Tribological behavior of fullerene-like hydrogenated carbon films at different contact loads

• 1、 National Engineering Research Center for Technology & Equipment of Green Coatings, Lanzhou Jiaotong University, Lanzhou 730070, China
• 2、State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China

Abstract：The friction and wear behaviors of fullerene-like hydrogenated carbon films sliding against Si3N4 balls were investigated at different contact loads from 1 to 20 N on a reciprocating sliding tribometer in the air. It was found that the films exhibited non-Amontonian friction behavior, with the friction coefficient decreasing with an increase in contact load. At the 1 N contact load, the friction coefficient was ~0.112, whereas at the 20 N load it decreased to a super-low value (~0009). The main mechanism responsible for low friction and wear under varying contact stresses was governed by the third bodies (also known as transfer films) that form and reside in the sliding interface. It was argued that the tribochemistry of the transfer films was responsible for the observed friction behavior: hydrogenated carbon-containing species were responsible for very low friction coefficient, wear, and interfacial shear stress. The link between interfacial tribochemistry and the pressure-induced transfer film shear strength provided the chemical-mechanical mechanism for explaining friction and wear differences in varying environments.

Keywords： carbon films friction wear tribochemical interaction