Nanostructuring of the surface layer by the method of electric-spark alloying

2020 ◽  
pp. 113-121 ◽  
Author(s):  
Elizaveta Yu. Kudryashova ◽  
Ivan A. Shamberov ◽  
Roman N. Zadoroznyy
Keyword(s):  
Mechanical Properties ◽  
Surface Layer ◽  
Base Material ◽  
Surface Profile ◽  
Carbon Steels ◽  
Research Purpose ◽  
Elemental Content ◽  
High Tech ◽  
Urgent Task ◽  
Processing Modes

The creation of a universal, economical and high-tech way of increasing the life of both worn and new parts has become an urgent task. Such methods include nanostructuring of surface coatings, which can be performed by electric spark alloying. (Research purpose) The research purpose is studying the possibilities of electric spark alloying in the nanostructuring of the surface layer of carbon steels. (Materials and methods) The authors conducted study of the surface layer of 35-carbon steel with coatings obtained by electric spark alloying on the BIG-1 installation with different materials (Cu, Zn, W and WC) and at different modes. To study the surface layer, the elemental content was studied by x-ray fluorescence spectroscopy, the surface profile was studied by profiling, metallographic studies and microhardness measurements. (Results and discussion) The authors revealed that the chemical composition of the alloying electrode and treatment modes have a direct impact on the saturation of the surface layer with alloying elements, the parameters of the profile of the treated surface, the continuity and mechanical properties of the coating. It was found that harder processing modes increase productivity, but reduce mechanical properties. It was also found that the modified structure of the base material contains nanostructured elements because of electroscopic alloying. A sharp increase in the mechanical properties of the coating material allows suggesting that elements of the nanostructural range are present in the coating. (Conclusion) The conducted research shows that the method of electroscopic alloying can be used for nanostructuring of the surface layer of carbon steels.

scholarly journals Analysis of Different Complex Multilayer PACVD Coatings on Nanostructured WC-Co Cemented Carbide

Coatings ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 823
Author(s):  
Danko Ćorić ◽  
Mateja Šnajdar Musa ◽  
Matija Sakoman ◽  
Željko Alar
Keyword(s):  
Mechanical Properties ◽  
Surface Layer ◽  
Base Material ◽  
Single Layer ◽  
Production Costs ◽  
Structural Defects ◽  
Cemented Carbides ◽  
Material System ◽  
Tin Coating ◽  
Ticn Coating

The development of cemented carbides nowadays is aimed at the application and sintering of ultrafine and nano-sized powders for the production of a variety of components where excellent mechanical properties and high wear resistance are required for use in high temperature and corrosive environment conditions. The most efficient way of increasing the tribological properties along with achieving high corrosion resistance is coating. Using surface processes (modification and/or coating), it is possible to form a surface layer/base material system with properties that can meet modern expectations with acceptable production costs. Three coating systems were developed on WC cemented carbides substrate with the addition of 10 wt.% Co using the plasma-assisted chemical vapor deposition (PACVD) method: single-layer TiN coating, harder multilayer gradient TiCN coating composed of TiN and TiCN layers, and the hardest multilayer TiBN coating composed of TiN and TiB2. Physical and mechanical properties of coated and uncoated samples were investigated by means of quantitative depth profile (QDP) analysis, nanoindentation, surface layer characterization (XRD analysis), and coating adhesion evaluation using the scratch test. The results confirm the possibility of obtaining nanostructured cemented carbides of homogeneous structure without structural defects such as eta phase or unbound carbon providing increase in hardness and fracture toughness. The lowest adhesion was detected for the single-layer TiN coating, while coatings with a complex architecture (TiCN, TiBN) showed improved adhesion.

scholarly journals RESTORATION OF WOODEN DECORATIONS OF FACADES OF ANCIENT BUILDINGS IN CHERNIHIV

2020 ◽  
pp. 238-246
Author(s):  
Sergiy Boіko ◽  
◽  
Stanislav Ivashchenko ◽  
Andriy Yeroshenko ◽  
◽  
...  
Keyword(s):  
Computer Aided Design ◽  
High Efficiency ◽  
Wood Products ◽  
High Tech ◽  
Historic Buildings ◽  
Cnc Machines ◽  
Non Profit ◽  
Modern Computer ◽  
Urgent Task ◽  
Processing Modes

Urgency of the research. Increasing the productivity and level of automation of the process of manufacturing and restoration of elements of wooden architecture with the help of modern advanced equipment is one of the effective ways to revive the historic objects of wooden architecture in modern conditions.Target setting. The need to physically restore a large number of wooden carvings on the facades of historic buildings requires resources, both material and human. Therefore, the development of high-tech methods of restoring wood carvings on the historic facades of buildings, which save these resources is an urgent task in terms of ensuring high efficiency of machining of wood products and materials based on it.Actual scientific researches and issues analysis. Wooden carvings on the facades of houses used to be made by hand bya craftsman. Most of the existing literature and the recommendations given in it concern manual methods of manufacturing of a decor of facades, but considering a large number of repeating elements, they are not productive.Uninvestigated parts of general matters defining. Currently, there are a significant number of examples and proposals for the restoration of brick facades of historic buildings. Working with wooden facades decorated with carvings has its own features, which are not fully covered and require practical recommendations, taking into account the technical capabilities of modern equipment.The research objective ofthis article is to analyse the features of the use of modern technological equipment for manufacturing. and restoration of elements of wooden architecture.The statement of basic materials. The technology of production of wooden elements of decor of facades of houses by means of modern systems of the automated designing and CNC machines is considered. The influence on the nature of processing of processed materials, type of tool and processing modes is analysed.Conclusions. As part of the participation in the non-profit project "Wooden Lace of Chernihiv" for the first time used CNC machines and modern computer-aided design systems to restore the wooden architecture of Chernihiv region. The influence on the nature of processing of processed materials, type of tool and processing modes is analysed.

Vibroplasma hardening of the working bodies of agricultural machines

2020 ◽  
pp. 132-142
Author(s):  
Akmaral T. Bayniyazova ◽  
Marat M. Abzhaev ◽  
Elizaveta Yu. Kudryashova ◽  
Ildar A. Fayzrakhmanov ◽  
Said N. Sharifullin
Keyword(s):  
Surface Layer ◽  
Base Material ◽  
Physical And Mechanical Properties ◽  
Steel Sample ◽  
Research Purpose ◽  
Large Area ◽  
Main Components ◽  
Working Bodies ◽  
Thermal Influence ◽  
Agricultural Machines

The article describes the technology of hardening the working bodies of agricultural machines based on the use of the electric spark energy and vibration arc discharges or the energy of vibroplasma. (Research purpose). The research purpose is studying of the influence of vibroplasma treatment on the physical and mechanical properties of 65G steel, which is the main material of many working bodies of agricultural machinery. (Materials and methods). The studies were carried out on samples from a coulter disk of 30x30 mm with a thickness of 2 mm. The processing was carried out at VDGU-2 technological installations of electric spark alloying in accordance with the patent of the Russian Federation No. 2655420 and vibration arc hardening. Tungsten-cobalt and copper-graphite rods with diameters of 4 and 8 mm were used as electrodes. (Results and discussion). In contrast to the initial sample, the spectrum of the relatively large area of the 65G steel sample hardened by electrospark treatment showed that cobalt (4.92 percents) and tungsten (16.83 percents) are present in the treated layer in appreciable amounts. Measurements of the elemental composition of the local processing zone showed that the main components of this region are tungsten (64.20 percents) and cobalt (7.55 percent). Carbon, nitrogen, oxygen, iron, manganese, calcium, silicon, aluminum, and a number of other elements are present in the surface layer of the sample with a vibratory arc treatment, but at lower concentrations in comparison with the listed elements for the sample with electric spark treatment. It has been found that the main phases are carbide and iron oxide, as well as metallic iron. After treatment with vibroplasma, there is a so-called zone of thermal influence near the treated zone. (Conclusions). The surface layer formed by processing parts by vibroplasma represents a new composite structure consisting of three layers. The hardening of the base material in the depth of the part during electrospark machining occurs at 0.5-1.0 millimeter, with vibroplasma machining it is up to 3-4 millimeter. The microhardness of the surface layer of products increased by more than three times.

Adjusting Electricity Cost Depending on Power Supply Outages

2020 ◽  
Vol 67 (2) ◽  
pp. 44-50
Author(s):  
Vadim E. Bolshev ◽  
Aleksandr V. Vinogradov ◽  
Alina V. Vinogradova ◽  
Aleksey V. Bukreev ◽  
Aleksandr A. Lansberg
Keyword(s):  
Power Quality ◽  
Power Supply ◽  
Power Supply System ◽  
Economic Incentive ◽  
Supply System ◽  
Research Purpose ◽  
Electricity Cost ◽  
Economic Method ◽  
Urgent Task ◽  
Supply Reliability

During the functioning of power supply system, there can be situations where the culprit in interruptions of power supply to consumers and a power quality violation is a power supply company or a consumer himself. Therefore, the economic incentive for power supply companies and consumers to increase power supply reliability and power quality is an urgent task. To implement such incentives, it is necessary to control the facts and time of power supply outages and their values as well as cases and time of non-compliance of power quality with the requirements of standards. It is possible with the use of a monitoring system for power supply reliability and power quality. (Research purpose) The research purpose is in developing a technical and economic method for stimulating power supply companies and consumers to increase efficiency of power supply system. (Materials and methods) The article provides a review of the structural diagram of a system for monitoring power supply reliability and power quality including devices for monitoring the number and duration of power outages and voltage deviations. (Results and discussion). An economic method has been developed to stimulate power supply companies and consumers to increase power supply system efficiency. The essence of the method is to control the parameters of power supply reliability and power quality, identify the violation of these parameters, determine the culprit of the violation, determine the time characteristics of the violation, summarize the duration of violations for the reporting period, compare the actual amount of duration with the allowable one, determine the amount of compensation for the violation and impose sanctions on payment compensation by the perpetrators of violations of these parameters. The article presents an algorithm for adjusting the cost of electricity supplied to consumers depending on the number and duration of voltage deviations and the number and duration of outages. The algorithm serves to ensure the operation of the specified technical and economic method. (Conclusions) The algorithm works in conjunction with a system for monitoring power supply reliability and power quality based on signals from devices that control the number and duration of outages and voltage deviations.

Possibilities of using biodegradable polymeric materials in the agricultural sector

2020 ◽  
Vol 67 (2) ◽  
pp. 115-120
Author(s):  
Raisa A. Alekhina ◽  
Victoriya E. Slavkina ◽  
Yuliya A. Lopatina
Keyword(s):  
Mechanical Properties ◽  
Biodegradable Polymers ◽  
Biodegradable Polymer ◽  
Agricultural Sector ◽  
Polymeric Materials ◽  
Polymer Materials ◽  
Limiting Factors ◽  
Research Purpose ◽  
Biodegradable Materials ◽  
Advantages And Disadvantages

The article presents options for recycling polymers. The use of biodegradable materials is promising. This is a special class of polymers that can decompose under aerobic or anaerobic conditions under the action of microorganisms or enzymes forming natural products such as carbon dioxide, nitrogen, water, biomass, and inorganic salts. (Research purpose) The research purpose is in reviewing biodegradable materials that can be used for the manufacture of products used in agriculture. (Materials and methods) The study are based on open information sources containing information about biodegradable materials. Research methods are collecting, studying and comparative analysis of information. (Results and discussion) The article presents the advantages and disadvantages of biodegradable materials, mechanical properties of the main groups of biodegradable polymers. The article provides a summary list of agricultural products that can be made from biodegradable polymer materials. It was found that products from the general group are widely used in agriculture. Authors have found that products from a special group can only be made from biodegradable polymers with a controlled decomposition period in the soil, their use contributes to increasing the productivity of crops. (Conclusions) It was found that biodegradable polymer materials, along with environmental safety, have mechanical properties that allow them producing products that do not carry significant loads during operation. We have shown that the creation of responsible products (machine parts) from biodegradable polymers requires an increase in their strength properties, which is achievable by creating composites based on them. It was found that the technological complexity of their manufacture and high cost are the limiting factors for the widespread use of biodegradable polymers at this stage.

Conditions for the Effective Use of Air Curtain on Objects of Agricultural Production

2020 ◽  
Vol 67 (1) ◽  
pp. 54-59
Author(s):  
Aleksey V. Kuz’michev ◽  
Stanislav S. Trunov ◽  
Dmitriy A. Tikhomirov
Keyword(s):  
Agricultural Production ◽  
Theoretical Models ◽  
Research Purpose ◽  
Engineering Practice ◽  
Physical Factors ◽  
Air Curtain ◽  
Operating Modes ◽  
Air Jets ◽  
Urgent Task ◽  
Design Characteristics

Creating and maintaining a microclimate in animal housing is an energy-intensive technological process that consumes up to 70 percent of the thermal energy consumed on cattle farms. Improving heating and ventilation systems aimed at reducing energy consumption is an urgent task. (Research purpose) The research purpose is to analyze the theoretical models for calculating air curtains and evaluate the possibility of their use for agricultural production facilities and to identify promising directions in the design solutions for thermal air curtains aimed at rural consumers. (Materials and methods) The article considers the theoretical justification and calculation of air curtains. The authors studied the physical model of interaction of air jets in openings, which serves as the basis for mathematical calculation of air curtains in engineering practice. The article describes the features of using the models for calculating air curtains for agricultural objects and the energy parameters of the curtains depending on the design characteristics and external environmental factors. (Results and discussion) The effect of the air curtain on the energy characteristics of the room has been studied. It was found that it is necessary to determine the type of air curtain that is optimally suitable for protecting the gate opening, with or without heating the air curtain. Authors have found that the engineering methods of calculation are based on different experimental data, which leads to a discrepancy in the results of evaluating the effectiveness of the designed curtain, overestimating its energy intensity and power. The calculation of heat curtains, operating modes should be carried out taking into account the variable effects of external physical factors, the equipment should correspond to a specific room. (Conclusions) The use of air curtains reduces or eliminates the penetration of external cold air into the room through the openings of external gates, requires a smaller volume of air supplied by the curtain, compared to the mass of the incoming air flow.

ХАРАКТЕР ИЗМЕНЕНИЯ ГЛУБИНЫ ЛУЧЕВИДНОГО ИЗНОСА ПРИ РАЗЛИЧНЫХ ВАРИАНТАХ АРМИРОВАНИЯ ДОЛОТООБРАЗНОЙ ОБЛАСТИ ЛЕМЕХОВ ПРИ ВСПАШКЕ ТЯЖЕЛЫХ ПОЧВ

2020 ◽  
Vol 4 (141) ◽  
pp. 93-99
Author(s):  
ALEKSANDR MIKHAL’CHENKOV ◽  
◽  
NELLI KOZHUKHOVA ◽  
ANNA TYUREVA ◽  
VASILIY LUZIK
Keyword(s):  
Operating Time ◽  
Clay Content ◽  
Carbon Steels ◽  
Research Purpose ◽  
Wear Depth ◽  
Physical Clay ◽  
Shaped Part ◽  
Field Edge ◽  
Technological Methods ◽  
Minimum Wear

During the operation of the plow body, a number of defects are formed on the bit-shaped part of the plowshare, one of which is xiphoid wear. Renewing the life of a given part is often reduced to eliminating such wear in various ways that are not always rational. This occurs due to insufficient knowledge of the dynamics of xiphoid wear, especially little information about plowing heavy soils. (Research purpose) The research purpose is in identifying the nature of changes in the depth of xiphoid wear in various options for reinforcing the chisel-shaped area of ploughshares when plowing heavy soils. (Materials and methods) Authors conducted research using all-metal ploughshares of domestic production in the state of delivery and reinforced according to the schemes of the location of reinforcing rollers. The reinforcement rollers were formed using E42A-UONII-13/45 electrodes designed for welding carbon steels. The thickness in the area of the ploughshare wear was determined using a calibration plate, prisms, and an indicator micrometer with an accuracy of 0.01 millimeters. To ensure the same conditions of the experiment, it was carried out in fields where the soils had the same granulometric composition, which was loam with a physical clay content of 33-38 percent. (Results and discussion) The article reveals dynamics of the development of the xiphoid wear depth depending on the operating time and technological methods of strengthening reinforcement of the chisel-shaped part of the ploughshare. The article describes the technology of strengthening reinforcement that provides the minimum wear depth with the same operating time. (Conclusions) The article presents a method for determining the depth of xiphoid wear. The proposed technology of reinforcement of ploughshares with rollers perpendicular to the field edge, with surfacing of the buried part to a length of 100 millimeters and reinforcement of the heel will increase the resource of the part by 1.3 times.

Strategies of maintenance and repair of agricultural machinery

2020 ◽  
pp. 38-48
Author(s):  
Aleksey S. Dorokhov ◽  
Aleksandr V. Denisov ◽  
Aleksey A. Solomashkin ◽  
Valeriy S. Gerasimov
Keyword(s):  
Wear Rate ◽  
Technical Condition ◽  
Research Purpose ◽  
Agricultural Machinery ◽  
Maintenance And Repair ◽  
Wear Rates ◽  
Urgent Task ◽  
Machine Parts ◽  
Current Value ◽  
Agricultural Machines

Modern machines are subject to progressive wear that occurs at different rates, which leads to unpredictable failures that reduce the reliability and durability of machines. The strategy of maintenance and repair is aimed at eliminating these problems. (Research purpose) The research purpose is in analyzing the basic principles of the strategy of maintenance and repair of agricultural machinery in order to ensure control of the technical condition of machine parts. (Materials and methods) When resource diagnostics is used, , the allowable value of the parameter is set in advance for a part . This value is the tolerance that corresponds to a certain wear rate of the part. The tolerance is set based on the condition that if the current value of the controlled resource parameter during the next diagnosis is less than the set value, then such a part at the current value of the wear rate can be finalized until the next inter-control check. Taking into account the wear rate of the same type of parts from the group when determining the allowable wear during their resource diagnostics becomes an urgent task. (Results and discussions) As a result of research, the article presents "Methodology for determining the main indicators of reliability of parts of agricultural machines with different wear rates" and "Methodology for determining the tolerance system of parts of agricultural machines with different wear rates". (Conclusions) The article presents the tolerance system that reduces the probability of failure of machine parts in operation. During resource diagnostics, those parts whose resource parameters exceed the tolerance are rejected.

scholarly journals Assessment of Mechanical, Chemical, and Biological Properties of Ti-Nb-Zr Alloy for Medical Applications

Materials ◽  
2020 ◽  
Vol 14 (1) ◽  
pp. 126
Author(s):  
Viktoria Hoppe ◽  
Patrycja Szymczyk-Ziółkowska ◽  
Małgorzata Rusińska ◽  
Bogdan Dybała ◽  
Dominik Poradowski ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Corrosion Resistance ◽  
Base Material ◽  
Biological Properties ◽  
Β Phase ◽  
Alloy Base ◽  
Static Tensile ◽  
Examination Methods ◽  
13Zr Alloy ◽  
Dental Applications

The purpose of this work is to obtain comprehensive reference data of the Ti-13Nb-13Zr alloy base material: its microstructure, mechanical, and physicochemical properties. In order to obtain extensive information on the tested materials, a number of examination methods were used, including SEM, XRD, and XPS to determine the phases occurring in the material, while mechanical properties were verified with static tensile, compression, and bending tests. Moreover, the alloy’s corrosion resistance in Ringer’s solution and the cytotoxicity were investigated using the MTT test. Studies have shown that this alloy has the structure α’, α, and β phases, indicating that parts of the β phase transformed to α’, which was confirmed by mechanical properties and the shape of fractures. Due to the good mechanical properties (E = 84.1 GPa), high corrosion resistance, as well as the lack of cytotoxicity on MC3T3 and NHDF cells, this alloy meets the requirements for medical implant materials. Ti-13Nb-13Zr alloy can be successfully used in implants, including bone tissue engineering products and dental applications.

scholarly journals Corrosion Behavior, Microstructure and Mechanical Properties of Novel Mg-Zn-Ca-Er Alloy for Bio-Medical Applications

Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 519
Author(s):  
Devadas Bhat Panemangalore ◽  
Rajashekhara Shabadi ◽  
Manoj Gupta
Keyword(s):  
Mechanical Properties ◽  
Corrosion Behavior ◽  
Base Material ◽  
Hot Extrusion ◽  
Secondary Phases ◽  
Zinc Alloys ◽  
Alloying Additions ◽  
Degradation Rates ◽  
Master Alloys ◽  
Melt Deposition

In this study, the effect of calcium (Ca) and erbium (Er) on the microstructure, mechanical properties, and corrosion behavior of magnesium-zinc alloys is reported. The alloys were prepared using disintegrated melt deposition (DMD) technique using the alloying additions as Zn, Ca, and Mg-Er master alloys and followed by hot extrusion. Results show that alloying addition of Er has significantly reduced the grain sizes of Mg-Zn alloys and also when compared to pure magnesium base material. It also has substantially enhanced both the tensile and the compressive properties by favoring the formation of MgZn2 type secondary phases that are uniformly distributed during hot-extrusion. The quaternary Mg-Zn-Ca-Er alloy exhibited the highest strength due to lower grain size and particle strengthening due to the influence of the rare earth addition Er. The observed elongation was a result of extensive twinning observed in the alloys. Also, the degradation rates have been substantially reduced as a result of alloying additions and it is attributed to the barrier effect caused by the secondary phases.

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