Development of One-dimensional Microslip Friction Model and Determination of Boundary Between Stick and Slip Regions

Friction is a complex phenomenon which arises due to relative motion between preloaded contact interfaces. One of the most important issues in modeling friction is the debate over the way to consider a partial slip effects in the contact interface model. In this paper, a one-dimensional micro-slip model has been studied analytically. At first, governing equations of motion of a vibrating system are obtained, which is supported by a frictional contact and excited by a single harmonic displacement. Then, steady state response of a system is determined analytically. Objective functions are defined as criteria which depict a transition from stick region to slip region. Afterwards, minimization of objective functions is implemented based on steady state analytical solution and with the aid of genetic algorithm, and so, the arrangement and the lengths of segments corresponding to stick and slip regions are determined. Despite of past researches in this field, by using the proposed model, there remains no need to guess the number and locations of stickslip regions, before the system analysis. Also in this research, The boundaries between stick and slip regions for two kind of normal load distribution have been calculated by the proposed model, and then verified by the results obtained from finite element modeling.