Search

The purpose of the work is to study the influence of hafnium additives on the mechanical properties and thermal stability of particles at elevated temperature during heat treatment of aluminum alloys with a high magnesium content. Two modifications of 1570 alloy were chosen for the study: without hafnium content and with its addition of 0.5 % by weight. Both alloys were subjected to homogenizing annealing at a temperature of 440 °C with different exposure modes, which ranged from 2 to 100 h. Microhardness was studied for various heat treatment modes, and the fine microstructure was studied as well using transmission microscopy. As a result, it was possible to identify that during annealing at a short exposure time (2–8 h), the alloy with the hafnium addition has higher microhardness values exceeding those of 1570 alloy by an average of 20 HV units. This is associated with the fact that in 1570 alloy with hafnium additives, during heat treatment, the number of precipitated particles increases while their average size decreases compared to the base alloy. At the same time, in 1570 alloy without hafnium content, when annealed at a temperature of 440 °C, there is no increase in microhardness. This is caused by the fact that in 1570 alloy without hafnium content, when cooled after casting, discontinuous decomposition occurs, which resulted in the fact that most of the scandium precipitates from the supersaturated solid solution in the form of dispersoids. This phenomenon is not observed in the alloy with hafnium additives, which indicates its ability to stop discontinuous decomposition during cooling the ingot after casting.

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics 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.)

The paper proposes and experimentally tests a new method of welding aluminum alloys with simultaneous magnetic‑pulse treatment (MPT) of the liquid and solidifying metal of the welding pool. The results of investigations on semi‑automatic welding of AD1N aluminum alloy with MPT of the molten pool are presented. The influence of welding and magnetic‑pulse treatment modes on the structure and physico‑mechanical properties of the weld zones is investigated. The research data is presented in the range of discharge energy variation from 250 to 500 J and pulse numbers from 23–24. The results show that the influence of the pulsed magnetic field with discharge energy of 350 and 500 J leads to an increase in material hardness. It is shown that welding with simultaneous MPT in these modes results in structure refinement and the formation of a textured zone with elongated grains at the border with the heat‑affected zone.

The article presents the methodology and results of the study of the effect of ultrasonic treatment of the melt of deformable aluminum alloys during crystallization on the structure and properties of the formed ingots: the dependence of the grain score, porosity, size and distribution of inclusions of intermetallides on the amplitude of ultrasound radiation and the frequency of vibrations, as well as the distance to the waveguide. In addition, data on the analysis of the transformation of iron‑containing phases (α‑AlFeSi and β‑AlFeSi) under the action of ultrasound and dissolution of titanium waveguides during ultrasonic treatment of aluminum melt are presented.

Friction stir processing is one of the modern methods of local modification of the surface of aluminum alloys in the solid-phase state, which provides the dispersion of structural components. In heat-hardened aluminum alloys with a matrix type structure, heat treatment following after friction stir processing can lead to abnormal grain growth in the stir zone. However, in alloys with the structure close to microduplex type, a fine-grained structure can be formed after friction stir processing and heat treatment. This work is aimed at evaluating the possibility of increasing the microstructure thermal stability of the AK4-1 (Al–Cu–Mg–Fe–Si–Ni) matrix-type aluminum alloy. For this purpose, AK12D (Al–Si–Cu–Ni–Mg) aluminum alloy with the structure close to microduplex type was locally mixed into the studied alloy by friction stir processing. Subsequent Т6 heat treatment was carried out according to the standard mode for the AK4-1 alloy. Studies showed that the stir zone had an elliptical shape with an onion-ring structure. This structure comprised alternating rings with different amounts and sizes of excess phases. At the same time, in the stir zone center, the width of rings and the average area of excess phases were larger compared to the stir zone periphery, where the width of rings and the average area of particles were smaller. The average area of excess phases in the rings with their higher content was smaller than in the rings with their lower content. This distribution of excess phases leads to the formation of a fine-grained microstructure, where the average size of grains depends on the interparticle distance in the α-Al solid solution.

The processing of salt slags in aluminum production in order to obtain a powder material with a high content of aluminum oxide phases and the results of thermodynamic assessment of the hydrolysis reactions of aluminum carbide and nitride during the hydraulic treatment of slags are discussed. It is reported that water‑soluble fluorine compounds, such as Na3AlF6, CaF2, MgF2, K2ZrF6 , in the composition of refining fluxes complicates the processing of aluminum slags, which involve leaching of salts by water. A rational solution seems to be the replacement of sparingly soluble salts in refining fluxes with sodium or potassium fluorides with a higher solubility in water. It is shown that the powder mixture obtained after hydraulic treatment of aluminum slag includes various forms of structural components in the form of films, shells, submicroand nanostructures of various morphologies with the participation of various types of nano‑components, in which the phases of non‑metallic compounds predominate, mainly ceramic substances and salts (corundum Al2O3, aluminum oxynitride Al2.85O3.45N0.55, aluminum nitride AlN, sodium chloride NaCl) and metallic aluminum. It is indicated that the possibility of forming eutectic mixtures of ceramic compounds of aluminum oxide and aluminum oxynitride, which are more fusible than pure oxides and nitrides, must be taken into account when developing salt slag recycling technologies in order to obtain ceramic powder materials with a high content of alumina phases.

Information about the volumes of castings production in various countries of the world is given. The situation with the castings production in the Republic of Belarus is considered in more detail. An outlook on the ways of further foundry production development is presented. Recommendations have been developed on the main areas of application of cast products in mechanical engineering.

The paper presents the results of studies on production of layered composite materials, based on aluminium and titanium alloys, by vacuum diffusion welding, with a broad range of specific weight values, which is achieved due to different layer ratio in each of the composites. Based on a layered composite material, a procedure was proposed for manufacture of three-layer honeycomb panels by vacuum diffusion welding. It is found that the average compressive strength of the three-layer panel with a filler from a layered composite material based on Al–Ti alloys is equal to 47.3 MPa, that is four times higher that the strength of similar honeycomb elements made from an aluminium alloy. It is shown that the layered material has higher thermal stability, compared to aluminium alloys. Sample annealing at the temperature of 700 °С for 30 min does not lead to their early destruction or loss of shape. [ABSTRACT FROM AUTHOR]

Improving the technology of diamond turning of aluminum alloys is of great importance for expanding the application areas of metal-optical products based on aluminum in aerospace technology. The aim of this work was to study the effect of surface inhomogeneities of the initial aluminum alloy substrates on their optical and mechanical characteristics and to determine ways of improving the quality of aluminum reflector mirrors manufactured using nanoscale single point diamond turning. The investigated reflector mirrors were made from AMg2 aluminum alloy. The optical surface treatment was carried out on a precision turning lathe with an air bearing spindle using a special diamond cutter with a blade radius of ≤ 0.05 μm. The analysis of the surface structure of the AMg2 alloy substrates was carried out by scanning electron microscopy / electron microprobe. The quality control of the surface treatment of the manufactured reflector mirrors was carried out by atomic force microscopy. The reflectivity and radiation resistance of these samples were also investigated.It is shown that an important problem in the manufacture of optical elements from aluminum alloys is the inhomogeneity of the structure of the initial material, associated with the presence of intermetallic inclusions. Heat treatment of the AMg2 alloy substrates at T ≥ 380 °C makes it possible to improve the quality of surface and the radiation resistance of aluminum mirrors both by removing mechanical stresses and by partially homogenizing the starting material. The optimum is heat treatment at the maximum allowable temperature for the AMg2 alloy T = 540 ºС, as a result of which there is a complete disappearance of intermetallic inclusions with an increased magnesium content. The use of high-temperature heat treatment of AMg2 alloy substrates allows, in comparison with unannealed samples, to reduce the surface roughness from 1.5 to 0.55 nm, to increase the reflectivity of mirrors at a wavelength of 1064 nm from 0.89 to 0.92, and to increase the laser damage threshold from 3.5 to 5 J / cm2.

Copyright of Refrigeration Engineering & Technology is the property of Odesa National University of Technology 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.)

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U 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.)

To create friction pairs operating in severe working conditions, composite materials are now increasingly used. Composite materials obtained with the use of casting technologies are of interest due to the possibility to manufacture wide range of compositions at low price compared to powder metallurgy. Despite the fact that many composite materials have been sufficiently studied, it is of interest to develop new areas of application and give them the properties required by the consumer. In the present work the composite materials on the basis of silumin reinforced with copper granules were considered. Attention was paid to the interaction between the matrix alloy and the reinforcing phase material as determining the properties of the composite material. The analysis of distribution of the basic alloying elements in volume of composite material and also in zones of the interphases interaction is carried out. The analysis of the possibility of obtaining a strong interphase zone of contact between the reinforcing component and the matrix material without significant dissolution of the reinforcing material is carried out.

The article describes the requirements for lubricants (release coatings) used in injection molding of aluminum alloys and polymeric materials. A methodology for conducting research to determine the tribotechnical characteristics of materials used in the development of the composition of a lubricant for injection molding aluminum alloys and polymer products, as well as the results of a study of tribotechnical characteristics (friction coefficient) are presented. It has been established that as materials used in the development of a multifunctional lubricant composition for casting aluminum alloys and polymer products, it is advisable to use a fraction of soap stock and fus after their preliminary sedimentation (at least 3 months). It is shown that the smallest value of the coefficient of friction at the time of indenter breaking on the surface of the steel disk was obtained using a fus. Moreover, the value of the coefficient of friction is 14–33% lower than the same indicator for other studied lubricants (petroleum jelly, PMS-100 and soap stock). It was found that in the mode of reciprocal movement of the indenter on the surface of the steel disk, the coefficient of friction when using a fus is 1,7–3,3 times lower than when using Vaseline, PMS-100 and soap stock as lubricant.

Based on the provisions of the discharge percolation theory, an interpretation is given for the mechanism of the effect of carbon nanoparticles introduced into the electrolyte on the microarc oxidation process. The effect of graphene-like carbon particles (GC) on the main characteristics of the formed coating is studied using the D16 alloy as an example. It is established that GC introduced in silicate-alkaline electrolytes at a concentration of 250–1000 mg/l intensifies microplasma processes, which is directly evidenced by an increase in the coating thickness by 1.3–2.2 times. At the same time, the participation of graphene particles in the process of coating formation leads to an increase in the content of corundum in it and, as a result, to an increase in microhardness up to 25 GPa relative to 15 GPa for unmodified coatings.

The paper discusses the realization of high dimensional stability of products, including minimization of thermal strains by the use of additives having negative coefficient of linear thermal expansion, as well as auxetics having negative Poisson’s ratio. Mechanisms of change of thermal stress state of the porous, dispersion-reinforced and layered materials are established during heating and cooling, depending on elasticity moduli, the size of inclusions, a parity of rigidity of the matrix and the filler as well as boundary conditions. The results of structural design make it possible to improve dimensional stability and reduce residual stresses of microelectronics elements, precise equipment for aerospace engineering and measuring instruments.

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U 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.)

The design and scheme for manufacturing fuel rods metallurgically bonded with ribbed aluminum claddings using hot isostatic pressing and contact-reactive brazing are presented. It is shown that the developed scheme can be used both for production of dispersive fuels and high-density fuels based on uranium alloys. The results of investigations of brazed joints of aluminum cladding with a matrix composition based on aluminum and with samples of E110 alloy through copper and silumin coatings are presented. The results of research of brazed joints of an aluminum cladding with an aluminum-based matrix composition and samples of zirconium alloy E110 made through copper and silumin coating are presented. The strength of brazed joints, composition of diffusion layers formed as a result of contact-reactive brazing in a high vacuum have been determined. The modes of hot isostatic pressing that provide crimping of the ribbed cladding of fuel pellets and rods and obtaining a metallurgical bonding between their surfaces have been defined. It is shown that satisfactory bond strength is provided starting from the temperature of 610 °С. The maximum strength values obtained on the compounds Al-(Al+12% Si)-Zr and Al-Cu-Zr are 57.0 MPa and 55.3 MPa respectively. The fracture of the of aluminum samples joints, obtained with the Cu layer at a temperature of 620 °C, occurs on threaded joints at the strength value of 82 MPa. The results of research of the composition of diffusion layers formed by brazing compounds Al-(Al + 12% Si)-Zr and Al-Cu-Zr are presented. It was established that hot pressing provides the best results for manufacturing of fuel rod dummies in the studied range of modes at a temperature of 630 °C, a pressure of 380 MPa and exposure of 20 minutes.

Introduction. Microhardness and wear resistance of the aluminum alloy (AK5M7) after its surface treatment through electrospark doping (ESD) using A (Cu) and P (Cu+P) electrodes with different applied energy is considered. The work objective is to study the relationship of the physicomechanical and strength properties of the surface of AK5M7 alloy obtained after ESD with copper and copper-phosphorus electrodes.Materials and Methods. X-ray diffraction and X-ray fluorescence analysis methods were used to determine the phase composition, coherent-scattering regions (CSR), and the surface microstrain.Research Results. It is established that with increasing energy, the values of microhardness and wear resistance increase when using both electrodes. The sample was modified by P electrode with the energy of 0.79 J. In this case, the maximum value of microhardness increased 5.3 times, wear resistance -1.6 times. It is found that with ESD, new intermetallic phases of Al2Cu and Cu3P are formed on the surface of the alloy under study. If the value of the energy used is maximum (0.79 J), the concentration of the Al2Cu phase increases 5 and 9 times with A and P electrodes, respectively, and the concentration of the Cu3P phase increases more than 4 times when using P electrode. The experimental data obtained suggest size reduction of the CSR and an increase in the microstrain values for all the Al, Al2Cu, and Cu3P phases on the surface.Discussion and Conclusions. An increase in energy with the ESD involves an increase in the defective factors and a change in the phase composition of the newly obtained surfaces. This may explain the increase in wear resistance of the surface.

In this article, there is some special features of obtaining dissimilar butt-welded and lap-welded joints for various material systems. The scheme for obtaining butt-welded joints of aluminum to steel with tool displacement is analyzed. The analysis of quality and structure of welds that were manufacturing using this scheme is being conducted. The transverse micro-section of obtained specimen of the weld of aluminum alloy AMG6 to stainless steel 12H18N10T of 2 mm thickness at a welding speed of 50 rpm and a transverse speed of 50 mm/min with a tool displacement of 0,2 mm to steel part are investigated. Mutual invasion of metals to a depth of 3,2 mm and steel inclusions in an aluminum alloy of up to 0,3 mm in size are observed in the weld seam.

Copyright of Technical Diagnostics & Nondestructive Testing / Tekhnicheskaya Diagnostika I Nerazrushayushchiy Kontrol is the property of International Association Welding (Paton Publishing House) 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 News of Kazakhstan Science / Novosti nauki Kazahstana is the property of NCSTE (JSC National Center for State Scientific and Technical Evaluations) 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.)

Background. Creating coatings for metal surfaces with high plasticity, corrosion resistance and wear resistance is an urgent task. Coatings made of Al Co powder (Al-82%, Co-18%) were applied. Aluminum alloys combine low density, high specific strength, electrical and thermal conductivity, ductility and viscosity, corrosion resistance, and form intermetallic phases. Purpose: the formation of a coating having in its composition of the strengthening phase on the basis of nitrides and oxides. Improving the characteristics of alloys is achieved by alloying them with additives (Sc, Nb, Hf and Ti) and remelting these alloys with an electron beam. Methodology. The high temperature (up to 2000 K) and the gas flow rate (up to 6000 m/s) were provided by the magnetohazodynamic flow in the interelectrode gap under the influence of ponderomotor forces. Energy for the formation of a gas jet and plasma chemical synthesis was supplied from a capacitor converter with output parameters: with a capacity of 600 μF and a voltage of 3.5 kV. The adhesion strength of the coating to the substrate was measured by scraping a diamond pyramid on the cross-section surface of the proposed coating. The adhesion values range from 12.5 to 22 kg / mm² (125 to 220 MPa). Originality. It is shown that the implanted W in the Al-Ni coating moves deep into the coating as a result of electron beam irradiation with an effective diffusion coefficient Dw=2x10-7 cm²/s. As a result of electron beam melting, the formation of AlO and NiO oxides and the more complex AlO2Ni oxide is possible. Findings. Measurements have shown that the hardness of the proposed coating is almost twice as high as the hardness of the substrate itself - copper. An increase in the hardness of the transition layer of the coating - copper by 20-30% was found. [ABSTRACT FROM AUTHOR]

Copyright of Metallophysics & Advanced Technologies / Metallofizika i Novejsie Tehnologii is the property of G.V. Kurdyumov Institute for Metal Physics, N.A.S.U 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.)

The possibility of changing bronze in the manufacture of monometallic cast plain bearings with multicomponent aluminum antifriction alloys is considered. Due to alloying of aluminum with tin, lead, copper, zinc, silicon, magnesium and titanium, it was possible to create alloys with increased ability to adapt friction surfaces. According to laboratory tests, the main results of which are given in the article, it is proved that aluminum alloys on a complex of mechanical and tribotechnical properties are close or superior to the investigated bronze BrO4C4S17. Laboratory tests have shown the possibility of manufacturing monometallic plain bearings from experimental cast aluminum alloys, which by mechanical properties are not inferior to the most solid among antifriction bronzes - bronze BrO4C4S17. On a complex of tribotechnical properties, experimental alloys exceed bronze. Due to their high-fusibility, lower density, lower cost and better workability, aluminum alloys have an almost 3-5-fold advantage over economic indicators before tin bronzes. The scope of the proposed alloys will be determined in the course of bench and operational tests. To date, an experimental batch of monometallic bearings of turbochargers TK 33N-02 has been manufactured from the alloy of the AO6S3M4CT series of “Spets Dizel Servis” (Novosibirsk), which successfully passed the bench tests. Bushings 3404.00.112, 3404.00.032 and bearings 3409.00.20, made from an experimental alloy, showed the possibility of replacing the standard bronze BrO8S12 in these turbochargers. It is advisable to carry out operational tests of bearing sleeves from the alloy AO6S3M4CT for turbochargers TK 34, TK 30 and TK 33, as well as bearing inserts for diesel locomotives.

Copyright of Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics 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.)

The influence of the parameters determining different duration of electrodynamic effect on reduction of the level of residual stresses in the welds of butt joints of the aluminum AMg6 alloy as a result of electrodynamic treatment was investigated. It is shown that an increase in the duration of electrodynamic effect, achieved by growing in the inductance of the discharge circuit at constant amplitude values of a pulsed electric current, is characterized by a greater increase in the period of current decay as compared to the period of its increment. At the same time, the increase in the duration of electrodynamic effect leads to an increase in the efficiency of the method for reducing the level of residual stresses in the welded joints of the AMg6 alloy. It is noted that at a duration t ≥ 0.7 ms, the decrease in stresses is determined by the intensity of electrodynamic effect and the Joule heating of the plate surface. 5 Ref., 1 Tabl., 4 Fig. [ABSTRACT FROM AUTHOR]

The work presents the results of numerical modelling of thermal fields in zone of joining of aluminum plates through intermediate layers in process of local heating of joining zone by fl at heater, contacting with one of the plates. The layers consisting of solder alloy, multilayer reactive foil or layers of both types were considered as an intermediate layer. The calculation was carried out considering thermal-physical characteristics of the plate material, intermediate layer and heater, consisting of the multilayer reaction foils, in which a reaction of self-propagating high-temperature synthesis is accompanied by intensive heat emission. There were studied the conditions of local heating of the aluminum plates necessary for obtaining the permanent joints in the process of their soldering or welding through intermediate layer. 14 Ref., 1 Tabl., 11 Fig. [ABSTRACT FROM AUTHOR]

The car industry uses a tremendous number of materials to build cars, including iron, aluminum, steel, glass, rubber, petroleum products, copper, steel and others. These materials have evolved greatly over the decades, becoming more sophisticated, better built, and safer. They've changed as new automotive manufacturing technologies have emerged over the years, and they're used in increasingly innovative ways. This article is devoted to systematization information on the introduction and application of modern materials in the automotive industry. Given both domestic and foreign sources of information, it follows that car manufacturers are constantly pushing to create the lightest cars possible to increase speed and power. Research and development into lightweight materials is essential for lowering their cost, increasing their ability to be recycled, enabling their integration into vehicles, and maximizing their fuel economy benefits. Light weighting without loss of strength and speed properties is the present, and the future, of the automotive manufacturing industry. It brings innovative materials to the frontline of design.

The paper presents the results of a study on the effect of a method for dispersing the size of the component of the dispersed phase separation coatings used in high pressure die casting aluminum alloys.

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 Electronic Processing of Materials / Elektronnaya Obrabotka Materialov is the property of Institute of Applied Physics 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.)

The paper presents the results of research on the study of the possibility of accumulation of the lubricating layer coating on the surface of the separation process of foundry equipment with high pressure die casting aluminum alloys.

The influence of equal channel angular pressure on the microstructure and mechanic properties of aluminum alloy Al-14%Cu-7%Ce, the influence of dragging on the microstructure and failure surface of wire samples of aluminum alloy Al-14%Cu-7%Ce was study.

Using system approaches provides essential development of traditional methods in materiology and their effective application for objects with difficult multiscale structure and for nano-structural materials as well. It shows application of complex physical and chemical analysis, multifractal and wavelet analysis to describe material structures in qualitative and quantitative way, which allows revealing the differences poorly distinguished with other separate methods and estimating system characteristics of material structures and characterizing the process in self-organizing in structures. Formation by tearing of friction surface structures for composite materials with additives of Al2O3 and SiC is described in comparable thermodynamic conditions. Adding SiC in comparison with Al2O3 promotes to a lesser extent fragmentation and increase in frequency of setting and breaking processes. Adding graphite to reinforced SiC composite material results in increase in nonequilibrium of thermodynamic condition of structure formation. Additional introduction of graphite in even greater degree strengthens distinctions between materials with SiC and Al2O3 additives, which results in formation of the least ordered structures of friction surface.

Copyright of Journal of Mechanical Engineering the National Technical University of Ukraine 'Kyiv Polytechnic Institute' is the property of National Technical University of Ukraine KPI 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.)