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Постійне посилання на розділhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/35393
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21 результатів
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Документ Mechanical properties of galvanic metaloxide Fe-Co-MoOₓ coating(ТОВ "Твори", 2021) Tur, Yu. I.; Sakhnenko, M. D.; Ved', M. V.; Yermolenko, I. Yu.; Karakurkchi, G. V.Документ Ceramic-inorganic polymer composites for protection against electromagnetic radiation mechanical properties designing(IOP Publishing Ltd, 2023) Lebedev, V. V.; Miroshnichenko, D. V.; Kryvobok, R. V.; Cherkashina, A. M.; Riabchenko, M. O.The possibility of designing mechanical properties of ceramic-inorganic polymer composites for protection against electromagnetic radiation is considered. As a result, the mechanical properties of polymer composite based on polyamide, modified with ceramic inorganic graphite-ferromagnetic fillers (silicon carbide, chromium oxide Cr2O3 and graphite) was received and optimized. The strength characteristics complex of ceramic-inorganic polymer composites with silicon carbide SiC, chromium oxide Cr2O3 and graphite content in diapason 5-15 % wt. were studied. It was established that the optimal strength characteristics can be received using binary modification of polyamide with ceramic-inorganic graphite-ferromagnetic fillers: polyamide 6 – SiC 10% wt. – Cr2O3 10% wt. and polyamide 6 – SiC 10% wt. – graphite 10% wt. Using mathematical modeling, it was established that the polyamide 6 – SiC 10% wt system is the most optimal for three-component complex modification with ceramic inorganic graphite-ferromagnetic fillers – Cr2O3 10% wt. – graphite 10% wt. By design experimental-statistical mathematical models in equal regressions, mathematical optimization of mechanical properties of polymeric ceramic-inorganic composites contains for protection against electromagnetic radiation was carried out. Designed polymer ceramic-inorganic composites for protection against electromagnetic radiation according to their strength characteristics can be used for modern radio absorbing materials production.Документ РVC compositions with high physical and mechanical properties(Vasyl’ Stus Donetsk National University, 2022) Derius, D. V.; Cherkashina, G. M.; Lebedev, V. V.Документ Effect of deviation from stoichiometry on transport and mechanical properties of Bi2Se3 polycrystals(AIP Publishing, 2021) Menshikova, S. I.; Rogacheva, E. I.The dependences of electrical conductivity, the Hall coefficient, the Seebeck coefficient, thermoelectric power factor and microhardness of Bi2Se3 polycrystals on the degree of deviation from stoichiometry 59.9–60.0 at. % Se and temperature (77–300 K) were obtained. The samples exhibited n-type conductivity in the studied ranges of compositions and temperatures. The boundaries of the Bi2Se3 homogeneity region were estimated. A non-monotonic behavior of the concentration dependences of the properties in the studied composition range, associated with a change in the phase composition and defect structure under the deviation from stoichiometry, was observed. The calculation of the power coefficient in the temperature dependence of electron mobility showed that in a stoichiometric Bi2Se3, electrons are predominantly scattered by acoustic phonons, and under the deviation from stoichiometry the contribution of impurity scattering increases. Based on the experimental data, the Fermi energy EF was calculated in the approximation of the relaxation time and within the framework of the single-band model with a quadratic dispersion law. The obtained values of EF showed that both in stoichiometric and non- stoichiometric Bi2Se3, the conduction is mainly due to electrons in the lower conduction subband.Публікація Percolation transition and physical properties of Bi1-xSbx solid solutions at low Bi concentration(Elsevier Ltd, 2020) Rogacheva, E. I.; Doroshenko, A. N.; Khramova, T. I.; Nashchekina, O. N.; Fedorov, A. G.; Mateychenko, P. V.The dependences of microhardness H, electrical conductivity σ, charge carrier mobility μH, the Seebeck coefficient S, and thermoelectric power factor P = S2σ on the composition of Bi1-xSbx solid solutions in the vicinity of pure Sb (x = 1.0–0.975) were obtained. In the range of x = 0.9925–0.9875, an anomalous decrease in H and S and increase in σ and μH with increasing Bi concentration were observed. For all the alloys, the dependences of H on the load on an indenter G were plotted. It was found that the H(G) dependences for samples with x smaller than ~ 0.99 and for samples with x exceeding 0.99, exhibit different behavior. The results obtained are interpreted on the basis of our assumption about the existence of a percolation-type phase transition from impurity discontinuum to impurity continuum that occurs in any solid solution.Документ Effect of Bi on Mechanical and Transport Properties of Antimony(Прикарпатський національний університет імені Василя Стефаника, 2019) Rogacheva, E. I.; Doroshenko, A. N.; Khramova, T. I.; Men'shov, Yu. V.Документ Influence of pressure of working atmosphere on the formation of phase-structural state and physical and mechanical properties of vacuum-arc multilayer coatings ZrN/CrN(2016) Sobol, O. V.; Andreev, A. A.; Gorban, V. F.; Stolbovoy, V. A.; Meylekhov, A. A.; Postelnyk, A. A.; Dolomanov, A. V.For multilayer coating system ZrN/CrN determined the effect of the pressure of the working atmosphere of nitrogen (Pɴ), DC (˗Us) and pulse (-Ui) negative bias potential during the deposition and the thickness of the layers in the period on the phase composition, texture, substructural characteristics and physical-mechanical properties. It is found that for Рɴ = (2.2...12)·10-4 Torr in the layers of chromium nitride formed on a lower nitrogen phase with the β-Cr2N simple hexagonal crystal lattice, and in the zirconium nitride layers are formed of a stoichiometric ZrN phase with a cubic lattice. Such a multilayer coating (layer thickness about 50 nm) at the maximum in this range Pɴ = 1.2·10-3 Torr is most solid (39 GPa) with a modulus of elasticity of 268 GPa and the ratio H/E = 0.145. At higher Pɴ, when the layers are formed phase stoichiometric composition with homogeneous crystal lattices (ZrN and СrN) hardness of the composition is not more than 33 GPa. The mechanisms of the effects observed are based on the higher barrier properties of the interphase boundary layers with different types of crystal lattices was discussed.Документ Structure and mechanical properties of nitride multilayer systems on the basis of high entropy alloys and transition metals of group VI(2016) Nyemchenko, U. S.; Beresnev, V. M.; Sobol, O. V.; Lytovchenko, S. V.; Stolbovoy, V. A.; Novikov, V. Ju.; Meylekhov, A. A.; Postelnyk, A. A.; Kovaleva, M. G.The influence of technological parameters of obtaining on the possibilities of structural engineering and mechanical properties of multilayer compositions of the layers of nitrides of high entropy alloy Ti-Zr-Nb-Ta-Hf and of transition metal (Group IV) nitrides has been analysed. It is shown that with the bias potential Ub lesser than -150 V was applied to the substrate during deposition, a two-phase state with the preferred orientation of the crystallites can be reached in multilayer coatings with the thickness of the layers of 50 nm. This leads to high hardness (up to 44 GPa) and to high adhesion strength (critical load up to 125 N) as well as to low wear (with a counterbody Al ₂O₃, and with steel Ac100Cr6). High-temperature annealing (700 ⁰C) of such coatings leads to enhanced texture as a result of atomic ordering, which is accompanied by increasing of hardness up to 59 GPa. The supply of bias potential exceeding 150 V, followed by a substantial mixing at the interphase boundary results in disorientation and improves dispersion of the crystallites, reduces hardness and wear resistance. High temperature annealing of such structures leads to reduction of their mechanical properties.Документ Применение отходов химической промышленности в производстве специальных вяжущих материалов(Ліра, 2016) Шабанова, Галина Николаевна; Корогодская, Алла Николаевна; Гапонова, Елена Александровна; Нагорный, Андрей Олегович; Ворожбиян, Роман Михайлович; Христич, Елена ВалерьевнаПредставлены результаты установления возможности использования отходов химической отрасли промышленности, которые могут частично или полностью заменить исходные компоненты при производстве специальных глиноземистых цементов. Обоснована необходимость рекуперации таких отходов с точки зрения охраны окружающей среды.Документ Development of glass-ceramic high-strength material for personal armor protection elements(Національний університет "Львівська політехніка", 2017) Savvova, Oksana; Bragina, L. L.; Voronov, Gennadii; Sobol, Yuliya; Babich, Olena; Shadrina, Galina; Kuriakin, MykolaThe perspective of glass-ceramic high-strength materials used for personal armor elements has been established. The methodological approach has been developed and the choice of initial lithium aluminosilicate system for obtaining high-strength lightweight glassceramic materials has been substantiated. The glass formation area in the chosen system was studied, and model glasses were synthesized. Features of crystal structure formation during heat treatment of the developed model glasses were investigated. As a result, high-strength glass-ceramic materials have been developed. It has been determined that they possess high performance characteristics and can be used in manufacturing of modern composite armor.
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