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The thermodynamic analysis of the interaction of composite powder alloys of the Co-TiC system with air is carried out. The main regularities of their oxidation are established. The mutual influence of the content of chromium and titanium carbide on the quantitative composition of oxidation products is shown. Based on the analytical studies, the dependence of the quantitative and qualitative composition of the products of interaction with air of powdered alloys of the Co-TiC system on the ratio of their components was determined. The formation of protective layers can be predicted, and their formation can be controlled by selecting appropriate alloying elements and strengthening phases by thermodynamic analysis. The general laws of oxidation of powdered composite alloys of the Co-TiC system have been established. The influence of chromium content in the material on the composition and properties of oxide layers is shown. It was found that at a high chromium content in the matrix (more than 25% by volume), the brittleness of the oxide layer increases, which will lead to its intensive wear. [ABSTRACT FROM AUTHOR]

The issues of ensuring the durability and reliability of equipment, increasing wear resistance and expanding the range of operation of friction pairs in extreme operating conditions require solutions related to innovative technologies for the formation of wearresistant surfaces that can significantly increase the efficiency of using hardening methods, creating new ones and improving existing ones. A brief review of the combined methods of engineering contact surfaces of tribological systems is carried out. The perspective of using this direction to expand the range of use of discrete protective structures, namely in the conditions of fretting, fretting fatigue, and limit friction, is shown. [ABSTRACT FROM AUTHOR]

Theoretical and experimental studies of the energy load of a disc-pad brake of a vehicle made it possible to propose a method for determining the components of generated electric currents in metal-polymer friction pairs, based on experimental and calculated data, which is implemented in five stages, at each of which the total electric currents: thermal; the current that arises due to the friction of sliding and contact-interacting macro sections of the surfaces; current arising due to sliding friction, formed by the movement of charged mass transfer particles; the current caused by sorption-desorption processes in the near-surface layers of the lining, which are at a temperature higher than the permissible for its materials, as well as their direction. Determine the total wear during the braking cycle of the friction disc treadmill as the sum of losses due to its oxidation (corrosion) with the involvement of mechanical wear. The components (mechanical, electrical, thermal) of the friction power and their calculated values were determined with the help of the obtained dependencies. Based on the found value of the energy balance of the brake friction unit, the volume intensity of wear of the working surface of the lining was determined based on the obtained dependence with the transition to the dependence of the actual resource, taking into account the width and permissible thickness of the wear of the lining. The projected service life of the pad is achieved due to its working area and length, as well as the specified radius of the microprotrusions of the friction track of the disc. This method made it possible to increase the resource of the friction pad by 1.25 times under different operational parameters of the disc-pad brake of the vehicle. [ABSTRACT FROM AUTHOR]

The structure, phase and chemical composition, microhardness, and microbrittleness of the surface zones of P6M5 steel after chemical and thermal treatment: nitriding followed by titanium and chromium plating are considered. Metallographic and micro-X-ray spectral analyzes of wear surfaces of P6M5 steel with different types of coating were carried out. It is shown the dependence of physical and mechanical properties of complex coatings and discrete laser treatment on wear-resistance. The analysis of the obtained data showed that azochromic coatings with additional strengthening by laser treatment of steel, which serves as a substrate for coatings, increase its performance in extreme operating conditions, excluding its crushing, chipping and peeling. [ABSTRACT FROM AUTHOR]

The article considers the efficiency of applying electric spark coatings with the aim of studying the effective influence on the tribological properties of eutectic alloys. Friction and wear tests of electrospark coatings made of the developed eutectic alloy on a steel substrate were performed. In order to compare the effectiveness of the influence on the tribotechnical properties of eutectic alloys, both the coatings in the initial state and the coatings annealed under two different modes were tested. Based on the results of the study of the chemical composition of the films formed in the process of friction, regularities were established by qualitative assessment. The dependences of tribotechnical properties for the initial and heat-treated coatings were determined. These studies indicate the feasibility of using electrospark coatings for different friction conditions. [ABSTRACT FROM AUTHOR]

An analysis of the existing anti-friction materials used in the friction units of the gas pumping unit as bearing liners was carried out. Taking into account the shortcomings, a new material is proposed in the work, which will be cheaper and have better operational properties. It was considered the characteristics of effect of alloying of metallic die on the processes of generation of tribotechnical characteristics of alloys and coatings on the basis of iron with refractory carbides and borides. It was resulted the technology of alloying of die of eutectic alloys as VTN by the components of bronze Sn-Zn-Pb 5-5-5. It was designed a wearproof antifriction eutectic alloy on the basis of iron for the welding of surfaces of bearing shells, presented it's tribotechnical characteristics and estimated the perspective of using the alloy for shells of sleeve bearings of gas turbine units in place of babbits. [ABSTRACT FROM AUTHOR]

Copyright of Problems of Friction & Wear is the property of National Aviation University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Problems of Friction & Wear is the property of National Aviation University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work is a comprehensive study of the structure and properties of plasma eutectic coatings after thermal cyclization. This kind of treatment significantly increases the adhesive-cohesive strength of coatings. According to the results of the conducted research, the resistance against the operation of two-layer coatings in the whole temperature range is higher than for single-layer ones. This effect is achieved by the increase in adhesion properties, a decrease in the hardness gradient along the depth of the coating, and the increase in the coating's thermal stability due to the barrier properties of the doped boride layer. By controlling the size of the dispersed crystals of the penetration phases and at the same time the state of the metal matrix, it is possible to select the TCO modes in which the coatings receive optimal tribotechnical properties. [ABSTRACT FROM AUTHOR]

Copyright of Problems of Friction & Wear is the property of National Aviation University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Problems of Friction & Wear is the property of National Aviation University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

These ways оf improving the quality of such coatings by melting coating and thin surface layer or base their repeated cyclic heating continuous laser radiation in the range of temperatures (T (As1) PL). In the first case the bonding strength of coating base reaches 400 - 430MPa, the second - in 4-5 times increases to 90-120MPa, while the original-15-20MPa. Laser thermal cycling are high performance, does not require the subsequent machining. [ABSTRACT FROM AUTHOR]

The structure, phase and chemical composition, microhardness of the surface bands are 12Х18N10T after chromoaluminizing chromoaluminizing. It is shown that the wear resistance stali 12Х18N10T in sliding friction without lubrication with protective coatings increases by 1.5-5.6 times compared with the original. [ABSTRACT FROM AUTHOR]

The paper focuses on possibility to form coatings on the surface by method of rapid crystallisation, what will give mach benefits at their future application. It was investigated the process of deposition of wear resistant eutectic coatings to the internal surface of cylindrical elements with heating by high frequency current. We analysed the process of chemical and physical phenomena during crystallisation and forming of their structure. The resultant coating with high hardness has a columnar structure, good adhesion to the surface and promising wear resistance. [ABSTRACT FROM AUTHOR]

It was considered the peculiarities of prior laser treatment influence on the structure and properties of nitrided layers on steel surface. The general regularities of influence of laser beam parameters and the pattern of treatment on contact fatigue and tribological properties of the coatings. [ABSTRACT FROM AUTHOR]

The wear behavior of steel 12X18H9T was investigated of temperature range 20 - 800°C under various normal load and sliding speed. It was found that low near resistance of the steel is due to its homogeneous structure, loss of strength at high temperature and its natural tendency to intensive oxidation in triboactivated condition. [ABSTRACT FROM AUTHOR]

The tribological system with diphasic heterogeneous alloy 1Х18Н9Т-ТіВ2 have been investigated. It is set that tribotechnical descriptions depend on properties of self-generated in the contact of tribostructures. Tribostructure arise up as a result a multy stage synthesis, the most favorable conditions for their forming and functioning are eutectic compositions in the highly dispersion state. [ABSTRACT FROM AUTHOR]