Predicting instantaneous friction from friction damping coefficients in underdamped sliding

Friction accounts for nearly one-third of global energy consumption. While the coefficient of friction is widely used to quantify energy dissipation in sliding contacts, its strong dependence on sliding velocity limits its effectiveness in predicting instantaneous friction forces and friction-induced vibrations. To overcome this limitation, we present an experimental method based on atomic force microscope (AFM) for determining friction damping coefficients. These coefficients, derived from the torsional and vertical deflection oscillations of the AFM cantilever as it slides over a substrate, remain nearly constant and show minimal sensitivity to sliding velocity or normal load. Once established, they allow for accurate prediction of both time-averaged and instantaneous friction forces. Experimental validation over a broad range of velocities and loads confirms the robustness of this approach, underscoring its potential to advance dynamic friction modeling and vibration mitigation in tribological systems.