Analysis of the influence of the change in the geometric parameters of the micro roughness of the mobile connected surfaces with the adsorption layer of pairs on their convergence

Problem. In connection with the trend of increasing the volume of road construction work, there is a need to ensure increased reliability of road machines. Most earthmoving machines operate under high loads. Severe working conditions and the dynamic, vibrational nature of the load of these machines reduce the reliability and operating time of their hydraulic drives. The complexity of friction and wear processes in the joints of real machine parts does not yet allow us to describe them quantitatively with sufficient accuracy. However, for engineering calculations of the influence of the roughness parameters of friction surfaces on the intensity of their wear, already known dependencies can be used that establish the relationship between the wear intensity and the friction parameters of the surfaces. There are different models for the formation of conditions for the development of the process of wear of the surfaces of movable joints. One of the issues of modeling the process of wear of the surfaces of mobile joints is the question of the influence of the adsorption layer of surfactant on the stress state at the basis of their microroughness. Goal. The goal of the studies was to determine the change in the convergence of microprotrusions of mating surfaces with a change in the radius of the tops of microprotrusions in the presence of a surfactant adsorption layer on them. Methodology. Solution of the problems set involved the formation of a model of the process of contact of individual microprotrusions of rough surfaces coated with a surfactant adsorption layer, and its application to determine the dependence in the change in the approach of microprotrusions with a change of the radius of their top and the thickness of the surfactant adsorption layer on them. Results. The dependence of the amount of convergence of micro-uniformities in the coupling on the geometry of micro-uniformities and the thickness of the adsorbed surfactant layer was obtained. The performed calculation of the convergence of micro-uniformities taking into account the thickness of the surfactant adsorption layer showed that under these initial conditions, the convergence of the surfaces of micro-uniformities can be up to 19% relative to the radius of their tops. Originality. A model of the process of interaction of individual microroughnesses of rough surfaces of movable tribocoupling is proposed, which allows one to analyze the influence of the load in contact, the geometrical parameters of the contacting microprotrusions, and the parameters characterizing the surfactant adsorption layer on the approach value of contacting microprotrusions. Practical value. The use of the proposed mathematical model allows predicting the result of the process of interaction of rough friction surfaces in the presence of a lubricating material, based on the convergence of the friction surfaces.