Proceedings of the National Academy of Sciences of Belarus, Physical-Technical Series / Известия Национальной академии наук Беларуси. Серия физико-технических наук
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«ИНДУСТРИЯ 4.0»: ОТ ИНФОРМАЦИОННО-КОММУНИКАЦИОННЫХ И АДДИТИВНЫХ ТЕХНОЛОГИЙ К САМОВОСПРОИЗВЕДЕНИЮ МАШИН И ОРГАНИЗМОВ
Get PDFAn analysis of the state and prospects of development of additive technologies for computer-aided manufacturing has been carried out. This analysis allowed demonstrating a new paradigm of computer-aided manufacturing evolution – the transition to self-reproduction of machines and their parts, as well as organisms. A diagram of logical connections in the process of additive manufacturing has been proposed, which is a state machine that can be used to build a 3D printer enabling to “grow” products of complex shapes and structures, as well as for additive synthesis of its composite material. Prospective approach, considering additive methods such as synergetic energy technology, ensuring the self-organization of surface phenomena in the formation of structures of layers of different materials has been developed. It is proposed on the basis of the approach to choose sources of energy and material defining discrete or continuous technological environment of the additive processing method. Conditions for stabilization of the thickness of formed layers associated with processes of self-organization of surface phenomena and design features of products have been discussed.Проведен анализ состояния и перспектив развития аддитивных технологий компьютеризированного производства, позволивший показать новую парадигму его эволюции – переход к самовоспроизведению машин и их частей, а также организмов. Предложена диаграмма логических связей в процессах аддитивного производства, представляющая собой конечный автомат, которая может использоваться как для построения 3D-принтера, осуществляющего «выращивание» изделия сложной формы и структуры, так и для аддитивного синтеза его композиционного материала. Рекомендован подход, который определяет аддитивные методы как синерготехнологии, обеспечивающие самоорганизацию поверхностных явлений. На основании подхода выбираются источники энергии и материала для технологий послойного синтеза изделий. Стабилизация толщины формируемых слоев связана с процессами самоорганизации поверхностных явлений и конструктивными особенностями изделий.
ВКЛАД ПОНДЕРОМОТОРНЫХ ФАКТОРОВ В РЕАЛИЗАЦИЮ ЭЛЕКТРОПЛАСТИЧЕСКОЙ ДЕФОРМАЦИИ
Get PDFTheoretical aspects of the implementation of electroplastic deformation for dynamic pinch-effect at elastic-plastic deformation of metals with the participation of self-magnetic field of current are considered. The redistribution of magnetic field intensity H in the surface layers of metal leads to ponderomotive effects in the form of dynamic pinch effect, which in addition to the electron-plastic action of the pulse current leads to a compression of the sample intrinsic magnetic field and the excitation of elastic vibrations of the skeleton of the crystal lattice, with a repetition frequency of current pulses at the front of their rise. Dynamic pinch effect creates ultrasonic vibration of the lattice system, thus changing the kinetics, and induced plastic deformation due to the increase of the oscillation amplitude of rectilinear dislocations and periodic changes of the position of the dislocation loops with a higher probability of detachment of dislocations from stoppers. At deformation above the yield limit, due to the pinch effect, magnetic field of a current diffuses into crystal, thus the rate of diffusion depends on the conductivity of the metal and the frequency of the current. At the same geometry of the samples, the pinch effect is stronger for materials with high electrical conductivity. For practical use of the technology of electroplastic deformation, especially in the processing of metals by pressure by drawing, rolling and so on, it is necessary to consider physical conditions of the creation of the ponderomotive effects in relation to particular technologically important materials.
АНАЛИЗ И ПРОГНОЗИРОВАНИЕ РАЗВИТИЯ РЫНКА КОСМИЧЕСКИХ УСЛУГ
Get PDFCurrently space industry development sets key macro-economic indicators in the country. It influences on such indicators as value and growth rates of GDP, improves competitiveness of industrial products and whole economies. The paper contains information about main areas of using space activity results in military and civilian spheres, the analysis of the current conditions and prospects of development of the world market of space services aimed at meeting peoples’ needs. The authors create a mathematical model for estimating and predicting market capacity given actual trends of reducing space service cost in the world in order to assess development of equipment and technologies in the field of space activities. The paper contains the forecast of changes in the volume of purchases and capacity of space service market until 2026.В настоящее время уровень развития космической промышленности задает важнейшие макроэкономические показатели развития в стране, в том числе влияет на значение и темпы роста валового внутреннего продукта, определяет конкурентоспособностьвыпускаемой промышленной продукции и в целом национальной экономики. В статье определены основные области применения результатов космической деятельности, в том числе в гражданской сфере, проведен анализ современного состояния и перспектив развития мирового рынка космических услуг, направленных на удовлетворение потребностей населения. Для оценки развития техники и технологий в области космической деятельности авторами разработана математическая модель оценки и прогнозирования емкости рынка при выявленных тенденциях снижения стоимостикосмических услуг в мире. Построен прогноз изменения объема покупок и емкости рынка космических услуг до 2026 г
ПРИМЕНЕНИЕ МЕТОДА ПРОСВЕЧИВАЮЩЕЙ ЭЛЕКТРОННОЙ МИКРОСКОПИИ ДЛЯ ОЦЕНКИ ФОРМИРОВАНИЯ ИОННО-ЛУЧЕВЫХ МНОГОСЛОЙНЫХ НАНО- СТРУКТУРНЫХ ПОКРЫТИЙ НА ОСНОВЕ ХРОМА
Get PDFThe aim of the work is to study a mechanism of formation of a monolayer in a multilayered ion beam nanostructured coating by transmission electron microscopy (TEM), and a model of formation and growth of a monolayer by ion beam sputtering of target substrate with an ion assisting. To investigate the mechanism of formation and growth of monolayer in the coating a technique of sample preparation was developed for further study using electron microscopy Tescan MIRA (Czech Republic), allowing to obtain image surface of an object with high resolution, especially at low accelerating voltages. For the study of thin films, transmission electron microscopy is used much more frequently than scanning, so a console has been designed that allows to obtain images in the passing electrons – TE detector for study by scanning transmission electron microscopy (STEM – Scanning Transmission Electron Microscopy). During study of monolayers by transmission electron microscopy using a TE detector, a mechanism of the formation of monolayer in multilayer ion-beam nanostructured coating has been proposed, consisting of the following steps: the adsorption of chromium particles on the substrate surface; surface diffusion to the stage of a screw dislocation; 2D-growth of chromium monolayer (2D-formation terraces) of 2D-islands; 2D→3D transition – the transition to three-dimensional island growth mode (3D-growth) by the mechanism of Stransky – Krastanow. The model of formation and growth of monolayer under ion-beam sputtering of a target with ion-assisted substrate has been developed
ПРИМЕНЕНИЕ ТРЕКОВЫХ МЕМБРАН В ПРОЦЕССАХ ПРЯМОГО И ОБРАТНОГО ОСМОСА
Get PDFA method of design of polyethylene terephthalate track membranes with asymmetric (conic) pores shaped by ion-track technology was considered. The method consists of two main stages: irradiation by swift heavy ions and one-sided etching of latent tracks. The shape and dimensions of individual pores of track membranes were defined by scanning electron microscopy of surfaces and cross-sections of membranes prepared with different etching times. Based on these results, time dependencies of cone bases and apex diameters of asymmetrical pores were determined. The possibility of the membranes application for direct and reverse osmosis was determined according to the results of investigations asymmetric track membranes with conic shape pores by means of measuring of hydrophility, air and water performance. Based on the analysis of tensile strength under loading with slowly changing pressure, the maximum pressure value that the membrane could stare was determined, as well as the dependence of the strength characteristics on the samples porosity. Simulation study of osmotic processes in NaCl solution efficiency of the track membranes for the direct and reverse osmosis was demonstrated and the influence of membrane parameters on their performance and the degree of water purification was showed.
ДЕФОРМАЦИОННОЕ ИЗМЕЛЬЧЕНИЕ ЗЕРЕН МИКРОСТРУКТУРЫ ЛЕГИРОВАННЫХ СТАЛЕЙ ПРИ НЕСТАЦИОНАРНОЙ ИНТЕНСИВНОЙ ПЛАСТИЧЕСКОЙ ДЕФОРМАЦИИ ВЗРЫВОМ
Get PDFDependence of grain size of alloyed high-strength steels of austenitic, bainitic, maraging classes on temperature and degree of deformation at non-stationary intensive plastic deformation by explosion has been studied. A model which enables to calculate dispergating limit value considering dependence of coefficient of grain-boundary diffusion on degree of deformation and temperature is constructed. The results of calculations by the offered formula and their comparing to experimental data show satisfactory coincidence. A rejection is 3–5%. It is set that the intensive growing shallow under the action of high-speed flowage the explosion of alloyed high-strength steels takes place at the degrees of deformation 20–30%. Increase of degree of deformation to 30–40% does not cause the change of size of grain. At deformations more than 40–50% the accumulated flowage causes additional local warming-up of material and development of recrystallizational processes, sizes of grain increase as a result. At deformations higher 50–60% appearances of cracks in materials is possible
ДИНАМИЧЕСКАЯ МОДЕЛЬ СКОРОСТНОЙ ФИЛЬТРАЦИИ ТЕПЛОНОСИТЕЛЯ В СЛОЕ МИКРОТВЭЛОВ
Get PDFIt is shown that mathematical hydrodynamic models of micro fuel beds can’t describe viscous and inertial effects truly. The filtration equations obtained by averaging the equation of viscous fluid motion over an elementary volume and containing the so-called viscous term are valid only for the infinite porous medium. Using these equations and no-slip condition on the impermeable ends of bed leads to discrepancy between estimated and observed data. The constructed rapid coolant filtration model is based on the ideal fluid motion laws with a volume interphase interaction force, which is represented as a divergence of a tensor with potential and vortex components. In this case, the potential component reflects the contribution of the resistance forces to the normal pressure of the coolant and is a “hidden” parameter – the reason for experimental data spread. Using the model, dynamics of the coolant flow at the inlet and outlet of the fuel bed is investigated and the matching conditions for velocity and pressure vector are determined. These conditions make it possible to relate the filtration equation and viscous fluid motion equation on the bed permeable boundaries. Due to dominance of inertia forces at entrance and exit of the bed, the stream is refracted: at the inlet towards the normal to the bed boundary, and at the exit towards the tangent. Accounting for this effect the optimize fuel bed contours in terms of thermal physics and neutron physics will be obtained
ОПТИМИЗАЦИЯ ГЕОМЕТРИИ ПЛОСКИХ ПРУЖИН С УЧЕТОМ КОНСТРУКТИВНЫХ ОСОБЕННОСТЕЙ И ХАРАКТЕРА ДИНАМИЧЕСКОГО НАГРУЖЕНИЯ
Get PDFA geometry optimization method based on use of macros for finite-element analysis program ANSYS 10 ED / LS-DYNA was developed for system of series-connected flat springs used as elastic elements of catapult for launching unmanned aerial vehicles. Optimization criterion in this case is the condition of the maximum stroke of both flat springs with the minimum deviation from the symmetrical form with respect to spring midpoints. Dynamic optimization problem of compression and relaxation of flat spring system was reduced to quasi-static problem of system pre-compression and high-velocity dynamic problem of its relaxation, and it significantly reduced solution time. Solution to the first part of the problem was carried out by means of Implicit Solver of ANSYS 10 ED / LS-DYNA. Solution to the second part of the problem was obtained by means of Explicit Solver of ANSYS 10 ED / LS-DYNA based on previous part results. It was determined that optimum system in terms of stroke and deviations of symmetry of flat springs consists of identical springs which are symmetrical relative to section middles.
СООТНОШЕНИЕ ДИНАМИЧЕСКОЙ И СТАТИЧЕСКОЙ ТВЕРДОСТИ МЕТАЛЛОВ
Get PDFProblems of measurement of hardness by the dynamic indentation method are discussed. It is shown that an excess of dynamic hardness over static one can be described by the coefficient, which is a function of material properties and test conditions.In framework of the dislocation theory the influence of strain rate on hardness value is shown, and the difference in ratio between static and dynamic hardness can be explained by different crystal structure of materials.With the help of the device IPM-1K the experimental diagrams of dynamic loading of various metals: steel, aluminum, bronze, brass, copper, titanium were obtained. A method of calibration of dynamic hardness testers for calculation of the Brinell hardness without using standard hardness test blocks was proposed.Рассматриваются вопросы измерения твердости методом ударного вдавливания индентора. Показано, что превышение динамической твердости над статической может быть описано с помощью коэффициента динамичности, представляющего собой функцию свойств материала и условий испытаний. В рамках дислокационной теории показановлияние скорости деформации на величину твердости, при этом отличие значений коэффициента динамичности объясняется разной кристаллической структурой исследуемых материалов. С помощью прибора ИПМ-1К получены экспериментальные диаграммы динамического нагружения различных металлов: стали, алюминия, бронзы, латуни, меди, титана. Предложена методика калибровки динамических твердомеров для расчета статической твердости по Бринеллю без использования эталонных мер твердости