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Grinding is a finishing method to treat cylindrical surfaces with wear-resistant coatings, which is the micro-cutting of material with many grains that affect each other through the work surface. Since vibrations inevitably occur in the dynamic system when cutting, the accuracy of the shape of the surface obtained by grinding depends on the rigidity of the attachment of the tool and workpiece, as well as on the machining modes. An advanced stochastic model has been developed to study the dynamics of the grinding process. In the model, the machining process is depicted as micro-cutting with abrasive grains that are randomly distributed over the grinding wheel’s surface. The geometric parameters of the grains are also random. The simulation results in surface textures after machining, the distribution of cutting forces, and the dynamic deviations of the tool. Their spectral characteristics were constructed, which made it possible to test the influence of processing modes and technological system parameters on vibrations, which leads to a loss of processing quality.

Thermomechanical processes that accompany the processing of products made of structurally inhomogeneous materials are considered. The presence of stress concentrators in the surface layer of processed products in various types of heterogeneities of hereditary origin introduced in obtaining the workpiece and subsequent mechanical processing types are the leading indicators of working surfaces’ bearing capacity. The lack of research on the influence of inhomogeneities formed in the surface layer of products during mechanical processing on their functional properties and, in particular, on the bearing capacity or wear resistance, their optimization determines the relevance of constructing a mathematical model of defect formation in the physical and technical processing of structural elements using optimal criteria of fracture mechanics. A numerical and analytical model is developed to determine the thermomechanical state of structurally inhomogeneous materials containing inhomogeneities such as interfacial cracks and inclusions during mechanical processing. Based on this model, the crack resistance criterion's functional relationships with the technological control parameters are determined to ensure products' processed surfaces' quality characteristics.

Criteria for technological support of the quality of finishing the surface layer of cylinders with wear-resistant coatings using composite materials have been developed. In the process of finishing surfaces from wear-resistant materials there are defects on the production surfaces, which reduce the performance properties of products. After analyzing the causes of chips and cracks on the production surfaces, it has been identified that the occurrence of various defects is associated with thermal processes which accompanied the machining of products. During diamond abrasive machining, the structural influence of inhomogeneous surface layers of manufactured products leads to the appearance and development of various defects, such as cracks and chips. To determine the thermomechanical state of the working surface of the cylinder with a wear-resistant composite coating, which has partial delamination areas during the deposition process, an analytical model is available. On the basis of composite coatings Ni/Ni-TiO2, obtained by the method of electrochemical deposition, tribocorrosive studies were carried out. To ensure the required quality of wear-resistant coatings, rational treatment regimes of the respective groups were applied, as well as the instrument characteristics, taking into account hereditary defects when applying these coatings.

The possibilities of technical support of the quality of finishing processing of the cylinder working surfaces using coatings of wear-resistant materials are considered. For this, a design scheme is proposed for determining the stress-strain state of the cylinder-coating system. The influence of the processing regimes of a cylindrical group with a wear-resistant coating on its physical and mechanical characteristics is determined. The dependence of SIF on the delamination angle α and the roughness of the working area of the cylindrical surface Ra is presented. A design scheme is proposed for studying the mutual influence of exfoliation sections on stress intensity in a wear-resistant coating. The effect of particles on the wear resistance of the coating deposited by the electrochemical method is determined. A study of composite materials based on Ni/Ni-TiO2 in a scanning electron microscope. The calculated and experimental values of the ultimate dimensions of crack-like defects during grinding of wear-resistant coatings are considered. The dependence of crack formation on the surface of the surface processed by grinding under the cutting depth and tool characteristics is determined.

The possibilities of increasing the reliability and durability of a cylindrical group by technological methods, in particular, the use of coatings from wear-resistant materials on the working surfaces of cylinders are considered. Finishing methods of processing products with wear-resistant coatings lead to the formation of defects on the surfaces to be treated, which reduce the performance characteristics of these prod-ucts. An analysis of the causes of the formation and cracking on the surfaces of these products showed that the appearance ofthese defects is associated with the thermal processes accompanying the machining. In this case, it is necessary to take into account the influence of the structural heterogeneity of the workpiece layer on the mechanism of nucleation and development of defects such as cracks under the influ-ence of thermomechanical processes accompanying diamond-abrasive processing. An analytical model has been developed to determine the thermomechanical state of the working surface of a cylinder with a wear-resistant coating that has areas of partial delamination during appli-cation. Tribocorrosive studies of composite materials based on Ni/Ni-TiO2obtained by electrochemical deposition are carried out.