The role of capillary condensation of water in the nanoscale friction and wear properties of boron carbide films

Abstract

The influence of capillary condensation of water at the atomic force microscope tip and boron carbide film surface on the friction forces and wear of the films is studied by force microscopy. It is shown that friction and wear are strongly dependent on the humidity. At low humidity no wear at the film surface is verified, while at high humidities constant wear rates are measured. The results show that the wear mechanisms of amorphous boron carbide films are highly dependent on the environmental humidity. A wear model based on a film surface interaction with the air moisture induced by the dissipated energy at the microscope tip–surface interface while in relative motion is presented.