Nikolay Dovzhenko - Academia.edu (original) (raw)

Papers by Nikolay Dovzhenko

Research Square (Research Square), Mar 1, 2021

The paper presents the results of studies of the structure and properties of a wire with a diamet... more The paper presents the results of studies of the structure and properties of a wire with a diameter of 0.5 mm from an alloy of the Al-REM system with a rare-earth metal content of 7-9%. Wire obtained as a result of the implementation of the technology of its manufacture using the methods of casting into an electromagnetic mold (EMM), continuous extruding and drawing. The rheological properties of the metal of continuously cast round billets from the experimental alloy obtained using an electromagnetic mold are determined. The modeling and analytical assessment of the possibility of carrying out the process of combined rolling-extruding (CRE) of such billets in a closed boxtype roll groove of a continuous extruding unit are carried out. The features of metal shaping have been studied. The temperature-speed and technological parameters was found at which the CRE process can be carried out in a stable mode of operation. Data have been obtained for the forces acting on the die and rolls and the moments on the rolls during rolling-extruding. The results of experimental studies of the process of obtaining longish deformed semi-finished products from an experimental alloy on the laboratory unit CRE-200 and the pilot plant unit CRE-400 are presented. The structure of the metal has been studied; data on the ultimate tensile strength, yield strength, relative elongation, and electrical resistivity of hot-extruded rods and wires in cold-worked and annealed states have been obtained. It was found that the proposed processing modes make it possible to obtain by the method of combined rolling-extruding rods with a diameter of 9 mm in industrial conditions from longish billets with a diameter of 18 mm, cast by means of EMM. Wire in a cold-worked and annealed state with a diameter of 0.5 obtained by drawing from the rods with a diameter of 9 mm from an experimental alloy of the Al-REM system containing 7-9 rare earth metals with the required physical and mechanical properties.

International Journal of Lightweight Materials and Manufacture

Приведены физико-химические закономерности взаимодействия щелочного и кислого силикатных растворо... more Приведены физико-химические закономерности взаимодействия щелочного и кислого силикатных растворов присадочных компонентов с вольфрамовыми ангидридами. Предложенная технология пропитки промышленного синего оксида вольфрама кислым алюмосиликатным раствором позволяет получать вольфрамовую проволоку с высокой эффективностью. Ключевые слова: присадочные компоненты, силикатные растворы, механизм, кинетика, взаимодействие, вольфрамовые ангидриды, технология. Введение Использование синего оксида вольфрама (СОВ) в мировой промышленности для производства электровакуумных приборов началось в конце 80-х годов XX века, и все это время присадочные компоненты вводятся в вольфрамовые ангидриды в виде коллоидных щелочных растворов силикатов. Установлено [1-3], что введение оксида калия в вольфрам позволяет получать проволоку со стапельной кристаллической структурой, обеспечивающей продолжительность и надежность эксплуатации электронных и электровакуумных устройств. Основными недостатками щелочных растворов присадочных компонентов являются необходимость их нейтрализации кислотой для введения кислых солей микроприсадок (AlCl 3 , LaCl 3 , Th(NO 3) 4 и др.) и неравномерное распределение присадок по поверхности вольфрамовых оксидов. Промышленный синий оксид вольфрама (ПСОВ) кроме WO 2,9 содержит различные вольфрамовые оксиды, его состав зависит от областей применения и определяется условиями прокалки паравольфрамата аммония (ПВА). ПСОВ, полученный прокаливанием ПВА в восстановительной атмосфере водорода, состоит в основном из трех оксидов: А 0,33 WO 3 , (где А-NH 4 + , NH 3)-аммониевая вольфрамовая бронза (АВБ), WO 2,9 и WO 3 [4, 5]. В атмосфере со значительной восстановительной способностью аммониевая вольфрамовая бронза (АВБ) превращается в WO 2,9 , а затем в WO 2 [6].

Вестник Сибирского государственного аэрокосмического университета им. академика М.Ф. Решетнева, 2006

Цветные металлы, Sep 30, 2019

Журнал зарегистрирован в Федеральной службе по надзору в сфере связи, информационных технологий и... more Журнал зарегистрирован в Федеральной службе по надзору в сфере связи, информационных технологий и массовых коммуникаций (Роскомнадзор) (Свидетельство ПИ № ФС77-69818 от 29.05.2017 г.). Товарный знак и название «Цветные металлы» являются исключительной собственностью Издательского дома «Руда и Металлы». Материалы, отмеченные «Реклама», публикуются на правах рекламы. За достоверность рекламной информации ответственность несет рекламодатель. Все публикуемые материалы научно-технического характера проходят обязательную стадию рецензирования. За достоверность научно-технической информации ответственность несет автор. За сроки размещения опубликованных статей в базе данных Scopus редакция ответственности не несет. Перепечатка, все виды копирования и воспроизведение материалов, публикуемых в журнале, возможна только с письменного разрешения редакции. При перепечатке ссылка на журнал «Цветные металлы» обязательна.

ABSTRACT The main advantage of multiphase frequency controlled AC drives is that they have more c... more ABSTRACT The main advantage of multiphase frequency controlled AC drives is that they have more control resources than the 3-phase ones. The increase of the inverter system phase number (i.e. the number of the phases) more than five together with the joint application of the phase-pole control method and the classical principle of AC motor frequency control in these systems allow considerable improvement of a number of the drive technical-and-economic characteristics (speed of response, reliability, manufacturing cost, etc)

Журнал Сибирского федерального университета. Техника и технологии, 2013

Обработка сплошных и слоистых материалов, 2012

贵金属, Jul 21, 2012

The researches of new palladium-based alloys have been conducted,and the cast and deformed bars f... more The researches of new palladium-based alloys have been conducted,and the cast and deformed bars for jewels have been obtained.The mechanism of occurrence of welding defects (pore formation) in the production of jewelry chains of silver-containing palladium alloys has been studied.The analysis of the welded joints of the chains,obtained by argon-arc welding,has been carried out,and the properties of metal have been analyzed.Conclusions have been drawn on the possibility of use of the developed palladium alloys,which do not contain silver,for the production of wired semi-products having a low propensity for pore formation in the weld seams.

Russian Journal of Non-ferrous Metals, Mar 1, 2016

We present theoretical and experimental studies on the optical properties of dimers composed of o... more We present theoretical and experimental studies on the optical properties of dimers composed of octahedronshaped, gold nanoparticles. The experimental measurements show that the photoluminescence varies quite dramatically as two octahedra are brought into close proximity. AFM images and optical emission have been recorded for dimers in uncoupled and strongly coupled configurations. The former displays a single emission peak, while the latter shows two peaks with the new feature at longer wavelengths. Calculations indicate that the red-shifted peak originates from a strongly coupled plasmon state that oscillates along the extended axis of the dimer. Theoretically, we investigate the distances over which the dimers couple and find this to be particularly plasmon mode dependent. The anisotropic morphology and sharp apexes contribute significantly to the orientational dependence of the interparticle couplings and field properties.

The International Journal of Advanced Manufacturing Technology, Aug 1, 2022

Izvestiya. Non-Ferrous Metallurgy

In order to simulate the pressing of hollow profiles made from aluminum alloys, the previously de... more In order to simulate the pressing of hollow profiles made from aluminum alloys, the previously developed design algorithms for the pressing tool and the QForm software were utilized. The objective of this study was to enhance the quality and decrease the design timeintervals for pressing tools used in the industrial production of aluminum alloy profiles. A novel design procedure for a combined tool, along with the technology of semi-continuous pressing with welded hollow profiles made from aluminum alloys, was proposed. This was achieved using the QForm software, which enables efficient calculations and adjustments of pressing parameters and tool geometry through a dialog interface. The developed algorithm and design procedures enable the drawing of hollow profiles, technological calculations of pressing parameters, selection of a suitable horizontal hydraulic press, matrix and splitter design, determination of strength parameters, assessment of equipment load, and preparation of wo...

Non-ferrous metals, Dec 29, 2017

The International Journal of Advanced Manufacturing Technology, May 26, 2021

Hot deformation behavior of the new alloy 1580 sparingly doped with scandium (Al-5Mg-0.6Mn-0.10Sc... more Hot deformation behavior of the new alloy 1580 sparingly doped with scandium (Al-5Mg-0.6Mn-0.10Sc-0.11Zr) was studied under the deformation temperature ranging from 350 to 450 °C and strain rate ranging from 0.01 to 10 s−1. Hot deformation by uniaxial compression and torsion was carried out on a Gleeble 3800 thermomechanical simulator. Hot deformation of the alloy 1580 is accompanied by dynamic softening with the establishment of a balance between the rates of nucleation and annihilation of dislocations. Alloy flow stresses increase with increasing strain rate and decreasing temperature. The experimental results for the new alloy are in full agreement with the known concepts that the combined effect of temperature and strain rate on the deformation behavior of metallic materials is described by the Zener-Hollomon parameter. The deformation activation energy of the alloy obtained by the regression analysis of steady-state flow stresses is 175.7 kJ/mol. When using the steady-state flow stresses normalized to the shear modulus, the deformation activation energy is 148.8 kJ/mol and is close to the activation energy of self-diffusion of aluminum. Analytical expressions are obtained for steady-state flow stresses as a function of the Zener-Hollomon parameter, which make it possible to predict the deformation resistance of the alloy 1580 in a wide range of temperatures and strain rates. This result is important for FEM modeling and for the choice of temperature and stain rate of hot deformation of the alloy under study. Comparison with the literature data showed that in the region of high temperatures and low strain rates, the flow stresses are weakly dependent on the scandium content in the alloy. However, with a decrease in the temperature and an increase in the strain rate, an increase in the scandium content in the alloys leads to a noticeable increase in the flow stresses. In torsion tests, a sharp increase in the ductility of the alloy is observed at a temperature of about 400 °C. One of its probable causes may be dissolution of particles Al3(Sc,Zr) during hot deformation in this high-temperature region.

Проанализировано производство длинномерной продукции из цветных металлов и сплавов. Разработаны н... more Проанализировано производство длинномерной продукции из цветных металлов и сплавов. Разработаны новые модели и предложены конструкции агрегатов совмещенной обработки.

Research Square (Research Square), Sep 2, 2021

The results of studies of the structure and properties of semi-nished products from aluminum and ... more The results of studies of the structure and properties of semi-nished products from aluminum and its alloys, obtained with the use of cast-free rolling-extruding are presented. It has been found that the rods obtained by the high-speed crystallization-deformation technology by the direct rolling-extrusion method have a stable ultra ne subgrain structure, which makes it possible to use them as modi ers. Experimental studies have been carried out, which con rmed the assumption that the initial structure of the modifying rod affects the melt. It was revealed that the size and density of distribution of additional crystallization centers formed in the volume of the melt based on clusters are inherited from the original subgrain structure of the modifying rod made of aluminum or its alloys. Metallographic studies have also shown that the subsequent severe plastic deformation by equal-channel angular extruding of rods obtained by direct rolling-extruding from an experimental alloy of the composition Al-0.2Zr-0.2Fe-0.4Mg makes it possible to achieve additional strengthening of the metal, since even more re nes its structure, while the average grain size is 647 μm.

Žurnal Sibirskogo federalʹnogo universiteta, Aug 1, 2016

Possibility of using of aluminum A7 instead of A8 to reduce the cost automobile wheel discs, made... more Possibility of using of aluminum A7 instead of A8 to reduce the cost automobile wheel discs, made from alloy AK12 by casting under low pressure is studied. The microstructure and properties of six experimental alloys are investigated. It is found that use of primary aluminum A7 instead of A8 is possible at insertion of a compensator element-manganese in an amount of not more than 0.20-0.25 wt %. at the content of iron is not more than 0.20-0.25 wt. %, that is ratio Fe: Mn has to be equal 1: 1. The mechanical properties demanded GOST 50511-93 are received.

Журнал Сибирского федерального университета. Техника и технологии, Aug 1, 2016

Надежность и долговечность электровакуумных приборов во многом зависят от свойств и качества мате... more Надежность и долговечность электровакуумных приборов во многом зависят от свойств и качества материалов, применяемых для их изготовления. Поэтому вольфрам используется главным образом в виде сплавов, так как чистый вольфрам не удовлетворяет условиям работы и не обеспечивает высокого качества и надежности приборов. Благодаря своим уникальным свойствам вольфрам широко используется в производстве быстрорежущих и специальных сталей, твердых сплавов специального назначения. В последнее время за рубежом количество вольфрама, потребляемого специальными областями техники, увеличивается. В связи с этим к исходным и промежуточным соединениям, используемым для производства изделий из вольфрама и его сплавов, предъявляются повышенные требования по химическому составу и физическим свойствам. В работе [1] изучены условия получения синего оксида вольфрама (СОВ) в водородной и водородно-азотной атмосфере. Нами изучено влияние температуры на степень разложения аммиака, выделяющегося при прокаливании ПВА. Состав образующейся при этом газовой фазы получил название «автогенной» атмосферы. Термодинамические и кинетические исследования процесса получения промышленного СОВ прокалкой ПВА в «автогенной» атмосфере позволили установить механизм и кинетику восстановления WO 3 до WO 2,9 , исследованиями и полупромышленными испытаниями показана высокая скорость получения СОВ из ПВА. Рекомендованы основные параметры процесса.

Цветные металлы, Dec 29, 2016

Research Square (Research Square), Mar 1, 2021

The paper presents the results of studies of the structure and properties of a wire with a diamet... more The paper presents the results of studies of the structure and properties of a wire with a diameter of 0.5 mm from an alloy of the Al-REM system with a rare-earth metal content of 7-9%. Wire obtained as a result of the implementation of the technology of its manufacture using the methods of casting into an electromagnetic mold (EMM), continuous extruding and drawing. The rheological properties of the metal of continuously cast round billets from the experimental alloy obtained using an electromagnetic mold are determined. The modeling and analytical assessment of the possibility of carrying out the process of combined rolling-extruding (CRE) of such billets in a closed boxtype roll groove of a continuous extruding unit are carried out. The features of metal shaping have been studied. The temperature-speed and technological parameters was found at which the CRE process can be carried out in a stable mode of operation. Data have been obtained for the forces acting on the die and rolls and the moments on the rolls during rolling-extruding. The results of experimental studies of the process of obtaining longish deformed semi-finished products from an experimental alloy on the laboratory unit CRE-200 and the pilot plant unit CRE-400 are presented. The structure of the metal has been studied; data on the ultimate tensile strength, yield strength, relative elongation, and electrical resistivity of hot-extruded rods and wires in cold-worked and annealed states have been obtained. It was found that the proposed processing modes make it possible to obtain by the method of combined rolling-extruding rods with a diameter of 9 mm in industrial conditions from longish billets with a diameter of 18 mm, cast by means of EMM. Wire in a cold-worked and annealed state with a diameter of 0.5 obtained by drawing from the rods with a diameter of 9 mm from an experimental alloy of the Al-REM system containing 7-9 rare earth metals with the required physical and mechanical properties.

International Journal of Lightweight Materials and Manufacture

Приведены физико-химические закономерности взаимодействия щелочного и кислого силикатных растворо... more Приведены физико-химические закономерности взаимодействия щелочного и кислого силикатных растворов присадочных компонентов с вольфрамовыми ангидридами. Предложенная технология пропитки промышленного синего оксида вольфрама кислым алюмосиликатным раствором позволяет получать вольфрамовую проволоку с высокой эффективностью. Ключевые слова: присадочные компоненты, силикатные растворы, механизм, кинетика, взаимодействие, вольфрамовые ангидриды, технология. Введение Использование синего оксида вольфрама (СОВ) в мировой промышленности для производства электровакуумных приборов началось в конце 80-х годов XX века, и все это время присадочные компоненты вводятся в вольфрамовые ангидриды в виде коллоидных щелочных растворов силикатов. Установлено [1-3], что введение оксида калия в вольфрам позволяет получать проволоку со стапельной кристаллической структурой, обеспечивающей продолжительность и надежность эксплуатации электронных и электровакуумных устройств. Основными недостатками щелочных растворов присадочных компонентов являются необходимость их нейтрализации кислотой для введения кислых солей микроприсадок (AlCl 3 , LaCl 3 , Th(NO 3) 4 и др.) и неравномерное распределение присадок по поверхности вольфрамовых оксидов. Промышленный синий оксид вольфрама (ПСОВ) кроме WO 2,9 содержит различные вольфрамовые оксиды, его состав зависит от областей применения и определяется условиями прокалки паравольфрамата аммония (ПВА). ПСОВ, полученный прокаливанием ПВА в восстановительной атмосфере водорода, состоит в основном из трех оксидов: А 0,33 WO 3 , (где А-NH 4 + , NH 3)-аммониевая вольфрамовая бронза (АВБ), WO 2,9 и WO 3 [4, 5]. В атмосфере со значительной восстановительной способностью аммониевая вольфрамовая бронза (АВБ) превращается в WO 2,9 , а затем в WO 2 [6].

Вестник Сибирского государственного аэрокосмического университета им. академика М.Ф. Решетнева, 2006

Цветные металлы, Sep 30, 2019

Журнал зарегистрирован в Федеральной службе по надзору в сфере связи, информационных технологий и... more Журнал зарегистрирован в Федеральной службе по надзору в сфере связи, информационных технологий и массовых коммуникаций (Роскомнадзор) (Свидетельство ПИ № ФС77-69818 от 29.05.2017 г.). Товарный знак и название «Цветные металлы» являются исключительной собственностью Издательского дома «Руда и Металлы». Материалы, отмеченные «Реклама», публикуются на правах рекламы. За достоверность рекламной информации ответственность несет рекламодатель. Все публикуемые материалы научно-технического характера проходят обязательную стадию рецензирования. За достоверность научно-технической информации ответственность несет автор. За сроки размещения опубликованных статей в базе данных Scopus редакция ответственности не несет. Перепечатка, все виды копирования и воспроизведение материалов, публикуемых в журнале, возможна только с письменного разрешения редакции. При перепечатке ссылка на журнал «Цветные металлы» обязательна.

ABSTRACT The main advantage of multiphase frequency controlled AC drives is that they have more c... more ABSTRACT The main advantage of multiphase frequency controlled AC drives is that they have more control resources than the 3-phase ones. The increase of the inverter system phase number (i.e. the number of the phases) more than five together with the joint application of the phase-pole control method and the classical principle of AC motor frequency control in these systems allow considerable improvement of a number of the drive technical-and-economic characteristics (speed of response, reliability, manufacturing cost, etc)

Журнал Сибирского федерального университета. Техника и технологии, 2013

Обработка сплошных и слоистых материалов, 2012

贵金属, Jul 21, 2012

The researches of new palladium-based alloys have been conducted,and the cast and deformed bars f... more The researches of new palladium-based alloys have been conducted,and the cast and deformed bars for jewels have been obtained.The mechanism of occurrence of welding defects (pore formation) in the production of jewelry chains of silver-containing palladium alloys has been studied.The analysis of the welded joints of the chains,obtained by argon-arc welding,has been carried out,and the properties of metal have been analyzed.Conclusions have been drawn on the possibility of use of the developed palladium alloys,which do not contain silver,for the production of wired semi-products having a low propensity for pore formation in the weld seams.

Russian Journal of Non-ferrous Metals, Mar 1, 2016

We present theoretical and experimental studies on the optical properties of dimers composed of o... more We present theoretical and experimental studies on the optical properties of dimers composed of octahedronshaped, gold nanoparticles. The experimental measurements show that the photoluminescence varies quite dramatically as two octahedra are brought into close proximity. AFM images and optical emission have been recorded for dimers in uncoupled and strongly coupled configurations. The former displays a single emission peak, while the latter shows two peaks with the new feature at longer wavelengths. Calculations indicate that the red-shifted peak originates from a strongly coupled plasmon state that oscillates along the extended axis of the dimer. Theoretically, we investigate the distances over which the dimers couple and find this to be particularly plasmon mode dependent. The anisotropic morphology and sharp apexes contribute significantly to the orientational dependence of the interparticle couplings and field properties.

The International Journal of Advanced Manufacturing Technology, Aug 1, 2022

Izvestiya. Non-Ferrous Metallurgy

In order to simulate the pressing of hollow profiles made from aluminum alloys, the previously de... more In order to simulate the pressing of hollow profiles made from aluminum alloys, the previously developed design algorithms for the pressing tool and the QForm software were utilized. The objective of this study was to enhance the quality and decrease the design timeintervals for pressing tools used in the industrial production of aluminum alloy profiles. A novel design procedure for a combined tool, along with the technology of semi-continuous pressing with welded hollow profiles made from aluminum alloys, was proposed. This was achieved using the QForm software, which enables efficient calculations and adjustments of pressing parameters and tool geometry through a dialog interface. The developed algorithm and design procedures enable the drawing of hollow profiles, technological calculations of pressing parameters, selection of a suitable horizontal hydraulic press, matrix and splitter design, determination of strength parameters, assessment of equipment load, and preparation of wo...

Non-ferrous metals, Dec 29, 2017

The International Journal of Advanced Manufacturing Technology, May 26, 2021

Hot deformation behavior of the new alloy 1580 sparingly doped with scandium (Al-5Mg-0.6Mn-0.10Sc... more Hot deformation behavior of the new alloy 1580 sparingly doped with scandium (Al-5Mg-0.6Mn-0.10Sc-0.11Zr) was studied under the deformation temperature ranging from 350 to 450 °C and strain rate ranging from 0.01 to 10 s−1. Hot deformation by uniaxial compression and torsion was carried out on a Gleeble 3800 thermomechanical simulator. Hot deformation of the alloy 1580 is accompanied by dynamic softening with the establishment of a balance between the rates of nucleation and annihilation of dislocations. Alloy flow stresses increase with increasing strain rate and decreasing temperature. The experimental results for the new alloy are in full agreement with the known concepts that the combined effect of temperature and strain rate on the deformation behavior of metallic materials is described by the Zener-Hollomon parameter. The deformation activation energy of the alloy obtained by the regression analysis of steady-state flow stresses is 175.7 kJ/mol. When using the steady-state flow stresses normalized to the shear modulus, the deformation activation energy is 148.8 kJ/mol and is close to the activation energy of self-diffusion of aluminum. Analytical expressions are obtained for steady-state flow stresses as a function of the Zener-Hollomon parameter, which make it possible to predict the deformation resistance of the alloy 1580 in a wide range of temperatures and strain rates. This result is important for FEM modeling and for the choice of temperature and stain rate of hot deformation of the alloy under study. Comparison with the literature data showed that in the region of high temperatures and low strain rates, the flow stresses are weakly dependent on the scandium content in the alloy. However, with a decrease in the temperature and an increase in the strain rate, an increase in the scandium content in the alloys leads to a noticeable increase in the flow stresses. In torsion tests, a sharp increase in the ductility of the alloy is observed at a temperature of about 400 °C. One of its probable causes may be dissolution of particles Al3(Sc,Zr) during hot deformation in this high-temperature region.

Проанализировано производство длинномерной продукции из цветных металлов и сплавов. Разработаны н... more Проанализировано производство длинномерной продукции из цветных металлов и сплавов. Разработаны новые модели и предложены конструкции агрегатов совмещенной обработки.

Research Square (Research Square), Sep 2, 2021

The results of studies of the structure and properties of semi-nished products from aluminum and ... more The results of studies of the structure and properties of semi-nished products from aluminum and its alloys, obtained with the use of cast-free rolling-extruding are presented. It has been found that the rods obtained by the high-speed crystallization-deformation technology by the direct rolling-extrusion method have a stable ultra ne subgrain structure, which makes it possible to use them as modi ers. Experimental studies have been carried out, which con rmed the assumption that the initial structure of the modifying rod affects the melt. It was revealed that the size and density of distribution of additional crystallization centers formed in the volume of the melt based on clusters are inherited from the original subgrain structure of the modifying rod made of aluminum or its alloys. Metallographic studies have also shown that the subsequent severe plastic deformation by equal-channel angular extruding of rods obtained by direct rolling-extruding from an experimental alloy of the composition Al-0.2Zr-0.2Fe-0.4Mg makes it possible to achieve additional strengthening of the metal, since even more re nes its structure, while the average grain size is 647 μm.

Žurnal Sibirskogo federalʹnogo universiteta, Aug 1, 2016

Possibility of using of aluminum A7 instead of A8 to reduce the cost automobile wheel discs, made... more Possibility of using of aluminum A7 instead of A8 to reduce the cost automobile wheel discs, made from alloy AK12 by casting under low pressure is studied. The microstructure and properties of six experimental alloys are investigated. It is found that use of primary aluminum A7 instead of A8 is possible at insertion of a compensator element-manganese in an amount of not more than 0.20-0.25 wt %. at the content of iron is not more than 0.20-0.25 wt. %, that is ratio Fe: Mn has to be equal 1: 1. The mechanical properties demanded GOST 50511-93 are received.

Журнал Сибирского федерального университета. Техника и технологии, Aug 1, 2016

Надежность и долговечность электровакуумных приборов во многом зависят от свойств и качества мате... more Надежность и долговечность электровакуумных приборов во многом зависят от свойств и качества материалов, применяемых для их изготовления. Поэтому вольфрам используется главным образом в виде сплавов, так как чистый вольфрам не удовлетворяет условиям работы и не обеспечивает высокого качества и надежности приборов. Благодаря своим уникальным свойствам вольфрам широко используется в производстве быстрорежущих и специальных сталей, твердых сплавов специального назначения. В последнее время за рубежом количество вольфрама, потребляемого специальными областями техники, увеличивается. В связи с этим к исходным и промежуточным соединениям, используемым для производства изделий из вольфрама и его сплавов, предъявляются повышенные требования по химическому составу и физическим свойствам. В работе [1] изучены условия получения синего оксида вольфрама (СОВ) в водородной и водородно-азотной атмосфере. Нами изучено влияние температуры на степень разложения аммиака, выделяющегося при прокаливании ПВА. Состав образующейся при этом газовой фазы получил название «автогенной» атмосферы. Термодинамические и кинетические исследования процесса получения промышленного СОВ прокалкой ПВА в «автогенной» атмосфере позволили установить механизм и кинетику восстановления WO 3 до WO 2,9 , исследованиями и полупромышленными испытаниями показана высокая скорость получения СОВ из ПВА. Рекомендованы основные параметры процесса.

Цветные металлы, Dec 29, 2016