Mechanism of sliding friction on a film-terminated fibrillar interface.
We study the mechanism of sliding friction on a film-terminated fibrillar interface. It has been shown that static friction increases significantly with increasing spacing between fibrils, and with increasing rate of loading. However, surprisingly, the sliding friction remains substantially unaffected both by geometry and by the rate of loading. The presence of the thin terminal film is a controlling factor in determining the sliding friction. Experimentally, and by a simple model in which the indenter is held up by the tension in the thin film, we show how the indenter maintains a nearly constant contact area that is independent of the fibril spacing, resulting in constant sliding friction. By this mechanism, using the film-terminated structure, one can enhance the static friction without affecting the sliding behavior.
Department of Theoretical and Applied Mechanics, Cornell University, Ithaca, New York 14850, USA.
Lulin
L
Shen
Anand
A
Jagota
Chung-Yuen
CY
Hui
D000268:Adhesiveness; D000818:Animals; D001696:Biomechanical Phenomena; D004129:Dimethylpolysiloxanes / Q000737:chemistry; D004867:Equipment Design; D017276:Friction; D008422:Materials Testing; D008853:Microscopy / Q000379:methods; D008855:Microscopy, Electron, Scanning / Q000379:methods; D015233:Models, Statistical; D033081:Shear Strength; D013314:Stress, Mechanical; D013499:Surface Properties
D004129:Dimethylpolysiloxanes; C013830:baysilon