Yury Korobov - Academia.edu (original) (raw)
Papers by Yury Korobov
Thermal spray, May 3, 2010
Analysis of melting mode of core wire at Arc Spraying helped to explain a possibility of incomple... more Analysis of melting mode of core wire at Arc Spraying helped to explain a possibility of incomplete fusion of a charge of a core wire. Influence of physicochemical parameters of feedstock and atomization modes was established. Analysis results helped to develop a metastable austenite type Core Wire for Arc Spraying of good wear resistance. Applications results are shown.
Проведено сравнение металоматричных покрытий вида NiCrB-WC на основе из бронзы С18150, полученных... more Проведено сравнение металоматричных покрытий вида NiCrB-WC на основе из бронзы С18150, полученных лазерной наплавкой на основе из бронзы CuCrZr. Проанализированы зависимости изменений структурных характеристик, твердости, склонности к образованию трещин от толщины покрытий и технологических параметров. Определены рациональные режимы обработки с использованием диодного лазера.
Key Engineering Materials, Apr 10, 2023
Metallurgist, Mar 1, 2017
Various methods are used for working surface treatment in order to prolong the life of machine co... more Various methods are used for working surface treatment in order to prolong the life of machine components subjected to different forms of wear. Deposition of coatings from the Fe-C-Cr-Ti-Al system is used extensively for protection from abrasive wear, although their lamellar and porous structure facilitates a reduction in wear resistance. Metallurgical processes are considered in this work in coatings prepared by arc metallizing of cored wire of the Fe-C-Cr-Ti-Al system and their effect on coating properties. ADM-10 activated arc metallization equipment is used to apply coatings. Remelting of sprayed coatings is performed in a universal unit for plasma treatment. It is carried out with direct current polarity using argon as a protective and plasma-forming gas. Results are provided for a study of the structure, microhardness and chemical composition of metallized coatings before and after remelting. Coating plasma treatment leads to remelting and a marked change in structure and microhardness. Coating microhardness increases considerably compared with the originally deposited coating. More uniform distribution is noted throughout the coating thickness that is due to a uniform coating structure, absence of oxide interlayers, porosity, and discontinuities, and also uniform chemical element distribution. It is established that oxidation of aluminum and titanium during sprayed coating plasma remelting facilitates the formation of a martensitic structure with strengthening by fi ne chromium carbide.
Ecology and the Environment, Apr 23, 2014
Machines used by the basic industries of Russia (metallurgy, oil-gas processing and power enginee... more Machines used by the basic industries of Russia (metallurgy, oil-gas processing and power engineering) are characterized by high metal consumption, which in turn lead to high energy consumption. Their service lives increase and their worn parts are restored by means of low-cost materials for restoration. The processes of Thermal Spraying (TS) are more effective than alternative methods in restoration and increase in service life. Such methods include electroplating, chemical and thermal processing. The results of research and experience have proven this. At the same time, the load on the environment is reduced in comparison with the alternatives by decreasing emissions. Based on OEM publications and our own experience, we analysed the efficiency of TS processes. Plasma spraying was excluded from consideration since it has no real alternative for refractory oxide coatings which are mainly used for gas turbines and jet engines. By the criteria of the coating's quality, performance and cost arc of spraying, flame spraying, HVOF/HVAF, cold spraying and detonation spraying were compared. Commonly used materials for TS, such as metals and carbides in metal bond (cermet), were examined as sprayed materials. This paper shows that a combination of activated arc spraying and HVAF for producing wear and corrosion-resistant coating is a rational variant with respect to a wide variety of parts for the aforementioned industries. Examples of resource-saving in metallurgy, oil-gas processing and power engineering are shown based on our own TS experience in material, equipment and technology development.
Welding International, 1998
Вестник Концерна ВКО «Алмаз – Антей», Dec 30, 2018
Снижение деформаций в тонколистовых конструкциях из высокопрочных сталей на основе САЕ-анализа св... more Снижение деформаций в тонколистовых конструкциях из высокопрочных сталей на основе САЕ-анализа сварных соединений Высокая конкуренция в области машиностроения требует изготовления облегченных тонколистовых конструкции из высокопрочных сталей с обеспечением геометрии определенной точности. Обеспечение заданной геометрии достижимо при совершенствовании мер снижения остаточных деформаций. Исследовано снижение деформации на основе анализа влияния жесткости прижима на напряженно-деформированное состояние сборки с помощью компьютерного моделирования методом конечных элементов. Получена модель прижима, позволяющая регулировать уровень остаточных напряжений и деформаций, подтвержденных экспериментальным путем. Ключевые слова: моделирование процесса сварки, напряженно-деформированное состояние, высокопрочные стали, сварочное приспособление, метод конечных элементов.
Welding International, 1997
Thermal Engineering, Feb 1, 2009
Features of gas-flame supersonic spraying (GFS) methods of coating are discussed. Comparison of t... more Features of gas-flame supersonic spraying (GFS) methods of coating are discussed. Comparison of typical models of equipment used for these processes—JP-5000, DJ, and Intelli-Jet units—is performed with respect to their gasdynamic parameters, spraying capacity, material utilization factor, and cost of coating application. Fields of their application are mentioned.
Welding International, 1997
Welding International, 2004
MATEC web of conferences, 2021
To assess the wear of the hot stamping tool, a model of punch deformation under the influence of ... more To assess the wear of the hot stamping tool, a model of punch deformation under the influence of thermal and mechanical loads was developed. The shape and relative position of the punch and die were designed to localize maximum contact loads at a predetermined location. It was assumed that the punch wear is caused by a removal of the surface metal layer, due to decreasing its mechanical strength during hot plastic deformation. Simulation was performed by the finite element method in the Deform software package. A temperature field and wear pattern in the contact zone were calculated. With respect to the loads typical for hot forging railway wheels, the comparison showed that the wear in a numerical experiment is of the same level as the actual value of wear.
IOP conference series, Nov 21, 2019
High competition in the field of mechanical engineering requires the manufacture of lightweight t... more High competition in the field of mechanical engineering requires the manufacture of lightweight thin-sheet structures made of high-strength steels ensuring the geometry of a certain accuracy. Supporting a given geometry is achievable by improving methods to reduce residual deformations. Therefore, the purpose of the investigation is to reduce the distortion based on the analysis of the influence of clamping rigidity on the stress-strain state of the assembly using computer simulation by the finite element method. The result of the study is a clamping model that allows to adjust the level of residual stresses and deformations, confirmed experimentally.
IOP conference series, Nov 21, 2019
For the process of multiple-electrode submerged arc welding (MESAW) of largediameter pipes (LDP) ... more For the process of multiple-electrode submerged arc welding (MESAW) of largediameter pipes (LDP) a mathematical model has been developed with a numerical solution in the software product "SYSWELD". The paper defines the parameters of double ellipsoid model of heat sources by J. Goldak. Using regression analysis of experimental data empirical formulas for calculating geometrical parameters of heat sources model by J. Goldak and deposition rate were developed for welding with direct current on positive polarity and alternating current. The model allows to predict the shape of weld and to estimate analytically the cooling rate in the heat affected zone (HAZ). The developed model and its numerical solutions with sufficient accuracy for practical calculations reflect the process of longitudinal welding of LDP.
Metallurgist, Mar 1, 2006
This article examines supersonic gas-flame methods of applying coatings. A comparative analysis i... more This article examines supersonic gas-flame methods of applying coatings. A comparative analysis is made of typical models of units used for these processes-the JP-5000, DJ Hybrid, and Intelli-Jet. The models are compared on the basis of their gasdynamic parameters, productivity, efficiency, and operating costs. Areas of application are also discussed. Within the last decade, researchers have developed high-intensity methods of applying powder coatings that are combined under such generic names as HVOF (High-Velocity Oxy-Fuel) or SGF (supersonic gas-flame) [1]. The materials that are applied-carbides and metals-form high-quality heat-, wear-, and corrosion-resistant films that can withstand chemically active and abrasive-percussive media and large thermal loads. The SGF method is successfully competing with alternative (cold gasdynamic-CHD, detonation-DD, and plasma-PD) methods of application on the basis of the quality of the coating, equipment cost, and the cost of the coating operation. The CHD method ensures the formation of high-quality coatings [2], but only with the use of materials having a relatively low melting point (Zn, Al, alloys of carbides and metals with large fraction of metallic matrix). Thus, this method cannot be used to protect parts and products from wear under erosive conditions or during service in aggressive media at high temperatures. It is also necessary to deliver the gases at pressures up to 2.2 MPa, which is difficult and dangerous under factory conditions. Comparison of the DD [3] and SGF [4-9] methods shows that the coatings are of comparable quality (with respect to adhesion, porosity, and degree of oxidation). However SGF methods are more productive and better-suited for industrial use, and the unit costs of the coating application are lower. In PD methods, the material being applied is heated 1000-3000 K above the melting point. This leads to intensive saturation of the particles by gases, low thermal efficiency, and high residual stresses in the coating. The use of a vacuum eliminates the first problem but increases the cost of the equipment. In terms of relative cost, SGF coatings are comparable to PD coatings and half the cost of DD and vacuum-plasma coatings [1]. Foreign manufacturers are currently using several hundred SGF units in different sectors of industry-machine construction, metallurgy, power generation, and aviation. More than 10 SGF systems are serially produced, and the Intelli-Jet system (made by the company Storm-ITS) and DJ Hybrid system (made by the German division of the firm Sulzer Metco) are available on the Russian market. Russian-made SGF units are either at the experimental stage or are inferior to their foreign counterparts with respect to their operating parameters. Data obtained from a comparative analysis of the most advanced systems and their features will be useful in refining their design and solving certain problems related to their industrial use. The temperature of the particles of the coating material in the SGF process is close to the melting point of the most common substrate metals, while their velocity is higher than in other methods (Fig. 1). This makes it possible to reduce the
Welding International, Jul 1, 2005
A promising direction of increasing the service life of components is the formation of the surfac... more A promising direction of increasing the service life of components is the formation of the surface layer which is in contact with the external medium and has improved properties. One of the rapidly developed directions is thermal spraying of coatings (TSC): gas-flame, plasma, detonation, electric arc metallising. In TSC, the surface of the component on which the coating is to be deposited is heated to temperatures below the tempering temperature. Therefore, the TSC processes are characterised by low thermal deformation and, in many cases, by the absence of structural changes in the material of the component. This results in the high efficiency of the TSC methods for improving the service characteristics of components. The results of analysis carried out by the consulting company The Technical Centre for Mechanical Engineers (CETIM), France, show that the world the volume of the market of TSC technologies in the year 2000 was €160 million, and the increase in the last decade was 25% (Fig. 1). According to technical and economic estimates, the relative cost of the components produced by electric arc metallising (EAM) is 3–10 times lower than that of the components produced by other TSC methods whilst ensuring high strength (Fig. 2). As regards the thermal efficiency, the cost of sprayed materials, productivity and efficiency of servicing, the EAM is preferred in comparison with other methods of deposition of thermal sprayed coatings. The effective efficiency of heating, i.e. the fraction of thermal energy, used directly for heating and melting of the sprayed material, in electric arc metallising is on average 60%. The low heat losses are determined by the physical special features of the process. Heating and melting of the sprayed material takes place as a result of the effect of the heat of the electric arc running between the electrodes producing the sprayed material. In other TSC processes, the generation of heat and consumption of heat for melting the sprayed material are separated in space and time resulting in high heat losses. In the most widely used process of plasma spraying (PS), the effective efficiency of heating is several times lower and equals 2–27%, depending on the type of sprayed material (wire or powder), and the design of the nozzle section. However, in addition to the advantages, the physical– chemical special features of the process of electric and metallising also result in difficulties in the production of high-quality coatings. If the nature of the forces acting on the droplet of the material in electric at metallising in the stage of spraying is identical with other TSC processes, in the initial stage of the formation of the two-phase flow there are considerable differences between these methods. In plasma spraying, the plasma jet receives the flow of spherical droplets, and the movement of these droplets is determined mainly by the force of aerodynamic drag on the side of the jet. Consequently, it is quite easy to produce the jet of the sprayed material. In EAM, in addition to the gas-dynamic pressure, the resultant properties strongly affected by the electromagnetic forces, formed in the arcing zone. Analysis shows 4 that of the resultant vector of the forces may greatly deviate from the required direction of movement of the droplets of Efficiency of using activated arc metallising for the deposition of protective coatings
Welding International, 1997
Thermal spray, May 3, 2010
Babbitt is used at tribology applications according to its low friction coefficient. Thermal spra... more Babbitt is used at tribology applications according to its low friction coefficient. Thermal spraying and pouring are widely used production processes of Babbitted parts. Comparative analysis of structure and wear properties of Babbitt layers produced by these technologies was done. Examples of typical arc sprayed Babbitted part's applications which were done at Mashprom are represented.
Journal of Friction and Wear, May 1, 2012
The authors have studied variations in such tribological characteristics as the friction coeffici... more The authors have studied variations in such tribological characteristics as the friction coefficient and wear rate of babbitt coatings obtained by the methods of turbulent casting, gas surfacing, plasma spraying, and activated arc metallization. The results obtained are discussed from the standpoints of microstructural metallographic analysis.
Fizika tverdogo tela, 2022
Al flux-cored wire surfacing was performed by laser, arc and hybrid methods. Laboratory tests hav... more Al flux-cored wire surfacing was performed by laser, arc and hybrid methods. Laboratory tests have shown that the deposited layers vary greatly in terms of wear resistance. To identify the reasons, studies were carried out using metallographic, X-ray structural and durometric methods. The analysis of the research results showed that the reason is the difference in the cooling rates of the deposited metal in the range of 1100−800 K. This difference leads to the possibility of the formation of a metastable austenitic structure, which, in turn, affects the wear resistance of the deposited layers.
Thermal spray, May 3, 2010
Analysis of melting mode of core wire at Arc Spraying helped to explain a possibility of incomple... more Analysis of melting mode of core wire at Arc Spraying helped to explain a possibility of incomplete fusion of a charge of a core wire. Influence of physicochemical parameters of feedstock and atomization modes was established. Analysis results helped to develop a metastable austenite type Core Wire for Arc Spraying of good wear resistance. Applications results are shown.
Проведено сравнение металоматричных покрытий вида NiCrB-WC на основе из бронзы С18150, полученных... more Проведено сравнение металоматричных покрытий вида NiCrB-WC на основе из бронзы С18150, полученных лазерной наплавкой на основе из бронзы CuCrZr. Проанализированы зависимости изменений структурных характеристик, твердости, склонности к образованию трещин от толщины покрытий и технологических параметров. Определены рациональные режимы обработки с использованием диодного лазера.
Key Engineering Materials, Apr 10, 2023
Metallurgist, Mar 1, 2017
Various methods are used for working surface treatment in order to prolong the life of machine co... more Various methods are used for working surface treatment in order to prolong the life of machine components subjected to different forms of wear. Deposition of coatings from the Fe-C-Cr-Ti-Al system is used extensively for protection from abrasive wear, although their lamellar and porous structure facilitates a reduction in wear resistance. Metallurgical processes are considered in this work in coatings prepared by arc metallizing of cored wire of the Fe-C-Cr-Ti-Al system and their effect on coating properties. ADM-10 activated arc metallization equipment is used to apply coatings. Remelting of sprayed coatings is performed in a universal unit for plasma treatment. It is carried out with direct current polarity using argon as a protective and plasma-forming gas. Results are provided for a study of the structure, microhardness and chemical composition of metallized coatings before and after remelting. Coating plasma treatment leads to remelting and a marked change in structure and microhardness. Coating microhardness increases considerably compared with the originally deposited coating. More uniform distribution is noted throughout the coating thickness that is due to a uniform coating structure, absence of oxide interlayers, porosity, and discontinuities, and also uniform chemical element distribution. It is established that oxidation of aluminum and titanium during sprayed coating plasma remelting facilitates the formation of a martensitic structure with strengthening by fi ne chromium carbide.
Ecology and the Environment, Apr 23, 2014
Machines used by the basic industries of Russia (metallurgy, oil-gas processing and power enginee... more Machines used by the basic industries of Russia (metallurgy, oil-gas processing and power engineering) are characterized by high metal consumption, which in turn lead to high energy consumption. Their service lives increase and their worn parts are restored by means of low-cost materials for restoration. The processes of Thermal Spraying (TS) are more effective than alternative methods in restoration and increase in service life. Such methods include electroplating, chemical and thermal processing. The results of research and experience have proven this. At the same time, the load on the environment is reduced in comparison with the alternatives by decreasing emissions. Based on OEM publications and our own experience, we analysed the efficiency of TS processes. Plasma spraying was excluded from consideration since it has no real alternative for refractory oxide coatings which are mainly used for gas turbines and jet engines. By the criteria of the coating's quality, performance and cost arc of spraying, flame spraying, HVOF/HVAF, cold spraying and detonation spraying were compared. Commonly used materials for TS, such as metals and carbides in metal bond (cermet), were examined as sprayed materials. This paper shows that a combination of activated arc spraying and HVAF for producing wear and corrosion-resistant coating is a rational variant with respect to a wide variety of parts for the aforementioned industries. Examples of resource-saving in metallurgy, oil-gas processing and power engineering are shown based on our own TS experience in material, equipment and technology development.
Welding International, 1998
Вестник Концерна ВКО «Алмаз – Антей», Dec 30, 2018
Снижение деформаций в тонколистовых конструкциях из высокопрочных сталей на основе САЕ-анализа св... more Снижение деформаций в тонколистовых конструкциях из высокопрочных сталей на основе САЕ-анализа сварных соединений Высокая конкуренция в области машиностроения требует изготовления облегченных тонколистовых конструкции из высокопрочных сталей с обеспечением геометрии определенной точности. Обеспечение заданной геометрии достижимо при совершенствовании мер снижения остаточных деформаций. Исследовано снижение деформации на основе анализа влияния жесткости прижима на напряженно-деформированное состояние сборки с помощью компьютерного моделирования методом конечных элементов. Получена модель прижима, позволяющая регулировать уровень остаточных напряжений и деформаций, подтвержденных экспериментальным путем. Ключевые слова: моделирование процесса сварки, напряженно-деформированное состояние, высокопрочные стали, сварочное приспособление, метод конечных элементов.
Welding International, 1997
Thermal Engineering, Feb 1, 2009
Features of gas-flame supersonic spraying (GFS) methods of coating are discussed. Comparison of t... more Features of gas-flame supersonic spraying (GFS) methods of coating are discussed. Comparison of typical models of equipment used for these processes—JP-5000, DJ, and Intelli-Jet units—is performed with respect to their gasdynamic parameters, spraying capacity, material utilization factor, and cost of coating application. Fields of their application are mentioned.
Welding International, 1997
Welding International, 2004
MATEC web of conferences, 2021
To assess the wear of the hot stamping tool, a model of punch deformation under the influence of ... more To assess the wear of the hot stamping tool, a model of punch deformation under the influence of thermal and mechanical loads was developed. The shape and relative position of the punch and die were designed to localize maximum contact loads at a predetermined location. It was assumed that the punch wear is caused by a removal of the surface metal layer, due to decreasing its mechanical strength during hot plastic deformation. Simulation was performed by the finite element method in the Deform software package. A temperature field and wear pattern in the contact zone were calculated. With respect to the loads typical for hot forging railway wheels, the comparison showed that the wear in a numerical experiment is of the same level as the actual value of wear.
IOP conference series, Nov 21, 2019
High competition in the field of mechanical engineering requires the manufacture of lightweight t... more High competition in the field of mechanical engineering requires the manufacture of lightweight thin-sheet structures made of high-strength steels ensuring the geometry of a certain accuracy. Supporting a given geometry is achievable by improving methods to reduce residual deformations. Therefore, the purpose of the investigation is to reduce the distortion based on the analysis of the influence of clamping rigidity on the stress-strain state of the assembly using computer simulation by the finite element method. The result of the study is a clamping model that allows to adjust the level of residual stresses and deformations, confirmed experimentally.
IOP conference series, Nov 21, 2019
For the process of multiple-electrode submerged arc welding (MESAW) of largediameter pipes (LDP) ... more For the process of multiple-electrode submerged arc welding (MESAW) of largediameter pipes (LDP) a mathematical model has been developed with a numerical solution in the software product "SYSWELD". The paper defines the parameters of double ellipsoid model of heat sources by J. Goldak. Using regression analysis of experimental data empirical formulas for calculating geometrical parameters of heat sources model by J. Goldak and deposition rate were developed for welding with direct current on positive polarity and alternating current. The model allows to predict the shape of weld and to estimate analytically the cooling rate in the heat affected zone (HAZ). The developed model and its numerical solutions with sufficient accuracy for practical calculations reflect the process of longitudinal welding of LDP.
Metallurgist, Mar 1, 2006
This article examines supersonic gas-flame methods of applying coatings. A comparative analysis i... more This article examines supersonic gas-flame methods of applying coatings. A comparative analysis is made of typical models of units used for these processes-the JP-5000, DJ Hybrid, and Intelli-Jet. The models are compared on the basis of their gasdynamic parameters, productivity, efficiency, and operating costs. Areas of application are also discussed. Within the last decade, researchers have developed high-intensity methods of applying powder coatings that are combined under such generic names as HVOF (High-Velocity Oxy-Fuel) or SGF (supersonic gas-flame) [1]. The materials that are applied-carbides and metals-form high-quality heat-, wear-, and corrosion-resistant films that can withstand chemically active and abrasive-percussive media and large thermal loads. The SGF method is successfully competing with alternative (cold gasdynamic-CHD, detonation-DD, and plasma-PD) methods of application on the basis of the quality of the coating, equipment cost, and the cost of the coating operation. The CHD method ensures the formation of high-quality coatings [2], but only with the use of materials having a relatively low melting point (Zn, Al, alloys of carbides and metals with large fraction of metallic matrix). Thus, this method cannot be used to protect parts and products from wear under erosive conditions or during service in aggressive media at high temperatures. It is also necessary to deliver the gases at pressures up to 2.2 MPa, which is difficult and dangerous under factory conditions. Comparison of the DD [3] and SGF [4-9] methods shows that the coatings are of comparable quality (with respect to adhesion, porosity, and degree of oxidation). However SGF methods are more productive and better-suited for industrial use, and the unit costs of the coating application are lower. In PD methods, the material being applied is heated 1000-3000 K above the melting point. This leads to intensive saturation of the particles by gases, low thermal efficiency, and high residual stresses in the coating. The use of a vacuum eliminates the first problem but increases the cost of the equipment. In terms of relative cost, SGF coatings are comparable to PD coatings and half the cost of DD and vacuum-plasma coatings [1]. Foreign manufacturers are currently using several hundred SGF units in different sectors of industry-machine construction, metallurgy, power generation, and aviation. More than 10 SGF systems are serially produced, and the Intelli-Jet system (made by the company Storm-ITS) and DJ Hybrid system (made by the German division of the firm Sulzer Metco) are available on the Russian market. Russian-made SGF units are either at the experimental stage or are inferior to their foreign counterparts with respect to their operating parameters. Data obtained from a comparative analysis of the most advanced systems and their features will be useful in refining their design and solving certain problems related to their industrial use. The temperature of the particles of the coating material in the SGF process is close to the melting point of the most common substrate metals, while their velocity is higher than in other methods (Fig. 1). This makes it possible to reduce the
Welding International, Jul 1, 2005
A promising direction of increasing the service life of components is the formation of the surfac... more A promising direction of increasing the service life of components is the formation of the surface layer which is in contact with the external medium and has improved properties. One of the rapidly developed directions is thermal spraying of coatings (TSC): gas-flame, plasma, detonation, electric arc metallising. In TSC, the surface of the component on which the coating is to be deposited is heated to temperatures below the tempering temperature. Therefore, the TSC processes are characterised by low thermal deformation and, in many cases, by the absence of structural changes in the material of the component. This results in the high efficiency of the TSC methods for improving the service characteristics of components. The results of analysis carried out by the consulting company The Technical Centre for Mechanical Engineers (CETIM), France, show that the world the volume of the market of TSC technologies in the year 2000 was €160 million, and the increase in the last decade was 25% (Fig. 1). According to technical and economic estimates, the relative cost of the components produced by electric arc metallising (EAM) is 3–10 times lower than that of the components produced by other TSC methods whilst ensuring high strength (Fig. 2). As regards the thermal efficiency, the cost of sprayed materials, productivity and efficiency of servicing, the EAM is preferred in comparison with other methods of deposition of thermal sprayed coatings. The effective efficiency of heating, i.e. the fraction of thermal energy, used directly for heating and melting of the sprayed material, in electric arc metallising is on average 60%. The low heat losses are determined by the physical special features of the process. Heating and melting of the sprayed material takes place as a result of the effect of the heat of the electric arc running between the electrodes producing the sprayed material. In other TSC processes, the generation of heat and consumption of heat for melting the sprayed material are separated in space and time resulting in high heat losses. In the most widely used process of plasma spraying (PS), the effective efficiency of heating is several times lower and equals 2–27%, depending on the type of sprayed material (wire or powder), and the design of the nozzle section. However, in addition to the advantages, the physical– chemical special features of the process of electric and metallising also result in difficulties in the production of high-quality coatings. If the nature of the forces acting on the droplet of the material in electric at metallising in the stage of spraying is identical with other TSC processes, in the initial stage of the formation of the two-phase flow there are considerable differences between these methods. In plasma spraying, the plasma jet receives the flow of spherical droplets, and the movement of these droplets is determined mainly by the force of aerodynamic drag on the side of the jet. Consequently, it is quite easy to produce the jet of the sprayed material. In EAM, in addition to the gas-dynamic pressure, the resultant properties strongly affected by the electromagnetic forces, formed in the arcing zone. Analysis shows 4 that of the resultant vector of the forces may greatly deviate from the required direction of movement of the droplets of Efficiency of using activated arc metallising for the deposition of protective coatings
Welding International, 1997
Thermal spray, May 3, 2010
Babbitt is used at tribology applications according to its low friction coefficient. Thermal spra... more Babbitt is used at tribology applications according to its low friction coefficient. Thermal spraying and pouring are widely used production processes of Babbitted parts. Comparative analysis of structure and wear properties of Babbitt layers produced by these technologies was done. Examples of typical arc sprayed Babbitted part's applications which were done at Mashprom are represented.
Journal of Friction and Wear, May 1, 2012
The authors have studied variations in such tribological characteristics as the friction coeffici... more The authors have studied variations in such tribological characteristics as the friction coefficient and wear rate of babbitt coatings obtained by the methods of turbulent casting, gas surfacing, plasma spraying, and activated arc metallization. The results obtained are discussed from the standpoints of microstructural metallographic analysis.
Fizika tverdogo tela, 2022
Al flux-cored wire surfacing was performed by laser, arc and hybrid methods. Laboratory tests hav... more Al flux-cored wire surfacing was performed by laser, arc and hybrid methods. Laboratory tests have shown that the deposited layers vary greatly in terms of wear resistance. To identify the reasons, studies were carried out using metallographic, X-ray structural and durometric methods. The analysis of the research results showed that the reason is the difference in the cooling rates of the deposited metal in the range of 1100−800 K. This difference leads to the possibility of the formation of a metastable austenitic structure, which, in turn, affects the wear resistance of the deposited layers.