Processes of dynamics of surface layers during low-amplitude fretting

A model of dynamic effect during low-amplitude oscillations of surfaces comparable with the preliminary displacement and the first acts of sleep under the oscillating tangential loading of the contact is developed. Solving a system of differential force balance equations has yielded the main characteristics of the process of the dynamics of a nominally stationary contact depending on the governing parameters of the system. Regularities of the friction characteristic at low sliding velocity are determined with allowance for the preliminary displacement phenomenon, the Stribeck effect, as well as the parameter of the plasticity and viscosity of friction. The model allows one tracing the evolution of relative displacements and slip velocities, calculating phase diagrams, as well as deriving the friction characteristic and real slip amplitudes typical of the mixed friction mode and low-amplitude fretting.