Atomic Scale Friction in the Function of Modified Eyring Activation Energies

Abstract

At microscale, friction is better understood fundamentally through hydrodynamic and elastohydrodynamic lubrication. However, the mechanisms governing friction at nanoscale remains a subject of interest. With the emergence of small-scale devices such as Microelectromechanical Systems (MEMS) and Nanoelectromechanical Systems (NEMS), there is a need to improve on the fundamental understanding of friction at diminishing gaps. Therefore, the paper investigates the friction of a simple fluid (n-hexadecane 99%) using an atomic force microscope. The measurements are interpreted using modified Eyring’s thermal activation energy approach in order to examine the effect of molecular solvation at the assumed smooth summit of asperities. It is found out that solvation for a sliding contact could be observed through the shear stress activation volume due to generated thermal energy, which indicates the movement of the fluid molecules into and out of the contact.