DEPENDENCE OF QUALITATIVE AND QUANTITATIVE INDICATORS OF ORE RESERVES ON THE MAXIMUM PERMISSIBLE INTERVAL OF UNCONDITIONAL ORES OF THE SOTK GOLD ORE DEPOSIT

At the Sotk gold ore deposit, the following morphological types of ore bodies can be distinguished: vein zones; veins and vein-like bodies; mineralized dykes and a vein zone in gabbro - massifs. The deposit is characterized by rather difficult mining and technical conditions. The enclosing rocks of the near-ore bodies have undergone intense hydrothermal changes at a distance of 5,0...10,0 m to 50,0 m, as a result of which, within the boundaries of these zones, the enclosing rocks have lost their strength and stability. The stability of the host rocks is also greatly influenced by postore tectonic faults, which are widespread in the field. The ore is also volatile. The strength factor of ore and host rocks varies from 3 to 20, with a predominance of 8...13. Hydrothermally altered metasomatites, which make up the mineralized zones, are prone to caking. The ore loosening factor is 1,25...1,40. The average bulk density of ore is 2,6 t / m3, and the bulk density of the host rocks is 2,3... 3,2 t / m3. At the deposit, conditioned and substandard intervals alternate with each other and there is no clearly expressed regularity of their spatial location, which predetermines the use of the ore-bearing factor when calculating ore reserves. The ore content ratio is determined by the ratio of the amount of conditioned ores to the total amount of ore mass, and the amount of conditioned ores is determined using the condition parameter “maximum - allowable range of substandard ores or waste rocks” included in the reserve calculation. For the Sotk gold ore deposit, the regularities of changes in ore reserves in the subsoil, the gold content in the ore massif and the ore content factor from the “maximum allowable to an increase in ore reserves in the subsoil and the ore content ratio with a decrease in the gold content in the ore massif and vice versa are revealed.

ИЗУЧЕНИЕ МЕХАНИЗМА И КИНЕТИКИ ВОССТАНОВЛЕНИЯ КОНЦЕНТРАТОВ ГЕМАТИТА С УГЛЕРОДОМ И КАРБОНАТОМ НАТРИЯ

Теоретическими расчетами обоснованы и экспериментальным методом доказаны механизм и кинетика восстановления гематитовых концентратов углеродом и карбонатом натрия. Согласно описанному механизму, в присутствии 10% соды резко ускоряется процесс восстановления, а углерод является лучшим восстановителем для гематитового концентрата. Показано, что сода активирует процесс газификации углерода продуктами деления (Na2CO3→Na2O+CO2), которые сохраняют избыточную энергию и вводятся в кристаллическую решетку графита, помогая ослабить связи между базовыми плоскостями. Сода также влияет на извлечение магнетита, на поверхности которых адсорбируются возбужденные молекулы Na2O. В этом случае добавление соды к одновалентному металлу способствует изменению количества свободных электронов или дырок, в результате чего изменяются также реакционные свойства оксида. Выявлено, что при температуре 500 °C практически не происходит взаимодействия карбоната натрия с оксидом железа, а при температуре 700 °C реакция оксида железа с содой протекает очень интенсивно, в результате чего образуется феррит натрия. Однако в восстановительной среде при температуре 500...600 °C оксиды железа восстанавливаются до низших оксидов, а при более высокой температуре - до металлического железа. Процесс обжига изучен методом дериватографического анализа, в результате которого были выбраны следующие оптимальные режимы обжига: Tо=1000…1050 0C, τо= 2,5…3,0 ч. Установлено, что роль соды заключается не только в интенсификации образования и восстановления силиката, но и в уменьшении производительности процесса на 20% и снижении температуры восстановления на 130…150 °C. Показано, что твердофазные реакции образования силикатов в восстановленной смеси при температуре 700…1100 °C приводят к образованию водорастворимых соединений, которые легко удаляются влажной магнитной сепарацией.

ИССЛЕДОВАНИЕ ПОЛЕЙ ДЕФОРМАЦИЙ В ЗЕРКАЛЬНОМ КРИСТАЛЛЕ РЕНТГЕНОВСКОГО ИНТЕРФЕРОМЕТРА, ПОДВЕРГНУТОГО ИОННОЙ ИМПЛАНТАЦИИ

Обзор научной литературы по теории интерференции рентгеновских лучей показывает, что вопросам изучения тонких имплантированных слоев рентгенодифракционными методами посвящено много работ. Все эти работы имеют некоторые общие характерные черты. В частности, все рентгенотопографические исследования проводились с образцами, которые облучались энергиями выше 1 МэВ. При облучении ионами с низкими энергиями, в особенности в малых дозах, необходимо пользоваться рентгеноинтерферометрическими методами, чувствительность и разрешение которых несравнимо велики. В настоящей работе приведены результаты теоретических и экспериментальных рентгеноинтерферометрических исследований несовершенств кристаллов, возникающих в результате ионной имплантации малыми дозами и низкими энергиями. Результаты исследований представлены с помощью рентгенодифракционных муаровых картин полей деформаций, возникающих в одной из работающих частей зеркального блока трехкристального рентгеновского кремниевого интерферометра, подвергнутого ионной имплантации, в зависимости от дозы облучения. Исследовано также перераспределение напряжений, возникающих в этом участке блока интерферометра при его бомбардировке. Полученные результаты дают основу для решения обратной задачи, а именно - задачи восстановления полей механических напряжений в кристаллических блоках интерферометра путем расшифровки муаровых картин, так как изменение муаровых картин будет заключать в себе информацию о механических напряжениях. Таким образом, метод рентгеноинтерферометрического муара дает возможность прямого экспериментального изучения полей механических напряжений, созданных структурными дефектами кристаллической решетки. Выведено условие применимости выражения для определения периода муаровых картин при оценке внутрикристальных деформаций.

STUDYING THE PHYSICAL CHARACTERISTICS OF THE SPATIAL GRID OF STRUCTURED STYRENE-BUTADIENE POLYMERS FOR ORTHOPAEDIC INSOLES

Structuring reactions of polymer materials should be attributed to intermolecular reactions.The process of structuring is accompanied by a modification of the backbone polymer macromolecules both by the addition of fragments of cross-linking agent and through the development process of isomerization and cyclization of the macromolecules of polymers under the action of cross-linking agents or their transformation products. The process of formation of cross-linked structures of hydrocarbon polymers is a complex and multistage chemical reaction. The formation of cross-linked structures of hydrocarbon polymers, such as SCS-30 and SKS-50 with a latent curing agent LR-3 is considered. The results of studies of the effect of the latent curing agent LR-3 and sulfur vulcanizing groups on the physical parameters of the spatial grid of the structured styrene-butadiene rubbers are given. It is experimentally proved that new spatially cross-linked styrene-butadiene-based elastomers based on the latent hardener-3 possess all the properties inherent to the polymer mesh. The most significant features include its ability to undergo large reversible deformations, which is important for orthopaedic insoles. It is experimentally proven that the density of spatially structured grids for different compositions is as follows: for the polymer compositions based on rubber SKS-30 with a latent curing agent LR-3 is 1,26•1027 sm-3; for a composition based on the SCS-50 rubber with a latent curing agent LR-3 is equal to 1,29•1027 sm-3. The density of sulfur vulcanizates: 2,17•1031 sm-3 and 2,17•1031 sm-3 respectively for the polymer compositions SKS-30 and SKS-50. On the basis of experimental data, it is establisbed that the most promising material as orthopaedic insoles is the polymer composition based on styrene -butadiene rubber SKS-30 with a latent curing agent LR-3.

INVESTIGATING THE PROCESS OF STRUCTURE FORMATION AND WEAR RESISTANCE OF ABRASIVE TOOLS ON THE METAL BOND OF COMPOSITION 51%Fe+9%Ni 32%Cu+8%Sn MADE OF METALLIZED BY TITANIUM DIAMOND POWDERS

The process of of structure formation and wear resistance of abrasive tools on the metal bond of composition 51%Fe+9%Ni+32%Cu+8%Sn made from metallized by titanium diamond powders is investigated. The metallographical substantiation is introduced, as well as the wear-resistance and the working capability of abrasive tools are studied. It is shown that the structure is heterophase and consists of five phases, the first of which is a solid solution based on nickel, the second is a solid solution of tin, nickel, and iron in copper, the third is a solid solution of nickel, copper and tin in iron, the fourth and the fifth are intermetallic compounds with a defective structure. It is revealed that in the developed composite material, the volume content of heavy components is approximately 63%, the plastic component occupies approximately 25% of the sample volume, and the intermetallic phases - approximately 12% of the total volume, which are distributed over the entire sample surface. Based on the results of the complex investigation of the operability and wear resistance of diamond tools manufactured according to the developed technology carried out in the laboratory and production conditions for processing non-metallic materials, the optimal modes of manufacturing highly productive and wear-resistant diamond-metal abrasive tools were selected and substantiated: cold pressing pressure P = 600 MPa, free sintering temperature: T = 850°C, holding at this temperature: τ = 45 min. Applying the developed technology as a method for producing a diamond tool ensures the high efficiency of production.

INVESTIGATING THE IMPACT OF AN EXTERNAL INFLUENCE ON THE DYNAMIC BEHAVIOR OF DISLOCATIONS IN SILICON CRYSTALS

The results of studying of the influence of a constant magnetic field on the dynamic behavior of dislocations in the crystalline block of an interferometer subsequently subjected to uniaxial mechanical tensile stress along the crystallographic axis of silicon are presented. The periodicity of the dilatation moire image after these influences, the average means free path of a dislocation in a crystal (block), the amount of slip, the average density of dislocations along the slip line, the relative deformation, and Young's modulus are calculated. To study the effect of a stable magnetic field on the dynamic behavior of dislocations in silicon crystals, a special three-block X-ray interferometer was fabricated in one of the blocks, and dislocations were introduced using the technique proposed by us. The experiments were carried out for various values of the magnetic field induction and mechanical stress. It is shown that the sequential action of these external influences leads to an increase in the starting stress, a decrease in the velocity of dislocation movement, a delay in the onset of dislocation movement, and the appearance of a hardening phenomenon. Experiments show that the displacement mobility characteristics are especially sensitive when the modulus of the magnetic induction vector reaches a certain threshold value for a given sample. It was shown that, in a sample containing silicon dislocations, the magnetic memory that appears after storage in a magnetic field is short-lived. It is found that the speed of movement of a dislocation in a magnetic field processed by a magnetic field, "then" subjected to mechanical stress (stretching), changes, but in practice the energy of its activation does not change. A theoretical analysis of the above experimental results is carried out, their scientific substantiation is given, all the factors associated with the phenomena observed in experiments are revealed.

СПОСОБ ГЕОТЕХНИЧЕСКОГО МОНИТОРИНГА ПОРОД ТАШТУНСКОГО РАЗЛОМА ЮГО-ЗАПАДНОГО БОРТА КАДЖАРАНСКОГО КАРЬЕРА

A method has been suggested for geotechnical monitoring of tectonic fault rock mass of the south-west wall in Qajaran open-pit mine by applying the pseudo-static method of CPTu (Cone Penetration Test with in-situ pore water pressure measurements) which gives an opportunity to define the root parameters of soils such as: pore water pressure, unit weight, drained and undrained shear strength. The versatile in-situ CPTu methods allow to profile simultaneously the geotechnical properties of each soil strata with permanent penetrating speed, and also while using the SCPTu (Seismic Cone Penetration Test with in-situ pore water pressure measurements) method, as well as determine horizontal and shear seismic wave velocities from the given geomechanical environment. At that, it also becomes possible to pull out independently intact samples from tectonic-fault-soils for future laboratory testing. Two different approaches for geomechanical proposition of the south-west wall stability of Qajaran open-pit mine based on the limit equilibrium theory and outputs from the proposed in-situ geotechnical seismic monitoring (SCPTu) have been analysed. The difference of the results from the two analyzed approaches (USA vs ESA) was about 8 to 10% in estimating the slope stability. Based on the analyzed results of the stability of the south-west wall of Qajaran open-pit mine, it is recommended to apply undrained strength analysis for undrained tectonic-fault soils (USA – Undrained Strength Analysis) instead of the effective drained strength analysis (ESA – Effective Strength Analysis) for drained rocks by taking into account the developed excess pore water pressure when saturated clayey soils sheared in undrained conditions.

ПОЛУЧЕНИЕ КОМПОЗИТА НА ОСНОВЕ КАРБОСИЛИЦИДА ТИТАНА И ИССЛЕДОВАНИЕ ЕГО ЭЛЕКТРОПРОВОДЯЩИХ СВОЙСТВ

Обсуждаются вопросы получения нового класса мультифункциональных композитов путем высокотемпературного самораспространяющегося синтеза (СВС) различных металлических порошков. Изучаются их свойства. К классу таких композитов относятся МАХ-фазы. В результате предварительных экспериментов выявлено, что из смеси порошков титана, алюминия и сажи методом СВС можно получить порошковый композит, в котором максимальный выход основной МАХ-фазы Ti3AlC2 составляет 82,5%. По данным рентгенофазового анализа (Powder Cell), при СВС методе переработки образца FeSi+3Ti+2C (FeSi (30%) количество карбида титана в полученном продукте составляет 12,5%. Это обусловлено тем, что при синтезе выделяющееся тепло недостаточно большое и конечный продукт не успевает сформироваться до конца. Для приведения продукта к равновесному состоянию был осуществлен дополнительный отжиг при температуре Т=1250ºС (3 ч). Поскольку в конечном продукте присутствует карбид титана, то предполагалось, что небольшие добавки TiSi2 увеличат содержание карбосилицида титана в спеченном композите за счет взаимодействия карбида с силицидом титана. Поэтому также был проведен отжиг при температуре Т=1650ºС, но с добавкой к конечному продукту 5 мас.% TiSi2. Отжиг продукта СВС и добавка 5% TiSi2 к конечному продукту приводят к увеличению содержания Ti3SiC2 до 100% с минимальным количеством карбида титана (следы). Полученный однофазный материал на основе карбосилицида титана обеспечивает электропроводимость композиционных покрытий при температурах выше 300˚С. Результаты опыта подтверждены микрорентгеноструктурным анализом.

MODERN AIRCRAFT MATERIALS

The modern world with its realities dictates more stringent requirements for mechanical engineering products, based on mutually beneficial scientific and technical cooperation, new innovative technologies for the production and processing of parts, 52 technological modernization and increasing production efficiency, environmental safety, as well as in order to improve the technical and operational characteristics and competitiveness of the manufactured products. However the process of mastering new innovative technologies for the production and processing of parts is often very slow due to both objective and subjective factors. It is important to note that the domestic engineering industry is mainly focused on the purchase of imported equipment and tools and very rarely on the introduction of new high-tech processes. In recent years, the development of mechanical engineering technology, along with the already traditional requirements set to the production of parts and components, is increasingly putting forward the condition for the environmental friendliness of their manufacture. The aviation industry, for landlocked countries with limited capabilities, is one of the foundations for ensuring the country's defense capability and exporting high-tech and expensive products. In this regard, it is of particular importance to improve the technical and operational characteristics and indicators, the quality of aviation products through the use of modern metallic and non-metallic materials, the development and implementation of new highly efficient and environmentally friendly technologies for their production and processing with relatively small capital investments. It should be noted that in recent years, thin-walled parts for various purposes have been widely used in the design of aircraft, and the use of new highly efficient technologies to improve their technical and operational characteristics is of great practical importance.

ПОВЫШЕНИЕ КОРРОЗИОННОЙ СТОЙКОСТИ ДЕТАЛЕЙ КУЗОВА МИКРОАВТОБУСОВ СЕМЕЙСТВА “ГАЗЕЛЬ”

The automotive industry makes a significant contribution to the global economic production. Its annual turnover is comparable to the sixth largest economy in the world. The automotive industry accounts for about 5% of the world Gross Domestic Product (GDP). The automotive industry has a powerful multiplier effect and stimulates the development of a number of other industries. Automotive products account for about half of the world's oil consumption, half of the rubber produced, 25% of glass and about 15% of steel. Note that the size and structure of the automotive market often act as indicators of the level of economic development, and its state quickly and accurately reflects the changes taking place in the world economy.0 The average service life of a car is up to 15-20 years, depending on many factors. The service life is significantly reduced when the car is exposed to aggressive operating conditions. Most often, the car fails due to corrosion damage (corrosion) of its parts: the body, pipelines, elements of brake systems, frames and other important components. The damage caused to humanity by corrosion is enormous. According to various sources, corrosion "eats" from 10 to 25% of the world's iron production. As a result of corrosion of the load-bearing and critical elements of the rolling stock of road transport, reliability and performance, passive safety and road safety are sharply reduced, which requires the use of new effective means and methods to increase the corrosion resistance of critical parts and components of the car. One of the effective solutions to improve the anti - corrosion properties is the application of an insulating coating on the surface of the metal, which can significantly reduce the rate of its corrosion. However, it is necessary to take into account the economic component and the complexity of the technological process. For minibuses of the “GAZEL” family operated in Yerevan, it is of particular importance to increase the corrosion resistance of parts and load-bearing elements of the body.