Персона: Джумаев, Павел Сергеевич
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Институт ядерной физики и технологий
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.
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Руководитель научной группы "Лаборатория ионно-плазменной и ионно-пучковой обработки материалов"
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Павел Сергеевич
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- ПубликацияТолько метаданныеNonthermal 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.
- ПубликацияТолько метаданныеFeatures of creating wear-resistant anti-corrosion coatings with a barrier layer on fragments of fuel claddings from E110 o.ch.(2020) Novikov, V. V.; Kuznetsov, V. I.; Fedotov, P. V.; Krivobokov, V. P.; Kalin, B. A.; Yashin, A. S.; Dzhumaev, P. S.; Safonov, D. A.; Korenevsky, E. L.; Fedorov, D. A.; Uglov, V. V.; Яшин, Александр Сергеевич; Джумаев, Павел Сергеевич; Кореневский, Егор Леонидович; Углов, Владимир Васильевич© Published under licence by IOP Publishing Ltd.Results of the development of protective chromium-containing coatings based on the FeCrNi and CrNi systems for fuel claddings within framework of the accident tolerant fuel (ATF) are presented in this paper. Coatings were deposited by the outer surface of cladding tubes fragments from E110 o.ch. alloy (sponge-based Zr-1%Nb) up to 500 mm length by complex ion-plasma treatment on ILUR-03 and KVK-10 installations. The results of the control tests carried out in high-temperature steam at the GAZPAR bench at 1200 °C up to 400 s showed that Cr-FeCrNi-Cr and Cr-CrNi-Cr coatings reduce total oxygen penetration into the alloy from 144 to 98 and 55 μm, respectively and Cr-CrNi-Cr coatings with a Mo barrier layer completely block the diffusion of oxygen into the material.
- ПубликацияТолько метаданныеStudy of Ti-Zr-Nb-Be filler metal interaction with silicon carbide based ceramics during brazing process(2020) Eroshenko, A. A.; Ivannikov, А. A.; Fedotov, I. V.; Suchkov, A. N.; Dzhumaev, P. S.; Sevryukov, O. N.; Иванников, Александр Александрович; Федотов, Иван Владимирович; Сучков, Алексей Николаевич; Джумаев, Павел Сергеевич; Севрюков, Олег Николаевич© Published under licence by IOP Publishing Ltd.This work is devoted to an analysis of the composition of a silicon carbide based ceramic brazed seam as a result of its interaction with rapidly quenched titanium-zirconium-niobium-beryllium filler metal. Structural-phase studies based on EDX and EBSD analysis, mechanical shear tests, and microhardness measurements of brazed joints were carried out. It was shown that titanium, zirconium, and niobium silicides as well as particles of titanium carbosilicides and silicon carbides in the silicon matrix are formed in the brazed seam, probably because of the presence of free silicon in the base material, which leads to increasing joint microhardness and unstable shear strength results.
- ПубликацияТолько метаданныеThermal fatigue damage of steel joints brazed with various nickel filler metals(2019) Penyaz, M. A.; Ivannikov, A. A.; Kalin, B. A.; Dzhumaev, P. S.; Иванников, Александр Александрович; Джумаев, Павел Сергеевич© E. V. Aryshnskii, V. Yu. Bazhin, R. Kawalla, 2019.Demands on the properties of constructions are constantly being increased and the technology of producing permanent joints is crucial for advancement of the high-tech industry. This investigation focuses on thermal fatigue of austenitic steel joints, brazed with nickel filler metals based on Ni - Cr - Si system. This type of fatigue has nonmechanical origin and arises from the cyclic variation of thermal stresses with temperature changes. For investigation selected temperature range is: From room temperature to 450 oC (low-cycle fatigue). Due to inhomogeneous thermal expansion or compression during thermal fatigue, thermal stresses and deformation arise and lead to microstructural changes in the joint zone. This can have a strong effect on the mechanical characteristics of the joint. Therefore, it is important to investigate the properties of the brazed seam after thermal cycling. In this work samples brazed various filler metals before and after thermocycling were evaluated using various methods. The microstructures were investigated and analysis by energy-dispersive X-ray spectroscopy (EDS) of the diffusion zone was carried out using electron microscope. The main regularities of the structure-phase state formation studied using electron backscatter diffraction (EBSD). Standard tests for the tensile strength of the samples were carried out. The result of this research is the prediction of the durability and reliability of brazed steel constructions operating under conditions of low-cycle temperature changes.
- ПубликацияТолько метаданныеApplying Scanning Contact Potentiometry for Monitoring Incipient Cracks in Steels(2019) Surin, V. I.; Polskij, V. I.; Osintsev, A. V.; Dzhumaev, P. S.; Сурин, Виталий Иванович; Польский, Валерий Игоревич; Осинцев, Андрей Вениаминович; Джумаев, Павел Сергеевич© 2019, Pleiades Publishing, Ltd. The processes of formation and growth of an incipient crack in EI847 steel have been studied by uniaxial constant-load tension testing on an INSTRON-5982 tensile testing machine using scanning contact potentiometry. The nucleus was detected at the sample surface within the yield strength domain and was stably monitored based on the readings of apparatus under higher loads until the moment of destruction.
- ПубликацияТолько метаданныеStudy of Mechanical Characteristics of Stainless Steel Samples Obtained by Direct Laser Deposition(2019) Ishkinyaev, E. D.; Petrovskiy, V. N.; Polskiy, V. I.; Dzhumaev, P. S.; Sergeev, K. L.; Shchekin, A. S.; Panov, D. V.; Ushakov, D. V.; Ишкиняев, Эмиль Дамирович; Петровский, Анатолий Николаевич; Польский, Валерий Игоревич; Джумаев, Павел Сергеевич; Щекин, Александр Сергеевич© 2019, Pleiades Publishing, Ltd.The paper presents the results of mechanical tensile tests and microhardness of samples obtained from stainless steel 316L powder by direct laser deposition. The strength characteristics of the deposited samples are better than those of rolled ones obtained in the traditional way. The material strength is reduced and its plasticity is increased with the growth of the laser radiation power during deposition. The obtained regularities are explained by analysis of the microstructure. It is found that the hardness of the cladding is substantially higher than that of the substrate material with the corresponding composition. This is a consequence of hardening of each layer during deposition of the next layer and formation of nanosized spherical inclusions representing oxides of metals that make up the powder in the sample bulk. The density of these particles affects the overall hardness of the material and depends on the radiation power supplied. Individual properties of the material for various applications can be modified by appropriate selection of technological parameters of the printing process.
- ПубликацияТолько метаданныеAl2O3nanostructured gas sensitive material for silicon based low power thermocatalytic sensor(2019) Barsony, I.; Ducso, C.; Biro, F.; Samotaev, N. N.; Pisliakov, A.; Gorshkova, A.; Dzhumaev, P. S.; Самотаев, Николай Николаевич; Джумаев, Павел Сергеевич© 2019 Elsevier Ltd.Micro-catalytic gas sensors are essential devices for detection of combustive gases up to lower explosion limit (LEL). Micro-catalytic gas sensors capable to detect hydrocarbons below 50'mW power consumption at 550'°C operation temperature were developed by using a novel gas sensing material technique. Experiments were aiming at deposition of controlled volume and structure of the catalyst. Constant current method in a Wheatstone-bridge configuration was applied in functional tests of developed Al2O3 catalysts.
- ПубликацияТолько метаданныеDiffusion brazing of stainless steels influence of Ni-B filler alloy composition(2021) Ivannikov, A. A.; Penyaz, M. A.; Dzhumaev, P. S.; Bachurina, D. M.; Sevryukov, O. N.; Иванников, Александр Александрович; Джумаев, Павел Сергеевич; Севрюков, Олег Николаевич© 2020, International Institute of Welding.Stainless austenitic (0.12C-18Cr-10Ni-Ti, wt-%) and ferritic-martensitic (0.16C-12Cr-Mo-Si-V-Nb-B, wt-%) steels were joined by transient liquid phase diffusion bonding (also called diffusion brazing) with the filler metals based on Ni-Cr-Si-(Fe)-B at 1160 °C for different bonding times from 15 to 40 min. It is shown that the braze joints have a heterogeneous diffusion zone with a boride network which is formed during isothermal solidification. The influence of the filler metals composition on the joint microstructure and tensile strength was studied. It is established that the initial concentration of boron and chromium in the filler metal plays an important role in the formation of the microstructure. It is shown that the use of the filler metal with the optimized composition of Ni-20Cr-7.5Si-4.5Fe-1.5B makes it possible to obtain the most homogeneous structure, leading to the best tensile strength of the joint of about 500 ± 40 MPa.
- ПубликацияТолько метаданныеCombination of ceramic laser micromachining and printed technology as a way for rapid prototyping semiconductor gas sensors(2021) Fritsch, M.; Mosch, S.; Vinnichenko, M.; Trofimenko, N.; Samotaev, N.; Oblov, K.; Dzhumaev, P.; Самотаев, Николай Николаевич; Облов, Константин Юрьевич; Джумаев, Павел Сергеевич© 2021 by the authors. Licensee MDPI, Basel, Switzerland.The work describes a fast and flexible micro/nano fabrication and manufacturing method for ceramic Micro-electromechanical systems (MEMS)sensors. Rapid prototyping techniques are demonstrated for metal oxide sensor fabrication in the form of a complete MEMS device, which could be used as a compact miniaturized surface mount devices package. Ceramic MEMS were fabricated by the laser micromilling of already pre-sintered monolithic materials. It has been demonstrated that it is possible to deposit metallization and sensor films by thick-film and thin-film methods on the manufactured ceramic product. The results of functional tests of such manufactured sensors are presented, demonstrating their full suitability for gas sensing application and indicating that the obtained parameters are at a level comparable to those of industrial produced sensors. Results of design and optimization principles of applied methods for micro-and nanosystems are discussed with regard to future, wider application in semiconductor gas sensors prototyping.
- ПубликацияТолько метаданныеSilicon MEMS Thermocatalytic Gas Sensor in Miniature Surface Mounted Device Form(2021) Samotaev, N.; Samotaev, N; Dzhumaev, P.; Oblov, K.; Pisliakov, A.; Самотаев, Николай Николаевич; Джумаев, Павел Сергеевич; Облов, Константин Юрьевич; Образцов, Иван СергеевичA reduced size thermocatalytic gas sensor was developed for the detection of methane over the 20% of the explosive concentration. The sensor chip is formed from two membranes with a 150 mu m diameter heated area in their centers and covered with highly dispersed nano-sized catalyst and inert reference, respectively. The power dissipation of the chip is well below 70 mW at the 530 degrees C maximum operation temperature. The chip is mounted in a novel surface mounted metal-ceramic sensor package in the form-factor of SOT-89. The sensitivity of the device is 10 mV/v%, whereas the response and recovery times without the additional carbon filter over the chip are <500 ms and <2 s, respectively. The tests have shown the reliability of the new design concerning the hotplate stability and massive encapsulation, but the high degradation rate of the catalyst coupled with its modest chemical power limits the use of the sensor only in pulsed mode of operation. The optimized pulsed mode reduces the average power consumption below 2 mW.