Перегляд за Автор "Mygushchenko, R. P."
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Документ Changes in the structural state and properties of vacuum-arc coatings based on high-entropy alloy TiZrHfNbTa under the influence of nitrogen pressure and bias potential at deposition(2018) Sobol, O. V.; Andreev, A. A.; Mygushchenko, R. P.; Gorban, V. F.; Stolbovoy, V. A.; Meylekhov, A. A.; Subbotina, V. V.; Kovteba, D. V.; Zvyagolsky, A. V.; Vuets, A. E.Complex studies have been carried out on the effect of nitrogen pressure and the negative bias potential on the structure and properties of vacuum-arc nitride coatings based on the high-entropy alloy TiZrHfNbTa. It is defined that the change in pressure during deposition (in the range 0.01...4 mTorr) mainly affects the nitrogen atoms content in the coating. The feed of a negative bias potential to the substrate (Ub = -50...-250 V) makes it possible to control the content of the metallic component using the effect of selective sputtering of atoms in the formation of coatings. Determined, that as the pressure increases the structural state associated with the predominant growth orientation (axial texture) of the crystallites changes. The texture changes in the sequence [311] → [311] + [111] → [111] with increasing pressure for a six-element (TiZrHfVNbTa)N nitride and the texture state changes in the sequence [110] → [110] + [111] → [111] for a five-element (TiZrHfNbTa)N nitride. It is shown that the presence of a bi-textured state in the coating makes it possible to achieve an ultrahard state with a hardness exceeding 50 GPa.Документ Comparative analysis of electrical and thermal control of the lining state of induction apparatus of copper wire manufacture(НТУ "ХПИ", 2018) Zolotaryov, V. M.; Shcherba, M. A.; Belyanin, R. V.; Mygushchenko, R. P.; Kropachek, O. Yu.This article is intended to develop a technique for monitoring the lining state of induction channel furnaces for melting oxygen-free copper by monitoring changes in the distribution of thermal fields in their lining and carrying out a comparative analysis of the developed technique with the existing one that controls the electrical resistance of the melting channel of the furnaces. For carrying out the research, the theories of electromagnetic field, thermodynamics, mathematical physics, mathematical modeling based on the finite element method were used. A technique for diagnosing the lining state of the induction channel furnaces for melting oxygen-free copper has been developed, which makes it possible to determine the dislocation and the size of the liquid metal leaks by analyzing the temperature distribution over the body surface both the inductor and the furnace. The connection between the temperature field distribution on the surface of the furnace body and the dislocation and dimensions of the liquid metal leaks in its lining is determined for the first time. Using the proposed technique will allow to conduct more accurate diagnostics of the lining conditions of the induction channel furnaces, as well as to determine the location and size of the liquid metal leaks, creating the basis for predicting the working life of the furnace.Документ The Effect of Constant and High Voltage Pulse Bias Potentials on the Structure and Properties of Vacuum-Arc (TiVZrNbHf)Nₓ Coatings(Sumy State University, 2018) Sobol, O. V.; Postelnyk, A. A.; Mygushchenko, R. P.; Gorban, V. F.; Stolbovoy, V. A.; Zvyagolskiy, A. V.The effect of constant (Ub) and high voltage pulse (Uip) bias potentials supplied to the substrate during condensation, on the structure and properties of vacuum-arc (TiVZrN-Hf)Nх coatings has been studied. It has been determined that the number and size of the drop phase decreases with increasing Ub. The use of Uip promotes a more uniform growth in the coating volume. It is shown that due to the increase of Ub from 0 to 200 V in nitride coatings of high entropy alloys, it is possible to change the growth texture [100] to [111]. This results in increased hardness from 32 GPa to 49 GPa. The supply of high voltage potential in a pulse form leads to a relative decrease in the average size of crystallites and the formation of a bi-texture state. Conditions and mechanisms of the preferential crystallites orientation (axial texture) of vacuum arc (TiVZrNbHf)Nх coatings and texture influence on mechanical properties have been discussed.Документ The effect of the substrate potential during deposition on the structure and properties of the binanolayer multiperiod composites (TiAlSi)N/MeN (Me – Zr, Nb, Cr, Mo)(2018) Sobol, O. V.; Andreev, A. A.; Mygushchenko, R. P.; Stolbovoy, V. A.; Postelnyk, A. A.; Meylekhov, A. A.; Dolomanov, A. V.; Rebrova, Ye. M.It is proposed to use the multiperiod binanolayer composites (TiAlSi)N/MeN (Me-Zr, Nb, Cr, Mo) for controlling the structure, stress state and mechanical properties of a multi-element nitride (TiAlSi)N. The deposition of the layers was carried out by the method of vacuum-arc evaporation at different bias potentials on the substrate Ub = -110 and -200 V. It has been determined that mononitrides with a high Me-N binding energy in the binanolayer composite determine the crystallite growth in thin (nanometer) layers. The growth texture is formed in composites containing mononitrides based on transition metals with a relatively small atomic mass (Cr, Mo) at Ub = -110 V. The growth texture is formed at a larger Ub = -200 V when dealing with mononitride based on heavy metal (Zr). The greatest hardness is achieved in textured materials deposited at Ub = -200 V. This is typical both for a monolayer multi-element nitride (TiAlSi)N (hardness is 42.5 GPa) and for multiperiod nanolayer composites based on it (the highest hardness is 47.9 GPa for a composite (TiAlSi)N/ZrN).Документ Electromechanical transient processes during supply voltage changing in the system of polymer insulation covering of the current-carrying core ofultra high voltage cables(НТУ "ХПИ", 2018) Zolotaryov, V. M.; Shcherba, M. A.; Belyanin, R. V.; Mygushchenko, R. P.; Korzhov, I. M.The article is devoted to the analysis of the electromechanical transient processes in a system of three frequency-controlled electric drives based on asynchronous motors that control current-carrying core motion, as well asto the study of the effect of such processes on the modes applying three-layer polymer insulation to the current-carrying core. The study was conducted based on the concepts of electromechanics, electromagnetic field theory, mathematical physics, mathematical modeling. A mathematical model has been developed to analyze transients in an electromechanical system consisting of three frequency-controlled electric drives providing current-carrying core motion of ultra-high voltage cables in an inclined extrusion line. The coordination of the electromechanical parameters of the system drives has been carried out and the permissible changes in the supply voltage at the limiting mass while moving current-carrying core of ultra-high voltage cables with applied polymer insulation have been estimated. For the first time it is determined that with the limiting mass of the current-carrying core, the electromechanical system allows to stabilize the current-carrying core speed with the required accuracy at short-term decreases in the supply voltage by no more than 27 % of its amplitude value. It is also shown that this system is resistant to short-term increases in voltage by 32 % for 0.2 s. Using the developed model, it is possible to calculate the change in the configuration and speed of the slack current-carrying core when applying polymer insulation, depending on the specific mass of the current-carrying core per unit length, its tension atthe bottom, the torque of the traction motor and the supply voltage to achieve stable operation of the system and accurate working of the set parameters.Документ The Influence of Layers Thickness on the Structure and Properties of Bilayer Multiperiod Coatings Based on Chromium Nitride and Nitrides of Transition Metals Ti and Mo(Sumy State University, 2018) Sobol, O. V.; Meylekhov, A. A.; Mygushchenko, R. P.; Postelnyk, A. A.; Tabaza, Taha A.; Al- Qawabah, Safwan M.; Gorban, V. F.; Stolbovoy, V. A.The influence of the layers thickness of bilayer multi-period coatings of the CrNx/MoNx and CrNx/TiNx systems on their phase-structural state, substructure, stress-strain state and mechanical properties was studied using methods of precision structural analysis in combination with computer simulation of implantation processes during particle deposition. It is established that a two-phase structure of CrN and-Mo2N phases of the structural type NaCl is formed in the multi-period coatings of the CrNx/MoNx system with a nanometer thickness of the layers. Because of the small difference in periods (less than 0.5 %) for Λ = 20 nm, the layers form a coherent interlayer interface. The use of small Ub – 20 V during deposition makes it possible to avoid significant mixing at interlayer (interphase) boundaries even at the smallest Λ = 10 nm. Nitride layers formed under conditions of vacuum arc deposition are under the action of compressive stresses. In the СrNх/TiNх system, because of the relatively large discrepancy between periods (more than 2.5 %), during the formation of the same structural components in the layers (CrN and TiN phases of the structural type NaCl), the epitaxial growth with period adjusting does not occur, even for the smallest Λ = 10 nm. The action of the deformation factor at the interphase boundary allows achieving an ultrahard state (with a hardness of about 50 GPa), which causes a relatively low friction coefficient. The obtained results on the formation of phase-structural states with the nanoscale thickness of layers of multi-period nitride coatings are explained from the position of minimization of surface energy and deformation energy.Документ Metrological study of the effect of temperature on the dissociation of acetic acid(Національний технічний університет "Харківський політехнічний інститут", 2023) Mygushchenko, R. P.; Volobuyev, M. M.; Asieieva, I. V.; Kropachek, O. Yu.; Baliev, V. M.This article is devoted to the study of the dissociation reaction of acetic acid at a temperature change in the range from room (20 °C) to 75 °C. In the course of research, the methods were considered, the classification of the considered methods was carried out, and the methodology of the experiments was formulated. The selected technique reflects the express measurement of the hydrogen pH indicator using a portable pH-meter. Experiments were carried out in laboratory conditions – Lincoln Park, Chicago, USA. Acetic acid with a concentration of 6 mol/l was chosen as the basis. By adding a distilled water, a base concentration of 1 mol/l was obtained. Nodal temperature points were selected for measurements (four points in the temperature range of 20 °C – 75 °C); five experimental samples of acetic acid (1 mol/l) were formed; the analysis of the measurement results at nodal points was carried out for the accuracy of the measurement results of five test samples of acetic acid using first- and second-order statistical moments (mathematical expectation and variance); accuracy characteristics of experimental data (instrumental and methodical errors) were estimated. Research samples (acetic acid samples) were brought to the nodal points with a positive temperature gradient using a steam bath. The measurement error estimate was determined by the accuracy class of the device and was 0.1%. The obtained pH values were converted to the number of hydrogen cations, followed by the determination of the degree of dissociation and the dissociation constant. These determinations were carried out under the condition of ensuring chemical equilibrium. The nature of the behavior of the degree and constant of dissociation when the temperature of the test samples changes is clearly non-linear. In the course of research, the main measurement errors were established, the main of which is the nonlinearity of the transformation. Quantitative values of nonlinearity errors were determined by the method of measurements with multiple observations using the Student's correction factor. The article provides conclusions based on the results of research and presents the prospects for temperature correction of pH-meters to eliminate the temperature component of the error of pH-meters.Документ Minimization of errors in discrete wavelet filtering of signals during ultrasonic measurements and testing(Національний науковий центр "Інститут метрології", 2021) Taranenko, Yu.; Mygushchenko, R. P.; Kropachek, O. Yu.; Suchkov, G. M.; Plesnetsov, Yu.Error minimizing methods for discrete wavelet filtering of ultrasonic meter signals are considered. For this purpose, special model signals containing various measuring pulses are generated. The psi function of the Daubechies 28 wavelet is used to generate the pulses. Noise is added to the generated pulses. A comparative analysis of the two filtering algorithms is performed. The first algorithm is to limit the amount of detail of the wavelet decomposition coefficients in relation to signal interference. The minimum value of the root mean square error of wavelet decomposition signal deviation which is restored at each level from the initial signal without noise is determined. The second algorithm uses a separate threshold for each level of wavelet decomposition to limit the magnitude of the detail coefficients that are proportional to the standard deviation. Like in the first algorithm, the task is to determine the level of wavelet decomposition at which the minimum standard error is achieved. A feature of both algorithms is an expanded base of discrete wavelets ‒ families of Biorthogonal, Coiflet, Daubechies, Discrete Meyer, Haar, Reverse Biorthogonal, Symlets (106 in total) and threshold functions garotte, garrote, greater, hard, less, soft (6 in total). The model function uses random variables in both algorithms, so the averaging base is used to obtain stable results. Given features of algorithm construction allowed to reveal efficiency of ultrasonic signal filtering on the first algorithm presented in the form of oscilloscopic images. The use of a separate threshold for limiting the number of detail coefficients for each level of discrete wavelet decomposition using the given wavelet base and threshold functions has reduced the filtering error.Документ Mixing on the Boundaries of Layers of Multilayer Nanoperiod Coatings of the TiNх/ZrNх System: Simulation and Experiment(Sumy State University, 2017) Sobol, O. V.; Meylekhov, A. A.; Mygushchenko, R. P.; Postelnyk, A. A.; Sagaidashnikov, Yu. Ye.; Stolbovoy, V. A.Using the complex of methods for attestation of the structural state in combination with computer simulation and measurement of mechanical properties (hardness), the influence of the period Λ on the mixing process on the interlayer boundaries of multilayer coatings TiNх/ZrNх is studied. The formation of two phases (TiN and ZrN) with one type of crystal lattice (structural type NaCl) is identified in the layers of multiperiodic compositions TiNx/ZrNx with a period of Λ = 20 ... 300 nm. At Λ = 10 nm, the formation of a solid solution (Zr, Ti)N, as well as a small volume of the TiN phase is revealed on XRD spectras. The presence of TiN component is due to the larger initial value of the layer based on titanium nitride. To explain the results obtained, the results of computer simulation of damage at the atomic level during bombardment by ions accelerated in the Ub field are used. The critical thickness of mixing (about 7 nm) in the TiNx/ZrNx system is determined upon condition that Ub = – 110 V. It is established that a decrease in the period from 300 to 20 nm leads to increase in hardness. The highest hardness of 44.8 GPa corresponds to the superhard state. It is established that the critical thickness of radiation-stimulated defect formation has a significant effect on the stress-strain state and hardness of coatings with a small Λ ≈ 10 nm. In this case, relaxation of the stress-strain compression state occurs and the hardness decreases. However, the formation of a solid solution, while retaining part of the unreacted layer of titanium nitride at Λ = 10 nm, makes it possible to obtain an ultrahigh (44.8 GPa) hardness of the coating.Документ Physical principles of non-contact ultrasonic frequency sensors creation for the study of nanocrystalline ferromagnetic materials(Сумський державний університет, 2018) Plesnetsov, S. Yu.; Mygushchenko, R. P.; Petryschev, O. N.; Suchkov, G. M.; Khrypunova, A. L.A mathematical model is developed to determine the force impacts that are formed when the electro-magnetic field is transformed into a field of ultrasonic oscillations in the skin layer of an electrically conductive ferromagnetic material of an anisotropic magnetic permeability. The main factors determining the excited acoustic field with allowance for permissible limitations are established. It is shown that the main contribution to the acoustic vibrations energetics is made by the magnetostrictive component of the skin layer material, in which the high-frequency electromagnetic field is transformed into an acoustic field.Документ Powerful sources of pulse high-frequency electromechanical transducers for measurement, testing and diagnostics(НТУ "ХПИ", 2018) Plesnetsov, S. Yu.; Petrishchev, O. N.; Mygushchenko, R. P.; Suchkov, G. M.; Sotnik, S. V.; Kropachek, O. Yu.Development of powerful current radio pulses generators (CRPG) for powering high-frequency electromechanical transducers based on IGBT transistors. To carry out the research, the statements of the magnetic and electromagnetic fields interaction with electric and ferromagnetic material, electric circuits, structure of radio electronic devices theory were used. The main provisions for creating powerful broadband generators for powering electromechanical transducers based on IGBT transistors are determined. It is shown that the generators intended for use in measurements, testing and diagnostics should provide adjustment of the frequency and duration of the output current pulses, and also provide current in the transducer inductor of several hundred amperes. The connection between the power frequency of the resonant electromechanical transducer and the gap between the transducer and the surface of the metal being diagnosed is established. A CRPG variant for powering electromechanical transducers in the frequency range 1 ... 3 MHz and the duration of current pulses of 1 ... 20 periods of the filling frequency is developed and manufactured. The peak current in the inductor of a high-frequency electromechanical transducer has reached 450 A. For the first time, the possibility of using powerful IGBT transistorsin electronic devices working in a key mode in push-pull circuits for feeding high-frequency electromechanical transducers is shown. Using the resultsobtained will allow the creation of new instruments for measurement, control and diagnostics with wider characteristics.Документ Reliability of the Rubber Tube of Automotive Hydraulic Braking System Under Fatigue Failures Considering Random Variation of Load and the Process of Aging of Material(Islamic Azad University, Iran, 2019) Larin, O. O.; Potopalska, K. E.; Mygushchenko, R. P.This paper presents the approach for the assessing of the operational reliability of a multi-layer thick-walled tube made of rubber with textile reinforcement. The analysis of the fatigue accumulation process is carried out within the framework of the concept of the continuum mechanics of damage. The mathematical model, which takes into account the accumulation of damages in case of a random spread of the strength characteristics of the material, as well as the process of stochastic aging for the elastomeric matrix of the composite and possible random variation of the workload has been developed. In this case, the aging process is modelled as a reduction of the endurance limit of the material. In this paper, the mean equivalent strains of the tube and their possible statistical variation in operation have been investigated on the basis of the finite element method. To solve the above problems, a submodeling method has been employed in this work. The probability of non-failure operation of the tube has been determined using the methods and models proposed. The influence of the rate of the aging process on the lifetime of the tube has been estimated.Документ Simulation of Electromagnetic Conversion Process Under Torsion Waves Excitation(Інститут електродинаміки НАН України, 2018) Plesnetsov, S. Yu.; Petrishchev, O. N.; Mygushchenko, R. P.; Suchkov, G. M.Mathematical simulation and calculation of electromagnetic fields in the electromagnetic-acoustic transducer of rational design are performed under non-dispersive torsional waves excitation in tubular electrically conductive ferromagnetic hollow rods of small diameter, taking into account spatial, frequency, energy and material factors. The results of the research can be used to simulate and construct exciting EMATs for measuring, monitoring, and diagnostic equipment in the energy, nuclear, chemical and other industries in view of ultrasonic studies of ferromagnetic tubular products.Документ Simulation of Electromagnetic Conversion Process Under Torsion Waves Excitation(Інститут електродинаміки НАН України, 2018) Plesnetsov, S. Yu.; Petrishchev, O. N.; Mygushchenko, R. P.; Suchkov, G. M.Mathematical modeling of the electromagnetic-acoustic transducer (EMAT) for excitation of nondispersive torsional waves in tubular electrically conductive ferromagnetic hollow rods of small diameter is performed taking into account all the factors that determine the design of the EMAT. The solutions of the differential equation for the values of the electromagnetic fields formed by the high-frequency coil of the device in the gap between the transducer and the tubular ferromagnetic product are found. The results of the research can be used to simulate and design exciting EMATs for measuring, monitoring, and diagnostics in the energy, nuclear, chemical and other industries for ultrasonic test of ferromagnetic tubular products.Документ Statistical Estimation of Residual Strength and Reliability of Corroded Pipeline Elbow Part Based on a Direct FE-Simulations(Serbian Society for Computational Mechanics, 2018) Larin, O. O.; Potopalska, K. E.; Mygushchenko, R. P.In this paper, the assessment of the effect of a corrosion defect, which is developing over time on the working capacity of the pipeline elbow, has been carried out. Corrosion damage models explicitly as volumetric defect on the out surface of the pipeline elbow. The zones on the damaged section of the pipeline on which the maximum stresses are localized has been defined using the finite element analysis. The estimation of the characteristics of the deformed state of a design with defect is analysed with the framework of computer simulations. On the basis of the obtained results, the probabilistic characteristics of the stresses and plastic strains have been approximated as a function of internal pressure and corrosion defect depth, such as mean value, coefficients of variation and asymmetry. Probability densities function of plasticity appearance have been found for different defect size in operation at typical loading levels.Документ Structural Engineering of the Growth of Crystallites with a Predominant Orientation in Bilayer Multi-Period Vacuum arc Nitride Coatings(Sumy State University, 2018) Sobol, O. V.; Mygushchenko, R. P.; Postelnyk, A. A.; Onoprienko, E. V.; Syrenko, T. O.; Men'shikov, A. G.; Zvyagolskiy, A. V.The effect of the MeN (Me-Cr, Mo, Zr) layer composition in multiperiod vacuum-arc (TiAlSi) N / MeN coatings with a nanoscale layer thickness on the predominant orientation of crystallite growth in layer s and hardness was studied. It was found that phases with a cubic crystal lattice (structural type NaCl) in the layers of all types (TiAlSi)N/MeN coatings are formed, although for the MoN phase under equilibrium conditions a hexagonal crystal lattice is preferred. The interrelation between the structure of MeN and (TiAlSi)N layers is revealed, as well as the effect of the structural state on the coating hardness. Defining influence of the MeN layer on the formation of three structural states types was found: with a preferential crystallite growth with the texture axis [111]; with the texture axis [100]; the formation of a non-textured state. The highest hardness of 47.8 GPa was achieved in the (TiAlSi)N/ZrN multilayer coating with the texture axis [111].Документ Structure and Optical Properties CdS and CdTe Films on Flexible Substrate Obtained by DC Magnetron Sputtering for Solar Cells(Сумський державний університет, 2017) Kopach, G. I.; Mygushchenko, R. P.; Khrypunov, G. S.; Dobrozhan, A. I.; Harchenko, M. M.The paper describes investigate of crystal structure and optical characteristics of the CdS transparent window layers and the CdTe base layers, obtained by direct current magnetron sputtering on glass or polyimide substrate, and output parameters the flexible thin film solar cells based on them. The band gap in obtained hexagonal CdS films is Eg = 2.38-2.41 eV and optical transparency of CdS films is 80-90%. Conducting chloride treatment of CdTe layers, obtained at Tп < 300 °C, promotes wurtzite-sphalerite phase transition. Cooling ITO/CdS layers to room temperature before CdTe deposition, removal of the air and subsequent heating in vacuum to the required temperature of the substrate leads to an increase of the energy conversion efficiency and open circuit voltage of the polyimide/ITO/CdS/CdTe/Cu/Ag flexible solar cell.Документ Structure and Optical Properties CdS and CdTe Films on Flexible Substrate Obtained by DC Magnetron Sputtering for Solar Sells(Прикарпатський національний університет ім. Василя Стефаника, 2017) Kopach, G. I.; Mygushchenko, R. P.; Khrypunov, G. S.; Dobrozhan, A. I.; Harchenko, M. M.Документ Structure and Optical Properties of CdS Nanoscale Thin Films Obtained by Direct Current Magnetron Sputtering(Institute of Electrical and Electronics Engineers, 2017) Kopach, G. I.; Mygushchenko, R. P.; Khrypunov, G. S.; Dobrozhan, A. I.; Harchenko, M. M.The influence of physical and technological condensation mode by direct current magnetron sputtering with preheating of the target on the crystal structure and optical properties of grown CdS nanoscale thin films was investigated. CdS layers on glass substrates with hexagonal structure 80-100 nm thick under conditions plasma discharge current density is 1.1 mA/cm² and the deposition rate is 18-20 nm/min were obtained. The band gap CdS in nanoscale thin films is Eg=2,4-2,43 eV. After annealing in vacuum optical transparency of CdS films is 90%, which allows to use such nanoscale thin films as a transparent window layer in solar cells based on heterostructure of CdS/CdTe.Документ Structure and optical properties of CdS polycrystalline layers for solar cells based on CdS/CdTe(Науково-технологічний комплекс "Інститут монокристалів", 2019) Khrypunov, G. S.; Kopach, G. I.; Dobrozhan, A. I.; Mygushchenko, R. P.; Kropachek, О. Y.; Lyubov, V. M.Thin CdS films about 200-500 nm thick with stable hexagonal modification with 85-80 % transparency value respectively in the visible and infrared spectrum regions were investigated. The use of the FTO sublayer to obtain heterosystem glass/FTO/CdS by magnetron sputtering does not affect the phase composition of the cadmium sulfide layer and the width of the band gap (Eg = 2.42-2.44 eV). Cadmium sulfide thin films, obtained by direct current magnetron sputtering, can be used as a layer of a wide window layer in thin-film solar cells based on the CdS/CdTe heterosystem.