Dissertations / Theses on the topic 'Міцність структури'
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Дейнека, Андрій Віталійович, Андрей Витальевич Дейнека, and Andrii Vitaliiovych Deineka. "Конструкційна міцність багатошарових елементів машин з дефектами структури." Thesis, Вид-во СумДУ, 2015. http://essuir.sumdu.edu.ua/handle/123456789/40752.
Full textВ диссертационной работе решен ряд важных научно-технических задач, которые включают в себя обоснование моделей и методик расчета напряженно-деформированного и термоупругого состояния многослойных оболочек вращения с межслойными дефектами структуры. Разработанные алгоритмы, программы, методики исследований и полученные на их основе теоретико-экспериментальные результаты показали наличие новых особенностей деформированного состояния рассматриваемых конструкций. Построено замкнутую систему дифференциальных уравнений и соответствующие краевые условия несвязанной стационарной задачи термоупругого деформирования многослойной композитной оболочки, позволяющие учесть деформации поперечного сдвига и трансверсального обжатия, обеспечить условия механического и теплового сопряжения слоев и условия термомеханической нагрузки на лицевых поверхностях такой оболочки. На основе классической теории упругости анизотропного тела разработан численно-аналитический подход решения термоупругих несвязанных краевых задач для цилиндрических толстостенных оболочек при условии как идеального, так и неидеального контакта соседних слоев по сопряженным поверхностям. Установлено влияние температурных нагрузок на напряженно-деформированное состояние уплотнения рабочего колеса, изготовленного из композиционных материалов. Решена задача прочности и получена величина граничного внутреннего давления комбинированных газовых баллонов высокого давления. Исследовано напряженно-деформированное состояние стеклопластиковых труб в зоне фланцевых соединений в зависимости от жесткости фланцев.
The thesis presents number of important scientific and technical problems, which include study models and methods of calculating the stress-strain and the thermoelastic state multilayer shells with interlayer structural defects. The algorithms, programs, research methodology, theoretical and experimental results showed the presence of new features deformed state considered structures. We construct a closed system of differential equations and appropriate boundary conditions unrelated stationary problem thermostatic deformation of the multilayer composite shell that allow for deformations of transverse shear and transversal compression, ensure conditions of mechanical and thermal connection layers and thermomechanical loading conditions on the front surface of this shell. Based on the classical theory of elasticity of an anisotropic body developed numerical-analytical approach solving of thermoelastic unrelated boundary problems for thick-walled cylindrical shells provided ideal and non-ideal contact of adjacent layers on surfaces mated. The influence of temperature loads on the stress-strain state seal rotor made from composite materials was found.
Данільцев, В. В. "Міцність конструкцій зі склопластику з міжшаровими дефектами структури матеріалу." Thesis, Сумський державний університет, 2016. http://essuir.sumdu.edu.ua/handle/123456789/46034.
Full textВ диссертационной работе решен ряд важных научно-технических заданий, которые включают в себя обоснования моделей и методик расчета напряженно-деформированного и термоупругого состояния многослойных оболочек вращения с межслойными дефектами структуры. Разработана и апробирована методика определения интегральных термо-упругих характеристик композитов слоистой структуры, предложен алгоритм определения коэффициентов теплового линейного расширения и теплопро-водности многослойного анизотропного материала. Определено термоупругое деформированное состояние многослойных оболочек вращения. Решена задача конструкционной прочности и создана методика определения предельного внутреннего давления многослойных цилиндрических оболочек, изучено напряженное состояние стеклопластиковых труб в зоне фланцевых, бандажных и муфтовых соединений. При помощи модифицированного полиноминального критерия прочности получены значения предельного давления, при котором произойдет разрушение стеклопластиковой трубы в точках контакта ее поверхности с металлическими фланцами.
A number of important scientific and technical tasks has been solved in this dissertation, including the justification of the models and methods of calculation of the stressed and strained state as well as the thermoelastic state of layered rota-tion shells with interlaminar structure defects. The method of the integral thermoelastic characteristics of layered structure composite determination has been developed and tested; the algorithm of the thermal linear extention and thermal conductivity of layered anisotropic material coefficient definition was suggested. The thermoelastic strained state of multilayer rotation shells has been determined. The problem of the structural strength has been solved and the technique of determining the maximum internal pressure of multi-layered cylindrical shells has been invented; the stress state of the GRP pipes in flange, bandage and socket joint areas has been studied.Using the modified polynomial strength criterion, the critical pressure values, at which the rupture occurs at the points of GRP pipes surface contact with metal flanges, have been calculated.
Бєлла, О. О. "Дослідження структури та властивостей композитів на основі політетрафторетилену з різними наповнювачами." Master's thesis, Сумський державний університет, 2020. https://essuir.sumdu.edu.ua/handle/123456789/81369.
Full textСаранчук, А. В. "Дослідження структури, властивостей та характеристик сталі 12Х18Н10Т після хіміко-термічної обробки." Master's thesis, Сумський державний університет, 2020. https://essuir.sumdu.edu.ua/handle/123456789/81723.
Full textThe work is devoted to the study of the microstructure, mechanical properties and characteristics of steel 12Х18Н10Т (AISI 321) after chemical-heat treatment, namely after diffusion simultaneous saturation with silicon and chromium. The feasibility of using this type of coating on steel 12X18H10T (AISI 321) is confirmed by tensile tests. The resistance of steel 12Х18Н10Т to intergranular corrosion was proved experimentally. The confirmed are prospects of this type of coating as wear-resistant.
Щукіна, Людмила Павлівна, Георгій Вікторович Лісачук, Ярослав Олегович Галушка, Олена Юріївна Федоренко, and Лариса Олександрівна Міхеєнко. "Технологічна цінність промислових хімічних добавок при їх використанні у виробництві будівельної кераміки." Thesis, Одеський національний політехнічний університет, 2013. http://repository.kpi.kharkov.ua/handle/KhPI-Press/31485.
Full textThe technological efficiency of complex surface-active additive "MasterCeram" using to improve the properties of ceramic masses and materials in the manufacture of wall ceramics is investigated. The water-reducing effect of the additive and its positive influence on the strength of the coagulation and condensation structure of ceramic masses are established. The optimal amount of additive, which recommended for use in the manufacture of terraced wall ceramic, are established.
Шевченко, Олександр Іванович. "Інтегральні методи визначення фізичних властивостей чавуну, хрому та їх покриттів для контролю структури і міцності виробів." Doctoral thesis, Київ, 2015. https://ela.kpi.ua/handle/123456789/13795.
Full textКараш, Імад Тома Бане, Имад Тома Бане Караш, and Imad Toma Bane Karash. "Конструкционная прочность стеклопластиковых оболочек вращения с межслойными дефектами структуры." Thesis, Изд-во СумГУ, 2012. http://essuir.sumdu.edu.ua/handle/123456789/30017.
Full textРассоха, Олексій Миколайович, Ганна Миколаївна Черкашина, and І. С. Корнева. "Фурано-епоксидні антикорозійні покриття градієнтної структури на поверхні будівельних залізобетонних виробів." Thesis, ТОВ "Нілан-ЛТД", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/48747.
Full textВолков, Олег Олексійович, М. А. Погрібний, and Юрій Анатолійович Сизий. "Дослідження ролі теплових явищ у формуванні структур та властивостей сталей різних марок при зміцненні методом ТФО." Thesis, НТУ "ХПІ", 2010. http://repository.kpi.kharkov.ua/handle/KhPI-Press/9488.
Full textКучеренко, Є. В., and Ю. О. Будаш. "Властивості високоеластичних матеріалів, одержаних з волокнистих відходів." Thesis, Київський національний університет технологій та дизайну, 2017. https://er.knutd.edu.ua/handle/123456789/8638.
Full textВуєць, Олександр Євгенович, and С. В. Григор'єва. "Механічні властивості та структурні особливості сталі в залежності від швидкості нагрівання при відпуску." Thesis, Національний технічний університет "Харківський політехнічний інститут", 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/41179.
Full textНевмержицький, І. В. "Автоматизована система керування автоклавом для сушки газобетонних блоків." Thesis, Київський національний університет технологій та дизайну, 2019. https://er.knutd.edu.ua/handle/123456789/13764.
Full textСупрун, О. В., Оксана Петрівна Гапонова, Оксана Петровна Гапонова, and Oksana Petrivna Haponova. "Вивчення впливу термічної обробки на структуру та властивості корозійностійкої сталі аустенітно-мартенситного класу типу ВНЛ-6." Thesis, Сумський державний університет, 2015. http://essuir.sumdu.edu.ua/handle/123456789/39526.
Full textЦиганенко, Наталія Іванівна. "Вплив легування на структуру та властивості евтектичних та доевтектичних титан-боридних і титан-силіцидо-боридних сплавів." Doctoral thesis, Київ, 2015. https://ela.kpi.ua/handle/123456789/13820.
Full textБерладір, Христина Володимирівна. "Антифрикційні матеріали на основі механоактивованих політетрафторетилену та наповнювачів." Thesis, КПІ ім. Ігоря Сікорського, 2017. https://ela.kpi.ua/handle/123456789/19665.
Full textThe thesis is devoted to creation of composites of tribotechnical appointment with the increased operational properties based on mechanically activated polytetrafluoroethylene and fillers of various chemical nature. An approach of preparation of a matrix and fillers of various chemical nature for obtaining PTFE-composites by the reasonable choice of a ratio of ingredients and technology of their modifying is offered. The optimum modes of process of mechanical activation of PTFE-matrix, fibrous and disperse fillers are set. Influence of technological parameters of process of mechanical activation on structure, physical and mechanical and tribotechnical properties of the PTFE-composite is studied. It is shown that under the influence of mechanical activation the ordered spherolitic supramolecular structure of matrix PTFE is formed which is characterized micro- and the nanoscale and leads to an increase in the thermal resistance of a modified polymer on (293–353) K. It is established that mechanical activation does not result in noticeable destruction of polytetrafluoroethylene molecular chain, but there are conformational changes which consist in an increase in concentration of the valent and finite CF2 groups that can lead to enhanced physical, mechanical and service properties of the polymer. It is revealed that the main factors that determine tribotechnical and physical and mechanical properties of PTFE are the time of activation and rotating speed of working organs of a mill. It is mathematically proved the practical experimental mode of mechanical activation at which operational characteristics of matrix PTFE are maximum (n = 9000 min.-1, τ = 5 min.). In comparison with non-activated polymer the level of breaking strength has grown by 2,6 times, relative elongation - by 4,3 times, wear resistances – by 1,86 times. Different technological methods of increasing the adhesive interaction between the ingredients of PTFE-composites are investigated. The prospects of using mechanical activation not only of the matrix but also fillers of various chemical nature for improving of operational characteristics of composites are shown. The determining factor of increase in a complex of operational properties of mechanically activated PTFE-composites is forming spherolitic composite structure under the influence of active particles of disperse layered fillers which playing a role of germs of crystallization and formation on a surface of fibers and coke of the interfacial layer of PTFE which contributes to the emergence of a stable spatial cluster of a filler in volume of a matrix of composition and allows to reach the maximum reinforcing effect, thereby, raising strengthening characteristics of the material and its wear resistance. It is revealed that introduction of a binary filler increases wear resistance of the developed composites by (2,6–4,1) times in comparison with two-component composites. The greatest increase in wear resistance at preservation of high values of physical and mechanical properties of PTFE-composites is watched at synergetic effect of application of mechanical activation of a matrix, fillers, their mixing by two-stage mode and use of a binary filler of various chemical nature. The feature of the developed manufacturing technology of PTFE-composites consists in preliminary separate preparation of a matrix and fillers before their mixing by mechanical activation at various modes of the equipment therefore there is an increase in level of their breaking strength by 1,4 times and wear resistances by (3,7–6,0) times in comparison with industrial analogs that increases durability of work of frictional units of the compressor by (1,8–2,3) times. Piston rings and packing seals of piston-type compressors 4ГМ 2,5 У-3,4/2,8-251 are made of developed PTFE-material that successfully passed industrial tests at LLC «Scientific and innovative enterprise SumyPlastPolymer» and they are not worse than the industry samples. Technological process of PTFE-composite production is developed.
Диссертация посвящена созданию композитов триботехнического назначения с повышенными эксплуатационными свойствами на основе механоактивированных ПТФЭ и наполнителей различной химической природы. Предложен подход подготовки матрицы и наполнителей различной химической природы для получения ПТФЭ-композитов путем обоснованного выбора соотношения ингредиентов и технологии их модифицирования. Установлены оптимальные режимы процесса механической активации матричного ПТФЭ, волокнистых и дисперсных наполнителей. Изучено влияние технологических параметров процесса механической активации на структуру, физико-механические и триботехнические свойства ПТФЭ-композита. Из разработанного ПТФЭ-композита изготовлены поршневые кольца и сальниковые уплотнения поршневых компрессоров 4ГМ 2,5 У–3,4/2,8–251, которые успешно прошли промышленные испытания на ООО «Научно-внедренческое предприятие СумыПластПолимер» и по эксплуатационным характеристикам не уступают промышленным образцам.
Одинцова, Олександра Павлівна. "Безпігментні одношарові склоемалеві покриття для побутової техніки." Thesis, НТУ "ХПІ", 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/33516.
Full textThe dissertation on competion of a scientific degree of the candidate of engineering science on a speciality 05.17.11 "Technology of refractory nonmetallic materials". – National Technical University "Kharkiv Polytechnical Institute", Kharkiv, 2017. The dissertation is devoted to the development of pigments free direct chemically and thermally resistant dark-colored glass-enamel coatings for the protection of household appliances, in particular kitchen gas and electric plates, obtained by the technology POESTA. The bases of obtaining the coatings of this type are synthesized, according to which the glass matrix is developed with the given physicochemical properties, on the basis of which glassmelee frit is obtained by introducing into the optimized composition of the MS complex agglomer activator, simultaneously performing the role of the active coloring complex which combines the specified strength characteristics of pigments free direct glass-enamel coatings with their dark coloring. The boundaries of the values of structural factors, which provide a solid structure of the silica-oxygen glass frame in the system R₂O (Na₂O+K₂O+Li₂O) – RO (CaO+BaO+SrO+MgO) – TiO₂ – ZrO₂ – B₂O₃ – SiO₂ and the specified level of its structurally dependent performance properties due to the established ratios of glass modifiers and modifiers. The composition and ratio of the complex coupler activator have been developed taking into account its influence on the strength characteristics of the glass-enamel-steel system, the corrosion capacity of the glass-fiber alloy and the operational properties of the coatings at the firing temperatures of 800 to 830 °C. Selected the ionic mechanism of color, which was realized by the components of the filling station, and the color coordinates are established in the XYZ, RGB, L*a*b, according to RAL. Industrial and laboratory-industrial tests were carried and practical recommendations for the use of development results are developed.
Одинцова, Олександра Павлівна. "Безпігментні одношарові склоемалеві покриття для побутової техніки." Thesis, НТУ "ХПІ", 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/33515.
Full textThe dissertation on competion of a scientific degree of the candidate of engineering science on a speciality 05.17.11 "Technology of refractory nonmetallic materials". – National Technical University "Kharkiv Polytechnical Institute", Kharkiv, 2017. The dissertation is devoted to the development of pigments free direct chemically and thermally resistant dark-colored glass-enamel coatings for the protection of household appliances, in particular kitchen gas and electric plates, obtained by the technology POESTA. The bases of obtaining the coatings of this type are synthesized, according to which the glass matrix is developed with the given physicochemical properties, on the basis of which glassmelee frit is obtained by introducing into the optimized composition of the MS complex agglomer activator, simultaneously performing the role of the active coloring complex which combines the specified strength characteristics of pigments free direct glass-enamel coatings with their dark coloring. The boundaries of the values of structural factors, which provide a solid structure of the silica-oxygen glass frame in the system R₂O (Na₂O+K₂O+Li₂O) – RO (CaO+BaO+SrO+MgO) – TiO₂ – ZrO₂ – B₂O₃ – SiO₂ and the specified level of its structurally dependent performance properties due to the established ratios of glass modifiers and modifiers. The composition and ratio of the complex coupler activator have been developed taking into account its influence on the strength characteristics of the glass-enamel-steel system, the corrosion capacity of the glass-fiber alloy and the operational properties of the coatings at the firing temperatures of 800 to 830 °C. Selected the ionic mechanism of color, which was realized by the components of the filling station, and the color coordinates are established in the XYZ, RGB, L*a*b, according to RAL. Industrial and laboratory-industrial tests were carried and practical recommendations for the use of development results are developed.
Мартиненко, Володимир Геннадійович. "Розробка методів розрахунку елементів конструкцій із в'язкопружних композиційних матеріалів." Thesis, НТУ "ХПІ", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/37543.
Full textThesis for granting the Degree of Candidate of Technical sciences in speciality 05.02.09 – Dynamics and Strength of Machines. – National Technical University "Kharkiv Politechnical Institute", 2018. The thesis is dedicated to a creation of new methods for describing and modeling the anisotropic viscoelasticity of composite structural elements. Basing on an analysis of actual methods it is established that at the moment there is no a complex approach for determining anisotropic viscoelastic parameters of polymer reinforced composite materials and modeling their mechanical behavior. With a purpose of finding the quantitative and qualitative properties of a viscoelastic composite, a numerical method for homogenizing orthotropic viscoelastic kernels of orthogonally reinforced composite material, that are dependent on a fiber volume fraction, time and temperature, was developed. The time dependencies of these kernels were approximated by Prony series, whereas the temperature ones were approximated by Williams-Landel-Ferry shift function. This approach allowed to indicate that the viscoelasticity of fiber reinforced polymeric composite materials is of orthotropic nature for an orthogonal reinforcement scheme, that the relaxation curves of viscoelastic parameters are not similar to each other, which contradicts the classical engineering viscoelastic models, and that the temperature dependency of these properties coincide with the ones of the composite polymeric matrix. The planned and realized experiment on finding the parameters of anisotropic viscoelasticity of a fiber-glass with a woven reinforcement scheme has confirmed the results of numerical calculations, which demonstrated the need to take into account viscoelastic properties with a general degree of anisotropy when modeling the mechanics of structural elements and machines made of fiber reinforced polymeric composite materials. The experiment rig was improved during the research in order to satisfy the requirements for carrying out tests on plane polymeric composite samples. The method of super-imposed meshes proposed in the work provided the possibilities of modeling any degree of anisotropy of viscoelastic properties in commercial finite-element codes without a necessity to create additional material user subroutines using only the standard tools of these codes. The convergence of the method was also proved in the work. This method was applied to modeling a contact behavior of an elastic pipeline section with an orthotropic viscoelastic repair bandage using a three-dimensional viscoelastic finite element model that in comparison with the developed analytical and numerical-analytical models of a plane axisymmetric stress-strain state of such a design showed its adequacy and accuracy. In addition, proposed analytical and numerical-analytical methods allowed to take into account mounting features of repair band-age assembled on unloaded or loaded pipeline with or without tension, that enabled to indicate a relaxation of contact stresses for different repair regimes.
Мартиненко, Володимир Геннадійович. "Розробка методів розрахунку елементів конструкцій із в'язкопружних композиційних матеріалів." Thesis, НТУ "ХПІ", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/37542.
Full textThesis for granting the Degree of Candidate of Technical sciences in speciality 05.02.09 – Dynamics and Strength of Machines. – National Technical University "Kharkiv Politechnical Institute", 2018. The thesis is dedicated to a creation of new methods for describing and modeling the anisotropic viscoelasticity of composite structural elements. Basing on an analysis of actual methods it is established that at the moment there is no a complex approach for determining anisotropic viscoelastic parameters of polymer reinforced composite materials and modeling their mechanical behavior. With a purpose of finding the quantitative and qualitative properties of a viscoelastic composite, a numerical method for homogenizing orthotropic viscoelastic kernels of orthogonally reinforced composite material, that are dependent on a fiber volume fraction, time and temperature, was developed. The time dependencies of these kernels were approximated by Prony series, whereas the temperature ones were approximated by Williams-Landel-Ferry shift function. This approach allowed to indicate that the viscoelasticity of fiber reinforced polymeric composite materials is of orthotropic nature for an orthogonal reinforcement scheme, that the relaxation curves of viscoelastic parameters are not similar to each other, which contradicts the classical engineering viscoelastic models, and that the temperature dependency of these properties coincide with the ones of the composite polymeric matrix. The planned and realized experiment on finding the parameters of anisotropic viscoelasticity of a fiber-glass with a woven reinforcement scheme has confirmed the results of numerical calculations, which demonstrated the need to take into account viscoelastic properties with a general degree of anisotropy when modeling the mechanics of structural elements and machines made of fiber reinforced polymeric composite materials. The experiment rig was improved during the research in order to satisfy the requirements for carrying out tests on plane polymeric composite samples. The method of super-imposed meshes proposed in the work provided the possibilities of modeling any degree of anisotropy of viscoelastic properties in commercial finite-element codes without a necessity to create additional material user subroutines using only the standard tools of these codes. The convergence of the method was also proved in the work. This method was applied to modeling a contact behavior of an elastic pipeline section with an orthotropic viscoelastic repair bandage using a three-dimensional viscoelastic finite element model that in comparison with the developed analytical and numerical-analytical models of a plane axisymmetric stress-strain state of such a design showed its adequacy and accuracy. In addition, proposed analytical and numerical-analytical methods allowed to take into account mounting features of repair band-age assembled on unloaded or loaded pipeline with or without tension, that enabled to indicate a relaxation of contact stresses for different repair regimes.