The main defect that occurs when using plows consists in the abrasive wear of ploughshares, whose highest wear level is observed in the toe part of a ploughshare. When restoring worn plowshares in order to increase their service life to a significant extent, it is worthwhile to use technical ceramics. A plowshare with soldered cermet plates has been chosen as the object for investigations. The proposed investigation methodology has involved the testing of plate adhesion, as well as bench and operational testing of experimental plowshares in comparison with serial ones. It has been established that the proposed type of joints between cermet plates and ploughshare has a high reliability level and can withstand a 3.8 to 4.9-fold excess with respect to design loads. As a result of the studies, a new resource-saving technology has been developed for the restoration and hardening of ploughshares by means of soldering with the use of a hydrogen-oxygen flame, which makes it possible to provide a 2 to 3-fold increase in the service life, as well as a 30–35

The analysis results of known methods for assessment of the resistance of steels and alloys to intercrystalline corrosion cracking are given. Based on the identified shortcomings, a new method of monitoring and diagnostics is proposed, which allows one to carry out an express-assessment of the tendency of steels and alloys to corrosion cracking (delayed destruction) under conditions of direct operation by analyzing the microhardness of their structural components.

A new design of cutting tool for plastic recycling is proposed, and the use of a water–polymer ultrajet as a diagnostic tool for studying the functional properties of a material is considered. The experimental results demonstrate that the developed knife design has broad prospects for practical application. These results are confirmed by a comparative analysis of various diagnostic methods and strength calculations of the tool.

Scanning electron microscopy and X-ray diffractometry are used to study the coating layer deposited on a CuSn10Pb10 bronze surface through electric spark machining with anode material having similar composition. X-ray studies of the phase composition indicate the presence of copper–tin phases (Cu, α-(Cu; Sn), Cu3Sn, ε-Cu3Sn, and Cu5,6Sn) and lead. The ratio of intensities of diffraction maxima illustrates the absence of a predominant growth (texture) orientation in the coating obtained through electric spark deposition. Scanning electron microscopy data prove that the surface coating layer contains melted areas, pores, spherical and oval inclusions, irregularly shaped particles, cracks, rounded pits, etc. The main reason behind melted areas deals with high temperatures developing between electrodes during an electric spark discharge. The appearance of surface fractures can be primarily associated with developing high thermal stresses and mechanical contacts between electrodes. Spherical/oval particles can develop due to interaction of liquid droplets with the cathode substrate surface. Irregularly shaped particles appear as a result of explosive emission from the edges of the erosion crater of the anode material.

An effective air-impact method for mechanochemical processes of activation of secondary raw materials in the production of building materials has been proposed. In order to increase the specific surface area of the binder and accelerate the strength gain of fast-hardening concrete mixtures, a model for calculating aeroactivators has been created on the basis of new technological equipment for activating cement, sand, and production waste. The proposed model establishes the dependence of the destruction rate of the contaminating shell of particles on the mechanical impact of the blows and physical–mechanical characteristics of the materials. To improve the performance characteristics of the aeroactivator, experimental studies have been carried out, the results of which made it possible to determine rational parameters of the improved installation and confirm the correctness of the developed design.

The coating on the surface of BrO10C10 bronze was studied by scanning electron microscopy and X-ray diffractometry. It was obtained by electrospark processing with an anode material with a composition similar to that of the substrate. X-ray studies of the phase composition revealed the presence of phases of the “copper – tin” system (Cu, α-(Cu; Sn), Cu3Sn, ε-Cu3Sn and Cu5.6Sn) and lead. The incorporation of atmospheric elements and initial bronze components into lead leads to the formation of regions with a distorted crystal lattice. An increase in the energy of a single pulse of an electric spark discharge is accompanied by a decrease in the α-(Cu; Sn) phase and an increase in the content of ε-Cu3Sn and Cu5.6Sn. The ratio of intensities indicates the absence of a predominant orientation of growth (texture) in the electrospark coating. Scanning electron microscopy data indicate the presence of melted areas, pores, spherical and oval inclusions, irregularly shaped particles, cracks, rounded pits, etc. in the surface layer. The main reason for the presence of melted areas is high temperatures in the interelectrode region during an electric spark discharge. The appearance of surface cracks is primarily associated with the occurrence of high thermal stresses and interelectrode mechanical contact. The presence of spherical/oval particles is a consequence of the interaction of liquid droplets with the surface of the cathode substrate. Irregularly shaped particles appear as a result of explosive emission from the edges of the erosion crater of the anode material.

—The efficiency of application of a new technology for repairing hydraulic distributors with the restoration and strengthening of the worn surfaces of the life-determining joints of parts and increasing their wear resistance is evaluated. The hydraulic distributors repaired according to the proposed technology exhibit an increase in the average overhaul life under real operation by 1.24 times compared to the life in the pre-repair period of operation.

The main thermal and gasdynamic characteristics of a plasma jet, which influence the spraying of a wire or a powder, are considered. The existing theoretical concepts of the physical processes during the formation of plasma coatings are analyzed. The factors favoring to the best adhesion of a coating to a composite surface are established.

The statistical relationship between the porosity of plasma-sprayed metal coatings and the distance and angle of spraying, the granulometric composition of the powder, and the current strength of the technological process is presented. Mathematical design of experiment is used. An adequate regression equation, which makes it possible to control the porosity of the metal coating by changing the plasma spraying factors, has been experimentally obtained. The steepest ascent method is used to determine the following rational coating deposition conditions, under which the porosity of the metal coating is 15

This work is devoted to evaluation of the efficiency of a new technology for repairing gear pumps with the restoration of worn surfaces of resource-defining mates of parts and increasing their wear resistance. Hydraulic pumps repaired by the proposed technology showed an increase in the average overhaul life in conditions of real operation of 1.07 times as compared with the resource in the prerepair operation period.

This work is about improving the service life of process equipment for fabricating cardboard products. New engineering solutions for electrospark treatment are described which are designed for improving the endurance of cutting parts and restoring their worn surfaces.

The main defect that occurs when using plows is an abrasive wear of its ploughshares, the greatest wear of which is observed in the nose. When renestoring worn plowshares in order to significantly increase their service life, it is advisable to use technical ceramics. A plowshare with soldered ceramic-metal plates was chosen as the investigation object. The proposed investigation methodology included the control of plate adhesion, as well as bench and operational tests of experimental plowshares in comparison with serial ones. It has been established that the proposed type of connection «metal-ceramic plates−ploughshare» has high reliability and can withstand exceeding design loads by 3.8—4.9 times. As a result of the investigation, a new service- life-saving technology has been developed for the restoration and hardening of ploughshares by soldering using a hydrogen-oxygen flame, which allows one to increase the resource by 2-3 times, as well as reduce costs by 30−35% instead of purchasing new serial ploughshares due to using a cheap hydrogen-oxygen gas mixture.

Data on the estimation and selection of working gases for powder plasma build-up welding are reported. Being selected appropriately, these gases protect molten metal against oxidation and stabilize arcing. The industrial use of plasma methods with a properly selected gas medium makes it possible to cover machine parts and equipment components by wear-resistant coatings. Mobile equipment for plasma build-up welding based on a KamAZ motor truck has been designed, as applied to which the thermophysical behavior of hot hydrocarbons has been considered. Recommendations for its use and operation control are given.

Статья посвящена оценке эффективности новой технологии ремонта шестеренных насосов с восстановлением изношенных поверхностей ресурсоопределяющих сопряжений деталей и повышением их износостойкости. Отремонтированные по предложенной технологии гидронасосы показали увеличение среднего межремонтного ресурса в условиях реальной эксплуатации в 1.07 раза по сравнению с ресурсом в доремонтный период эксплуатации.

A new method for diagnosing functional thin-film coatings applied by ion-plasma deposition using arc installations is presented. It is shown that the methods of friction tests, although they provide quite comprehensive information about the functional properties of coatings, nevertheless, have a serious drawback associated with the duration of the testing process. Considering wide technological possibilities of methods of vacuum sputtering of coatings in terms of varying technological modes of their deposition and, accordingly, a significant number of options for properties and characteristics of samples, it seems relevant to have such methods for assessing the quality of the coating in the arsenal of a technologist that would be distinguished by efficiency, but at the same time, high reliability of the results. A method for ultrajet diagnostics of functional coatings is proposed, and the effectiveness of the results of its use is evaluated in accordance with the informative data of the "classical" friction test method (friction tests). This paper concludes that the proposed method is effective and has a wide potential for implementation in enterprises engaged in the production of instrumentation products, precision technological equipment, and machine tools.

Introduction. The bakery industry is an agricultural industry of high-level processing of raw materials focuses on the end-consumer. In the production of bakery products one of the operations of the technological process is performed by dough dividers of vacuumpiston type, whose service life is 30‒40% lower than the normative. The most promising method for restoration of worn parts of the suction mechanism is electrospark processing. When selecting the electrode material, it is important that they have not only low erosion resistance, but also high tribotechnical properties. Aim of the Article. The article deals with problem of selecting electric coatings to reduce wear of working surfaces of suction mechanism parts during repair of vacuum piston-type dough dividers. Materials and Methods. The analysis of the properties of electropark coatings was carried out by nondestructive testing methods using modern research equipment; the results were processed using the Compass-3D program. Results. There are determined the values of physical, mechanical, frictional and tribotechnical properties of electrospark coatings made of BrOS10-10 bronze and Kh15N60 alloy. The total wear rate for BrOS10-10 bronze coating was 8,3 ∙ 10‒12, and for Kh15N60 alloy 15 ∙ 10‒12. Discussion and Conclusion. Total wear rate on the friction machine of bronze coated samples is lower than that of basic friction pair in 1.4 times, and of alloy coated samples ‒ higher in 1.26 times. Adding of MODENGY solid-lubricant coating to the coating from the alloy reduces its abrasion ability by 3 times, and the total wear rate ‒ by 1.34 times in comparison with the base friction pair. The used calculation-experimental method showed low wear rate of electrospark coatings of bronze and alloy in relation to the material of parts of the suction mechanism of vacuum-piston-type dough dividing machines.

The physical (modulus of elasticity), mechanical (tensile strength), and frictional properties of the modified surface layer formed by a copper–phosphorus electrode on parts made of an AK5M7 aluminum alloy by electric spark treatment are studied. The results, which are necessary for a computational and experimental estimation of the wear intensity of the electric spark coating, are presented. Determination of the elastic modulus of the samples after the electric spark treatment was carried out by the method of instrumental indentation. A computational–experimental estimation of the wear intensity of the surfaces of the parts subjected to electric spark treatment for an elastic contact interaction and steady-state optimum roughness is performed. As a result of laboratory tests, the optimum tribotechnical parameters of the roller–block friction pair are found.

The results of a comprehensive assessment of the quality of coatings obtained by electrospark deposition technique are presented. The assessment was performed using modern measurement instruments and dedicated software packages to determine the parameters of micro- and macro-geometry of the coated surfaces. It has been established that the main criteria for assessing the thickness of electrospark coatings, used to restore and harden parts, are the minimum depth, as well as the maximum height and peak-to-valley distance of the profile. It has been proven that the optimal ratio between the length of the bearing friction surface that receives an external load and the length of the surface covered by lubricant is at least 80 % for tribotechnical friction couples, and at least 60 % for parts with hardened surface.

A review and analysis of the influence of electrospark treatment on the residual fatigue limit of parts as well as of the degree of influence of electrospark surfacing on the fatigue strength of automotive parts restored by electrospark treatment are given. We present rational technological regimes for electrospark coating deposition and rolling under plastic deformation of the surface of electrospark coatings used in the restoration of worn parts.