Кераміка: наука і життя

Journal Information
ISSN / EISSN : 25216694 / 25216708
Total articles ≅ 79
Filter:

Latest articles in this journal

O.O. Titova, L.P. Chernyak, L.A. Nudchenko
Кераміка: наука і життя pp 7-12; doi:10.26909/csl.1.2019.1

Abstract:Thanks to the peculiarities of the chemical composition and structure, perlite has received application for manufacturing building materials - thermal insulation and ceramic Results over of research of the silicate systems with transcarpathian perlite as raw material for making of mineral astringent material are driven. The features of the chemical-mineralogical composition, phase transformations during burning and astringent properties of material at the use of perlite from Beregovsky deposit in composition initial raw material mixtures are shown. To determine and optimize raw material stock at the production of mineral binder material of low-temperature roasting type of natural or romanticum, a computer program "RomanCem" was used. After burning with a maximum temperature of 1100°C, the test of the binder material from the investigated 3-component mixtures with Transcarpathian perlite is characterized by differences in phase composition and properties. When using for the manufacture of mineral binder material of low-temperature firing of a gypsum natural or romantic cement 3-component mixtures based on the limestone system - perlit - clay, the content of Transcarpathian perlite is possible from 4 to 22 mass. %.
A.V. Timoshchenko, Ye.V. Timoshchenko, O.V. Hyliienko, I.P. Bieliaieva
Кераміка: наука і життя pp 13-19; doi:10.26909/csl.1.2019.2

Abstract:The manuscript presents the results of the research of the kinetics of radiation drying of basalt-bentonite cardboard. It has been established that in the case of high-temperature radiation drying of cardboard, the value of the reduced first critical moisture content in the area with low values – 0.17 is observed; compared to the same indicator for convective drying of slabs 50 and 100 mm thick - 0.41 and 0.20, respectively. This feature of the process allows you to raise the temperature in the first drying chamber to 570-600°C without fear of local overheating of the material. It was noted that at the stage of the falling drying speed, which is largely implemented in the second drying chamber, in order to avoid local overheating of the material, the temperature in the chamber is limited to 440°C. The decrease in the temperature level of the process in the second drying chamber is compensated for by the active gas-dynamic environment, in which the average speed of the drying agent in the inlet action zone can reach values of ± 5 m/s. The results of the controlled operation of the pilot conveyor drying installation are given. Its satisfactory specific energy indicators are noted, which for the same type of installations can reach values of 1200-2000 kcal/kg of moisture. In conclusion, it is noted that, in addition to the traditional positions of the heat balance of the plant, an energy-efficient modernization of a conveyor drying plant should include reducing losses with a spent drying agent, with recuperative losses through walling structures, with unorganized gas exchange in the drying chamber, and such positions as efficient drying agent with the optimization of its gas dynamics in the drying chamber.
Yu.F. Snezhkin, V.м. Paziuk, Zh.O. Petrova
Кераміка: наука і життя pp 20-25; doi:10.26909/csl.1.2019.3

Abstract:The mathematical processing of experimental data obtained during the drying of spherical form of capillary-porous materials on a convective drying bench allows us to determine the influence of various factors on the process. The main factors influencing the kinetics of drying of capillary-porous materials of spherical shape are the temperature and velocity of the heat carrier, as well as the initial moisture content of the material. For each factor, the variation levels corresponding to the optimal conditions for conducting experimental studies with low-temperature drying conditions are recommended. For a mathematical description of the duration of drying of capillary-porous materials, we use an orthogonal composite plan of the second order. As a result, the proposed mathematical model of the process obtained regression equations and the response surface of the duration of drying of capillary-porous materials of spherical shape. The obtained regression equations of the drying time give a detailed description of the influence of both individual and joint actions of factors, the significance of these parameters is determined by the corresponding coefficients according to Student's criterion. Also, the adequacy of the mathematical model according to Fisher's criterion, which corresponds to the real object, is checked. The construction of the response surfaces of the drying time of capillary-porous materials indicates the nature of the effect of these factors in the given range of variation.
Ye.Ya. Telnikov, I.O. Khmara, O.M. Nedbailo, O.G. Chernyshyn
Кераміка: наука і життя pp 26-31; doi:10.26909/csl.1.2019.4

Abstract:The results of the study of the electrophysical properties of metal-ceramic compositions based on nickel boride depending on the composition, heat treatment conditions and after exposure to mixed reactor radiation (neutrons and γ-radiation) are presented. A method of metallization of piezoelectric ceramics based on materials developed using thick-film technology is proposed. The paper discusses the results of the study of physicochemical processes occurring during the heat treatment of films and their influence on the properties of piezoceramics. The advantages of thick-film technology, widely used in microelectronics, are well known, but the use of noble metals causes a number of serious production problems associated with their high cost, the need for waste management and reporting; Operational disadvantages include instability of properties (especially under mixed reactor irradiation conditions) due to the high diffusion coefficients of these metals (especially silver) and their leaching when soldering the leads. This work is devoted to the study of the electrophysical properties of pastes for thick-film metallization of piezoceramics, which do not contain extremely scarce and noble metals, burned in air, are not inferior in their operational parameters to pastes based on silver-palladium alloy and are intended to replace the latter.
O.M. Nedbailo, O.G. Chernyshyn
Кераміка: наука і життя pp 29-31; doi:10.26909/csl.4.2018.4

Abstract:In article the technique of definition factors of carrying over weight of substance in the course of roasting ceramic materials which is based on exponent dependences of change mass bodies from time of its heating is offered. The process of firing ceramic materials is associated with the transfer of heat and mass of matter. Therefore, for a more complete calculation of the heat treatment mode, it is necessary to know the conditions for the mass transfer in the product being calcined. The aim of the work is to determine the mass transfer coefficients of the substance in the process of firing ceramic materials. The mass loss rate of the bound matter or the mass loss per unit time will be directly proportional to the average mass content of the body. On the other hand, the mass loss rate of the bound matter is numerically equal to the slope of the mass content kinetics curve. Proposed in the work formulas can be applied when studying the process of mass transfer during firing of samples from different clays, as when firing clay samples of different diameters under the same conditions, they will differ in the mass content (mass loss rate of the bound substance) during heating and their final relative amount (mass content) of the lost mass will be the same.
V.O. Kremnev, L.U. Shpilberg, A.V. Timoshchenko, O.V. Hylienko, Ye.V. Timoshchenko
Кераміка: наука і життя pp 21-28; doi:10.26909/csl.4.2018.3

Abstract:A brief historical overview of the creation of technology of the materials based on staple basalt fibers is given. The primary role in creating the technology of the Institute for Problems of Materials Science of the National Academy of Sciences of Ukraine, a number of academic and sectoral institutes is noted. Thermophysical characteristics of basalt fibrous materials and basalt-bentonite products are given. For fibrous materials based on BSTF, the following dependences are given: thermal conductivity coefficient, as a function of density and temperature; optimal density of the heat insulating canvas, characterized by a minimum coefficient of thermal conductivity, as a function of temperature; the compaction factor of the canvas, as a function of temperature. The description of the multistage duplex process of the BSTF production is given. The block diagrams of the production processes for soft and semi-rigid products are considered. The stages of production at which natural gas is consumed are highlighted. A high proportion of the cost of energy in the cost of finished products reaches 70 - 80% is given. The results of experimental-industrial tests of the main gas-using equipment - melting furnaces, gas burners, tunnel dryer are given. Two methods were used to determine specific energy consumption. The maximum of the values determined by different methods was chosen as the defining value of energy consumption. There is a non-stationary nature of the equipment. The results of the analysis are presented in the form of specific indicators of natural gas consumption per unit of finished product, and heat per 1 kg of evaporated moisture. Thus, the specific consumption of natural gas per 1 kg of BSTF, for the existing technology, is 4,8 standard cubic meter, and the release of 1 cubic meters basalto-bentonite plate - 300 standard cubic meter. The basic heat engineering principles are formulated, which will allow a multiple increase in the energy efficiency of heat technologies, among them - the reduction of losses through the structures of equipment; loss reduction with high-temperature combustion products; intensification of heat and mass transfer processes in equipment components and elimination of unorganized gas exchange of internal technological volumes.
Y.V. Kornienko, P.M. Magaziy, K.O. Gatilov, R.V. Sachok
Кераміка: наука і життя pp 15-20; doi:10.26909/csl.4.2018.2

Abstract:The temperature field of firm crystal-amorphous structures receiption from liquid systems in the fluid bed is explored. The stable conducting terms of process are certain. Previous studies have shown that increasing the irrigation density increases the probability of formation of agglomerates, which causes a decrease in temperature; therefore, it is advisable to measure the temperature field in the environment of the dispersant and compare it with the values of temperatures at the characteristic point, according to which the regulation of the flow of liquid phase to the granulator is carried out. The objective of the experimental research was to determine the change of the temperature field in disperse systems in obtaining crystalline-amorphous solid structures in a fluidized-bed apparatus. In case of an increase in the amount of heat flow, an adequate increase in the flow of liquid phase occurs. This results in the local overturning of solid particles and, as a result, the formation of large aggregates and loss of quality of fluidization. To eliminate this disadvantage it is advisable to create conditions for uneven distribution of the coolant speed. In the downstream right and left fluxes, the coolant speed should not exceed the rate of gas filtration through the material. In the left upward flow, in which the direction of motion of the granular material is opposite to the direction of the vector of the linear velocity of the dispersed droplets of the liquid phase, it is expedient to increase the flow of the coolant in a direction that coincides with the downstream flow. To verify these provisions, it is expedient to conduct a study of the continuous process of formation of solid multilayer composites.
V.м. Pazyuk
Кераміка: наука і життя pp 7-14; doi:10.26909/csl.4.2018.1

Abstract:The results of experimental studies of the drying of capillary-porous materials of spherical shape from the influence of the temperature of the heat carrier are given.Spherical granules with a diameter of 2,2 mm were taken to determine the rational modes of drying of capillary-porous materials. For a better evaluation of the nature of the drying process, experimental design studies were carried out on a convective drying stand in an elementary layer.The program of automatic collection and processing of information allows obtaining data on changes in the mass and temperature of the sample during the removal of moisture, and also performs calculations of kinetics of drying in absolute and relative coordinates. This makes it possible to obtain and compare the kinetic and velocity characteristics of colloid capillary-porous materials drying faster, more accurately and reliably.By the method of Krasnikov V.V. the kinetics of drying of capillary-porous materials of spherical shape with a diameter of 2,2 mm with construction of a generalized drying curve with determination and calculation of drying coefficients is considered.The generalized curve of drying rate is constructed and obtained, which allows us to generalize the process of drying of a capillary-porous spherical material. Also, get the formula and determine the overall length of the drying process through the drying rate for each heat treatment.When comparing the values of the process length obtained by experimental studies and determined by the calculations, the experimental error from the calculation does not exceed 3%.The analysis of heat-mass-exchange processes of drying by means of calculations of temperature coefficient b, Rebinder Rb criterion, heat flow q and coefficient of heat transfer α from the influence of heat carrier temperature has been carried out.
O. V. Savvova, V. L. Topchyi, S. A. Riabinin
Кераміка: наука і життя pp 34-39; doi:10.26909/csl.3.2018.5

Abstract:Проаналізовано основні напрямки розробок літійалюмосилікатних склокерамічних матеріалів та встановлено перспективність впровадження у військовій галузі в якості захисних термостійких бронеелементів, які експлуатуються в умовах високошвидкісних механічних навантажень та дії високої температури. Метою даної науково-практичної роботи є дослідження термічних властивостей літійалюмосилікатних склокерамічних матеріалів. Досліджено вплив структури розроблених склокерамічних матеріалів на їх температурний коефіцієнт лінійного розширення та встановлено визначальний вплив фазового складу на термічні властивості. Розроблено модельні літійалюмосилікатні стекла та синтезовано склокерамічні матеріали на їх основі. Встановлено, що визначальним фактором при визначенні впливу фазового складу на температурний коефіцієнт лінійного розширення дослідних матеріалів є наявність та вміст β-сподумену у їх складі. Застосування як елементів індивідуального бронезахисту розроблених склокристалічних матеріалів дозволить знизити термоудар, який виникає при зіткненні снаряду з бронематеріалом, що дозволить їх застосовувати в якості матеріалів для бронеелементів.
O. V. Savvova, O. V. Babich, O. I. Fesenko
Кераміка: наука і життя pp 14-22; doi:10.26909/csl.3.2018.2

Abstract:Визначена актуальність створення інноваційних резорбційних біосумісних склокерамічних матеріалів для кісткового ендопротезування з високими механічними властивостями та значним рівнем біоактивності на основі кальційсилікофосфатних стекол. Розроблено методологічний підхід до розробки біоактивних резорбційних склокерамічних матеріалів для кісткового ендопротезування. Теоретично обґрунтовано напрямки одержання біосумісних неорганічних матеріалів для заміщення дефектів кісткової тканини та основні принципи їх створення. Встановлено комплекс сучасних взаємодоповнюючих методів дослідження необхідних для визначення основних фізико-хімічних та експлуатаційних властивостей даних матеріалів. Визначено особливості проектування складів та структури склокерамічних матеріалів для кісткового ендопротезування та комплекс необхідних експлуатаційних властивостей. Розроблено біоактивні склокерамічні матеріали на основі кальційсилікофосфатних стекол, які характеризуються оптимальними фізико-хімічними, медикобіологічними властивостями та можуть бути використані як імплантати для заміни статично та динамічно навантажених ділянок кістки у щелепно-лицевій хірургії.