Pub Date : 2023-03-15DOI: 10.17212/1994-6309-2023-25.1-57-70
S. Bratan, A. Chasovitina
Introduction. In real production conditions, the technological modes recommended in the scientific literature do not reflect the declared qualities, due to the fact that it does not take into account many factors inherent in the process of finishing grinding, for example, its stochastic nature, changes in its dynamic properties, an increase in mutual vibrations of the tool and the workpiece that appear due to changes in the state of the technological system, for example, an increase in vibrations machine tool due to uneven tool wear, etc. All previously developed models have a limited scope of application, it does not take into account the fact that the appearance of vibrations leads to fluctuations in the depth of grinding, with accidental contact of grains with the material being processed, where one group of grains cuts off the material, the other gets into the trace of scratches left by previous grains, etc. This leads to changes in the values of material removal, surface roughness and other parameters of the technological system, which directly affects the accuracy of processing and the quality of the machined surfaces. The purpose of the work is to develop mathematical models that establish the relationship between the processing modes and the current parameters of the contact zone during the fine grinding of pinholes, taking into account the mutual vibrations of the tool and the workpiece. The research methods are mathematical simulation using the basic provisions of the theory of abrasive-diamond processing. Results and discussion. The interrelations between the cutting modes and the current input parameters of the contact zone when grinding pinholes are established, taking into account the mutual vibrations of the tool and the workpiece, which make it possible to determine the parameters of the system at the output to avoid cost losses, including reducing the number of defective products and time costs. Non-stationary mathematical dependences are constructed that allow determining the cutting modes during the implementation of the grinding cycle, taking into account the magnitude of relative vibrations and the initial phase. It is established that instead of a steady process, harmonic oscillations are observed caused by deviations in the shape of the circle, the intensity of tool wear and other factors, all of the above has a significant impact on the quality of the machined surface. The obtained models are universal for various characteristics of the tool, however, for a more adequate description of the process, mathematical dependencies are needed that take into account the wear of the tool on various binders, which is the task of further research.
{"title":"Simulation of the relationship between input factors and output indicators of the internal grinding process, considering the mutual vibrations of the tool and the workpiece","authors":"S. Bratan, A. Chasovitina","doi":"10.17212/1994-6309-2023-25.1-57-70","DOIUrl":"https://doi.org/10.17212/1994-6309-2023-25.1-57-70","url":null,"abstract":"Introduction. In real production conditions, the technological modes recommended in the scientific literature do not reflect the declared qualities, due to the fact that it does not take into account many factors inherent in the process of finishing grinding, for example, its stochastic nature, changes in its dynamic properties, an increase in mutual vibrations of the tool and the workpiece that appear due to changes in the state of the technological system, for example, an increase in vibrations machine tool due to uneven tool wear, etc. All previously developed models have a limited scope of application, it does not take into account the fact that the appearance of vibrations leads to fluctuations in the depth of grinding, with accidental contact of grains with the material being processed, where one group of grains cuts off the material, the other gets into the trace of scratches left by previous grains, etc. This leads to changes in the values of material removal, surface roughness and other parameters of the technological system, which directly affects the accuracy of processing and the quality of the machined surfaces. The purpose of the work is to develop mathematical models that establish the relationship between the processing modes and the current parameters of the contact zone during the fine grinding of pinholes, taking into account the mutual vibrations of the tool and the workpiece. The research methods are mathematical simulation using the basic provisions of the theory of abrasive-diamond processing. Results and discussion. The interrelations between the cutting modes and the current input parameters of the contact zone when grinding pinholes are established, taking into account the mutual vibrations of the tool and the workpiece, which make it possible to determine the parameters of the system at the output to avoid cost losses, including reducing the number of defective products and time costs. Non-stationary mathematical dependences are constructed that allow determining the cutting modes during the implementation of the grinding cycle, taking into account the magnitude of relative vibrations and the initial phase. It is established that instead of a steady process, harmonic oscillations are observed caused by deviations in the shape of the circle, the intensity of tool wear and other factors, all of the above has a significant impact on the quality of the machined surface. The obtained models are universal for various characteristics of the tool, however, for a more adequate description of the process, mathematical dependencies are needed that take into account the wear of the tool on various binders, which is the task of further research.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49094130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-15DOI: 10.17212/1994-6309-2023-25.1-98-109
A. Sokolov, E. Bobylyov, R. Popov
Introduction. The main methods of increasing the efficiency of products made from structural steels are considered. A description of diffusion saturation from liquid metal media solutions (DSLMMS) is given. Also, complex diffusion saturation technology (CDS), including DSLMMS and carburization is shown. The purpose of the work is to reveal the effect of steel composition on the process of formation and elemental composition of diffusion-saturated surface layers (coatings) based on chromium, as well as to establish differences and regularities in the processes of formation of diffusion-saturated coatings after DSLMMS and CDS. The methods of investigation. Cylindrical specimens 20 mm in diameter and 30 mm long were subjected to DSLMMS. The specimens were made of carbon and alloyed steels: St3, 20-Cr13, 40-Cr, 40-Cr13, 12-Cr18-Ni10-Ti. At the same time, some of the specimens were previously subjected to vacuum cementation. An eutectic Pb-Bi with the specified content of Cr was used as a transport medium when executing DSLMMS. Metallographic studies were carried out on microsection prepared according to the standard method. Studies to determine the thickness of coatings and its structure were carried out on the Dura Scan Falcon 500 Microhardness Tester. The elemental composition of the coatings was determined by the method of electron microprobe analysis on a Tescan Lyra 3 scanning electron microscope with the Oxford Ultim MAX PCMA system. Results and discussion. As a result of the research, it was revealed that the formation of saturated coatings occurs with DSLMMS and CDS. At the same time, the thickness of the coatings and its elemental composition depend on the steel grade and the technology used. After DSLMMS concentration of Cr varies from 96.9% to 91.1%. At the same time, the maximum concentration of 96.9% is observed on steel St3. After CDS, on the surfaces of all steel samples, the concentration of Cr decreases in comparison with the coatings obtained by the DSLMMS technology on steels: St3 from 96.9% to 66.8%; 40-Cr from 91.1% to 63.18%; 20-Cr13 from 93.18% to 62.54%; 12-Cr18-Ni10-Ti from 92.92% to 64.77%. The total thickness of diffusion-saturated coatings formed on all the alloys studied ranges from 17 to 17.5 µm.
介绍考虑了提高结构钢产品效率的主要方法。给出了液态金属介质溶液扩散饱和的描述。此外，还介绍了复合扩散饱和技术（CDS），包括DSLMMS和渗碳。本工作的目的是揭示钢成分对基于铬的扩散饱和表面层（涂层）形成过程和元素组成的影响，以及建立DSLMMS和CDS后扩散饱和涂层形成过程的差异和规律。调查方法。对直径为20mm、长度为30mm的圆柱形试样进行DSLMMS。试样由碳钢和合金钢制成：St3、20-Cr13、40Cr、40-Cr13、12-Cr18-Ni10-Ti。同时，一些试样之前进行了真空胶结。在执行DSLMMS时，使用具有特定Cr含量的共晶Pb-Bi作为传输介质。对根据标准方法制备的显微切片进行了金相研究。在Dura Scan Falcon 500显微硬度计上进行了测定涂层厚度及其结构的研究。涂层的元素组成通过电子探针分析方法在具有Oxford Ultim MAX PCMA系统的Tescan Lyra 3扫描电子显微镜上测定。结果和讨论。研究结果表明，DSLMMS和CDS会形成饱和涂层。同时，涂层的厚度及其元素组成取决于钢的等级和所使用的技术。DSLMMS后Cr的浓度在96.9%~91.1%之间变化，同时在St3钢上观察到最大浓度为96.9%。CDS后，在所有钢样品的表面上，与DSLMMS技术在钢上获得的涂层相比，Cr的浓度降低：St3从96.9%降低到66.8%；40Cr从91.1%提高到63.18%；20-Cr13从93.18%提高到62.54%；12-Cr18-Ni10-Ti从92.92%到64.77%。在所有研究的合金上形成的扩散饱和涂层的总厚度范围为17到17.5µm。
{"title":"Diffusion coatings formation features, obtained by complex chemical-thermal treatment on the structural steels","authors":"A. Sokolov, E. Bobylyov, R. Popov","doi":"10.17212/1994-6309-2023-25.1-98-109","DOIUrl":"https://doi.org/10.17212/1994-6309-2023-25.1-98-109","url":null,"abstract":"Introduction. The main methods of increasing the efficiency of products made from structural steels are considered. A description of diffusion saturation from liquid metal media solutions (DSLMMS) is given. Also, complex diffusion saturation technology (CDS), including DSLMMS and carburization is shown. The purpose of the work is to reveal the effect of steel composition on the process of formation and elemental composition of diffusion-saturated surface layers (coatings) based on chromium, as well as to establish differences and regularities in the processes of formation of diffusion-saturated coatings after DSLMMS and CDS. The methods of investigation. Cylindrical specimens 20 mm in diameter and 30 mm long were subjected to DSLMMS. The specimens were made of carbon and alloyed steels: St3, 20-Cr13, 40-Cr, 40-Cr13, 12-Cr18-Ni10-Ti. At the same time, some of the specimens were previously subjected to vacuum cementation. An eutectic Pb-Bi with the specified content of Cr was used as a transport medium when executing DSLMMS. Metallographic studies were carried out on microsection prepared according to the standard method. Studies to determine the thickness of coatings and its structure were carried out on the Dura Scan Falcon 500 Microhardness Tester. The elemental composition of the coatings was determined by the method of electron microprobe analysis on a Tescan Lyra 3 scanning electron microscope with the Oxford Ultim MAX PCMA system. Results and discussion. As a result of the research, it was revealed that the formation of saturated coatings occurs with DSLMMS and CDS. At the same time, the thickness of the coatings and its elemental composition depend on the steel grade and the technology used. After DSLMMS concentration of Cr varies from 96.9% to 91.1%. At the same time, the maximum concentration of 96.9% is observed on steel St3. After CDS, on the surfaces of all steel samples, the concentration of Cr decreases in comparison with the coatings obtained by the DSLMMS technology on steels: St3 from 96.9% to 66.8%; 40-Cr from 91.1% to 63.18%; 20-Cr13 from 93.18% to 62.54%; 12-Cr18-Ni10-Ti from 92.92% to 64.77%. The total thickness of diffusion-saturated coatings formed on all the alloys studied ranges from 17 to 17.5 µm.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":"122 9","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41311775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-15DOI: 10.17212/1994-6309-2023-25.1-131-148
S. Lysykh, V. Kornopoltsev, U. Mishigdorzhiyn, Yu. P. Kharaev, A. Tikhonov, V. Ivancivsky, N. Vakhrushev
Introduction. Borocoppering is one of the methods of thermochemical treatment (TCT) aimed at forming diffusion layers with high physical and mechanical properties on the surface of carbon and alloy steels. The thickness of the diffusion layer is the most important characteristic of the TCT, which determines the depth of hardening. Consequently, the intensity and main characteristics of the TCT (layer thickness, alloying element concentration profile) depend on the process conditions (temperature, duration, and amount of alloying element). The purpose of this work is to determine the temperature-time parameters of diffusion borocoppering, which contribute to the formation of diffusion layers with a maximum thickness. The paper considers the results of surface hardening of carbon and alloy steels (for example, Steel 45 (0.45% C), Steel U10 (1.0% C), and 0.5C-Cr-Ni-Mn steel) by high-temperature soaking in powder mixtures containing boron and copper. Borocoppering was carried out in sealed containers with the powder mixture consisting of boron carbide, copper oxide, and sodium fluoride as an activator at a temperature of 950 °C for 3–5 h. The resulting specimens with a diffusion layer were examined using an optical microscope and a scanning electron microscope (SEM); the microhardness, elemental and phase composition of the layers were also determined, as well as the roughness of the obtained surfaces. Results and discussions. The microstructure of the obtained diffusion layers is studied; diagrams of the changes in the layers’ thickness and the microhardness distribution over the layers’ thickness are shown. It is established that with an increase in the soaking time from 3 to 5 h, the thickness of the diffusion layer increases from 120 to 170 μm on Steel 45 (0.45% C); from 110 to 155 µm on Steel U10 (1.0% C) and from 130 to 230 µm on 0.5C-Cr-Ni-Mn steel. A gradual decrease in the concentration of boron and copper along the layer thickness from 15–16% and 2–3% on the surface, respectively, to zero values at the boundary with the base metal is revealed. It is established that borocoppering to the formation of more thick boride layers on the surface of carbon and alloy steels compared to pure boriding. Moreover, an increase in the duration of soaking during the process contributes to the greatest increase in the thickness of the layer on 0.5C-Cr-Ni-Mn steel. A study of microgeometry is carried out, microtopographies and profilograms of specimens’ surfaces are shown before and after borocoppering. It is established that the roughness after borocoppering increases by 2-3 times compared to the initial one, and an increase in the duration of the process does not have a significant effect on the roughness.
{"title":"The effect of borocoppering duration on the composition, microstructure and microhardness of the surface of carbon and alloy steels","authors":"S. Lysykh, V. Kornopoltsev, U. Mishigdorzhiyn, Yu. P. Kharaev, A. Tikhonov, V. Ivancivsky, N. Vakhrushev","doi":"10.17212/1994-6309-2023-25.1-131-148","DOIUrl":"https://doi.org/10.17212/1994-6309-2023-25.1-131-148","url":null,"abstract":"Introduction. Borocoppering is one of the methods of thermochemical treatment (TCT) aimed at forming diffusion layers with high physical and mechanical properties on the surface of carbon and alloy steels. The thickness of the diffusion layer is the most important characteristic of the TCT, which determines the depth of hardening. Consequently, the intensity and main characteristics of the TCT (layer thickness, alloying element concentration profile) depend on the process conditions (temperature, duration, and amount of alloying element). The purpose of this work is to determine the temperature-time parameters of diffusion borocoppering, which contribute to the formation of diffusion layers with a maximum thickness. The paper considers the results of surface hardening of carbon and alloy steels (for example, Steel 45 (0.45% C), Steel U10 (1.0% C), and 0.5C-Cr-Ni-Mn steel) by high-temperature soaking in powder mixtures containing boron and copper. Borocoppering was carried out in sealed containers with the powder mixture consisting of boron carbide, copper oxide, and sodium fluoride as an activator at a temperature of 950 °C for 3–5 h. The resulting specimens with a diffusion layer were examined using an optical microscope and a scanning electron microscope (SEM); the microhardness, elemental and phase composition of the layers were also determined, as well as the roughness of the obtained surfaces. Results and discussions. The microstructure of the obtained diffusion layers is studied; diagrams of the changes in the layers’ thickness and the microhardness distribution over the layers’ thickness are shown. It is established that with an increase in the soaking time from 3 to 5 h, the thickness of the diffusion layer increases from 120 to 170 μm on Steel 45 (0.45% C); from 110 to 155 µm on Steel U10 (1.0% C) and from 130 to 230 µm on 0.5C-Cr-Ni-Mn steel. A gradual decrease in the concentration of boron and copper along the layer thickness from 15–16% and 2–3% on the surface, respectively, to zero values at the boundary with the base metal is revealed. It is established that borocoppering to the formation of more thick boride layers on the surface of carbon and alloy steels compared to pure boriding. Moreover, an increase in the duration of soaking during the process contributes to the greatest increase in the thickness of the layer on 0.5C-Cr-Ni-Mn steel. A study of microgeometry is carried out, microtopographies and profilograms of specimens’ surfaces are shown before and after borocoppering. It is established that the roughness after borocoppering increases by 2-3 times compared to the initial one, and an increase in the duration of the process does not have a significant effect on the roughness.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46879821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-15DOI: 10.17212/1994-6309-2023-25.1-44-56
M. Gimadeev, A. Li, V. Berkun, V. Stelmakov
Introduction. Due to a significant number of factors affecting the change in the properties of a dynamic system, excessively conservative processing conditions are chosen to ensure the high quality of the resulting product. This limits the efficiency of the process and leads to an increase in the cost of production. Accordingly, modern approaches are needed that will allow diagnosing the current state of processing and making timely decisions to replace the tool, correct or change the control program. The significance of the ongoing research is to propose a real-time monitoring approach to milling control to identify emerging processing errors, predict potential problems and improve uptime. Subject. The paper discusses the features of the real-time monitoring system during mechanical processing with a single- and double-edge cutting tool, taking into account acoustic wave filtering, minimizing surface roughness. The purpose of the work is to determine the effect of the inclination orientation of the ball-end tool on the surface roughness value using real-time monitoring during milling on CNC process equipment. Methods. The study provides methods of correlation and regression analysis. The calculated data were obtained by means of vibroacoustic diagnostics and measured in the range of values of the variable angle of inclination of the surface for single- and double-edge cutting tool based on the provisions of the theory of oscillations and vibroacoustic diagnostics, cutting theory, digital processing and digital filtering of signals. Results and discussions. Experimental data obtained during machining made it possible to determine that an increase in the angle of inclination of a single-edge cutting tool has practically no effect on the change in the amplitude parameters of roughness. The values of vibroacoustic diagnostics and roughness, when using a double-edge ball-end tool, show a consistent picture with the effects created by the angles of inclination and advance. The obtained solutions to the problems of monitoring and analyzing the roughness parameters can significantly reduce the amount of experimental research and clarify the idea of the practical implementation of the method of acoustic monitoring of the cutting process.
{"title":"Experimental study of the dynamics of the machining process by ball-end mills","authors":"M. Gimadeev, A. Li, V. Berkun, V. Stelmakov","doi":"10.17212/1994-6309-2023-25.1-44-56","DOIUrl":"https://doi.org/10.17212/1994-6309-2023-25.1-44-56","url":null,"abstract":"Introduction. Due to a significant number of factors affecting the change in the properties of a dynamic system, excessively conservative processing conditions are chosen to ensure the high quality of the resulting product. This limits the efficiency of the process and leads to an increase in the cost of production. Accordingly, modern approaches are needed that will allow diagnosing the current state of processing and making timely decisions to replace the tool, correct or change the control program. The significance of the ongoing research is to propose a real-time monitoring approach to milling control to identify emerging processing errors, predict potential problems and improve uptime. Subject. The paper discusses the features of the real-time monitoring system during mechanical processing with a single- and double-edge cutting tool, taking into account acoustic wave filtering, minimizing surface roughness. The purpose of the work is to determine the effect of the inclination orientation of the ball-end tool on the surface roughness value using real-time monitoring during milling on CNC process equipment. Methods. The study provides methods of correlation and regression analysis. The calculated data were obtained by means of vibroacoustic diagnostics and measured in the range of values of the variable angle of inclination of the surface for single- and double-edge cutting tool based on the provisions of the theory of oscillations and vibroacoustic diagnostics, cutting theory, digital processing and digital filtering of signals. Results and discussions. Experimental data obtained during machining made it possible to determine that an increase in the angle of inclination of a single-edge cutting tool has practically no effect on the change in the amplitude parameters of roughness. The values of vibroacoustic diagnostics and roughness, when using a double-edge ball-end tool, show a consistent picture with the effects created by the angles of inclination and advance. The obtained solutions to the problems of monitoring and analyzing the roughness parameters can significantly reduce the amount of experimental research and clarify the idea of the practical implementation of the method of acoustic monitoring of the cutting process.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44888123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-15DOI: 10.17212/1994-6309-2023-25.1-71-84
Yuriy Podgornyj, A. Kirillov, V Yu Skeeba, T. Martynova, D. Lobanov, N. Martyushev
Introduction. Existing mixing devices operate at a constant angular velocity of the working body. During this process, there are zones in which there may be no movement of material, which leads to a decrease in the quality of the finished product. When the working body moves with a variable angular rate, the inertia forces, when changing its sign, contribute to the creation of conditions under which the mixture will lose contact with the blade and move to new levels of movement, and this helps to improve the quality and intensity of the mixing process. The purpose of the work is to improve the quality of the processed mixture on horizontal blade (kneading) machine. Methods. Theoretical studies are carried out using the basic provisions of the theory of machines and mechanisms, structural and parametric synthesis, kinematic analysis, mathematical and computer simulation. Results and discussion. In accordance with the proposed method, the synthesis of the cam-rocker mechanism is carried out, which made it possible to select the main dimensions for the cam mechanism: the minimum radius and center distance. For the synthesis of the rocker group, the parameters of the synthesized cam mechanism are used and, using the main parameters for the rocker group (the size of the input link, the angle of the second arm initial position and rocker centre line, equal to 90°). The rocker arm span angle is obtained equal to 103°. As a result of the kinematic calculation, it is found that the dwell time of the working shafts is within 80°. The quality of the mixture can be assessed by the angle of the stagnation zone, which is formed during the movement of granular material. Under static conditions, it is equal to 0.846°, and at variable angular rate — 0.550°. It is theoretically confirmed that inertial forces that change sign four times in one cycle will provide shaking and rebound of the mixed mass from the blades, which, in turn, will significantly improve the quality of the mixture.
{"title":"Synthesis of the drive mechanism of the continuous production machine","authors":"Yuriy Podgornyj, A. Kirillov, V Yu Skeeba, T. Martynova, D. Lobanov, N. Martyushev","doi":"10.17212/1994-6309-2023-25.1-71-84","DOIUrl":"https://doi.org/10.17212/1994-6309-2023-25.1-71-84","url":null,"abstract":"Introduction. Existing mixing devices operate at a constant angular velocity of the working body. During this process, there are zones in which there may be no movement of material, which leads to a decrease in the quality of the finished product. When the working body moves with a variable angular rate, the inertia forces, when changing its sign, contribute to the creation of conditions under which the mixture will lose contact with the blade and move to new levels of movement, and this helps to improve the quality and intensity of the mixing process. The purpose of the work is to improve the quality of the processed mixture on horizontal blade (kneading) machine. Methods. Theoretical studies are carried out using the basic provisions of the theory of machines and mechanisms, structural and parametric synthesis, kinematic analysis, mathematical and computer simulation. Results and discussion. In accordance with the proposed method, the synthesis of the cam-rocker mechanism is carried out, which made it possible to select the main dimensions for the cam mechanism: the minimum radius and center distance. For the synthesis of the rocker group, the parameters of the synthesized cam mechanism are used and, using the main parameters for the rocker group (the size of the input link, the angle of the second arm initial position and rocker centre line, equal to 90°). The rocker arm span angle is obtained equal to 103°. As a result of the kinematic calculation, it is found that the dwell time of the working shafts is within 80°. The quality of the mixture can be assessed by the angle of the stagnation zone, which is formed during the movement of granular material. Under static conditions, it is equal to 0.846°, and at variable angular rate — 0.550°. It is theoretically confirmed that inertial forces that change sign four times in one cycle will provide shaking and rebound of the mixed mass from the blades, which, in turn, will significantly improve the quality of the mixture.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45159828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-15DOI: 10.17212/1994-6309-2023-25.1-6-15
S. Ryaboshuk, P. Kovalev
Introdution. Austenitic steel (e.g., AISI 304, AISI 321, AISI 316, AISI 403, 12-Cr18-Ni10-Ti, etc.) is widespread, which is caused by high corrosion resistance and the corresponding possibility of use in aggressive media. The following most common types of 12-Cr18-Ni10-Ti steel defects can be distinguished: integranular corrosion, martensitic orientation of the α-phase and ferrite δ-phase. The purpose of work: to analyze the defects formation reasons of the 12-Cr18-Ni10-Ti steel grade billets and to develop recommendations for their elimination. The methods of investigation. Tests of 12-Cr18-Ni10-Ti steel samples for resistance to integranular corrosion, metallographic analysis of defects were carried out in this work. Hardness measurements were carried out for various degrees of billets reduction. Thermodynamic calculations of phase equilibrium in multicomponent steel for different temperatures were performed by the Thermo-Calc software. Results and Discussion. It is determined that in order to prevent integranular corrosion, it is necessary to reduce the nitrogen and carbon content in steel at the stage of ladle refining to 0.05%, and also to ensure the concentration of titanium in steel is not less than the permissible value — 0.3%. These measures contribute to the reduction of Cr23C6 chromium carbides responsible for integranular corrosion. It is necessary to reduce the degree of compression of the billets to a level of no more than 50% to prevent the appearance of a ferromagnetic martensitic α-phase, since the formation of this defect is associated with a high degree of compression during drawing. The high-temperature phase of δ-ferrite exists in the metal structure in a wide temperature range. Reducing this range to 100 degrees or less by optimizing the composition of the carbon and chromium alloy in accordance with GOST 5632-2014 leads to a significant reduction of the amount of ferrite. However, it is not possible to completely eliminate it from the structure of steel. For all cases, it is necessary to assign austenization of billets in the temperature range of 1,050…1,100 °C.
{"title":"Analysis of the reasons for the formation of defects in the 12-Cr18-Ni10-Ti steel billets and development of recommendations for its elimination","authors":"S. Ryaboshuk, P. Kovalev","doi":"10.17212/1994-6309-2023-25.1-6-15","DOIUrl":"https://doi.org/10.17212/1994-6309-2023-25.1-6-15","url":null,"abstract":"Introdution. Austenitic steel (e.g., AISI 304, AISI 321, AISI 316, AISI 403, 12-Cr18-Ni10-Ti, etc.) is widespread, which is caused by high corrosion resistance and the corresponding possibility of use in aggressive media. The following most common types of 12-Cr18-Ni10-Ti steel defects can be distinguished: integranular corrosion, martensitic orientation of the α-phase and ferrite δ-phase. The purpose of work: to analyze the defects formation reasons of the 12-Cr18-Ni10-Ti steel grade billets and to develop recommendations for their elimination. The methods of investigation. Tests of 12-Cr18-Ni10-Ti steel samples for resistance to integranular corrosion, metallographic analysis of defects were carried out in this work. Hardness measurements were carried out for various degrees of billets reduction. Thermodynamic calculations of phase equilibrium in multicomponent steel for different temperatures were performed by the Thermo-Calc software. Results and Discussion. It is determined that in order to prevent integranular corrosion, it is necessary to reduce the nitrogen and carbon content in steel at the stage of ladle refining to 0.05%, and also to ensure the concentration of titanium in steel is not less than the permissible value — 0.3%. These measures contribute to the reduction of Cr23C6 chromium carbides responsible for integranular corrosion. It is necessary to reduce the degree of compression of the billets to a level of no more than 50% to prevent the appearance of a ferromagnetic martensitic α-phase, since the formation of this defect is associated with a high degree of compression during drawing. The high-temperature phase of δ-ferrite exists in the metal structure in a wide temperature range. Reducing this range to 100 degrees or less by optimizing the composition of the carbon and chromium alloy in accordance with GOST 5632-2014 leads to a significant reduction of the amount of ferrite. However, it is not possible to completely eliminate it from the structure of steel. For all cases, it is necessary to assign austenization of billets in the temperature range of 1,050…1,100 °C.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46279196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-15DOI: 10.17212/1994-6309-2023-25.1-16-43
Victor Lapshin, D. Moiseev
Introduction. In numerous experimental studies of metal cutting processes on metal-cutting equipment, the existence of some optimal processing mode is noted, which was most vividly formulated by A.D. Makarov in his point on the existence of an optimal cutting temperature (processing speed). Here, by the authors from Russia, the emphasis is on the description of the optimality of cutting processes related to the properties of the processed material and the properties of the tool used in this process. However, there is another opinion in the Western scientific literature, which is generally based on the regenerative nature of vibrations in cutting dynamics. Vibration regeneration is associated with the dynamics of the cutting process, which is significantly affected by a lagging argument reflecting the variability of the cut layer. The connection of these two approaches is seen through the analysis of the stability domain of the dynamic cutting system in the parameter space: cutting speeds and tool wear values. Subject. Based on this, the paper considers the question of the relationship between the optimal according to A.D. Makarov the processing mode and the dynamics of the cutting process, including the regeneration of tool vibrations during metal turning. To do this, two research hypotheses are formulated and numerical modeling is performed in order to determine its reliability. Purpose of the work: to consider the position of A.D. Makarov on the existence of an optimal cutting mode, from the point of view of the stability of the dynamics of metal turning. For this purpose, two hypotheses are put forward in the work to be analyzed. The paper investigates: a mathematical model describing the dynamics of vibration oscillations of the cutting wedge tip, taking into account the dynamics of the temperature formed in the contact zone and its influence on the forces that prevent the forming motions of the tool. Research methods: a series of field experiments was carried out on a metalworking equipment using the capabilities of the measuring stand STD.201-1, the purpose of which was to determine the effect of the thermal expansion of metals on the value of the buoyant force. Based on numerical simulation of the initial nonlinear mathematical models, as well as simulation of models linearized in the vicinity of the equilibrium point, an analysis of the stability of the cutting system with variations in the cutting speed and the amount of tool wear along the flank is conducted. The results of the work. The results of field experiments are presented, which showed a significant linear increase in the force pushing out the tool with an increase in temperature in the contact zone of the tool and the workpiece. The results of simulation of the state and the corresponding phase trajectories when the cutting wedge is embedded in the workpiece, as well as the forces decomposed along the axis of deformation of the tool, are presented. The results of modeling the M
{"title":"Determination of the optimal metal processing mode when analyzing the dynamics of cutting control systems","authors":"Victor Lapshin, D. Moiseev","doi":"10.17212/1994-6309-2023-25.1-16-43","DOIUrl":"https://doi.org/10.17212/1994-6309-2023-25.1-16-43","url":null,"abstract":"Introduction. In numerous experimental studies of metal cutting processes on metal-cutting equipment, the existence of some optimal processing mode is noted, which was most vividly formulated by A.D. Makarov in his point on the existence of an optimal cutting temperature (processing speed). Here, by the authors from Russia, the emphasis is on the description of the optimality of cutting processes related to the properties of the processed material and the properties of the tool used in this process. However, there is another opinion in the Western scientific literature, which is generally based on the regenerative nature of vibrations in cutting dynamics. Vibration regeneration is associated with the dynamics of the cutting process, which is significantly affected by a lagging argument reflecting the variability of the cut layer. The connection of these two approaches is seen through the analysis of the stability domain of the dynamic cutting system in the parameter space: cutting speeds and tool wear values. Subject. Based on this, the paper considers the question of the relationship between the optimal according to A.D. Makarov the processing mode and the dynamics of the cutting process, including the regeneration of tool vibrations during metal turning. To do this, two research hypotheses are formulated and numerical modeling is performed in order to determine its reliability. Purpose of the work: to consider the position of A.D. Makarov on the existence of an optimal cutting mode, from the point of view of the stability of the dynamics of metal turning. For this purpose, two hypotheses are put forward in the work to be analyzed. The paper investigates: a mathematical model describing the dynamics of vibration oscillations of the cutting wedge tip, taking into account the dynamics of the temperature formed in the contact zone and its influence on the forces that prevent the forming motions of the tool. Research methods: a series of field experiments was carried out on a metalworking equipment using the capabilities of the measuring stand STD.201-1, the purpose of which was to determine the effect of the thermal expansion of metals on the value of the buoyant force. Based on numerical simulation of the initial nonlinear mathematical models, as well as simulation of models linearized in the vicinity of the equilibrium point, an analysis of the stability of the cutting system with variations in the cutting speed and the amount of tool wear along the flank is conducted. The results of the work. The results of field experiments are presented, which showed a significant linear increase in the force pushing out the tool with an increase in temperature in the contact zone of the tool and the workpiece. The results of simulation of the state and the corresponding phase trajectories when the cutting wedge is embedded in the workpiece, as well as the forces decomposed along the axis of deformation of the tool, are presented. The results of modeling the M","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45771026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-15DOI: 10.17212/1994-6309-2022-24.4-33-52
V. Rubtsov, A. Panfilov, E. Knyazhev, Aleksandra Nikolaeva, A. Cheremnov, A. Gusarova, V. Beloborodov, A. Chumaevskii, A. Ivanov
Introduction. An important area of research in the field of plasma metal cutting is obtaining a metal cut face characterized by minimal roughness and geometric deviations. It is also important to minimize changes in the structure of the metal under the cutting surface caused by the temperature effects of the plasma jet, including the formation of dross. The solution to the problem of obtaining a quality cut is to optimize the parameters of the cutting process. The plasma arc current and voltage, cutting height and cutting speed are considered to be the main parameters that determine cut quality. However, insufficient attention has been paid to the processes of plasma metal cutting of thicknesses above 20 mm due to the limitations associated with the operation conditions of plasma torches with direct polarity currents. Accordingly, for cutting large thicknesses, the use of a plasma torch operating on currents of reverse polarity seems promising. The aim of this work is to develop the technique of plasma cutting of copper, titanium and aluminum alloy sheets up to 40 mm thick using a plasma torch operating on currents of reverse polarity. Results and discussion. Investigations show that for cutting aluminum alloy (Al 90.9–94.7 %; Cu 3.8–4.9 %; Mg 1.2-1.8 %; Mn 0.3–0.9 %) and titanium alloy (Ti 94.33–97.5 %; Al 1.5–2.5 %; Mn 0.7–2.0 %) it is possible to regulate the cutting speed in a wide range, while for rolled copper (Cu ≥99.96 %) and aluminum alloy with thickness of 40 mm the range of cutting speed regulation is rather narrow. While for aluminum alloy due to excessive precipitation of alloying elements from the solid solution in the heat-affected zone decrease of microhardness is observed, for titanium alloy the microhardness growth due to material hardening is characteristic. Changing the cutting mode parameters allows receiving more homogeneous macrogeometry of a cutting surface, smaller depth of a zone of melting of a material and a heat-affected zone and smaller changes of mechanical properties of a material in a zone of a cut. For the titanium alloy, almost all of the cutting modes used are close to optimum. For alloy aluminum and copper the modes providing the best cutting quality in the considered range of parameters are determined. According to the results of the work it can be concluded that plasma cutting on reverse polarity currents is effective for cutting rolled products of large thicknesses, but the technique requires further development in order to improve the quality of the resulting cut.
{"title":"Development of plasma cutting technique for C1220 copper, AA2024 aluminum alloy, and Ti-1,5Al-1,0Mn titanium alloy using a plasma torch with reverse polarity","authors":"V. Rubtsov, A. Panfilov, E. Knyazhev, Aleksandra Nikolaeva, A. Cheremnov, A. Gusarova, V. Beloborodov, A. Chumaevskii, A. Ivanov","doi":"10.17212/1994-6309-2022-24.4-33-52","DOIUrl":"https://doi.org/10.17212/1994-6309-2022-24.4-33-52","url":null,"abstract":"Introduction. An important area of research in the field of plasma metal cutting is obtaining a metal cut face characterized by minimal roughness and geometric deviations. It is also important to minimize changes in the structure of the metal under the cutting surface caused by the temperature effects of the plasma jet, including the formation of dross. The solution to the problem of obtaining a quality cut is to optimize the parameters of the cutting process. The plasma arc current and voltage, cutting height and cutting speed are considered to be the main parameters that determine cut quality. However, insufficient attention has been paid to the processes of plasma metal cutting of thicknesses above 20 mm due to the limitations associated with the operation conditions of plasma torches with direct polarity currents. Accordingly, for cutting large thicknesses, the use of a plasma torch operating on currents of reverse polarity seems promising. The aim of this work is to develop the technique of plasma cutting of copper, titanium and aluminum alloy sheets up to 40 mm thick using a plasma torch operating on currents of reverse polarity. Results and discussion. Investigations show that for cutting aluminum alloy (Al 90.9–94.7 %; Cu 3.8–4.9 %; Mg 1.2-1.8 %; Mn 0.3–0.9 %) and titanium alloy (Ti 94.33–97.5 %; Al 1.5–2.5 %; Mn 0.7–2.0 %) it is possible to regulate the cutting speed in a wide range, while for rolled copper (Cu ≥99.96 %) and aluminum alloy with thickness of 40 mm the range of cutting speed regulation is rather narrow. While for aluminum alloy due to excessive precipitation of alloying elements from the solid solution in the heat-affected zone decrease of microhardness is observed, for titanium alloy the microhardness growth due to material hardening is characteristic. Changing the cutting mode parameters allows receiving more homogeneous macrogeometry of a cutting surface, smaller depth of a zone of melting of a material and a heat-affected zone and smaller changes of mechanical properties of a material in a zone of a cut. For the titanium alloy, almost all of the cutting modes used are close to optimum. For alloy aluminum and copper the modes providing the best cutting quality in the considered range of parameters are determined. According to the results of the work it can be concluded that plasma cutting on reverse polarity currents is effective for cutting rolled products of large thicknesses, but the technique requires further development in order to improve the quality of the resulting cut.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42779596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-15DOI: 10.17212/1994-6309-2022-24.4-84-97
D. Bataev, R. Goitemirov, P. Bataeva
Introduction. Sea water is an aggressive environment that causes corrosion, erosion, and cavitation when moving at high speeds of steel, cast iron, bronze, or babbit parts that work satisfactorily only with lubrication. In this case, oil stains are often released into the water, which leads to pollution of the water basin. Materials and methods. To study the wear and friction coefficient, the following materials were chosen: pure polyamide P-610 and antifriction materials based on it Maslyanit D and Maslyanit 12. The following metals were used as the material of the counterbody: stainless steel Cr18Ni9Ti, bronze (9 % Al; 2 % Mn), and titanium alloy VT-3. Results and discussion. It is established that the materials of the “maslyanit” group have significantly better wear resistance and antifriction properties than pure polyamide P-610. It is shown that the reason for such properties of Maslyanit D and Maslyanit 12 is the presence of solid and grease lubricants in its compositions, which simultaneously also play the role of a plasticizer. Finely dispersed metal fillers favorably affect the heat rejection from the friction zone and the growth of the crystalline phase of the polymer. A positive effect of iron minium on the friction of Maslyanit 12, which causes the generation of a protective anti-friction film on the working surfaces of the friction pair, is revealed. A decrease in wear and friction coefficient is found as the purity class of the metal surface increased. The predominantly fatigue mechanism of wear of polymeric materials during friction in a sea water simulator is confirmed. The results of testing Maslyanite 12 in a real marine environment confirmed the positive characteristics of Maslyanit 12.
{"title":"Studies of wear resistance and antifriction properties of metal-polymer pairs operating in a sea water simulator","authors":"D. Bataev, R. Goitemirov, P. Bataeva","doi":"10.17212/1994-6309-2022-24.4-84-97","DOIUrl":"https://doi.org/10.17212/1994-6309-2022-24.4-84-97","url":null,"abstract":"Introduction. Sea water is an aggressive environment that causes corrosion, erosion, and cavitation when moving at high speeds of steel, cast iron, bronze, or babbit parts that work satisfactorily only with lubrication. In this case, oil stains are often released into the water, which leads to pollution of the water basin. Materials and methods. To study the wear and friction coefficient, the following materials were chosen: pure polyamide P-610 and antifriction materials based on it Maslyanit D and Maslyanit 12. The following metals were used as the material of the counterbody: stainless steel Cr18Ni9Ti, bronze (9 % Al; 2 % Mn), and titanium alloy VT-3. Results and discussion. It is established that the materials of the “maslyanit” group have significantly better wear resistance and antifriction properties than pure polyamide P-610. It is shown that the reason for such properties of Maslyanit D and Maslyanit 12 is the presence of solid and grease lubricants in its compositions, which simultaneously also play the role of a plasticizer. Finely dispersed metal fillers favorably affect the heat rejection from the friction zone and the growth of the crystalline phase of the polymer. A positive effect of iron minium on the friction of Maslyanit 12, which causes the generation of a protective anti-friction film on the working surfaces of the friction pair, is revealed. A decrease in wear and friction coefficient is found as the purity class of the metal surface increased. The predominantly fatigue mechanism of wear of polymeric materials during friction in a sea water simulator is confirmed. The results of testing Maslyanite 12 in a real marine environment confirmed the positive characteristics of Maslyanit 12.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49070678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-12-15DOI: 10.17212/1994-6309-2022-24.4-53-63
A. Amirov, E. Moskvichev, A. Ivanov, A. Chumaevskii, V. Beloborodov
Introduction. The technological process of fabrication products from titanium alloys is often complicated by low quality of welded joints during electric arc or gas-flame welding operations due to high residual stresses and deformations. An example of a successful solution to this problem is the development and implementation of such high-tech processes of metal joining as friction stir welding, which does not refer to the methods of fusion joining. Friction stir welding as an advanced technology is used to obtain joints of “soft” metallic materials, such as aluminum. For “hard” metallic materials, friction stir welding has been limited due to the high demands on welding tools. The aim of this work is investigation of the possibility of using a tool made of the nickel-based heat-resistant alloy ZhS6U in friction stir welding of the titanium alloy Ti-5Al-3Mo-1V. Results and discussion. Optical and scanning electron microscopy results revealed that the structure of the weld is typical of this type of welding, gradient, consisting of a heat-affected zone, thermo-mechanical affected zone and a stir zone with a fragmented structure. When varying welding parameters, it is shown that the defectiveness of the weld is affected to a greater extent by the axial load on the tool, which is caused by a significant difference in the thermal effect on the material. Metallographic analysis methods revealed dissolution of welding tool material fragments in the stir zone of the non-detachable joint. Fractographic analysis of the fracture surface shows that the fracture in the weld zone is ductile, although in this case there are brittle bridges. Varying the parameters of friction stir welding made it possible to obtain an indissoluble joint with at least 90 % of the strength of the base metal.
{"title":"Formation features of a welding joint of alloy Ti-5Al-3Mo-1V by the friction stir welding using heat-resistant tool from ZhS6 alloy","authors":"A. Amirov, E. Moskvichev, A. Ivanov, A. Chumaevskii, V. Beloborodov","doi":"10.17212/1994-6309-2022-24.4-53-63","DOIUrl":"https://doi.org/10.17212/1994-6309-2022-24.4-53-63","url":null,"abstract":"Introduction. The technological process of fabrication products from titanium alloys is often complicated by low quality of welded joints during electric arc or gas-flame welding operations due to high residual stresses and deformations. An example of a successful solution to this problem is the development and implementation of such high-tech processes of metal joining as friction stir welding, which does not refer to the methods of fusion joining. Friction stir welding as an advanced technology is used to obtain joints of “soft” metallic materials, such as aluminum. For “hard” metallic materials, friction stir welding has been limited due to the high demands on welding tools. The aim of this work is investigation of the possibility of using a tool made of the nickel-based heat-resistant alloy ZhS6U in friction stir welding of the titanium alloy Ti-5Al-3Mo-1V. Results and discussion. Optical and scanning electron microscopy results revealed that the structure of the weld is typical of this type of welding, gradient, consisting of a heat-affected zone, thermo-mechanical affected zone and a stir zone with a fragmented structure. When varying welding parameters, it is shown that the defectiveness of the weld is affected to a greater extent by the axial load on the tool, which is caused by a significant difference in the thermal effect on the material. Metallographic analysis methods revealed dissolution of welding tool material fragments in the stir zone of the non-detachable joint. Fractographic analysis of the fracture surface shows that the fracture in the weld zone is ductile, although in this case there are brittle bridges. Varying the parameters of friction stir welding made it possible to obtain an indissoluble joint with at least 90 % of the strength of the base metal.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":"1 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41822025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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