Кераміка: наука і життя

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ISSN / EISSN : 25216694 / 25216708
Total articles ≅ 92
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G.K. Voronov, A.I. Fesenko, O.V. Savvova, S.O. Melnyk, O.P. Dehurko
Кераміка: наука і життя pp 7-13; doi:10.26909/csl.4.2019.1

Abstract:The article presents the results of a study of stone processing waste in order to justify the implementation of the technological process of manufacturing architectural and construction products with their use. The structure of the distribution of waste arising from stone processing processes is given. The analysis of the relevance of the problems of utilization of slurry waste stone processing. Studies were conducted to determine the chemical, mineralogical and phase composition of stone waste. It was found that these wastes belong to gabbro-diabase rocks, which was confirmed by their chemical and mineralogical composition. The main mineral components are plagioclase, pyroxene and minerals of the iron group. The moisture content of the initial pulp and the particle size distribution of dry sludge were determined. Based on the results of establishing the melting temperature and fire resistance of baked sludge samples, the possibility of obtaining architectural and construction products based on dry sludge using ceramic technology (semi-dry pressing and sintering) was established, for which a selection of technological parameters and initial mass compositions was carried out. The promising compositions of ceramic masses with a significant sludge content (up to 60%), as well as the temperature-time regimes of the formation of ceramic materials, which are in the range from 1100 to 1200°C, are determined. The physicomechanical properties for sintered ceramic materials are studied, namely, mechanical strength compression (up to 55 MPa) and wear resistance (up to 0,45%), which corresponds to the properties of clinker ceramic materials. Based on the foregoing, a conclusion was drawn on the prospects of using stone slurry for obtaining ceramic products for architectural and construction purposes.
V.V. Glukhovskyi
Кераміка: наука і життя pp 26-30; doi:10.26909/csl.4.2019.4

Abstract:The results of scientific research in realization of energy-intensity cellular concrete production technology of normal condition hardening are shown. Physical-mechanical and thermophysical properties of cellular concretes, which are produced by this technology, are relevant to active normative documents. In this case the produced cellular concretes are characterized with strength increasing in time in compare to autoclave hardening cellular concretes and aerated concrete. The influence of the chemical activity of the fillers on the performance of the final product has been established. According to the results of the performed researches it is established that the activity of the filler determines the kinetics of change in the time of the strength of the composition, which solidifies under normal conditions. When used as ground coal ash filler, the level of strength of porous concrete at the age of 28 days is at the level of strength of the composition with the addition of ground granulated slag (3,22 and 3,38 MPa, respectively). It is also found that, unlike autoclaved aerated concretes, the strength of aerated concretes of normal cement based on Portland cement increases over time both on binder without mineral additives and in the presence of ash, milled slag and quartz sand. The intensity of the process of gaining strength over time is determined by the activity of the mineral additive. When used as a mineral admixture of non-ground quartz sand, which, under normal curing conditions, does not interact with the curing of Portland cement, the strength of the porous concrete decreases with increasing amount of this additive in the composition. The intensity of the strength of these compositions at the age of 90 days, depending on the amount of additive, is 10 - 18%. The proposed technology for the production of cellular concrete based on Portland cement, curing under normal conditions, was implemented in industrial production. D700 concrete was selected as the base for production.
Zh.O. Petrova, V.M. Vyshnievskyi, Yu.P. Novikova, A.I. Petrov
Кераміка: наука і життя pp 21-25; doi:10.26909/csl.4.2019.3

Abstract:The technology of drying colloidal capillary-porous materials to a final humidity of 6-8%, developed at the Institute of Technical Thermophysics of the NAS of Ukraine, allowed to obtain a brittle state, in which it is possible to grind this product to small particles. The most suitable for industrial grinding of the dried composite colloidal capillary-porous materials is the impact method, because when wiping and crushing the material has accumulated, stuck to the working surface. Powders are characterized by one pronounced maximum corresponding to the particle size of the powder of 0,16 mm. As the rotation speed of the shredder rotor changes, the particle size distribution of 0,16 mm increases by reducing the larger particles. The amount of powder thus obtained is directly proportional to the speed of rotation of the rotor. The study of the dispersion and classification of functional powders showed that all powders have the largest particle size of 0,16 mm. The maximum yield of this fraction is 70% and the lowest is 40%. The structural-mechanical characteristics of powders from composite colloidal capillary-porous materials were investigated for the first time. Characteristics of different fractions were determined by such parameters as bulk density, vibration density, angle of natural slope, speed of material flow through the funnel and others. Studies to determine the structural and mechanical properties of functional powders have shown that they can be attributed to more bulk powders, as opposed to highly bound monopowders. Creating compositions improves their structural and mechanical properties.
V.V. Korskanov, O.M. Fesenko, T.V. Tsebrienko, O.P. Budnik, V.B. Dolgoshey
Кераміка: наука і життя pp 14-20; doi:10.26909/csl.4.2019.2

Abstract:The objects of study were water dispersions of raw graphene (hereinafter referred to as graphene-n), higher degree of purification of graphene samples (hereinafter graphene), and nanoparticles of graphene-Au nanoparticles based on them. The thermal conductivity of water graphene dispersions and water dispersions of gold graphene nanoparticles nanostructures at different temperatures and component ratios was investigated. The values ​​of effective thermal conductivity of dry nanofillers are calculated. The temperature dependences of the thermal conductivity of the nanofillers were obtained. It is found that the in-thermal conductivity of water dispersions of purified graphene is higher than the thermal conductivity of raw graphene as a result of better packing of nanoparticles in pure graphene nanofillers compared to raw. The effect of enhancement of thermal conductivity of gold nanoparticles, which is accompanied by higher absolute values of thermal conductivity of nanoparticles of graphene-nanoparticles of gold than the corresponding graphene, was revealed. At the same time, there is a significant difference in thermal conductivity between nanoparticles of graphene nanoparticles of gold. It is established that higher values of thermal conductivity of graphene-nanoparticles nanostructures of gold are the result of the reinforcing action of a gold nanoparticle substrate, which is formed as a result of joint sedimentation with graphene during the formation of nano-flakes from water solution during evaporation of water.
V.V. Korskanov, O.M. Fesenko, P.P. Pogoretskiy, O.P. Budnik, V.B. Dolgoshey
Кераміка: наука і життя pp 31-41; doi:10.26909/csl.4.2019.5

Abstract:Today, Ukraine has retained a fairly strong scientific potential. However, the level of patent and innovation activity in Ukraine is low, because the state provides for a small percentage of the gross domestic product (GDP) that goes to finance research. In recent years, the number of research works and staff of research institutes has been shrinking rapidly due to chronic underfunding and outdated experimental research equipment. For the same reason, the citation index of works of Ukrainian scientists is low. The weak material base of the Ukrainian research institutes stipulates that the ratio of experimental to theoretical scientific and technical developments has been decreasing in recent years. Most patents are registered by Ukrainian scientists in Ukraine - in Ukrpatent. The majority of international patents are granted to Ukrainians in the USA, Germany and Switzerland. Against the background of the integration of Ukrainian scientists into the world community, there is a significant increase in the number of joint scientific publications of Ukrainian scientists with foreign colleagues. In recent years, the world has seen a rapid increase in patents on nanotechnology in the most technologically advanced countries in the world. The patent and innovation activity in Ukraine is expected to grow rapidly in the near future. The main goal is to ensure rapid and qualitative transformation of creative ideas into innovative products and services that increase the level of innovation of the national economy.
L.P. Chernyak, P.G. Varshavets, N.O. Dorogan, O.M. Shnyruk
Кераміка: наука і життя pp 16-22; doi:10.26909/csl.3.2019.2

Abstract:The possibility of making of mineral astringent material of the low temperature burning at utilization of wastes of production of paper – scope is shown. The analysis of compositions of raw material mixtures on the basis of the system chalk -clay-scope is conducted with varying of concentration of scope at the set descriptions of product of burning. The compositions of mixtures with introduction of 25 - 51 % scope is determinated. The features of phase composition and indexes of properties for mineral astringent with the use of scope as technogenic raw material are shown at the maximal temperature 1100 0С of burning. Industrial use of multi-tonnage waste of various industries, including scopes from paper production, allows to solve complex issues of technology of production of silicate materials, resource conservation and ecology. The feasibility of using scopes as man-made raw materials in the technology of mineral binders is determined by the peculiarities of the chemical and mineralogical composition - the presence of a complete complex of oxides necessary for the formation of a given phase composition during firing and the possibility of intensification of the sintering increase in the reactivity of the silicate system at. The efficiency of practical use of an osprey on the basis of the above developments is defined as the prospect of increasing the volume of utilization of industrial waste, as well as obtaining a new kind of mineral binder material in the low-temperature firing, which differs from romance with improved strength indicators.
K.V. Kirilenko
Кераміка: наука і життя pp 23-29; doi:10.26909/csl.3.2019.3

Abstract:In the context of rising energy costs and the need to use new energy sources, works aimed at raising the surface temperature of heat radiators with reduced energy consumption are of particular importance, and it is especially important if these processes are also accompanied by the effects of self-stabilization. Bulk materials do not possess these properties. However, materials whose dielectric matrix is also an active element can provide up to 10 - 30% of the thermal energy that will be released in the material, thereby increasing the surface temperature and without increasing energy consumption. Therefore, the study of composite materials with different matrices is relevant. This article the influence of the matrix material on the electrical properties of composite materials was examined. It was established that the microstructure morphology of resistive materials changes significantly depending on the matrix type. In composites based on matrix AlN, for the entire range of concentrations HfC, conducting cluster is formed with a metallic conductivity. For composite systems Al2O3-HfC and Si3N4-HfC thermoactivated hopping conduction between nearest neighboring states observed. Thus, for materials based on Si3N4 matrix at temperatures up to 300°C observed reduction of charge carriers concentration with increasing temperature. The approximation of the temperature dependence of the electrical conductivity was carried out on the basis of the following possible variants of the nature of the electrical conductivity, namely: jump conductivity (nonlocalized states, localized states in the tails of conduction and valence bands, localized states near the Fermi level), tunneling. It can be assumed that the formation of conductive clusters occurred under the influence of two factors: magnetic field and mechanical loading. When using the AlN matrix, the influence of the magnetic field on the structure formation is smallest. This conclusion can be drawn from the fact that the formed conductive clusters have the appearance of a linear chain structure.
S.V. Gulienko
Кераміка: наука і життя pp 30-33; doi:10.26909/csl.3.2019.4

Abstract:The urgent task is to research in detail the possibilities of operation of the reverse osmosis membrane in the conditions of changing various parameters, which include, first of all, the working pressure, the initial concentration of the cleaning solutions, as well as the working conditions and the complete set of cleaning stands with auxiliary filters: mechanical, ceramic and carbon, which improves the quality of water and increases the life of high-value reverse osmosis modules. Particular attention was paid in this series of experiments to the role of ceramic filters, since in the previous series of experiments the concentration of the solution did not change both after mechanical and after carbon filters. Therefore, it was decided to modernize the stand and use a ceramic filter in the flow chart. In this work the detailed scheme of bench-scale setup with using of ceramic and carbon filters and also reverse-osmosis module is represented. The experimental reseaches of purification of NaCl water solutions were carried out in wide range of concentrations (0,2∙10-3…6,5 g/l) and working pressures (0,2…0,65 MPa). The comparative characteristics of main process parameters with and without ceramic filter are represented. The experiments were carried out on a laboratory stand for complex purification of aqueous solutions by microfiltration, adsorption and reverse osmosis using the following process steps carried out in the respective apparatus.
O.V. Savvova, S.A. Ryabinin, E.A. Svitlichniy, G.K. Voronov, A.I. Fesenko
Кераміка: наука і життя pp 8-15; doi:10.26909/csl.3.2019.1

Abstract:Advanced methods for obtaining high-strength glass-ceramic materials based on lithium aluminum silicate glass for glass and ceramic technologies are identified. Were analyzed forming methods: pressing, thermoplastic molding and slip casting with the definition the advantages and disadvantages of in each of them. The choice of the base LAS system is substantiated and model lithium-aluminum-silicate glasses and glass-ceramic materials based on β-spodumene are synthesized by the methods of pressing, slip casting and thermoplastic molding. The features of the formation of glass-ceramic materials using various technologies are investigated. Technological parameters were established for pressing: molding powder with a fraction size from 63 to 125 μm − 70 vol. %, from 25 to 63 microns − 15 vol. %, less 25 microns − 15 vol. %, xanthan gum solution in an amount of 10 wt. %; for slip casting: slip specific weight − γ = 1852 kg/m3, pH = 9.90; for the thermoplastic formation: paraffin − 15 wt. %, beeswax − 5 wt. %, oleic acid − 1 wt. %. It has been established that the determining influence on the mechanical properties of the developed glass-ceramic materials has the character of their micro- and macrostructures. It has been established that, for the studied glass-ceramic materials, an increase in porosity and pore size significantly affects the magnitude of their compressive strength. Glass-ceramic materials obtained by wet pressing and slip technology can be recommended as the most technologically advanced in creating composite armor elements and promising in the development of high-strength glass-ceramic materials for the local protection of special equipment and technology. Composite structural materials obtained by thermoplastic processing can be used to create high-strength parts for precision mechanisms and instruments, which are subject to stringent requirements for mechanical strength.
M.T. Dovzhik
Кераміка: наука і життя pp 18-22; doi:10.26909/csl.2.2019.3

Abstract:The process of mixing the components of the mixture is an important factor affecting the physical and mechanical properties and appearance of the final product. The proposed designs of vibroexcluders for mixing fibrous concrete and the formation of flat products provided analytical formulas for calculating the process of vibration extrusion. The quantitative criterion of laminar convective mixing, which occurs when vibroexclusion, is the degree of increase in the surface area of the interface between the components, which in turn depends on the total deformation and initial orientation of the surface. The constructions of vibroextruders are provided for the mixing of a fibrous concrete and forming flat products, and analytical formulas are given for the calculation of the vibroextrusion process. The construction of a cascade vibrating extruder for the proposed mixing can be applied to a wide range of compositions of fibro concrete mixes, and a specially designed vibratory extruder for forming can significantly improve the longitudinal orientation of dispersed fittings in flat products. The degree of longitudinal orientation of the fiber in the process of vibroexclusion of fiber concrete can be regulated by the geometry and size of the channels of the vibroexcutter bunker, as well as by the application of special guiding partitions. Practically the degree of mixing is characterized by the speed of vibration exclusion. Due to the fact that the vibroextrusion mixing does not occur the destruction of fiber reinforcement, as a result of the successive passage of the mixture through several channels, the moment when the vibration excursion velocity stabilizes. The given analytical dependencies give the possibility of quantitative description of differences in the deformation of the mixture and the final orientation of fibers in the products for the proposed apparatus. The degree of longitudinal orientation fibers need to be set separately for different products, depending on their purpose, and change the degree of orientation is carried out by changing the geometry of the vane bunker vibroextruder. The results of the work are supposed to be used in the design of a new vibration excretory equipment for mixing fibrous concrete mixtures and the formation of dispersed reinforced products.