The method of electrospark machining has proven itself well in the technology of repair and restoration of parts. The operational properties of coatings obtained by this method depend on the microstructure, chemical and phase composition of the electrode materials. A significant improvement in operational properties, for example, wear resistance, is achieved by the formation of nanostructured coatings using electrodes with a certain content of alloying nanomaterials. It is possible to obtain such materials at the lowest cost by electro-erosion dispersion of machine-building waste. This article discusses the electrodes obtained by sintering bronze powder obtained by the method of electroerosive dispersion. Such materials are new for the process of electrospark machining; therefore, it is important to study and select the optimal application modes, since a qualitative characteristic of the process is the indicator of the transfer of the electrode material to the part, which depends on the processing modes and installation parameters. The aim of the study is to select the modes of the installation for electrospark treatment for optimal deposition of the material, as well as to study the degree of coating increment during electrospark treatment. Coating was carried out using an installation for electrospark treatment mod. «Westron» type AI-007, electrode material was obtained by the technology of spark plasma sintering of bronze powder, surfacing was carried out on steel samples 14 × 14 × 40 mm in size, the work also used an Acculab ALC-210d4 analytical balance and an MG micrometer Н25 GOST 6507-90. All coatings were applied to samples with an equal area in three layers under different processing conditions. After that, the increment in the thickness and mass of the electrode material on the sample surface was measured. Based on the results of the work, formulas were obtained and graphs were built. The most optimal mode of coating with an electrode made of sintered bronze obtained from machine-building waste by the method of electroerosive dispersion was determined, which proves the consistency of this method of obtaining electrode materials.

The high cost of metal powder materials and the energy consumption of the methods involved in their production have led to an increase in the cost of technologies for the restoration and hardening of parts. One method of solving this problem is the recycling of powders. A promising method for processing the waste from machine-building industries, including those utilizing non-ferrous metals and alloys, is electroerosive dispersion. Metallic powders from secondary raw materials obtained in this manner have good physical and mechanical properties, and their cost is two to three times less than the cost of industrial ones. However, the tribotechnical properties of the secondary powders of non-ferrous metals and their use in technologies for the restoration and hardening of parts are still poorly understood. This paper presents a comparative analysis of the tribotechnical properties of coatings obtained via an electric spark treatment with electrodes composed of bronze CuAl9Fe3 (CuAl8Fe3) (in the state of delivery), and coatings of sintered secondary bronze obtained via the method of electroerosive dispersion followed by spark plasma sintering. The results of the comparative tribotechnical tests under the conditions of dry friction showed that the complex indicator of wear resistance—the wear factor (F)—under dry friction conditions, for mates after an electrospark coating method with sintered secondary bronze, was 1.94 less than for mates with a CuAl9Fe3 (CuAl8Fe3) coating. This confirmed the high tribotechnical properties and the effectiveness of using cheap secondary bronze in repair production in technologies for restoring and strengthening worn parts of machines operating under dry friction conditions.

Introduction. To keep automobiles and tractors in operation conditions, it is necessary to restore the inner cylindrical surfaces of the friction pair parts. This is the most laborintensive activity. The method of electroplated contact deposition of composite coatings, based on elastic plastic deformation of formed layers, is used for repairing surfaces. To use this method it is necessary to determine the values of the elasticity modulus, on which the wear resistance of tribocouplings depends. Materials and Methods. For the study, cylindrical samples made of 30 HGSA and 30 HGSNA steels were used. Electrolyte containing 200–250 g/l chromium oxide, 2.0–2.5 g/l sulfuric acid, and distilled water was used for electroplating the coatings. When calculating the stress-strain state, the apparatus of continuum mechanics was used. Results. The dependence of the coating pliability as a function of the parameters of individual elementary layers is determined. When the multilayer coating of three types (orthogonal-reinforced, cross-reinforced and quasi-isotropic) is applied, its structure does not depend on the angles of kinematic tool movement on the inner cylindrical surface of the part. For each type of coatings, the way to determine the constant stiffness coefficients of the layers is specified. The dependences for calculating the elasticity modulus of the applied material are derived from the values of the stiffness coefficients. Discussion and Conclusion. In determining the modulus of elasticity of multilayered composite coatings, the calculation is made for the individual layers by passing to the convective coordinates, which is in complete agreement with the Lagrange point of view on the study of the motion of a continuous medium. The results obtained are of practical significance in the selection of the coating material to be applied for the restoration of internal cylindrical surfaces.

The article presents the results of comparative accelerated bench tests for production capacity, carrying capacity and wear resistance of materials: CT textile, Rusar and Oxafen textile. These materials are proposed for the manufacture of vacuum pump blades used in animal husbandry complexes for milking machines. From the vacuum pump depends on the performance of the milking machine, its reliability and noise level. In turn, the reliability of the pump is largely determined by the wear resistance of its blades. Therefore, the problem of choosing a lightweight, durable and wearresistant material for the blades is crucial in their design and production. The study of the wear process under friction is associated with the need to reduce losses caused by the wear process itself. As well as with the development of effective methods for predicting the durability of friction units, ensuring their reliable operation, especially under extreme conditions. Innovative development of materials based on polymer resins with the addition of carbon, glass, fabric and other reinforcing fibers have already found wide application in aircraft manufacturing, shipbuilding, construction, and electrical engineering. Such materials have high strength and low weight, which explains the interest in their use in the production, strengthening and repair of agricultural machinery parts. The research results presented in the article provide a comparative assessment of layered plastics based on polymeric binders with the addition of reinforcing threads that have unique properties: they have high physical and mechanical properties, are resistant to long-term variable loads, to wear.

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