№1(3) 2015

Постійне посилання зібрання

https://eir.nuos.edu.ua/handle/123456789/3335

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Зараз показуємо 1 - 7 з 7

The 18H2N4MA steel strength characteristics increase = Повышение прочностных характеристик стали 18Х2Н4МА
(2015-11-09) Dubovoy, A. N.; Дубовой, А. Н.; Volkov, G. V.; Волков, Г. В.; Zhdanov, A. A.; Жданов, А. А.
The article considers the impact of prerecrystallization heat treatment on the hardness, strength and fatigue strength of the 18H2N4MA steel after preliminary shot blasting. It is experimentally established that as the result of prerecrystallization heat treatment at 500 °C with 3 minutes delay the layer with an increased measure of hardness (hardness is increased by 42 %) is formed on the 18H2N4MA steel surface after the preliminary shot blasting. The 18H2N4MA steel shot blasting causes the formation of compressive stresses in the surface layer, the subsequent prerecrystallization heat treatment does not change the nature of the residual stress, but only leads to the decrease in the absolute values, preserving the work-hardened layer depth. The prerecrystallization heat treatment leads to an increase in fatigue strength of the 18H2N4MA steel about 2.7 times compared with the shot blasting and increase of the tensile strength by 11 %, with plasticity indexes substantially constant. Such an increase in the strength indicators of the 18H2N4MA steel as a result of prerecrystallization heat treatment is caused by the formation of the substructures with shredded precinct in the steel surface layer. The given assumption is confirmed by the X-ray diffraction and electron metallography results. After prerecrystallization heat treatment the partial subgrains grinding from 222 ÷ 133 nm after shot blasting to 90 ÷ 49 nm is observed in the 18H2N4MA steel structure. = Исследовано влияние предрекристаллизационной термической обработки на предел прочности, твердость и усталостную прочность стали 18Х2Н4МА после дробеструйной обработки.
Acquisition of technical vocabulary and shipbuilding terminology in chinese didactic environment = Изучение общетехнической и судостроительной терминологии в китайскоязычной дидактической среде
(2015-11-09) Chernitskiy, V. B.; Черницкий, В. Б.; Jang, Xilai; Жэнг, Ксилаи
Didactic problems dealing with masterіng English scientific and shipbuilding terminology by Chinese students have been studied. The study deals with a particular issue of rendering educational services in English as an intermediary language in the Chinese teaching environment. This issue mainly concerns the improvement of teaching process through the development of methodological materials for mastering the fundamental terminology of shipbuilding in the foreign language environment. The key principle for our terminological array selection was based on the intelligible assumption: due to the extension of integration processes of science and technology development and globalization intensification, that are both reflected in the languages of our everyday life, the main attention is to be paid to the mastering of specialized terminology, that of shipbuilding theory and practice fundamentals. It logically resulted in devoting less preference to the general scientific notions and terms as the latter are easily conceived as ‘internationalisms’ in almost all European languages. To substantiate such an assumption we relied on general ways of assimilation in Chinese of the so called ‘internationalisms’ and borrowings from English. In order to prove the validity of this obvious approach we had attempted a brief experiment which demonstrated complete inconsistency of our approach. Thus, the data obtained allow us to solve the aboveindicated problem of CLIL teaching in Chinese didactic environment. = Рассмотрены вопросы усвоения студентами общенаучной и специальной технической терминологии в условиях китайскоязычной дидактической среды. Предложена методика подготовки учебных материалов для повышения качества учебного процесса в среде китайских судостроительных колледжей и ВНЗ.
Influence of electric impulse impact on the mechanical properties of plasma coatings = Влияние электроимпульсного воздействия на механические свойства плазменных покрытий
(2015-11-09) Dubovoy, A. N.; Дубовой, А. Н.; Karpechenko, A. A.; Карпеченко, А. А.; Bobrov, M. N.; Бобров, М. Н.; Novikov, A. A.; Новиков, А. А.
The appliance of electropulse impacton the spraying distances to enhance the properties of plasma sprayed coatingsis discussed. The aim of research is to set the impact of high-voltage electrical pulses on the process of applying the plasma coatings and their mechanical properties.The structure and mechanical propertiessuch ashardness, bond strength, wear resistance of bronze plasma sprayed coating obtained using the electropulse impact are studied experimentally. Set the effect of The enhancement of mechanical properties of coatings obtained by grinding their structure and improving the speed of sprayed particles are set. The research results can be applied in thetechnology of repair and restoration of machines elements and mechanisms.The fixed effect allows us solving the problem of providing the high quality plasma sprayed coatings. = Исследовано влияние наложения электрических импульсов при плазменном напылении на механические свойства покрытий.
Influence of high-frequency electrode vibrations on the geometry of penetration at automatic submerged arc cladding = Влияние высокочастотных колебаний электрода на геометрию проплавления при автоматической наплавке под флюсом
(2015-11-09) Dragan, S. V.; Драган, С. В.; Yaros, Yu. A.; Ярос, Ю. А.; Simutenkov, I. V.; Trembich, V. Ya.; Трембич, В. Я.
High-frequency oscillations electrodes for automatic submerged arc cladding, along with providing managed metal transfer and improved productivity melting electrode — an effective management tool geometry penetration. The purpose of this work-design and experimental evaluation of the influence of the geometry of penetration of the high-frequency oscillations electrodes in submerged arc cladding. Based on the analysis of the speed of the arc for high-frequency oscillations electrodes found that with increasing amplitude of the oscillation frequency increases and the average speed of the electrode tip and arc cladding. When vibrations of the electrode tip with a frequency of 1 Hz and amplitude of 10 mm can be regarded as an arc of a fast-heating source. The speed of movement of such a source is ten times greater than the rate of propagation of heat in the base metal. Therefore, electrode oscillation with amplitude greater than the width of the weld bead results in loss of depth and area of penetration during cladding with high-frequency oscillations electrodes. This pattern is confirmed by calculations using the model of the moving heat source of finite width. Based on the ratio between the speed of movement of the heat source and heat propagation in base metal, established three areas of influence of the frequency and amplitude of the high-frequency oscillations electrodes on the technological characteristics of the arc process and the geometry of the metal penetration zone: 1) the influence of the geometry of the penetration zone and there is no transfer of metal; 2) melting of the electrode performance, the nature and geometry of the managed transfer penetration zone defined by the relation between frequency and amplitude of vibration; 3) the quality of the formation of the deposited layer decreases sharply due to violation of the stability of the arc at high speed of its movement. Based on the records of thermal cycles points in the heating zone confirmed the influence of the geometry of the high-frequency oscillations electrodes penetration and the propagation of heat in the base metal. Found that variations in cladding a temperature of 250 Hz test points, located transversely at a distance of 6 mm from the roll axis at 60 °C (15 %) than the value obtained by cladding without vibration. This is because increasing the amplitude of the oscillations increases the heat flow dispersion zone decreases weld metal bath superheat increases the thermal efficiency of the fusion process and, as a consequence, increases the penetration area. This pattern persists as long as the heat surrounding layers of solid based metal will not exceed the influx of heat from the heating source. Further growth of the oscillation amplitude will increase the width of the weld pool and reduce the depth and area of penetration. The dependence is confirmed by the results of the calculation. Established laws allow by calculation to determine the size and shape of the penetration zone for automatic submerged arc cladding with the high-frequency oscillations electrodes, as well as serve as a basis for selecting parameters oscillation mode to control the geometry of the deposited layer. = Приведены результаты исследования влияния скорости перемещения источника нагрева — сварочной дуги при автоматической наплавке под флюсом с высокочастотными колебаниями электрода на температурное поле в основном металле и геометрию зоны проплавления. Расчетным путем определены области, соответствующие различному эффекту от воздействия параметров поперечных высокочастотных колебаний электрода на устойчивость дуги, характер переноса металла и геометрию зоны проплавления.
Key factors of competitive shipbuilding programs in difficult economic conditions = Ключові фактори програм розвитку конкурентоспроможного суднобудування в складних економічних умовах
(2015-11-09) Slobodyan, S. O.; Слободян, С. О.
The experience of European and Asia-Pacific countries leading in the creation and effective implementation of national programs of the competitive shipbuilding development in difficult economic conditions has been analyzed in the article. The conditions were formed in the industry as a result of the global financial and economic crisis. The influence of the socalled conjuncture factors on the uneven development of the global shipbuilding market is considered; these factors reflect the imbalance between the supply of the shipbuilding companies and the demand of the ship-owners for vessels of various types and tonnage. The relationship of the shipbuilding overcapacity with the mismatch of the cyclicality of shipbuilding and shipping markets is shown. The key factors of effective formulation of programs of the competitive shipbuilding development determined for their further consideration when improving the domestic support system of management decision making in difficult economic conditions. = Проанализирован опыт ведущих европейских и азиатско-тихоокеанских стран-лидеров по разработке и эффективному внедрению национальных программ развития конкурентоспособного судостроения в сложных экономических условиях, сложившихся в отрасли в результате глобального финансово-экономического кризиса. Рассмотрено влияние на неравномерность развития мирового судостроительного рынка так называемых конъюнктурных факторов, отражающих диспропорцию между предложениями судостроительных компаний и спросом судовладельцев на суда различных тоннажей и типов. Показана связь возникновения избыточных мощностей судостроительного производства с несовпадением цикличности рынков судостроения и судоходства. Определены ключевые факторы эффективного развития программ создания конкурентоспособного судостроения с целью их дальнейшего учета при совершенствовании отечественной системы поддержки принятия управленческих решений в сложных экономических условиях.
On the justification of architectural and structural type of research vessel = К обоснованию архитектурно-конструктивного типа научно-исследовательского судна
(2015-11-09) Solomentsev, O. I.; Соломенцев, О. И.; Gofman, A. A.; Гофман, А. А.
The analysis of architectural and structural types of the research vessels (RV) which are built and being built shows that twin hull ships with usual lines and small waterplane area (SWATH) can be used. Therefore, the reduction in the acoustic characteristics of the vessel is rather significant for the RV, since its main task is exploration of fish resources for subsequent work of fishing vessels, as well as for naval supporting research vessels. It is expected that the efficiency indicator is determined by the amount of information obtained as a result of the work of the RV. The method of obtaining the information resides in the RV inspecting the water column or the seabed. At that, the noise of the ship itself affects the operating radius of measuring devices. Thus, the approximate method is suggested. On the basis of it, the specified ultimate noise level for the SWATH can be estimated. The paper suggests the generalized dimensionless indicator of the propeller noise level; it depends on the velocity of the vessel, its draught and the characteristics of the propellers. With displacement being the same, the RV SWATH has significantly better noise level properties, mainly due to the recessed propellers, which makes this option more preferred than that of the RV. = Рассмотрено, при каких требованиях задания на проектирование научно-исследовательского судна будет целесообразным рассмотрение варианта катамарана с малой площадью ватерлинии.
Radiation resistance of metal-glass coatings for floating composite structures = Радиационная стойкость металлостеклянных покрытий для плавучих композитных сооружений
(2015-11-09) Kazimirenko, Yu. A.; Казимиренко, Ю. А.; Shlapatskaya, V. V.; Шлапацкая, В. В.
The article discusses the prospects of application of new metal and glass electric arc coatings made of Sv-08G2C and Sv-AMg5 filled with hollow glass microspheres, powders, liquid silicate and the leaded glass for protection of steel structures from γ-radiation. The purpose of study is to investigate the radiation resistance of metal and glass coatings under γ-radiation Co60. Physical and mechanical properties of the coatings and coated steel samples made of St3 are experimentally studied: microhardness, tensile strength and yield strength. Structural and phase changes are studied using the methods of electronic and optical microscopy, an X-ray analysis. The influence of glass excipients on the stability of the structure and properties of coatings under γ-radiation is noticed. A qualitative comparison of metal-glass coatings to traditionally used lead-containing materials is performed. It is found out that under the influence of γ-radiation of Co60 with the electron energy E = 2.0, 4.5 MeV in electric arc metal-glass coatings there is no structural and phase transitions and the irradiation process is accompanied by surface hardening, coated steel plates made of St3 preserve stable mechanical properties. The study results can be applied for designing the protection against γ-radiation for technical equipment, energy facilities and transport. = Исследовано влияние γ-излучения Со60 на структуру и механические свойства композиционных электродуговых покрытий на основе Св-08Г2С и Св-Амг5, наполненных полыми стеклянными микросферами, порошками натрийсиликатного и свинцовосодержащего стекол. Показаны перспективы применения покрытий в составе конструкций плавучих композитных сооружений для перевозки и хранения радиоактивных веществ низкой и средней активности.

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