Ultra low friction of conductive carbon nanotube films and their structural evolution during sliding

Solid lubricating coatings with high conductivity are widely used in aerospace, tram and micro mechanical systems. In this study, a solid lubricating film with ultralow friction coefficient and good electrical conductivity was prepared using hydroxylated CNTs through electrophoretic deposition, and the structural evolutions when the CNT films act as lubricants are investigated in-depth. It was found that the electric resistance reduced significantly with the increase of the deposited CNT film thickness, and then it reached a saturation value of approximately 40 omega at the film thickness of 0.7 +/- 0.10 mu m deposited at 50 V. Moreover, the friction coefficient was reduced by 71% at the deposition voltage of 40 V compare to the single crystal silicon. It is worth noting that the original carbon nanotubes transformed into nano-scrolls under the action of friction shearing and heating. At the same time, this work provided new insights for the structure evolution of carbon nanotube films during the rubbing process.

Automated summary

In this study, a solid lubricating film with ultralow friction coefficient and good electrical conductivity was prepared using hydroxylated CNTs through electrophoretic deposition, and the structural evolution of CNT films acting as lubricants was investigated. It was found that the electric resistance decreased significantly with the increase of deposited CNT film thickness, and the friction coefficient was reduced as well.