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arXiv · 0804.3909

Nonlinear hysteretic behavior of a confined sliding layer

N. Manini·G. E. Santoro·E. Tosatti·A. Vanossi
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Abstract

A nonlinear model representing the tribological problem of a thin solid lubricant layer between two sliding periodic surfaces is used to analyze the phenomenon of hysteresis at pinning/depinning around a moving state rather than around a statically pinned state. The cycling of an external driving force F_ext is used as a simple means to destroy and then to recover the dynamically pinned state previously discovered for the lubricant center-of-mass velocity. De-pinning to a quasi-freely sliding state occurs either directly, with a single jump, or through a sequence of discontinuous transitions. The intermediate sliding steps are reminiscent of phase-locked states and stick-slip motion in static friction, and can be interpreted in terms of the appearance of travelling density defects in an otherwise regular arrangement of kinks. Re-pinning occurs more smoothly, through the successive disappearance of different travelling defects. The resulting bistability and multistability regions may also be explored by varying mechanical parameters other than F_ext, e.g. the sliding velocity or the corrugation amplitude of the sliders.

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N. Manini, G. E. Santoro, E. Tosatti, A. Vanossi. 2008-04-24. Nonlinear hysteretic behavior of a confined sliding layer. https://doi.org/10.1088/0953-8984%2F20%2F22%2F224020

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