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TECHNOLOGY OF PLASMA METALLIZATION OF THE WOOD AND FIBROUS BOARD

https://doi.org/10.34031/2618-7183-2018-1-3-4-10
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 4-10 p.
Abstract
The scientific and technological principles of metallization of products on the basis of wood with use of plasma high-temperature dispersion are developed. For the purpose of prevention of impact of the highest temperatures of a plasma stream on a front surface wood and fibrous board (fibreboard) an intermediate layer was put.
The structure of an intermediate protective layer, the including mix of epoxy resin with refractory filler is developed. Operation of drawing a protective intermediate layer included several specially developed technological stages. For the subsequent metallization such non-ferrous metals as copper and aluminum in the form of a wire are used. Optimum parameters of plasma dusting of metals on a front surface of a fibreboard are determined
The protective and decorative covering on the basis of non-ferrous metals had high aesthetic consumption and performance properties. The covering possessed the increased coefficient of diffusive reflection and high durability of coupling with a matrix. The dependence of influence of thickness of the raised dust metal covering on durability of coupling of a covering with a substrate is established.
The developed technology of metallization of products from wood in comparison with traditional technologies, allows to lower significantly time of metallization and energy consumption and to increase competitiveness of products both on internal, and on external the markets.
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STUDY OF ARTIFICIAL CERAMIC BINDERS BASED ON SILICATE MATERIALS FOR CERAMICS INDUSTRY

https://doi.org/10.34031/2618-7183-2018-1-3-11-16
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 11-16 p.
Abstract
This article discusses the possibility of using artificial ceramic binders obtained by the technology of highly concentrated binder suspensions in the production of ceramic materials and products. The results of complex studies of suspensions of artificial ceramic binders based on feldspar and quartz sand, as well as the results of tests of the samples obtained on their basis are presented. A definite advantage of entering the suspensions in the molding compositions of the slurries used in the manufacture of certain varieties of pottery is proved. The solution of the problem of import substitution of raw materials components, caused mainly by the difficult political situation in the country, as well as the lack of its own raw material base of good quality, in connection with which the paper proposes the use of technology of highly concentrated binder suspensions, which allows to optimize the quality of domestic raw materials. The use of technology of highly concentrated binder suspensions, allows not only to expand the assortment and range of products produced by this technology, but also to improve the quality and economic feasibility of individual varieties of ceramics. The emphasis on the introduction of technology of highly concentrated binding suspensions in certain areas of ceramics production is explained by the formation of a completely different structure of materials due to the increased content of nanoparticles in the composition of artificial ceramic binding suspensions, which contributes to a significant increase in mechanical strength while optimizing other basic technological quality indicators for ceramic materials and products. The possibility of reducing the firing temperature by 50-100°C, however, this issue requires additional research.
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INFLUENCE OF ZnO AND BaSO4 ADDITIVES ON CONSTRUCTION AND TECHNICAL PROPERTIES OF THE WEAK BASE WHITE CEMENTS

https://doi.org/10.34031/2618-7183-2018-1-3-17-24
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 17-24 p.
Abstract
White cement – modern construction material which is increasingly popular every year as it is used not only in the construction sphere, but also and in creation of architectural products.
Today the most famous producers of white cement is Turkey, Denmark and Egypt. Special color of cement is reached due to specific structure and the specialized production technology. Clinker for the white portlandtsement, differs from usual in the increased maintenance of Si2O (23.5-25.5%) and A12O3 (5.5-7%), insignificant quantity of Fe2O3 (up to 0.25-0.35%) and MnO – 0.05-0.15%. The mineral composition of clinker for white cements fluctuates within (%): C3S – 35-50; 35-45; C3A 14-17; C4AF 0.9-1.4. The maintenance of MgO in it should not exceed 4.5%. For production of the white portlandtsement the cleanest kinds of carbonate and sandy-argillaceous raw materials are used. In particular, the straight limestones or chalk containing no more than 0.15% of the painting oxides are applied. The kaolin, waste of its enrichment and other materials are served as a clay component. The fine-grained white quartz sands, waste of quartz sand received at enrichment of a kaolin, etc. to increase in the silicate module are applied.
The ashless fuel which is not forming soot and ashes that helps to avoid pollution is applied to roasting of clinker. Crushing of raw materials is carried out in special mills, and crushing is carried out by means of silicon or porcelain elements. Such production technology helps to achieve the grinding having higher rates than from traditional cements.
Results of a research of influence of mineral BaSO4 and ZnO additives on synthesis and properties of the low-main clinker of the white portlandtsement are given in work: clinker formation, hydration activity, whiteness of cement.
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THE USE OF SEMI-AQUATIC CALCIUM SULFATE TO INTENSIFY THE PROCESSES OF HARDENING OF STRUCTURAL HEAT-INSULATING FOAMED CONCRETE

https://doi.org/10.34031/2618-7183-2018-1-3-25-32
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 25-32 p.
Abstract
Construction of energy- and resource-saving housing of increased comfort involves the creation of more efficient building materials in comparison with traditional and new designs of fencing buildings with im-proved thermal properties. The problem of energy saving in construction has determined the direction of creation and production of effective cheap materials with high thermal properties. One of the most promising materials of this type is environmentally friendly, non-combustible cellular foam concrete.
The problem of accelerating the setting and hardening of foam concrete mixtures, as it allows to accelerate the turnover of forms and reduce the time from manufacturing to sending the finished product to the consumer is of great practical interest.
However, in most cases, domestic foaming agents are produced and used without additional input of setting and hardening regulators. This is due to the fact that the compatibility of the latter with the main additive – foaming agents is not sufficiently investigated. This problem is quite complex, as some setting accelerators can cause defoaming, worsen the structure of the foam matrix, reduce the mechanical strength of the stone and have other negative effects. At the same time, properly selected setting accelerators enhance the action of foaming agents
In the work the questions of application of semi-aqueous calcium sulphate (SCS) for intensification of hardening of foam concrete are considered. The change in physical and mechanical characteristics of foam concrete prepared on anionic and cationic blowing agents with an additional content of 1, 2 and 3% semi-aqueous calcium sulphate is shown. It is established that the SCC allows accelerating the hardening processes, and the formation of ettringite does not cause strong internal stresses, which is related to the porous structure of the material.
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ADDITIVE TECHNOLOGY IN CONSTRUCTION

https://doi.org/10.34031/2618-7183-2018-1-3-33-42
 33-42 p.
Abstract
The main innovative technologies of construction 3-D printing in modern construction are considered. This direction of research confirms the relevance of the selected issue. Development of compositions for building 3D printing allows for construction of not only individual constructions, but also buildings and constructions in general. Experimental compositions with effective for building print supplements will receive enough dense structure of concrete are developed. To assess the use of quartz sand for use in 3-d printers studies were conducted of their basic properties. The role of additive technologies in modern construction in the construction of buildings and structures that will lead to future changes in the construction market.
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STUDY OF PHYSICAL AND MECHANICAL CHARACTERISTICS OF VARIOUS TYPES OF SOIL STRENGTHENED BY CLINKER WASTE

https://doi.org/10.34031/2618-7183-2018-1-3-43-50
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 43-50 p.
Abstract
The specificity of the construction of roads is the use of a huge amount of various stone materials - sand, gravel, etc. To reduce the cost of road pavements, it is possible to replace stone materials with local soils. Such materials do not need to be transported by road or rail. It is known that most soils cannot be used in the construction of the road bed (sandy loam and loam are light dusty and heavy dusty, clay dusty and oily), as their use leads to the appearance of various deformations of the upper layers of road pavement. This problem can be solved by strengthening the soil with various types of binders, in particular, clinker waste. When conducting experimental studies to assess the effectiveness of the use of waste clinker production to strengthen the soil the following compositions without using: soil and 9% waste; soil and 18% waste; soil and 27% waste were investigated. As a result of the research, the main dependences of the changes in the physical and mechanical parameters of the soil concrete on the amount of waste clinker production introduced into the composition of various types of soils were identified. It was found that the use of waste clinker production to strengthen the loam allowed to obtain a reinforced soil brand M20. Strengthening sand with clinker production without the addition of cement is not practical, as the samples do not gain even minimal strength for 180 days, which allows them to be classified by brand, in addition, such samples have extremely low resistance.
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INVESTIGATION OF INFLUENCE OF PLASMOCHEMICAL MODIFICATION ON MACRO- AND MICROSTRUCTURE OF SURFACE LAYER OF AUTOCLAVE WALL MATERIALS

https://doi.org/10.34031/2618-7183-2018-1-2-4-10
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 4-10 p.
Abstract
Studies of the high-temperature effect of a plasma torch on the formation of a multilayer structure of the protective and decorative coating of autoclave wall materials are presented. The tasks of the work included studies: a temperature gradient in a multilayer protective-decorative coating; chemical composition of the fused, intermediate and deep layers of the protective and decorative coating; influence of sodium liquid glass on the formation of macro- and microstructures of protective and decorative coatings under the influence of plasma; processes of thermal diffusion and redistribution of oxides in the fused, intermediate and deep layers.
It was found that when the plasma torch was treated with autoclave wall materials, the surface layer was heated to a depth of 3000 μm, and the maximum surface temperature reached 2000 °C. The pattern of the change in the structure of the fused and intermediate layer is revealed. It is shown that the preliminary impregnation of the surface of silica brick during plasma treatment due to the formation of a low-melting melt eliminates microcracks in its deep layers, and high plasma temperatures promote intensive evaporation of sodium and calcium oxides from the fused layer.
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PLASMOCHEMICAL MODIFICATION OF WALL BUILDING MATERIALS

https://doi.org/10.34031/2618-7183-2018-1-2-11-18
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 11-18 p.
Abstract
The aim of the work is to study the effect of a high-temperature plasma torch on the processes of phase transformations and layer-by-layer modification of the protective and decorative coating on concrete using as a filler a mixture of quartz sand and hollow glass microspheres. The main tasks included: investigation of the processes of evaporation and thermal diffusion of oxides of plasma-coated coatings; study of phase transformations in the melt and its subsequent crystallization in the process of rapid spontaneous cooling of the fused protective and decorative coating; study of the effect of sodium liquid glass on the processes of polymorphic transformations of alumina and the formation of micro-wicks due to the intense diffusion of sodium oxide; study of operational characteristics of protective and decorative coatings. It was established that the initial phases in the protective-decorative coating are α-Al2O3 and CaO∙6Al2O3 (β-Al2O3), and the liquid sodium glass in the coating leads additionally to the formation of Na2O∙11Al2O3. The top layer of the protective and decorative coating is Na–Ca–Al–Si glass with regions of heterogeneities containing an increased content of sodium oxide. The content of aluminum oxide in the protective and decorative coating based on the battle of high-alumina refractory was 95.1 %. The introduction into the coating composition of sodium liquid glass minimizes the processes of dehydration of the binding component and changes the chemical composition of the protective and decorative coating. Reduction of the aluminum oxide content to 83.0 % affects the microhardness indicators. Microhardness of the concrete surface due to the introduction of liquid glass is reduced from 2510 HV to 887 HV.
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INCREASING THE STRENGTH AND FROST RESISTANCE OF CERAMIC PRODUCTS AT USING MELASSES BARDS AS PLASTICIZER

https://doi.org/10.34031/2618-7183-2018-1-2-19-29
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 19-29 p.
Abstract
Ways of production of ceramic materials with use as the plasticizing additive of the sulphitic and alcohol bards (SAB), the calcium citrate filtrate (CCF) which is liquid withdrawal of production of citric acid in the microbiological way are known. However introduction to raw mix of CoB reduces forming humidity and fall of the formed products insufficiently, and an essential lack of FTsK is the low durability of products on compression with a big volume mass of samples.
In work the possibility of use as the plasticizing additive to a clay lot of withdrawal of the spirit industry – melasses bards is investigated. As a part of molasses the remains of amino acids and other organic substances which have the plasticizing effect on clay materials contain. On the example of natural clays of three various fields the plasticizing action melasses bards is proved, and the number of plasticity of the studied clays increases in direct ratio to increase in additive melassny bards in clay raw mix. It is shown that introduction to raw mix melasses bards leads to improvement of appearance of pottery, decrease in jointing, increase in durability for Veselovsky clay for 7%, for the Oryol clay for 67%, for Bessonovskaya – for 23%.
Research of the received ceramic samples on frost resistance according to requirements of GOST bards unlike the products which aren’t containing additive bards showed high frost resistance of products with additive melass. Also lowered decrease in durability and loss of mass of the samples containing additive melassny bards is noted.
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OPTIMIZATION OF RECEPTURAL-TECHNOLOGICAL PARAMETERS OF MANUFACTURE OF CELLULAR CONCRETE MIXTURE

https://doi.org/10.34031/2618-7183-2018-1-2-30-36
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 30-36 p.
Abstract
Aerated concrete at the moment is one of the perspective thermal insulation materials. However, the production of high-quality aerated concrete products is associated with a number of difficulties, primarily related to the features of the manufacturing technology and, in particular, to the formation of its structure during the period of gas evolution and the impact on this process of a large number of factors. The best conditions for the formation of cellular concrete are created when the maximum gas release and the optimum values of the plasticity-viscous characteristics of the aerated concrete mixture are found. Achieving optimal conditions is extremely difficult, which leads to a deterioration in the physico-mechanical characteristics of the final products. One of the ways to solve this problem is to increase the amount of mixing water, however, along with a positive effect (reducing the viscosity of the system), this leads to a decrease in the gas-holding capacity of the mixture. In this connection, the possibility of increasing the production efficiency of the cellular concrete mixture by optimizing the recipe-technological parameters was considered. With the help of the method of mathematical planning, a three-factor experiment was carried out, as the factors of variation were: the duration of the preliminary aging of the mixture, the dosage of the blowing agent and the water-hard ratio, the output parameters were the compressive strength and the average density of the final products. The obtained results made it possible to reveal the regularities of the change in the output parameters from the variable factors and to establish that the preliminary aging of the mixture before the introduction of the gassing agent positively affects the structure and, as a consequence, the physico-mechanical characteristics of the final products.
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