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arXiv · 1501.00360

Critical length limiting super-low friction

Ming Ma·Andrea Benassi·Andrea Vanossi·Michael Urbakh
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Abstract

Since the demonstration of super-low friction (superlubricity) in graphite at nanoscale, one of the main challenges in the field of nano- and micro-mechanics was to scale this phenomenon up. A key question to be addressed is to what extent superlubricity could persist, and what mechanisms could lead to its failure. Here, using an edge-driven Frenkel-Kontorova model, we establish a connection between the critical length above which superlubricity disappears and both intrinsic material properties and experimental parameters. A striking boost in dissipated energy with chain length emerges abruptly due to a high-friction stick-slip mechanism caused by deformation of the slider leading to a local commensuration with the substrate lattice. We derived a parameter-free analytical model for the critical length that is in excellent agreement with our numerical simulations. Our results provide a new perspective on friction and nano-manipulation and can serve as a theoretical basis for designing nano-devices with super-low friction, such as carbon nanotubes.

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Ming Ma, Andrea Benassi, Andrea Vanossi, Michael Urbakh. 2015-01-02. Critical length limiting super-low friction. https://doi.org/10.1103/physrevlett.114.055501

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