, Enrico Gnecco2, Anisoara Socoliuc2, Urs Wyder2, and Ernst Meyer2. (1) Department of Physics, McGill University, Ernest Rutherford Physics Building, 3600 rue University, Montreal, QC H3A 2T8, Canada, (2) Institute of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland |
| The energy dissipation in a sliding contact can be measured with a friction force microscope by determining the mean lateral force acting on the contact. At the same time, the lateral force exhibits atomic-scale fluctuations, which reflect transitions in the structure of the contact area. Experimentally, we find a predicted transition from stick-slip-type sliding to continuous sliding, and a decrease of the mean lateral force, which approaches zero at the point where the stick-slip smoothes out. We will discuss the results in terms of a Tomlinson model, including dynamical aspects of the slip process. We will also report on experiments regarding wear on atomic scale. Surface material was removed layer by layer, and the re-crystallized debris imaged by the same tip. The formation of ripple structures around such scratches was found to be the result of an interplay between modulated lateral forces and the developing topography. |
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Friction, Lubrication, and Adhesion in Micro- and Nano-Scale Devices
2:00 PM-5:00 PM, Sunday, March 28, 2004 Marriott -- Orange County 5, Oral
Division of Colloid and Surface Chemistry |