Technological processes and material science. Рубрика в журнале - Siberian Aerospace Journal
Approach to optimization of the magnetic circuit of a three-phase induction plant
Статья научная
The article describes an approach to optimization of the electromagnetic regimes of an induction metallurgical plant, designed to mix liquid aluminum under the influence of a running magnetic field. To improve the properties of the molten metal in the furnace, short pole linear magnetohydrodynamic machines with copper windings and a steel core are used. The open configuration of the magnetic circuit and the magnetic coupling between the windings of the inductor lead to asymmetry of the magnetic field. As a rule, a low-frequency transistor inverter is used in the power supply system of metallurgical machines intended to affect non-ferrous metals. Asymmetrical currents in the phases create specific modes of the frequency converter, close to emergency, and a two-phase, three-phase or multi-phase power supply system may become unbalanced. To calculate the integral magnetic fluxes in the toothed zone of an induction installation, it is convenient to apply a multiphase nonlinear model of a magnetic circuit. As a result of the iterative calculation, vector magnetic flux diagrams are obtained and the tractive forces in the melt are estimated. The best conditions for the impact on the melt are obtained with a given objective function when searching for options during optimization of the magnetizing forces of the windings.
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Статья научная
Recent decades have been characterized by increased activity in the use of polymer and composite materials in transport engineering. In this paper, the authors give a generalizing analysis of previously created systems of scientific research and analyze the principles of building automated systems of scientific research (ASSR) that allow solving the problems of determining the parameters of heat exchange, electrophysical parameters and phase transformations in polymer and composite materials when exposed to the HF field. The authors continue the research of the ASSR HF developed by the Irgups team, a number of other scientific schools working in the same direction.therefore, within the framework of the hardware created by these teams, both similar and original developments and solutions are viewed. The analysis of the software parts of the ASSR HF presented by a number of mathematical models and software complexes is given. Thus, the analysis of the structure of the developed systems of scientific research allows us to speak about its dynamic development. The developed and presented flowcharts of automated experiment and automated research systems allow the author to assert that the systems of automated experiment for studying the properties of polymer materials in RF electrothermia created for cer-tain tasks, despite the fact that they were conducted independently and separately, have a single construction methodology. Comparing the results of the research, the author concludes that the construction of a complex system of ASSR HF polar thermoplastic polymers is generally complete
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Change in magnetoresistance in manganese chalcogenides MnSe1-XTeX from bulk to thin-film samples
Статья научная
The electrical and optical properties of anion-substituted antiferromagnetic semiconductors MnSe1-ХTeХ (0.1 ≤ X ≤ 0.4) in the temperature range 77-300 K and magnetic fields up to 13 kOe in bulk samples and in poly-crystalline thin films are investigated. Negative magnetoresistance was found in the MnSe1-XTeX solution in the neighbourhood with a Néel temperature for X = 0.1 and for a composition with X = 0.2 in the paramagnetic re-gion up to 270 K. A correlation was established between the spin-glass state and magnetoresistance for X = 0, 1 and 0.2. The opti-cal absorption spectra were measured in the frequency range 2000 cm-1 < ω < 12000 cm-1. A decrease in the gap in the spectrum of electronic excitations and a several of absorption peaks near the bottom of the conduc-tion band were found. Coexistence of two crystalline phases was found in polycrystalline films of the MnSe1-XTeX system by X-ray diffraction analysis. Resistance maxima were established in the region of polymorphic and magnetic transitions. A model of localized spin-polarized electrons with a localization radius varying in a magnetic field as a result of competition between ferromagnetic and antiferromagnetic interactions is proposed. In the paramagnetic region, negative magnetoresistance is caused by tunneling of spin-polarized electrons during orbital ordering.
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Contact algorithm measurement method for current crystals area grown by Czokhralski method
Статья научная
For crystals grown from the liquid melt according to the Czochralski method when monitoring and controlling the current crystal area based on the contact measurement method, the requirements for improving the accuracy of measuring the crystal area on the cylindrical part of the growth are determined. To eliminate errors due to the accuracy of stabilization of the melt level in the crucible, an algorithm for the operation of the crystal growing unit is proposed which is performed by the programm using the control system. The evaluation time of the control signal on the growing crystal cylindrical part is taken as the sampling time of a given number of crucible movement pulses. The calculation of the control signal starts at the time of the melt level sensor closure, the calculation of the control signal ends at the time of the melt level sensor closure as well, provided that a given number of crucible movement pulses is sampled. The control signal evaluation time in the previous control cycle is used in the current cycle to calculate the melt level sensor closing and opening pause. In the control system at the moment of the contact sensor closure a pause of the closed and the same subsequent pause of the open state of the level sensor is held. During pauses, the status of the contact sensor is not analyzed by the control system and the control of the crucible ascent occurs at a slowed down and accelerated rate of the crucible ascent during “conditionally” closed and “conditionally” open states of the level sensor. The control system is permanently reset at the end of each control cycle. The program control system provides the above algorithm for controlling the process of growing crystals from the liquid melt according to the Czohralski method, at the same time the accuracy of determining the current area of the grown crystal is about 1 %.
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Статья научная
In this paper, we consider the concept of using methods for calculating and designing rocket engine power plants for conversion modeling of local energy in the Arctic and northern regions of the Kras-noyarsk Territory, with an obvious generalization to neighboring administrative formations with similar climatic and structural and logistical conditions. The proposed structure contains power generation units linked to both industrial woodworking waste and natural and industrial thermal tails, identified as sources of low-potential heat, as well as modern low-power reactor plants of block maintenance-free design. The unifying element of power plants is a turbo generator, designed with the use of unconventional, often waste and natural low-grade heat.
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Development of SEM method for analysis of organ-containing objects using inverse opals
Статья научная
The purpose of this study is to test the possibility of using inorganic macroporous structures of inverse opal in sample preparation for scanning electron microscopy of biological objects. As an absorbent substrate we used silica inverse opals prepared by a sol-gel method to study the biological objects. The process of manufacturing the inverse opal involves a complex multi-stage technological process. First, we synthesized submicron spherical particles from polymethylmethacrylate by the method of emulsifier-free emulsion polymerization of methylmethacrylate in an aqueous medium in the presence of a diazoinitiator. This method can be used to obtain an ensemble of particles with high monodispersity, the average size of which can vary in the range from 100 to 500 nm. Then, by self-assembly technique, we deposited the beads of polymethylmethacrylate into ordered matrices (templates), mainly with a face-centered cubic lattice. The resulting mesoporous structures, called artificial opals or colloidal crystals, had lateral dimensions of about 10 × 10 × 2 mm. Then we heat-treated the opals to 120 °C to harden the template before being impregnated with the precursor. Further, we impregnated the opals with silica sol with a particle size distribution from 1 to 5 nm, obtained by hydrolysis of tetraethoxysilane in the presence of hydrochloric acid, and then, after curing and drying the impregnating composition in air at room temperature, we multi-stage fired them up to 550 °C at normal pressure in the air atmosphere to remove all organic components. As a result, the macroporous metamaterial (the so-called inverse opals) with an open system of pores up to 400 nm in size, occupying about 80 % of the volume, were obtained. We studied lactic acid bacteria of cucumber brine and human red blood cells with TM4000 Plus, SU3500 and S-5500 scanning electron microscopes. Auxiliary substance for the sample preparation was ionic liquid VetexQ EM (Interlab LLC). We showed that it is possible to use the inverse opal as an absorbent substrate for sample preparation and rapid analysis in scanning electron microscopy without pre-drying, chemical treatment, or temperature exposure. To improve imaging in the electron microscope, we used sputter coater to cover the inverse opal surface with a thin film of platinum. The use of ionic liquid in combination with the absorbent porous medium allows preserving an original shape of the biological structures. Using the human red blood cells and lactic acid bacteria, we showed that it is possible to carry out of the morphological analysis of the cells using various scanning electron microscopes. We found that on the basis of the inverse opal, there is a fundamental possibility of creating the absorbent substrate suitable for repeated use in the study of the biological objects. At the same time, trace remnants of previous samples remaining after annealing the plate do not introduce significant distortions when conducting new series of observations. In this study, we obtained high-quality electronic micrographs of the biological objects with high resolution and contrast. At the same time, due to the use of the inverse opals as the absorbent substrate, time and financial costs for research are reduced.
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Статья научная
Aluminum-based alloys are widely used in many branches of modern industry (aviation, mechanical engineering, shipbuilding, instrument-making, energy and medicine, etc.). The promising method for further expanding the scope of these alloys is surface treatment based on the use of concentrated energy fluxes (laser beams, plasma flows, powerful ion beams, continuous and pulsed electron beams). The purpose of this paper is to establish the possibilities of integrated electron-ion-plasma modification of the structure and properties of the surface layer of technically pure aluminum A7. The surface alloy was formed in a single vacuum cycle using the “KOMPLEX” facility (ISE SB RAS) by spraying a titanium film with a thickness of 0.5 μm and the subsequent irradiation with an intense pulsed electron beam in the aluminum melting mode. After 20 “spraying/irradiation” cycles, nitriding (540 °C, 8 h) of the formed surface alloy was performed in a low-pressure gas discharge plasma using the plasma generator “PINK”. Surface alloy studies were carried out applying the modern materials science methods (scanning and transmission electron diffraction microscopy, X-ray phase analysis, determination of hardness and wear resistance). The choice of elements alloying the surface layer of aluminum was based on the analysis of binary state diagrams of Al-N, Al-Ti, Ti-N systems and the isotermal section of the ternary system Al-Ti-N. It has been shown that formation of an entire series of binary and ternary compounds, including MAX-phases of the composition Ti2AlN and Ti4AlN3, is observed under equilibrium conditions in the Al-Ti-N system. The carried out research has allowed to state that an integrated method of electron-ion-plasma modification of technically pure A7 aluminum by nitriding (540 °C, 8 h) of the surface alloy formed by pulsed melting in vacuum of the Al-Ti system (20 “spraying/irradiation” cycles with an electron beam with parameters 10 J/cm2; 50 μs; 10 pulses; the titanium film thickness in each cycle 0.5 μm) leads to formation of a multiphase multielement submicro-nanocrystalline surface layer up to 20 μm thick. It is shown that the mechanical (microhardness) and tribological (wear resistance and friction coefficient) properties of the formed surface layer exceed manifold the properties of the original commercially pure aluminum A7.
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Effect of electron-phonon interaction on transport properties in TmxMn1-xS
Статья научная
In solid solutions TmxMn1-xS, based on measurements of IR spectra and thermal expansion coefficient in the temperature range 80–500 K, the temperatures of sample deformation and disappearance of the absorption intensity of IR spectra at some frequencies are established. Anomalies in the temperature behavior of the electrical resistance are found, the sign of the current carriers and the mobility are determined from the Hall coefficient. The correlation between the temperatures of coefficient of electrical resistance and lattice deformation has been determined. A model of lattice polarons is proposed. The spectrum of electronic excitations and the density of electronic states in the interaction of electrons with flexural and tensile modes of the octahedron are calculated in the random phase approximation.
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Статья научная
Cation-substituted solid solutions YbXMn1-XS were prepared by the melt method from polycrystalline sulfide powders. The synthesized samples are antiferromagnetic semiconductors and, according to the results of X-ray structural analysis, have an FCC structure of the NaCl type. Structural, electrical, optical, and acoustic properties of the chalcogenide system YbXMn1-XS were studied in the temperature range 80–500 K. The effect of variable valence elements on the electronic structure of cationic substitution of manganese sulfide has been studied. The change in the electronic structure in the YbXMn1-XS system occurs due to the electron-phonon interaction. Samples with variable valence have anomalous compressibility, which is confirmed by the data on the thermal expansion coefficient and the change in the attenuation coefficient. As a result of inelastic interaction with d- electrons, the density of states at the Fermi level changes, this is reflected in the temperature dependence of the conductivity. The positions of the f-level and two electronic transitions were determined from the IR spectra. A zone of temperatures and concentrations was found, where a correlation of structural, electrical, optical and acoustic properties is observed. To explain the experimental results, the electronic structure of the semiconductor is considered and a model is proposed that qualitatively describes the experiment.
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Electrooptical response of the films of polymer dispersed nematic with conical boundary conditions
Статья научная
The electrooptic response of films of polymer dispersed nematic under conical boundary conditions has been investigated. An axial-bipolar director configuration is formed in nematic droplets. It has been shown that initially, the orientation of droplet’s bipolar axes is chaotic both in the sample plane and relative to the normal to the substrates. The applied voltage U orients the droplet’s bipolar axes parallel to the electric field and the reorientation process is threshold only when the bipolar axis is initially orthogonal to the substrate normal. Accordingly, the samples strongly scatter light in the initial state, and the optical response to an electric field is thresholdless. The samples with a film thickness of 5, 10, 20 and 30 μm have been studied. All the samples under study are characterized by a high transmittance and contrast ratio, which for a 30 μm sample are equal to 84 % and 5536, respectively, and achieved at U = 12 V. The results obtained are relevant for use in low-power optoelectronic devices required for the development of energy-saving technologies in aerospace engineering.
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Factor analysis of inelastic electron scattering cross section spectra of iron monosilicide FeSi
Статья научная
The inelastic electron scattering cross-section spectra of FeSi silicide were calculated from the experimental reflected electron energy loss spectra as the product of the average inelastic mean free path and the differential cross section of the inelastic electron scattering. To inelastic electron scattering cross-section spectra study, factor analysis was used. This method allowed us to quantitatively separate the surface and bulk contributions to the spectra, and determine the energy of the bulk plasmon more accurately than it is possible using traditional methods. Inelastic electron scattering cross-section spectra (Kλ-spectra) are the products of the average inelastic mean free path λ and the differential inelastic scattering cross-section K (E0, E0 – E), where E0 and E are the energies of the primary and reflected electrons, respectively. The advantage of inelastic electron scattering cross section spectroscopy is that, unlike the reflected electron energy loss spectra, the Kλ-spectra exclude losses due to multiple excitations, and the intensities are determined in absolute units. These spectra are also more sensitive to changes in the energy of the primary electrons and the angle of emission. Inelastic electron scattering cross-section spectroscopy allows to determine the element composition with much greater accuracy than the traditional method of reflected electron energy loss spectroscopy. In this work, factor analysis is used to study the inelastic electron scattering cross section spectra of the FeSi silicide. This method allowed to solve the actual problem of separating spectra into contributions of a different origin, quantify them and determine the energies of a bulk plasmon more accurately compared with traditional methods. The study of electron energy loss processes by isolating contributions of different origin in the inelastic electron scattering cross section spectra is one of the urgent problems of electron spectroscopy, which can be used to assess the effect of surface excitations in REELS, XPS and AES.
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Features of electroactivated water production at a coaxial electrode location
Статья научная
Important characteristics of any product are quality and reliability. One of the factors affecting product reliability is the surface cleanliness provided by flushing with liquids. Electroactivated water and aqueous solutions can be used as liquids. On the basis of domestic and foreign experience, leading experts have developed methodological instructions for the widespread implementation of electro-activated water and aqueous solutions in instrument-making and mechanical engineering. For the production of electrochemically activated water and solutions, non-flowing and flowthrough modular elements, as well as universal installations, have been developed. Analysis of the structures of these devices has shown that flat metal plates are used as electrodes, therefore there are volumes of water that are subjected to uneven electrical effects. As a result, the specific energy consumption for obtaining activated water is significant. The purpose of the work is to reduce the specific energy consumption in the production of activated water and aqueous solutions. Coaxial arrangement of the electrodes leads to reduction in energy consumption. The study of the electroactivator of water with a coaxial arrangement of electrodes allowed us to establish the optimal ratio between the volumes of anolyte and catholyte and the time of electrolysis of water and an aqueous solution of sodium chloride. A new indicator of efficiency (the specific energy consumption per unit of change in the pH of water or an aqueous solution) objectively reflects the perfection of the design of electroactivators. The research results can be used in instrument and mechanical engineering.
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Features of modeling the electron beam distribution energy for the electron-beam welding process
Статья научная
The energy distribution of the electron beam by means of application of various scanning paths, affects for-mation of the weld, which relates to the quality of the welded joints. Experimental studies, conducted by the au-thors of the article showed that scanning the electron beam in the form of a raster shape gives the best quality of welded joints; therefore, the trajectories of a classical raster and a truncated raster are proposed for the elec-tron beam welding process. When conducting research in this direction, the authors discovered the following regularity: with an increase in the scanning amplitude along the junction, the vapour-gas penetration channel transforms into a stable cavity, along the front wall of which the metal melts, and along the side walls it is trans-ferred to the tail of the weld pool. The discovered effect of the formation of a penetration cavity is to be investigated in electron beam welding of various materials and thicknesses. For this the necessary equipment is to be created, allowing to make scan-ning in the form of various rasters. To improve the quality of the electron beam welding process, trajectories of a classical raster and a truncated raster across the joint are proposed. For these scanning trajectories, analytical expressions and families of calculated characteristics of the electron beam energy density distribution over the heating spot are obtained. Modulation of the electron beam oscillation in the form of a truncated raster across the junction makes it possible to obtain a two-humped distribution of the beam energy on the surface of the part along the heating spot. The obtained characteristics allow a more meaningful approach to optimizing the pro-cess of electron beam welding of various materials.
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![Formation features of the central layers of the alloy Fe – 3 % Si (110)[hkl] rolling textures](/file/thumb/148321699/formation-features-of-the-central-layers-of-the-alloy-fe-3-si-110-hkl.png "Formation features of the central layers of the alloy Fe – 3 % Si (110)[hkl] rolling textures")
Formation features of the central layers of the alloy Fe – 3 % Si (110)[hkl] rolling textures
Статья научная
The fields of solid-state physics, metallurgy, plastic deformation, mathematics and continuum mechanics are engaged in the studies of texturing of metals and alloys and their influence on the operational properties of products. As a rule, the most significant results are expected at the interface between these sciences. The technologies of obtaining textured materials by metal forming processes occupy a special place in the metalworking sphere. This is due to promising directions in technologies for producing semi-finished and final products with improved structure-sensitive properties, by regulating the texturing, taking into account initial crystallographic orientation of the workpiece. The first issue to note is the formation of an ideal, one-component crystallographic texture in anisotropic metallic materials. The second issue is to obtain semi-finished and final products with more specific service properties: crystallographic texture with specific predetermined components. For instance, due to the crystallographic texture, it is possible to increase the resistance of metals and alloys against corrosion and hostile environment. Considering textured materials as composite, we must note that directionally oriented crystallites with crystallographic directions relative to the laboratory direction perform as reinforced elements. The initial texture in the processing plane is especially important. The materials, which possess unique structure-sensitive properties acquired through pressure treatment, are very promising for a widespread use in the sphere of aerospace technology. Obviously, the properties and means of their achievement are diverse and require setting a specific task. Therefore, further research in this sphere is especially promising. The article presents the research findings, considering the effect of initial crystallographic orientation and deformation modes on the rolling texture in the central layer of Fe – 3% Si (110)[hkl] single crystals. Several groups of single crystal samples underwent rolling under laboratory conditions. The groups of samples were classified according to the final deformation rate, the ideal crystallographic orientation of the rolling plane and deflections of the ideal orientation plane direction from the rolling direction. The methodology of the experiment took into account the compression rate value during one rolling. We analyzed the results of rolling, using the radiographic method. The next step was to superimpose the radiographic data on a stereographic projection and to construct straight pole figures. The results of straight pole figures decoding revealed differences in the texture formation from the previously obtained data. The research shows the manifestation of the one-component deformation texture in the central layer.
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Honeycomb fillers manufacturing technology from polymeric composite materals
Статья научная
The honeycomb filler is an integral part of the spacecraft's sandwich panel. Currently, a honeycomb filler made of aluminum alloys is used. The proposed technology makes it possible to replace the honeycomb filler material from aluminum alloys with polymer composite materials (PCM). The main difference between the developed technology for the production of honeycomb filler by the RTM method is that corrugated tape is glued during the formation of the composite material. This is a separate process in the existing methods for the production of honeycomb cores from PCM. This paper presents the results of creating a prototype of a honeycomb filler by the RTM-method, a technological process has been developed.
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Influence of a constant electric field on the adsorption purification of water from iron ions
Статья научная
Using electrochemical action (ECA) to treat water was first proposed in UK in 1889. At present, many methods of ECA are known (electro flotation, electro coagulation, electro osmosis, electrophoresis, etc.). In the production of rocket and space technology, galvanic technologies are used, as a result of which waste water is contaminated with metal ions. Known methods of wastewater treatment do not allow to ensure the maximum permissible concentration of metal ions in treated water, or are expensive or difficult to operate in industry. Iron ions are among the most polluting components of wastewater of most industries. So increased control and the development of effective methods of wastewater treatment are necessary. Iron affects the intensity of phytoplankton development and the qualitative composition of microflora in reservoirs. The toxicity of iron compounds in water depends on the hydrogen index of water. The alkaline environment dramatically increases the risk of fish poisoning, as in such conditions, iron hydroxides are formed, which are deposited on the gills, clog and corrode them. In addition, iron compounds bind oxygen dissolved in water, which leads to the mass death of fish and other hydrobionts. The article presents the method of conducting experiments, the methods of sorption, electrochemical and combined water treatment, including electrochemical action and adsorption. The results of studies of these methods of water purification from iron ions are presented. The dependence of the degree of purification on the electric field strength, interelectrode distance and water treatment time is revealed. With an electric field strength of 5.16 V/mm, a temperature of 20–22 °C using quartz sand as an adsorbent and a processing time of 1 minute, the concentration of iron ions decreased from 2.5 to 0.25 mg/l (at MPC = 0.3 mg/l). The proposed combined cleaning method requires inexpensive and affordable materials and is easy to operate.
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Influence of the magnetic field on transport properties of holmium – manganese sulfide
Статья научная
Holmium-manganese sulfide with giant magnetoresistance refers to new magnetic sulfide compounds of holmium and manganese that have the effect of giant magnetoresistance (i. e., with special magnetoelectric properties), which can be used as components of sensor technology, magnetic memory, and spintronics. The technology of manufacturing polycrystals HoXMn1-XS grown by crystallization from the melt of the obtained powdered sulfides with a purity not lower than 99,9 %, in glass-carbon crucibles and a quartz reactor in an argon atmosphere is presented. According to the results of x-ray diffraction analysis, HoXMn1-XS holmium-manganese sulfides have a HCC structure of the NaCl type. As the degree of cationic substitution increases, the unit cell parameter increases linearly with the concentration. No concomitant impurity phases are detected in the synthesized samples. To determine the state of the spin glass, magnetic moment measurements are conducted at several frequencies ω = 1 kHz, 10 kHz and 100 kHz. The dependence of magnetic characteristics on the frequency of measurements is found. The damping of the magnetic moment and its increase with a decrease in temperature is reviled, which is connected with the formation of metastable States. Measurements of electrical resistance without a field and in a magnetic field are conducted. Anomalies in the temperature dependence of the conductivity are found. A change in the magnetoresistance sign is detected with the increase of temperature below and above room temperature.
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Interaction of magnetic and dielectric subsystes in a bismuth nodymic ferrite-granate
Статья научная
Bismuth-substituted ferrite garnets possess magneto-optical (MO) properties and are used as spatial light modulators and indicators. The paper studies the influence of magnetic and electric fields on the structural characteristics of thin epitaxial films of bismuth-neodymium ferrite garnet (Bi: NIG) deposited on glass and gallium gadolinium garnet (GGG) substrates. Dynamic properties of polarization, relaxation in a magnetic and electric field are considered, which is an important task for getting a deep insight into the mechanisms of electromagnetic phenomena in solids. Dependence of the magnetostriction coefficient on the magnetic field and dependence of a relative change in the length of the film on the electric field at different temperatures are obtained. A change in the sign of magnetostriction constants with respect to temperature was found. The electric polarization in a periodically applied electric field of 400 V / cm with a frequency of 10 MHz is determined for various magnetic field orientations of 12 kOe and in the absence of a magnetic field. Anisotropy of polarization in a magnetic field and a functional dependence of the polarization relaxation on time are found. These materials can be used as sensors of the magnetic field in a spacecraft.
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Laboratory separator of bulk materials
Статья научная
New materials for spacecraft radiation screens engineering require a fine classification of powder materials by particle size. The article concerns the construction of powder materials laboratory separator. This type of material separation is related to gravity methods. The Moseley laboratory separator serves as the prototype of the construction with table longitudinal shaking and diametrical vibrations by means of buffers during the separation process. The unbalanced oscillator yields deck separation surface harmonic vibrations in all directions. The unbalanced oscillator DC motor voltage control gradually alters the vibration frequency and supports finer separation of the material. A power pipe enables to conduct perpetual separation process. In prototype, in contrast, up to 100 g weight is processed for up to 5 minutes. To improve the materials fine and small classes separation efficiency, riffles are made on the separation surface, which determine the places of concentration of material particles. As a result of the conducted researches for elimination of the secondary circulation flows, a system of diametrical reefing is worked out: the riffle is approximately equal to the maximum particle size of the separated material and is equal to 0.2 mm in this construction; the distance between riffles is equal to 50 mm, the tilt angle is 80 degrees relative to the deck longitudinal side. The particle motion depends on the inclination angle of the separation surface. Large particles move upwards at angles of up to 5 degrees, and downwards at angles higher than 5 degrees. Vibration frequency and amplitude alteration, as well as adjusting the inclination angle of separation surface enables to move and adjust the speed of different properties and sizes of test material. The laboratory separator work is based on the physical effects, which enable to vary the location of the power pipe. This fact allows the construction to be adapted to a variety of specific conditions and expands the construction sphere. The separator construction is simple for production and operation, and can be quickly reconfigured if necessary. The separator portability allows it to be transported.
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Статья научная
Operational characteristics of contacting elements of cars and mechanisms are by far defined by a layer quality indicators at the surfaces of contact. One of the ways of increasing details durability, including missile and space equipment details, is the superficial plastic deformation (SPD). In the article aspects of dynamic ways of hardening from the position of the wave theory of blow are considered. The construction of a shock stand on the basis of a linear electrodynamic drive with a size of 60 mm, operating in a shock-pulse mode, as well as a well-known mathematical model of the workflow – the movement of the armature with the tool at the moment of striking the surface. This model does not fully describe the operation process since the mass of the striker taken into account equaled 1 kg, which does not characterize the process of the impact tool, the purpose of which is the object deformation (for example, work hardening with the aim of surface material sealing or breakdown of the hole in it, or applying license plates markers). The mathematical model that describes the movement of the armature with the tool, taking into account the elastic deformation of the hardened surface was obtained. In the course of the performed calculation, the magnitude of the elastic deformation of the hardened surface was calculated from the dynamic component of the force impulse applied to it through the indenter (the tip of the impact tool). The layout of the shock stand with the equipment used, are offered. Experiments on the signal recording with various arrangements of piezoelectric transducers on the anvil – the hardened surface (diagrams of the sensors location are given) were carried out.
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