A molecular dynamics study of nanometric scale friction

Friction is an omnipresent phenomenon in all mechanical systems, inducing uncertainties and acting as a major disturbance in manufacturing technologies and in the field of the micro- and nanoelectromechanical systems (MEMS & NEMS). The effects of friction can generally be compensated in the macro- and mesoscale applications. Multiple concurrent effects of various atomic-scale phenomena in the asperity contacts hinder, however, the prospect of a satisfactory insight into the fundamental tribological behaviour in the micro- and nanoscales. An in-depth fundamental understanding of nanoscale frictional behaviour is, thus, of outmost technological importance. An approach using molecular dynamics (MD) simulations is, hence, proposed in this work to study the tribological behaviour in the nanoscale (atomic) contacts. Recent thorough scanning probe microscopy experimental measurements of nanoscale friction on various thin-film materials are thus used as benchmark for MD simulations, allowing to attain important insights into the dynamics of a sliding tip on an aluminium thin-film surface while varying the normal loads. A sound basis for future more complex models, which will include adhesive effects and oxide layers, is thus accomplished, creating the preconditions to deepen further the fundamental knowledge of important tribological phenomena.