Direct modelling of surface topography development in a micro-contact with the movable cellular automata method

Many aspects of wear are still far from understanding. The paper proposes theoretical approach exploring the mechanisms of friction and wear on the basis of combining micro- and macro-modelling. In a macroscopic phenomenological model processes of wear are considered as stochastic processes in the surface layers of contacting bodies, including spalling of wear microparticles, local stochastic transport due to plastic deformation as well as processes of nano-welding. We show that parameters of this model can be obtained as a result of direct simulation of a microscopic tribological contact. In the paper, the method of movable cellular automata is used for this aim. The results show a stochastic migration of a friction layer in the direction perpendicular to the sliding velocity. Estimation of the effective diffusion coefficient of the friction layer migration for different contacting materials, and construction of corresponding surface power spectra were done. The results help to identify the parameters of the macroscopic model and help to connect the micro- and macro-scales.