Персона:
Джумаев, Павел Сергеевич

Научные группы

Научная группа

Лаборатория ионно-плазменной и ионно-пучковой обработки материалов (Кафедра №9)

Организационные подразделения

Организационная единица

Цель ИЯФиТ и стратегия развития - создание и развитие научно-образовательного центра мирового уровня в области ядерной физики и технологий, радиационного материаловедения, физики элементарных частиц, астрофизики и космофизики.

Статус

Руководитель научной группы "Лаборатория ионно-плазменной и ионно-пучковой обработки материалов"

Фамилия

Джумаев

Имя

Павел Сергеевич

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Теперь показываю 1 - 10 из 43

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Laser Milling Ceramics Dioxide Zirconium and Disilicate of Lithium
(2019) Panov, D. V.; Petrovskiy, V. N.; Ushakov, D. V.; Osintsev, A. V.; Dzhumaev, P. S.; Polskiy, V. I.; Петровский, Анатолий Николаевич; Осинцев, Андрей Вениаминович; Джумаев, Павел Сергеевич; Польский, Валерий Игоревич
© Published under licence by IOP Publishing Ltd.The paper considers the possibility of using laser milling technology for precision processing of ceramic samples from pre-sintered and sintered ceramics zirconia and lithium disilicate. To find the best radiation source were compared different lasers. To find highest removal rate with acceptable accuracy was studied influence laser and scanning system parameters on ceramics. Accuracy problem of laser milling was considered. Examples of surfaces of prostheses were made.
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Microstructure and mechanical properties of stainless steel 316L obtained by Direct Metal Laser Deposition
(2019) Bykovskiy, D. P.; Ishkinyaev, E. D.; Petrovskiy, V. N.; Osintsev, A. V.; Dzhumaev, P. S.; Polskiy, V. I.; Sergeev, K. L.; Shchekin, A. S.; Быковский, Дмитрий Петрович; Ишкиняев, Эмиль Дамирович; Петровский, Анатолий Николаевич; Осинцев, Андрей Вениаминович; Джумаев, Павел Сергеевич; Польский, Валерий Игоревич; Щекин, Александр Сергеевич
© Published under licence by IOP Publishing Ltd.The microstructure of 316L stainless steel obtained by layer-by-layer direct metal laser deposition is reviewed. Mechanical tests of the samples were performed in accordance with GOST 1497-84. Studies show that changes in power of laser radiation to grow parts lead to changes in their mechanical properties. The research shows dependencies between the strength characteristics of materials and the power of laser radiation. Causes of the forementioned changes are studied through the analysis of the microstructure. Nanosized inclusions of spherical shape were found in the process of studying the microstructure of materials. A study in the nature of the formation of these inclusions and their effect on the properties of the obtained material was performed.
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Ferromagnet/Superconductor Hybrid Magnonic Metamaterials
(2019) Golovchanskiy, Igor A.; Abramov, Nikolay N.; Stolyarov, Vasily S.; Golubov, Alexander A.; Dzhumaev, Pavel S.; Emelyanova, Olga V.; Джумаев, Павел Сергеевич; Емельянова, Ольга Владимировна
In this work, a class of metamaterials is proposed on the basis of ferromagnet/superconductor hybridization for applications in magnonics. These metamaterials comprise of a ferromagnetic magnon medium that is coupled inductively to a superconducting periodic microstructure. Spectroscopy of magnetization dynamics in such hybrid evidences formation of areas in the medium with alternating dispersions for spin wave propagation, which is the basic requirement for the development of metamaterials known as magnonic crystals. The spectrum allows for derivation of the impact of the superconducting structure on the dispersion: it takes place due to a diamagnetic response of superconductors on the external and stray magnetic fields. In addition, the spectrum displays a dependence on the superconducting critical state of the structure: the Meissner and the mixed states of a type II superconductor are distinguished. This dependence hints toward nonlinear response of hybrid metamaterials on the magnetic field. Investigation of the spin wave dispersion in hybrid metamaterials shows formation of allowed and forbidden bands for spin wave propagation. The band structures are governed by the geometry of spin wave propagation: in the backward volume geometry the band structure is conventional, while in the surface geometry the band structure is nonreciprocal and is formed by indirect band gaps.
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Micro-catalytic gas sensor operating modes for extended life service, increasing sensitivity to target gases and power consumption reduction
(2020) Ducso, C.; Samotaev, N.; Oblov, K.; Dzhumaev, P.; Filipchuk, D.; Самотаев, Николай Николаевич; Облов, Константин Юрьевич; Джумаев, Павел Сергеевич
© 2020 Institute of Physics Publishing. All rights reserved.Catalytic gas sensors are among of the most old and widespread gas sensors for combustible gas concentration measurements. However, power consumption these sensors provide is relativity high for modern electronic applications. In this paper research results of combination a silicon MEMS fabrication with operating modes for extended life service, increasing sensitivity to target gases and power consumption reduction are presented. The described solutions allow achieving long-term stability of the sensor in difficult operating conditions - the main requirement for industrial applications, where the continuity of the process is of high value expressed in tangible assets and human lives.
Только метаданные
Vacuum brazing of AA 6082 aluminum alloy and AISI 304 stainless steel with Ti coating using rapidly quenched Al-Ge-Si system filler alloy
(2024) Ivannikov, А. A.; Abramov, A. V.; Dzhumaev, P. S.; Terekhova, S. M.; Sevryukov, O. N.; Иванников, Александр Александрович; Абрамов, Антон Владиславович; Джумаев, Павел Сергеевич; Терехова, Софья Михайловна; Севрюков, Олег Николаевич
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Thermal Conductivity Gas Sensors for High-Temperature Applications
(2024) Samotaev, N.; Podlepetsky, B.; Mashinin, M.; Ivanov, I.; Obraztsov, I.; Oblov, K.; Dzhumaev, P.; Самотаев, Николай Николаевич; Подлепецкий, Борис Иванович; Машинин, Михаил Олегович; Иванов, Игорь Александрович; Образцов, Иван Сергеевич; Облов, Константин Юрьевич; Джумаев, Павел Сергеевич
This paper describes a fast and flexible microfabrication method for thermal conductivity gas sensors useful in high-temperature applications. The key parts of the sensor, the microheater and the package, were fabricated from glass-coated platinum wire and the combination of laser micromilling (ablation) of already-sintered monolithic ceramic materials and thick-film screen-printing technologies. The final thermal conductivity gas sensor was fabricated in the form of a complete MEMS device in a metal ceramic package, which could be used as a compact miniaturized surface-mounted device for soldering to standard PCB. Functional test results of the manufactured sensor are presented, demonstrating their full suitability for gas sensing applications and indicating that the obtained parameters are at a level comparable to those of standard industrially produced sensors. The results of the design and optimization principles of applied methods are discussed with regard to possible wider applications in thermal gas sensor prototyping in the future. The advantage of the developed sensors is their ability to operate in air environments under high temperatures of 900 ‚шC and above. The sensor element material and package metallization were insensitive to oxidation compared with classical sensor-solution-based metalў??glass packages and silicone MEMS membranes, which exhibit mechanical stress at temperatures above 700 ‚шC.
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Simulated thermal tests of a molybdenum/graphite X-ray target manufactured with a novel Ti-Zr-Nb-Be powder filler metal: an investigation of the brazed joint evolution under operating conditions
(2021) Sliva, A.; Svetogorov, R.; Fedotov, I.; Suchkov, A.; Dzhumaev, P.; Kozlov, I.; Sevryukov, O.; Федотов, Иван Владимирович; Сучков, Алексей Николаевич; Джумаев, Павел Сергеевич; Козлов, Илья Владимирович; Севрюков, Олег Николаевич
© 2021 The Society of Manufacturing EngineersIn this work, two molybdenum-graphite X-ray targets for computed tomography/angiography devices were manufactured with usage of Ti-40Zr-8.5Nb-1.5Be filler metal and 1400 °C – 20 min brazing mode. To confirm the efficiency of the proposed brazing method, a mechanical test and simulated heating of the anodes were carried out, as well as a study of the evolution of the brazed joint under operating conditions. The brazed joint of the anodes showed stability and maintained integrity after tests. However, it is revealed that the long-term heat treatment of the brazed Mo/graphite joint leads to an increase in the amount of carbides in the seam, and also converts the seam into a refractory state by suppressing the formation of beryllium eutectic, while the cyclic heating mainly affects the recrystallization of the seam phases, leading to phase fragmentation. Shear strength tests after simulated heating show that the failure of the Mo/graphite joint occurs in the graphite element with cracking due to the infiltration of the filler metal into graphite through the open porosity. Infiltrates could provoke the occurrence of stresses during cyclic heating/cooling because of the difference in the CTE of graphite and carbide phases. Nevertheless, the joints remained integrity and showed a minimal strength of 23.4 ± 2.5 MPa (after 20 heating cycles of 350 ↔ 1400 °C) and 26.1 ± 6.4 MPa (after vacuum annealing of 1400 °C – 8 h).
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Josephson current mediated by ballistic topological states in Bi2Te2.3Se0.7 single nanocrystals
(2020) Stolyarov, V. S.; Yakovlev, D. S.; Kozlov, S. N.; Skryabina, O. V.; Emelyanova, O. V.; Dzhumaev, P. S.; Емельянова, Ольга Владимировна; Джумаев, Павел Сергеевич
© 2020, The Author(s).Superconducting proximity devices using low-dimensional semiconducting elements enable a ballistic regime in the proximity transport. The use of topological insulators in such devices is considered promising owing to the peculiar transport properties these materials offer, as well the hope of inducing topological superconductivity and Majorana phenomena via proximity effects. Here we demonstrate the fabrication and superconducting properties of proximity Josephson devices integrating nanocrystals single of Bi2Te2.3Se0.7 with a thickness of a few unit cells. Single junctions display typical characteristics of planar Josephson devices; junctions integrating two nanocrystals behave as nanodimensional superconducting quantum interference devices. A peculiar temperature and magnetic field evolution of the Josephson current along with the observed excess current effect point towards the ballistic proximity regime of topological channels. This suggests the proposed devices are promising for testing topological superconducting phenomena in two-dimensions.
Только метаданные
Investigation of Stainless Steel Obtained by Additive Technology as Applied to the Operating Conditions of Liquid Metal Heat-Exchange Systems
(2020) Ladyko, M. A.; Eremin, A. G.; Logachev, I. A.; Sentyurina, Z. A.; Lyublinski, I. E.; Dzhumaev, P. S.; Джумаев, Павел Сергеевич
© 2020, Pleiades Publishing, Ltd.Abstract: The properties of stainless steel grade GP1 obtained by additive technology (AT) by the method of selective laser melting (SLM) in relation to the operating conditions of liquid metal heat-exchange systems of power plants (vacuum density, corrosion effect of eutectic sodium and potassium alloy Na–K at temperature 700 ± 5°С) are investigated. The microstructure of GP1 steel has a fine structure with a characteristic size of structural components from 2 to 3 μm. The results of local chemical analysis of the identified structural components of the material showed a high degree of material homogeneity. The material is sealed, the flow of helium into the sample made by AT was no more than 4 × 10–10 (Pa m3)/s. Under the conditions of the tests performed, the corrosive effect of Na–K on the material is observed in the surface layers with a thickness of no more than 2 μm. The corrosion rate of the test material under test conditions was less than 0.01 mm/year, which, according to the existing classification of corrosion resistance, makes it possible to assign the test material under test conditions to the resistance group of extremely resistant. The results give grounds to continue research on a larger time base and in conditions close to the operating conditions of the heat-exchange systems of power plants (non-isothermal dynamic conditions), as well as to conduct research on other steels obtained by AT, for example, chromium-nickel corrosion-resistant steel of austenitic class with a high level of corrosion resistance in the environment of the liquid metal coolant Na–K of eutectic composition.
Только метаданные
Nonthermal Mechanism of Defect Formation in the CdHgTe Semiconductor on Exposure to Soft X-rays
(2019) Sredin, V. G.; Ramakoti, R. S.; Anan'in, O. B.; Melekhov, A. P.; Gerasimov, I. A.; Bogdanov, G. S.; Novikov, I. K.; Frolova, I. V.; Dzhumaev, P. S.; Рамакоти, Рави Шрираджа; Мелехов, Андрей Петрович; Герасимов, Иван Александрович; Богданов, Глеб Сергеевич; Новиков, Игорь Кимович; Джумаев, Павел Сергеевич
© 2019, Pleiades Publishing, Ltd.The effect of irradiation with soft X-rays produced by a laser plasma source equipped with an X-ray concentrator on the properties of the CdHgTe semiconductor are investigated. For this purpose, the mass concentration of atoms in the near-surface layer of the material is measured. It is demonstrated that the action of soft X-ray radiation leads to change in the solid-solution composition at the surface via a nonthermal mechanism and generates surface defects.