Видання зареєстровані авторами шляхом самоархівування
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Item Computer Simulation of Composite Materials Behavior under Pressing(MDPI, 2022) Берладір, Христина Володимирівна; Berladir, Khrystyna Volodymyrivna; Жигилій, Дмитро Олексійович; Zhyhylii, Dmytro Oleksiiovych; Brejcha, J.; Позовний, Олександр Олександрович; Pozovnyi, Oleksandr Oleksandrovych; Krmela, J.; Krmelová, V.; Артюхов, Артем Євгенович; Artiukhov, Artem YevhenovychComposite materials have a wide range of functional properties, which is ensured by using various technological methods of obtaining both the matrix or fillers and the composition as a whole. A special place belongs to the composition formation technology, which ensures the necessary structure and properties of the composite. In this work, a computer simulation was carried out to identify the main dependencies of the behavior of composite materials in the process of the main technological operations of their production: pressing and subsequent sintering. A polymer matrix randomly reinforced with two types of fillers: spherical and short cylindrical inclusions, was used to construct the finite element models of the structure of composites. The ANSYS Workbench package was used as a calculation simulation platform. The true stress–strain curves for tension, Poisson’s ratios, and ultimate stresses for composite materials were obtained using the finite element method based on the micromechanical approach at the first stage. These values were calculated based on the stretching diagrams of the matrix and fillers and the condition of the ideality of their joint operation. At the second stage, the processes of mechanical pressing of composite materials were modelled based on their elastic–plastic characteristics from the first stage. The result is an assessment of the accumulation of residual strains at the stage before sintering. The degree of increase in total strain capability of composite materials after sintering was shown.Item Erosion Modelling of Structural Materials in the Working Space of Multistage Convective Dryers(J. E. Purkyne University in Ústí nad Labem, 2022) Krmela, J.; Берладір, Христина Володимирівна; Берладир, Кристина Владимировна; Berladir, Khrystyna Volodymyrivna; Позовний, Олександр Олександрович; Позовный, Александр Александрович; Pozovnyi, Oleksandr Oleksandrovych; Артюхова, Надія Олександрівна; Артюхова, Надежда Александровна; Artiukhova, Nadiia OleksandrivnaThe application of different structural materials to manufacture basic parts of drying units of various types was analyzed. It has been established that surface erosion of materials resulting from solid par-ticles' impact is a serious problem for many industrial equipment types using multiphase flow. It is shown that the value of the erosion rate depends on the local particle impact velocity and the impact angle and can be calculated using the software Ansys Fluent 18. The basic principles and criteria for selecting materials for the manufacture of chemical equipment were substantiated. The behavior of steel and polymer material for shelf contact of the convective dryer in the conditions of erosion wear was modeled, the comparative characteristic was made, further research was planned.Item Using Regression Analysis for Automated Material Selection in Smart Manufacturing(MDPI, 2022) Павленко, Іван Володимирович; Павленко, Иван Владимирович; Pavlenko, Ivan Volodymyrovych; Pitel, J.; Іванов, Віталій Олександрович; Иванов, Виталий Александрович; Ivanov, Vitalii Oleksandrovych; Берладір, Христина Володимирівна; Берладир, Кристина Владимировна; Berladir, Khrystyna Volodymyrivna; Mizakova, J.; Колос, Віталій Олександрович; Колос, Виталий Александрович; Kolos, Vitalii Oleksandrovych; Trojanowska, J.In intelligent manufacturing, the phase content and physical and mechanical properties of construction materials can vary due to different suppliers of blanks manufacturers. Therefore, evaluating the composition and properties for implementing a decision-making approach in material selection using up-to-date software is a topical problem in smart manufacturing. Therefore, the article aims to develop a comprehensive automated material selection approach. The proposed method is based on the comprehensive use of normalization and probability approaches and the linear regression procedure formulated in a matrix form. As a result of the study, analytical dependencies for automated material selection were developed. Based on the hypotheses about the impact of the phase composition on physical and mechanical properties, the proposed approach was proven qualitatively and quantitively for carbon steels from AISI 1010 to AISI 1060. The achieved results allowed evaluating the phase composition and physical properties for an arbitrary material from a particular group by its mechanical properties. Overall, an automated material selection approach based on decision-making criteria is helpful for mechanical engineering, smart manufacturing, and industrial engineering purposes.Item Modeling of Polymer Composite Materials Chaotically Reinforced with Spherical and Cylindrical Inclusions(MDPI, 2022) Берладір, Христина Володимирівна; Берладир, Кристина Владимировна; Berladir, Khrystyna Volodymyrivna; Жигилій, Дмитро Олексійович; Жигилий, Дмитрий Алексеевич; Zhyhylii, Dmytro Oleksiiovych; Гапонова, Оксана Петрівна; Гапонова, Оксана Петровна; Haponova, Oksana Petrivna; Krmela, J.; Krmelova, V.; Артюхов, Артем Євгенович; Артюхов, Артем Евгеньевич; Artiukhov, Artem YevhenovychThe technical and economic efficiency of new PCMs depends on the ability to predict their performance. The problem of predicting the properties of PCMs can be solved by computer simulation by the finite element method. In this work, an experimental determination of the physical and mechanical properties of PTFE PCMs depending on the concentration of fibrous and dispersed filler was carried out. A finite element model in ANSYS APDL was built to simulate the strength and load-bearing capacity of the material with the analysis of damage accumulation. Verification of the developed computer model to predict the mechanical properties of composite materials was performed by comparing the results obtained during field and model experiments. It was found that the finite element model predicts the strength of chaotically reinforced spherical inclusions of composite materials. This is due to the smoothness of the filler surfaces and the lack of filler dissection in the model. Instead, the prediction of the strength of a finite element model of chaotically reinforced cylindrical inclusions of composite materials requires additional analysis. The matrix and the fibrous filler obviously have stress concentrators and are both subject to the difficulties of creating a reliable structural model.Item Modeling and Optimization of Properties of the Environmentally Clean Molds Based on Oligofurfuryloxysiloxanes for the Production the Metal Castings(MDPI, 2022) Ponomarenko, O.; Yevtushenko, N.; Берладір, Христина Володимирівна; Берладир, Кристина Владимировна; Berladir, Khrystyna Volodymyrivna; Zapolovskyi, M.; Krmela, J.; Krmelovа, V.; Артюхов, Артем Євгенович; Артюхов, Артем Евгеньевич; Artiukhov, Artem YevhenovychThis article is devoted to modeling, researching and optimizing the main properties of an environmentally clean polymer composition based on oligofurfuryloxysiloxanes (OFOS), which can be used to produce casting molds and cores in the production of castings from ferrous and nonferrous metals. Polymer compositions were examined for strength, survivability, gas permeability, moisture, crumbliness, fire resistance, knockout, and stickability. It has been established that the increase in the strength of the polymer composition over time obeys an exponential law. Mathematical equations were derived for all the exponential curves. The indications of compressive strength of the polymer composition with OFOS with all the acid catalysts used were, on average, as follows: after 1 h—1.3–1.54 MPa; after 3 h—2.5–2.9 MPa; after 24 h—4.9–6.1 MPa, which meets the requirements for casting molds before pouring with metal. The use of polymer compositions with OFOS ensures environmental safety of the technological process, due to the lack of emission of toxic substances, both in the “cold” stage of the process and during casting with molten metal, cooling, knocking out, and disposal of polymer compositions. This makes it possible to save energy resources, and thereby reduce the total cost of the entire technological process and castings.Item Impact of Nitrocarburizing on Hardening of Reciprocating Compressor’s Valves(MDPI, 2022) Берладір, Христина Володимирівна; Берладир, Кристина Владимировна; Berladir, Khrystyna Volodymyrivna; Hatala, M.; Говорун, Тетяна Павлівна; Говорун, Татьяна Павловна; Hovorun, Tetiana Pavlivna; Павленко, Іван Володимирович; Павленко, Иван Владимирович; Pavlenko, Ivan Volodymyrovych; Іванов, Віталій Олександрович; Иванов, Виталий Александрович; Ivanov, Vitalii Oleksandrovych; Botko, F.; Гусак, Олександр Григорович; Гусак, Александр Григорьевич; Husak, Oleksandr HryhorovychOne of the urgent problems in reciprocating machinery is ensuring the functional properties of direct-flow valves. Coatings of these parts should increase energy efficiency, reduce compressed gas temperature, and increase compressor performance. In this article, the effect of nitrocarburizing in pastes on increasing the performance and resource of such valves was studied. The primary research methods were metallographic and electron-metallographic research of the surface layer structure of steel 60Si2Cr. Comparison with similar characteristics obtained for stainless steel 09Cr15Ni8Al was also performed. As a result, it was determined that nitrocarburizing of carbon spring steel 60Si2Cr leads to a greater depth of the diffusion layer than nitrocarburizing of alloyed chromium-nickel steel 09Cr15Ni8Al. Simultaneously, the diffusion layers of both types of steel are almost the same. Simultaneously, the increase in the endurance limit of 60Si2Cr steel during nitrocarburizing is about 1.3 times compared to untreated material. Finally, the predictive maintenance showed that the evaluated lifetime of nitrocarburized valves increases by 5.7 times compared with untreated valves.Item Influence of Nitrocarburizing on Increasing the Service Life of Elastic Elements of Direct Flow Valves(Jan Evangelista Purkyne University in Usti nad Labem, 2021) Krmela, J.; Говорун, Тетяна Павлівна; Говорун, Татьяна Павловна; Hovorun, Tetiana Pavlivna; Берладір, Христина Володимирівна; Берладир, Кристина Владимировна; Berladir, Khrystyna Volodymyrivna; Артюхов, Артем Євгенович; Артюхов, Артем Евгеньевич; Artiukhov, Artem Yevhenovych; Kasian, S.The effect of the nitrocarburizing process in pastes with heating in a chamber furnace on the structure and strength characteristics of 09Cr15Ni8Al corrosion-resistant steel was investigated. The technology of thermochemical treatment was developed, which included nitrocarburizing in pastes with heating in a chamber furnace at different holding times. The thickness of the diffusion layer and its microhardness were determined after nitrocarburizing. To determine the efficiency and select the modes of thermochemical treatment, tests were carried out for the investigated steel's strength characteristics. The main feature of the structure of the diffusion layers of valve steels, obtained by nitrocarburizing in the nitrogencarbon paste, is the presence of an inhomogeneous layer with clearly distinguished zones.Item Increasing the Structural Strength of Corrosion-resistant Steel for Elastic Components of Diaphragm Compressor(Jan Evangelista Purkyne University in Usti nad Labem, 2021) Krmela, J.; Говорун, Тетяна Павлівна; Говорун, Татьяна Павловна; Hovorun, Tetiana Pavlivna; Берладір, Христина Володимирівна; Берладир, Кристина Владимировна; Berladir, Khrystyna Volodymyrivna; Артюхов, Артем Євгенович; Артюхов, Артем Евгеньевич; Artiukhov, Artem YevhenovychThe design features of diaphragm compressors are discussed in this article. For preventing the formation of local stresses in certain areas of the diaphragm, it is recommended to use thin sheet stainless steel of the transition class. A comparative analysis is made of two batches of steel tape, differing in the value of the saturation magnetic induction, which is identical to the content of the martensite phase in the structure of the material before the final cycle of cold plastic deformation. The results of the study of the influence of the deformation temperature (20 – 300 ºС) on the change in mechanical properties (σb, σ0.2, δ) revealed a different tendency to embrittlement of the material of the tapes for these batches. For increasing the operational reliability of the compressor's diaphragm elements, it is recommended to use a material, the structure of which contains a certain amount of work-hardened retained austenite. This makes it possible to undergo additional martensitic transformation under the action of peak loads in local areas and increases the structural strength of corrosion-resistant steel for the manufacture of a compressor diaphragm.Item Development of alloy resistant in conditions of abrasive wear(National Academy of Sciences of Ukraine; Department of Physical and Technical Problems of Materials Science; Scientific and Technological Corporation “Institute for Single Crystals”, 2021) Говорун, Тетяна Павлівна; Говорун, Татьяна Павловна; Hovorun, Tetiana Pavlivna; Берладір, Христина Володимирівна; Берладир, Кристина Владимировна; Berladir, Khrystyna Volodymyrivna; Білоус, Олена Анатоліївна; Белоус, Елена Анатольевна; Bilous, Olena Anatoliivna; Любич, Олександр Йосипович; Любич, Александр Иосифович; Liubych, Oleksandr Yosypovych; Воробйов, Сергій Ігорович; Воробьев, Сергей Игоревич; Vorobiov, Serhii IhorovychUsing the method of mathematical planning of the experiment, the composition of surfacing metal containing carbon, titanium, and yttrium was developed, and the calculation of the components of flux-cored wire for surfacing products operating under conditions of abrasive wear was carried out. The influence of elemental composition on wear resistance of surfacing metal with different constant contents of elements for the optimal composition was investigated. The optimal composition of the alloy for surfacing was determined.Item The modeling of the composition and properties of functional materials based on polytetrafluoroethylene(Національна академія наук України; Науково-технологічна корпорація "Інститут монокристалів", 2018) Берладір, Христина Володимирівна; Берладир, Кристина Владимировна; Berladir, Khrystyna Volodymyrivna; Говорун, Тетяна Павлівна; Говорун, Татьяна Павловна; Hovorun, Tetiana Pavlivna; Білоус, Олена Анатоліївна; Белоус, Елена Анатольевна; Bilous, Olena Anatoliivna; Баранова, Світлана Володимирівна; Баранова, Светлана Владимировна; Baranova, Svitlana VolodymyrivnaПроектування та створення нових структур трикомпонентних антифрикційних композитних матеріалів засновані на дослідженнях, що моделюють їх поведінку в умовах напруги. У представлених моделях використаний єдиний підхід, який заснований на варіаційних принципах механіки твердого тіла та дозволяє сформулювати крайові задачі у вигляді умови мінімальності функціоналу. Враховується багатофакторність залежності зношування композиту від його пружності, в’язкопластичності та міцності. Макроскопічні характеристики композитного матеріалу безпосередньо пов’язані з його структурою, яка характеризується просторовим розподілом компонентів і їх властивостями.
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