Pub Date : 2021-12-13DOI: 10.17212/1994-6309-2021-23.4-65-78
S. Vasiliev, V. Alekseev, A. Fedorova, D. Lobanov
Introduction. The technology of investigation of screw propellers complex surfaces, which include the marine and aircraft propellers of vehicles, mechatronic profilers for the implementation of reverse engineering, is considered. A review of the scientific literature shows that at present the problem of monitoring complex surfaces of products at various stages of its life cycle requires further research, since the use of available devices and methods does not always provide the necessary accuracy, technological effectiveness and sufficient information on measurements. The purpose of the work is to develop a new technology for studying complex surfaces of propellers, which include marine and aircraft propellers of vehicles by means of a mechatronic profilograph to implement reverse engineering. Methods. The paper considers the implementation of the innovative technology for studying complex surfaces of propellers using the developed mechatronic profilograph. This ingenious mechatronic profilograph is designed to measure the profile and study the shape of complex surfaces of various products, as well as to determine the geometric and morphological parameters of these surfaces. On the basis of theoretical studies the main design and technological parameters are found and the hyperbolic dependence of the angular rate of the laser sensor movement on the scanning radius is determined for the developed mechatronic profilograph. For example, if a constant pitch of the trajectory along the Archimedes spiral is 2 mm, the value of the sensor angular rate should gradually decrease from the maximum value of 2 rad/s to the minimum value of 0.574 rad/s, i.e. by 3.484 times. Results and discussion. It is revealed that the use of cylindrical coordinates for processing the obtained data by a profilograph is logical and has a number of advantages. An express analysis of the propeller surfaces with rotary symmetry is carried out and differences in the shapes of the surfaces of the propeller blades by deviation values in the longitudinal and transverse directions for different radii are established. On the basis of the experimental data, a two-factor power model describing deviations with a determination coefficient of 0.967 is obtained, according to its analysis, it is clear that on average the angle of deviation in the perpendicular direction to the radius - increases from 0 to 0.3, and the angle of deviation along the radius increases from 0 to 5.4.
{"title":"Investigation of complex surfaces of propellers of vehicles by a mechatronic profilograph","authors":"S. Vasiliev, V. Alekseev, A. Fedorova, D. Lobanov","doi":"10.17212/1994-6309-2021-23.4-65-78","DOIUrl":"https://doi.org/10.17212/1994-6309-2021-23.4-65-78","url":null,"abstract":"Introduction. The technology of investigation of screw propellers complex surfaces, which include the marine and aircraft propellers of vehicles, mechatronic profilers for the implementation of reverse engineering, is considered. A review of the scientific literature shows that at present the problem of monitoring complex surfaces of products at various stages of its life cycle requires further research, since the use of available devices and methods does not always provide the necessary accuracy, technological effectiveness and sufficient information on measurements. The purpose of the work is to develop a new technology for studying complex surfaces of propellers, which include marine and aircraft propellers of vehicles by means of a mechatronic profilograph to implement reverse engineering. Methods. The paper considers the implementation of the innovative technology for studying complex surfaces of propellers using the developed mechatronic profilograph. This ingenious mechatronic profilograph is designed to measure the profile and study the shape of complex surfaces of various products, as well as to determine the geometric and morphological parameters of these surfaces. On the basis of theoretical studies the main design and technological parameters are found and the hyperbolic dependence of the angular rate of the laser sensor movement on the scanning radius is determined for the developed mechatronic profilograph. For example, if a constant pitch of the trajectory along the Archimedes spiral is 2 mm, the value of the sensor angular rate should gradually decrease from the maximum value of 2 rad/s to the minimum value of 0.574 rad/s, i.e. by 3.484 times. Results and discussion. It is revealed that the use of cylindrical coordinates for processing the obtained data by a profilograph is logical and has a number of advantages. An express analysis of the propeller surfaces with rotary symmetry is carried out and differences in the shapes of the surfaces of the propeller blades by deviation values in the longitudinal and transverse directions for different radii are established. On the basis of the experimental data, a two-factor power model describing deviations with a determination coefficient of 0.967 is obtained, according to its analysis, it is clear that on average the angle of deviation in the perpendicular direction to the radius - increases from 0 to 0.3, and the angle of deviation along the radius increases from 0 to 5.4.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46395203","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 : 2021-12-13DOI: 10.17212/1994-6309-2021-23.4-21-32
Manojkumar V. Sheladiya, S. Acharya, A. Kothari, G. Acharya
Introduction. The world is at the stage of creating an interdisciplinary approach that will be implemented in metallurgical research. The paper formulates the technique of image analysis in the study of processing at different depths from the mold-metal interface. The purpose of the work. Processing of a cast-iron workpiece within the first 3.5 mm of thickness from the mold-metal interface is a serious problem of solid processing. The study of machinability at different depths is a key requirement of the industry for ease of processing. Machinability will determine a number of factors, including tool consumption, workpiece surface quality, energy consumption, etc. The method of investigation. Image analysis is performed to determine the percentage of graphite in etched and non-etched samples. K-means clustering allows to create a new image from a given one with a clear separation of white and black areas by converting a digital image into a binary image using a threshold value for segmentation. The volume fraction of perlite, the volume fraction of graphite and the average size of graphite flakes in microns are used as input variables for the machinability of cast iron. Results and discussion. The output, that is, the segmented image, will be the input function for calculating the workability index using formulas. Thus, microstructural analysis will help predict the workability index of grey cast iron ASTM A48 Class 20. Using this method and the program, based on the microstructure, it is possible to predict in advance the characteristics of the machining of the part, taking into account possible changes in the casting process itself.
介绍世界正处于创建一种将在冶金研究中实施的跨学科方法的阶段。本文阐述了从模具-金属界面不同深度加工研究中的图像分析技术。工作的目的。在距模具-金属界面的前3.5mm厚度内的铸铁工件的加工是固体加工的严重问题。研究不同深度的可加工性是该行业易于加工的关键要求。可加工性将决定许多因素，包括刀具消耗、工件表面质量、能耗等。调查方法。进行图像分析以确定蚀刻和未蚀刻样品中石墨的百分比。K-means聚类允许通过使用用于分割的阈值将数字图像转换为二进制图像来从给定图像创建具有白色和黑色区域的清晰分离的新图像。珍珠岩的体积分数、石墨的体积分数和以微米为单位的石墨薄片的平均尺寸被用作铸铁可加工性的输入变量。结果和讨论。输出，即分割图像，将是用于使用公式计算可加工性指数的输入函数。因此，微观结构分析将有助于预测灰口铸铁ASTM A48 Class 20的可加工性指数。使用这种方法和程序，可以根据微观结构，在考虑铸造过程本身可能发生的变化的情况下，提前预测零件的加工特性。
{"title":"Application of digital image processing technique in the microstructure analysis and the machinability investigation","authors":"Manojkumar V. Sheladiya, S. Acharya, A. Kothari, G. Acharya","doi":"10.17212/1994-6309-2021-23.4-21-32","DOIUrl":"https://doi.org/10.17212/1994-6309-2021-23.4-21-32","url":null,"abstract":"Introduction. The world is at the stage of creating an interdisciplinary approach that will be implemented in metallurgical research. The paper formulates the technique of image analysis in the study of processing at different depths from the mold-metal interface. The purpose of the work. Processing of a cast-iron workpiece within the first 3.5 mm of thickness from the mold-metal interface is a serious problem of solid processing. The study of machinability at different depths is a key requirement of the industry for ease of processing. Machinability will determine a number of factors, including tool consumption, workpiece surface quality, energy consumption, etc. The method of investigation. Image analysis is performed to determine the percentage of graphite in etched and non-etched samples. K-means clustering allows to create a new image from a given one with a clear separation of white and black areas by converting a digital image into a binary image using a threshold value for segmentation. The volume fraction of perlite, the volume fraction of graphite and the average size of graphite flakes in microns are used as input variables for the machinability of cast iron. Results and discussion. The output, that is, the segmented image, will be the input function for calculating the workability index using formulas. Thus, microstructural analysis will help predict the workability index of grey cast iron ASTM A48 Class 20. Using this method and the program, based on the microstructure, it is possible to predict in advance the characteristics of the machining of the part, taking into account possible changes in the casting process itself.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46230649","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 : 2021-12-13DOI: 10.17212/1994-6309-2021-23.4-47-64
A. Kulkarni, S. Chinchanikar, V. Sargade
Introduction. During machining, the resulting temperature has a wider and more critical impact on machining performance. During machining, the power consumption is mainly converted into heat near the cutting edge of the tool. Almost all the work performed during plastic deformation turns into heat. Researchers have put a lot of effort into measuring the cutting temperature during machining, as it significantly affects tool life and overall machining performance. The purpose of the work: to investigate the temperature of the chip-tool interface, taking into account the influence of cutting parameters and the type of tool coating during SS304 turning. The chip-tool interface temperature is measured by changing the cutting speed and feed with a constant cutting depth for uncoated and PVD single-layer TiAlN and multi-layer TiN/TiAlN coated carbide tools. In addition, an attempt is made to develop a model for predicting the temperature of the chip-tool interface using dimensional analysis and ANN simulating to better understand the process. The methods of investigation. Experiments are carried out with varying the cutting speed (140-260 m/min), feed (0.08-0.2 mm/rev) and a constant cutting depth of 1 mm. The chip-tool interface temperature is measured using the tool-work thermocouple principle. The Calibration Setup is designed to establish the relationship between the produced electromotive force (EMF) and the cutting temperature during machining. Statistical dimensional analysis and artificial neural network models have been developed to predict the temperature of the chip-tool interface. Tangential cutting force and chip attributes such as chip width and thickness are also measured depending on the cutting conditions, which is a prerequisite for dimensional analysis simulation. Results and Discussion. A tool made of TiAlN carbide with PVD coating had a lower temperature at the chip-tool interface than a tool with TiN/TiAlN coating. It has been observed that the chip-tool interface temperature increases prominently with the cutting speed, followed by the chip cross-sectional area and the specific cutting pressure. However, a lower cutting force was observed when using a carbide tool with a multi-layer TiN/TiAlN coating, which can be attributed to a lower coefficient of friction created by the front surface of this tool for flowing chips. On the other hand, the greatest cutting force was observed in uncoated carbide tools. It was noticed that the developed models allow predicting the temperature of the chip-tool interface with an absolute error of 5%. However, the lowest average absolute error of 0.78% was observed with the ANN model and, therefore, can be reliably used to predict the chip-tool interface temperature during SS304 turning.
{"title":"Dimensional analysis and ANN simulation of chip-tool interface temperature during turning SS304","authors":"A. Kulkarni, S. Chinchanikar, V. Sargade","doi":"10.17212/1994-6309-2021-23.4-47-64","DOIUrl":"https://doi.org/10.17212/1994-6309-2021-23.4-47-64","url":null,"abstract":"Introduction. During machining, the resulting temperature has a wider and more critical impact on machining performance. During machining, the power consumption is mainly converted into heat near the cutting edge of the tool. Almost all the work performed during plastic deformation turns into heat. Researchers have put a lot of effort into measuring the cutting temperature during machining, as it significantly affects tool life and overall machining performance. The purpose of the work: to investigate the temperature of the chip-tool interface, taking into account the influence of cutting parameters and the type of tool coating during SS304 turning. The chip-tool interface temperature is measured by changing the cutting speed and feed with a constant cutting depth for uncoated and PVD single-layer TiAlN and multi-layer TiN/TiAlN coated carbide tools. In addition, an attempt is made to develop a model for predicting the temperature of the chip-tool interface using dimensional analysis and ANN simulating to better understand the process. The methods of investigation. Experiments are carried out with varying the cutting speed (140-260 m/min), feed (0.08-0.2 mm/rev) and a constant cutting depth of 1 mm. The chip-tool interface temperature is measured using the tool-work thermocouple principle. The Calibration Setup is designed to establish the relationship between the produced electromotive force (EMF) and the cutting temperature during machining. Statistical dimensional analysis and artificial neural network models have been developed to predict the temperature of the chip-tool interface. Tangential cutting force and chip attributes such as chip width and thickness are also measured depending on the cutting conditions, which is a prerequisite for dimensional analysis simulation. Results and Discussion. A tool made of TiAlN carbide with PVD coating had a lower temperature at the chip-tool interface than a tool with TiN/TiAlN coating. It has been observed that the chip-tool interface temperature increases prominently with the cutting speed, followed by the chip cross-sectional area and the specific cutting pressure. However, a lower cutting force was observed when using a carbide tool with a multi-layer TiN/TiAlN coating, which can be attributed to a lower coefficient of friction created by the front surface of this tool for flowing chips. On the other hand, the greatest cutting force was observed in uncoated carbide tools. It was noticed that the developed models allow predicting the temperature of the chip-tool interface with an absolute error of 5%. However, the lowest average absolute error of 0.78% was observed with the ANN model and, therefore, can be reliably used to predict the chip-tool interface temperature during SS304 turning.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48244346","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 : 2021-12-13DOI: 10.17212/1994-6309-2021-23.4-125-139
K. Zakharchenko, V. Kapustin, A. Larichkin
Introduction. The strength of construction materials when used under cyclic loads is of great importance in design engineering. A significant number of factors that affect the fatigue resistance have predetermined the creation of numerous methods that consider such influence. Nondestructive methods that are based on the connection of the physical degradation of material with strain properties enable evaluating experimentally the fatigue properties of materials. Purpose of study: the analysis of the processes of energy dissipation and strain accumulation during the inelastic cyclic strain of samples, using the VT6 (Ti-6Al-4V) titanium alloy and the D16 (Al-Cu-Mg) aluminum alloy before and after the technological impact. The work experimentally investigates the physical processes of degradation of the VT6 and D16 alloy samples that accompany the process of fatigue failure in materials with homogeneous and inhomogeneous stress-strain states in the concentrator (in the form of a hole and a weld). Typical modes are used to reach the fatigue testing that determine the critical stress in a material sample – the stress at which physical properties (temperature, strain) change without reaching the fatigue failure of samples. Critical stress amplitudes in the cycle, based on the data obtained during the experiment and the results of mathematical simulation, are compared. The effect of stress concentrators on critical loads that a detail can withstand after a unit operation is estimated by the finite-element method (FEM). As a result, the effect of the operational and technological factors on critical stress determined by strain and temperature is estimated. Comparative tests of the VT6 and D16 alloy samples with and without stress concentrators showed that the amplitudes of critical stress decrease by more than 30% in comparison with the ones that are without stress concentrators. The low-cycle fatigue tests of the D16 alloy samples are carried out. Mathematical simulation of the cyclic strain of the samples is carried out using MSC.Marc package. The results of the cyclic loading tests, which show that the characteristics of the technological process reduce the amplitudes of the critical stress of the VT6 and D16 alloys and affect the fatigue properties of the D16 aluminum alloy, are discussed. Mathematical simulation corresponded positively to the experimental data. Such correspondence indicates the possibility of conducting qualitative numerical assessments of the beginning of the inelastic strain accumulation process in structures with stress concentrators under the cyclic stress and the increasing stress amplitude, using the typical sample made of hardening elastoplastic material.
{"title":"Enhanced assessment of technological factors for Ti-6Al-4V and Al-Cu-Mg strength properties","authors":"K. Zakharchenko, V. Kapustin, A. Larichkin","doi":"10.17212/1994-6309-2021-23.4-125-139","DOIUrl":"https://doi.org/10.17212/1994-6309-2021-23.4-125-139","url":null,"abstract":"Introduction. The strength of construction materials when used under cyclic loads is of great importance in design engineering. A significant number of factors that affect the fatigue resistance have predetermined the creation of numerous methods that consider such influence. Nondestructive methods that are based on the connection of the physical degradation of material with strain properties enable evaluating experimentally the fatigue properties of materials. Purpose of study: the analysis of the processes of energy dissipation and strain accumulation during the inelastic cyclic strain of samples, using the VT6 (Ti-6Al-4V) titanium alloy and the D16 (Al-Cu-Mg) aluminum alloy before and after the technological impact. The work experimentally investigates the physical processes of degradation of the VT6 and D16 alloy samples that accompany the process of fatigue failure in materials with homogeneous and inhomogeneous stress-strain states in the concentrator (in the form of a hole and a weld). Typical modes are used to reach the fatigue testing that determine the critical stress in a material sample – the stress at which physical properties (temperature, strain) change without reaching the fatigue failure of samples. Critical stress amplitudes in the cycle, based on the data obtained during the experiment and the results of mathematical simulation, are compared. The effect of stress concentrators on critical loads that a detail can withstand after a unit operation is estimated by the finite-element method (FEM). As a result, the effect of the operational and technological factors on critical stress determined by strain and temperature is estimated. Comparative tests of the VT6 and D16 alloy samples with and without stress concentrators showed that the amplitudes of critical stress decrease by more than 30% in comparison with the ones that are without stress concentrators. The low-cycle fatigue tests of the D16 alloy samples are carried out. Mathematical simulation of the cyclic strain of the samples is carried out using MSC.Marc package. The results of the cyclic loading tests, which show that the characteristics of the technological process reduce the amplitudes of the critical stress of the VT6 and D16 alloys and affect the fatigue properties of the D16 aluminum alloy, are discussed. Mathematical simulation corresponded positively to the experimental data. Such correspondence indicates the possibility of conducting qualitative numerical assessments of the beginning of the inelastic strain accumulation process in structures with stress concentrators under the cyclic stress and the increasing stress amplitude, using the typical sample made of hardening elastoplastic material.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48173611","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 : 2021-12-13DOI: 10.17212/1994-6309-2021-23.4-140-154
T. Kalashnikova, V. Beloborodov, K. Osipovich, A. Vorontsov, K. Kalashnikov
Introduction. Friction stir welding and processing are almost identical processes of severe plastic deformation at elevated temperatures. These technologies differ mainly in the purpose of its use: the formation of a hardened surface layer or producing a welded joint. However, it is known that both during welding and during processing of heavy gauge workpieces temperature gradients occur. As a result, the conditions of adhesive interaction, material plastic flow, and the formation of the stir zone change as compared to thin-sheet workpieces with fundamentally different heat dissipation rates. In this connection, the purpose of the work is to determine the regularities of the structure formation and stability of the mechanical properties in different directions in the material of 35-mm-thick aluminum-magnesium alloy samples produced by friction stir welding/processing. Research Methodology. The technique and modes of friction stir welding and processing of AA5056 alloy workpieces with a thickness of 35 mm are described. Data on the equipment used for mechanical tests and structural research are given. Results and discussion. The data obtained show the excess mechanical properties of the processing zone material over the base metal ones in all studied directions. Material structure heterogeneities after friction stir welding/processing of heavy gauge workpieces have no determining effect on the stir zone properties. At the same time, there is no clear correlation between the tensile strength values and the load application direction, nor is there any significant difference in mechanical properties depending on the location of the samples inside the stir zone. The average ultimate tensile strength values in the vertical, transverse, and longitudinal directions are 302, 295 and 303 MPa, respectively, with the yield strength values of 155, 153 and 152 MPa, and the relative elongation of 27.2, 27.5, 28.7 %.
{"title":"Stir zone material flow patterns during friction stir welding of heavy gauge AA5056 workpieces and stability of its mechanical properties","authors":"T. Kalashnikova, V. Beloborodov, K. Osipovich, A. Vorontsov, K. Kalashnikov","doi":"10.17212/1994-6309-2021-23.4-140-154","DOIUrl":"https://doi.org/10.17212/1994-6309-2021-23.4-140-154","url":null,"abstract":"Introduction. Friction stir welding and processing are almost identical processes of severe plastic deformation at elevated temperatures. These technologies differ mainly in the purpose of its use: the formation of a hardened surface layer or producing a welded joint. However, it is known that both during welding and during processing of heavy gauge workpieces temperature gradients occur. As a result, the conditions of adhesive interaction, material plastic flow, and the formation of the stir zone change as compared to thin-sheet workpieces with fundamentally different heat dissipation rates. In this connection, the purpose of the work is to determine the regularities of the structure formation and stability of the mechanical properties in different directions in the material of 35-mm-thick aluminum-magnesium alloy samples produced by friction stir welding/processing. Research Methodology. The technique and modes of friction stir welding and processing of AA5056 alloy workpieces with a thickness of 35 mm are described. Data on the equipment used for mechanical tests and structural research are given. Results and discussion. The data obtained show the excess mechanical properties of the processing zone material over the base metal ones in all studied directions. Material structure heterogeneities after friction stir welding/processing of heavy gauge workpieces have no determining effect on the stir zone properties. At the same time, there is no clear correlation between the tensile strength values and the load application direction, nor is there any significant difference in mechanical properties depending on the location of the samples inside the stir zone. The average ultimate tensile strength values in the vertical, transverse, and longitudinal directions are 302, 295 and 303 MPa, respectively, with the yield strength values of 155, 153 and 152 MPa, and the relative elongation of 27.2, 27.5, 28.7 %.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48975833","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 : 2021-09-15DOI: 10.17212/1994-6309-2021-23.3-100-111
E. Abdulmenova, S. Kulkov
Introduction. Industrial nickel-titanium alloy PN55T45 closed to the equiatomic composition is widely used for the manufacture of products by powder metallurgy. To achieve high physical and mechanical properties of the material obtained by this method, it is necessary to use fine powders, which can be obtained by implementing high-intensity grinding in a planetary ball mill. However, during such treatment, contamination, powder oxidation and particle aggregation, etc. are possible. To solve this problem, preliminary hydrogenation is proposed for subsequent grinding in a planetary ball mill. The aim of the work is to study the effect of hydrogen on the grinding of titanium nickelide powder. Materials and methods. The morphology and average particle size of the powders were studied by scanning electron microscopy. The structure and phase composition of the powders were investigated by the methods of X-ray structural and X-ray phase analysis. The data of X-ray structural analysis were used to estimate the dislocation density. Results and discussions. It is shown that the use of pre-hydrogenation for 180 minutes before machining allows reducing the average particle size by about a half. After mechanical treatment of the powder, the parameters of the crystal lattices of the TiNi (austenite), Ti2Ni and Ni3Ti phases do not change within the error range. After mechanical treatment of the powder with preliminary hydrogenation, the crystal lattice parameter of only the Ti2Ni phase changes significantly, in particular, at 180 minutes of hydrogenation, the lattice parameter increases to 1.1457 ± 5×10-4 nm, which corresponds to the stoichiometry of the Ti2NiH0.5 hydride with a lattice parameter of 1.1500 nm. The highest dislocation density estimated by X-ray diffraction analysis is contained in the Ti2Ni (511) phase than in the TiNi (austenite) (110) and Ni3Ti (202) phases. Thus, preliminary hydrogenation can be an effective method of powder grinding due to the formation of brittle hydride and suppression of the aggregation of fine particles during high-intensity mechanical treatment.
{"title":"Hydrogen and its effect on the grinding of Ti-Ni powder","authors":"E. Abdulmenova, S. Kulkov","doi":"10.17212/1994-6309-2021-23.3-100-111","DOIUrl":"https://doi.org/10.17212/1994-6309-2021-23.3-100-111","url":null,"abstract":"Introduction. Industrial nickel-titanium alloy PN55T45 closed to the equiatomic composition is widely used for the manufacture of products by powder metallurgy. To achieve high physical and mechanical properties of the material obtained by this method, it is necessary to use fine powders, which can be obtained by implementing high-intensity grinding in a planetary ball mill. However, during such treatment, contamination, powder oxidation and particle aggregation, etc. are possible. To solve this problem, preliminary hydrogenation is proposed for subsequent grinding in a planetary ball mill. The aim of the work is to study the effect of hydrogen on the grinding of titanium nickelide powder. Materials and methods. The morphology and average particle size of the powders were studied by scanning electron microscopy. The structure and phase composition of the powders were investigated by the methods of X-ray structural and X-ray phase analysis. The data of X-ray structural analysis were used to estimate the dislocation density. Results and discussions. It is shown that the use of pre-hydrogenation for 180 minutes before machining allows reducing the average particle size by about a half. After mechanical treatment of the powder, the parameters of the crystal lattices of the TiNi (austenite), Ti2Ni and Ni3Ti phases do not change within the error range. After mechanical treatment of the powder with preliminary hydrogenation, the crystal lattice parameter of only the Ti2Ni phase changes significantly, in particular, at 180 minutes of hydrogenation, the lattice parameter increases to 1.1457 ± 5×10-4 nm, which corresponds to the stoichiometry of the Ti2NiH0.5 hydride with a lattice parameter of 1.1500 nm. The highest dislocation density estimated by X-ray diffraction analysis is contained in the Ti2Ni (511) phase than in the TiNi (austenite) (110) and Ni3Ti (202) phases. Thus, preliminary hydrogenation can be an effective method of powder grinding due to the formation of brittle hydride and suppression of the aggregation of fine particles during high-intensity mechanical treatment.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48178231","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 : 2021-09-15DOI: 10.17212/1994-6309-2021-23.3-31-44
S. Bratan, S. Roshchupkin, A. Kharchenko, A. Chasovitina
Introduction. The quality parameters of products, which determine its performance and functionality, are finally formed in the finishing operations, which include the internal grinding process. In this case, the removal of material from the rough surface of the workpiece occurs due to the presence of several simultaneously running random processes of shaping, occurring during the contact of the grinding wheel and the workpiece. A probabilistic theoretical approach is used to simulate grinding operations. However, for determination of radial material removal and thickness of layer with current roughness, the known models cannot be used, as it does not allow taking into account specific features of machining products made of brittle non-metallic materials. Purpose of the work. Creation of a new theoretical and probabilistic model allowing to calculate radial material removal and layer thickness, in which current roughness is distributed during grinding of brittle non-metallic materials. The aim is to investigate the regularities of brittle non-metallic material particles removal by radial removal and study the current (for the moment) roughness formed after every radial removal in the contact area. In the work, radial material removal and the layer with current roughness are determined by grinding modes, tool surface condition, workpiece and wheel dimensions, and the initial condition of the machined surface after the previous contact. The research methods are mathematical and physical simulation using basic probability theory, distribution laws of random variables, as well as the theory of cutting and the theory of deformable solids. Results and discussion. The developed mathematical models make it possible to trace the dimensions and shape of the contact zone when grinding holes in billets made of silicon, which are somewhat different from those known when machining billets made of metal. The proposed dependencies show that with an increase in the depth of micro-cutting, the radial material removal and the thickness of the layer with the current surface roughness increase for all values of wheel speed and workpiece speed. From the experimental values obtained, the maximum micro-cutting depth and the thickness of the layer with current surface roughness are calculated. The thickness of the said layer is compared with the experimental values obtained from the ground surface profilographs. A comparison of the calculated and experimental data indicates its compliance with almost all feed values, which confirms the adequacy of the obtained equations, which model the real process of grinding holes made of brittle non-metallic materials quite well.
{"title":"Calculation of radial material removal and the thickness of the layer with the current roughness when grinding brittle non-metallic materials","authors":"S. Bratan, S. Roshchupkin, A. Kharchenko, A. Chasovitina","doi":"10.17212/1994-6309-2021-23.3-31-44","DOIUrl":"https://doi.org/10.17212/1994-6309-2021-23.3-31-44","url":null,"abstract":"Introduction. The quality parameters of products, which determine its performance and functionality, are finally formed in the finishing operations, which include the internal grinding process. In this case, the removal of material from the rough surface of the workpiece occurs due to the presence of several simultaneously running random processes of shaping, occurring during the contact of the grinding wheel and the workpiece. A probabilistic theoretical approach is used to simulate grinding operations. However, for determination of radial material removal and thickness of layer with current roughness, the known models cannot be used, as it does not allow taking into account specific features of machining products made of brittle non-metallic materials. Purpose of the work. Creation of a new theoretical and probabilistic model allowing to calculate radial material removal and layer thickness, in which current roughness is distributed during grinding of brittle non-metallic materials. The aim is to investigate the regularities of brittle non-metallic material particles removal by radial removal and study the current (for the moment) roughness formed after every radial removal in the contact area. In the work, radial material removal and the layer with current roughness are determined by grinding modes, tool surface condition, workpiece and wheel dimensions, and the initial condition of the machined surface after the previous contact. The research methods are mathematical and physical simulation using basic probability theory, distribution laws of random variables, as well as the theory of cutting and the theory of deformable solids. Results and discussion. The developed mathematical models make it possible to trace the dimensions and shape of the contact zone when grinding holes in billets made of silicon, which are somewhat different from those known when machining billets made of metal. The proposed dependencies show that with an increase in the depth of micro-cutting, the radial material removal and the thickness of the layer with the current surface roughness increase for all values of wheel speed and workpiece speed. From the experimental values obtained, the maximum micro-cutting depth and the thickness of the layer with current surface roughness are calculated. The thickness of the said layer is compared with the experimental values obtained from the ground surface profilographs. A comparison of the calculated and experimental data indicates its compliance with almost all feed values, which confirms the adequacy of the obtained equations, which model the real process of grinding holes made of brittle non-metallic materials quite well.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48499775","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 : 2021-09-15DOI: 10.17212/1994-6309-2021-23.3-124-138
N. Pugacheva, Yu. V. Nikolin, T. Bykova, E. Senaeva
Introduction. The development of new wear-resistant materials obtained by the method of self-propagating high-temperature synthesis (SHS) is an urgent problem in materials science. The SHS method is most widely used in the field of creating new powder materials. Much less attention has been paid to the production of monolithic non-porous composites. For monolithic composites, it is very important to identify the role of the metal matrix and phase transformations in the process of secondary structure formation after the completion of the synthesis process when the obtained material is cooled. The aim of this work was to carry out a comparative analysis of the structure and properties of SHS composites of the Fe-Ti-C-B, Fe-Ni-Ti-C-B, Fe-Ni-Cr-Ti-C-B, and Cu-TiC-B systems. Materials and research methods. Composites were obtained from powder mixtures consisting of thermoreactive components Ti, C, and B, as well as matrix Fe, Fe-Ni, Fe-Ni-Cr, and Cu. The initial powders were thoroughly mixed, loaded into a steel tube container, and the powder mixture was preliminary compacted. Then, the workpieces were heated in an electric furnace to the temperature of the onset of autoignition. After completion of the SHS, the workpieces were deformed with a force of 250 MPa in a hydraulic press at a temperature not lower than 1000 ° C. Samples were cut from the obtained sandwich plates for microstructural studies, density determination, hardness measurements, transverse bending tests and abrasive wear resistance tests. Results and discussion. All investigated composites were characterized by an uneven distribution of strengthening particles TiC and TiB2 over the volume. The use of the Fe-Ni matrix led to the formation of regions with the γ-Fe + Fe2B eutectic structure in the composite and an additional strengthening phase Ni3Ti. The use of Fe-Ni-Cr metal-matrix components led to the formation of two solid solutions in the matrix - austenite and ferrite, and Cr23C6 particles were formed along the boundaries of austenite grains. The maximum transverse bending strength was shown by SHS composites of the Fe-Ti-C-B and Cu-Ti-C-B systems with a matrix of FCC solid solutions. All composites had a hardness of 66 -72 HRC and showed the same abrasion resistance.
{"title":"Influence of the chemical composition of the matrix on the structure and properties of monolithic SHS composites","authors":"N. Pugacheva, Yu. V. Nikolin, T. Bykova, E. Senaeva","doi":"10.17212/1994-6309-2021-23.3-124-138","DOIUrl":"https://doi.org/10.17212/1994-6309-2021-23.3-124-138","url":null,"abstract":"Introduction. The development of new wear-resistant materials obtained by the method of self-propagating high-temperature synthesis (SHS) is an urgent problem in materials science. The SHS method is most widely used in the field of creating new powder materials. Much less attention has been paid to the production of monolithic non-porous composites. For monolithic composites, it is very important to identify the role of the metal matrix and phase transformations in the process of secondary structure formation after the completion of the synthesis process when the obtained material is cooled. The aim of this work was to carry out a comparative analysis of the structure and properties of SHS composites of the Fe-Ti-C-B, Fe-Ni-Ti-C-B, Fe-Ni-Cr-Ti-C-B, and Cu-TiC-B systems. Materials and research methods. Composites were obtained from powder mixtures consisting of thermoreactive components Ti, C, and B, as well as matrix Fe, Fe-Ni, Fe-Ni-Cr, and Cu. The initial powders were thoroughly mixed, loaded into a steel tube container, and the powder mixture was preliminary compacted. Then, the workpieces were heated in an electric furnace to the temperature of the onset of autoignition. After completion of the SHS, the workpieces were deformed with a force of 250 MPa in a hydraulic press at a temperature not lower than 1000 ° C. Samples were cut from the obtained sandwich plates for microstructural studies, density determination, hardness measurements, transverse bending tests and abrasive wear resistance tests. Results and discussion. All investigated composites were characterized by an uneven distribution of strengthening particles TiC and TiB2 over the volume. The use of the Fe-Ni matrix led to the formation of regions with the γ-Fe + Fe2B eutectic structure in the composite and an additional strengthening phase Ni3Ti. The use of Fe-Ni-Cr metal-matrix components led to the formation of two solid solutions in the matrix - austenite and ferrite, and Cr23C6 particles were formed along the boundaries of austenite grains. The maximum transverse bending strength was shown by SHS composites of the Fe-Ti-C-B and Cu-Ti-C-B systems with a matrix of FCC solid solutions. All composites had a hardness of 66 -72 HRC and showed the same abrasion resistance.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49111458","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 : 2021-09-15DOI: 10.17212/1994-6309-2021-23.3-139-154
I. Banshchikova
Introduction. Reducing the level of damage accumulation during pressure treatment of materials at elevated temperatures in creep and close to superplasticity modes in the manufacture of parts can significantly increase its service life in the cold state. Finding temperature and power conditions leading to a reduction in damage of material during the production process and operation is an important task. The purposes of the work: 1) to show the possibility of using the Sosnin-Gorev creep and damage model for alloys with a non-monotonic dependence of strain at fracture on diagrams with creep curves; 2) to carry out comparative analysis of damage accumulation under conditions of uniaxial tension at constant stress and at constant strain rates for alloy with such a dependence. Research methods. Used scalar damage parameter is equated to the normalized deformation, i.e. to the ratio of the current strain to the fracture strain. To find the coefficients of relations creep and damage, the similarity of the creep curves in the normalized values “normalized strain – normalized time”, i.e. the presence of single normalized curve of damage accumulation is checked. The least squares method is used to approximate the experimental data. Numerical integration methods are used for comparative analysis of deformation modes. Results and discussion. Determination of the parameters of the creep and damage equations by the method of a single normalized curve is carried out on the example of experimental data for steel 12Kh18N10T (12Cr18Ni10Ti) at 850 °C, which has a minimum of fracture strain in diagrams with creep curves. Analysis of the static and kinematic modes of deformation for studied material showed that damage accumulation in both cases is practically the same for stresses close to the stress at which this minimum is reached. If the stresses are lower, then the lower level of damage accumulation will be in the kinematic mode; if the stresses above the minimum value, then the static mode will lead to a lower level of damage accumulation. Application. The obtained results can be useful when choosing rational modes of forming structural elements from alloys with a non-monotonic dependence of the fracture strain on stress, as well as in evaluating it for long-term strength during operation.
{"title":"Kinetic equations of creep and damage for description of materials with non-monotonic dependence of fracture strain on stress","authors":"I. Banshchikova","doi":"10.17212/1994-6309-2021-23.3-139-154","DOIUrl":"https://doi.org/10.17212/1994-6309-2021-23.3-139-154","url":null,"abstract":"Introduction. Reducing the level of damage accumulation during pressure treatment of materials at elevated temperatures in creep and close to superplasticity modes in the manufacture of parts can significantly increase its service life in the cold state. Finding temperature and power conditions leading to a reduction in damage of material during the production process and operation is an important task. The purposes of the work: 1) to show the possibility of using the Sosnin-Gorev creep and damage model for alloys with a non-monotonic dependence of strain at fracture on diagrams with creep curves; 2) to carry out comparative analysis of damage accumulation under conditions of uniaxial tension at constant stress and at constant strain rates for alloy with such a dependence. Research methods. Used scalar damage parameter is equated to the normalized deformation, i.e. to the ratio of the current strain to the fracture strain. To find the coefficients of relations creep and damage, the similarity of the creep curves in the normalized values “normalized strain – normalized time”, i.e. the presence of single normalized curve of damage accumulation is checked. The least squares method is used to approximate the experimental data. Numerical integration methods are used for comparative analysis of deformation modes. Results and discussion. Determination of the parameters of the creep and damage equations by the method of a single normalized curve is carried out on the example of experimental data for steel 12Kh18N10T (12Cr18Ni10Ti) at 850 °C, which has a minimum of fracture strain in diagrams with creep curves. Analysis of the static and kinematic modes of deformation for studied material showed that damage accumulation in both cases is practically the same for stresses close to the stress at which this minimum is reached. If the stresses are lower, then the lower level of damage accumulation will be in the kinematic mode; if the stresses above the minimum value, then the static mode will lead to a lower level of damage accumulation. Application. The obtained results can be useful when choosing rational modes of forming structural elements from alloys with a non-monotonic dependence of the fracture strain on stress, as well as in evaluating it for long-term strength during operation.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":" ","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45242295","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 : 2021-09-15DOI: 10.17212/1994-6309-2021-23.3-155-165
A. Korolev, S. Sergeichenko, K. Timofeev, G. Maltsev, R. Voinkov
Introduction. The paper is devoted to the creation of an environmentally safe, technologically efficient and cost-effective high-performance integrated scheme for the recycling of lead-containing industrial products and waste, in particular, bismuth oxides and drosses formed during the melting of copper-electrolyte sludge, with the production of commodity monoelement products. To solve the problem, a combined technology is used, which is based on hydrometallurgical operations that allow separating chemical elements with similar properties with high extraction into finished products. The aim of the work is to study and develop fundamental approaches and rational integrated technologies for recycling bismuth drosses and oxides-industrial products of refining rough lead, using reducing melts of raw materials and bismuth-enriched sludge, electrolysis of bismuth lead to obtain rough bismuth containing ≥ 90 % Bi with its direct extraction of ≥ 70 %. Methods and approaches: melting at a temperature of 1,100…1,150 oC a charge of optimal composition containing bismuth oxides, sodium carbonate, silicon dioxide and carbon. Novelty: a decrease in the content of noble metals and accompanying chalcogenes in secondary copper-containing raw materials with an increase in the amount of impurity elements. Results and discussion: joint melting (1,100…1,150 °C) of bismuth oxides, sodium carbonate, silicon dioxide and carbon, taken in the mass ratio 100 : (15‒66) : (11‒25) : (5‒7), allows to transfer 89.0 – 93.6 % of bismuth and 99.5 ‒ 99.7 % of lead from the initial oxides to bismuth lead containing ~7 % Bi and ~80 % Pb. The main phase of the Pb-Bi alloy is elemental lead. The increased flux consumption leads to an increase in the amount of recycled silicate slags that are poor in target metals, into which it passes,%: 1.4 Bi; 2 Pb; 47 Zn; 23 Sb; 33 Sn. Main slag phases are following: Na2CaSiO4, Na4Mg2Si3O10, MgO, Pb, ZnS, PbS. The practical relevance is determined by the optimal mode of reducing melting of bismuth oxides (100 %) to obtain lead bismuth, %: 66 Na2CO3, 25 SiO2, 5 C; the process temperature is 1,150 ° C. The presence of impurities makes it necessary to introduce reagent treatment of lead bismuth into the technological scheme for recycling bismuth oxides. Decontamination and alkaline softening will make it possible to obtain a Pb-Bi alloy suitable for pyroelectrometallurgical recycling.
{"title":"Recycling of bismuth oxides","authors":"A. Korolev, S. Sergeichenko, K. Timofeev, G. Maltsev, R. Voinkov","doi":"10.17212/1994-6309-2021-23.3-155-165","DOIUrl":"https://doi.org/10.17212/1994-6309-2021-23.3-155-165","url":null,"abstract":"Introduction. The paper is devoted to the creation of an environmentally safe, technologically efficient and cost-effective high-performance integrated scheme for the recycling of lead-containing industrial products and waste, in particular, bismuth oxides and drosses formed during the melting of copper-electrolyte sludge, with the production of commodity monoelement products. To solve the problem, a combined technology is used, which is based on hydrometallurgical operations that allow separating chemical elements with similar properties with high extraction into finished products. The aim of the work is to study and develop fundamental approaches and rational integrated technologies for recycling bismuth drosses and oxides-industrial products of refining rough lead, using reducing melts of raw materials and bismuth-enriched sludge, electrolysis of bismuth lead to obtain rough bismuth containing ≥ 90 % Bi with its direct extraction of ≥ 70 %. Methods and approaches: melting at a temperature of 1,100…1,150 oC a charge of optimal composition containing bismuth oxides, sodium carbonate, silicon dioxide and carbon. Novelty: a decrease in the content of noble metals and accompanying chalcogenes in secondary copper-containing raw materials with an increase in the amount of impurity elements. Results and discussion: joint melting (1,100…1,150 °C) of bismuth oxides, sodium carbonate, silicon dioxide and carbon, taken in the mass ratio 100 : (15‒66) : (11‒25) : (5‒7), allows to transfer 89.0 – 93.6 % of bismuth and 99.5 ‒ 99.7 % of lead from the initial oxides to bismuth lead containing ~7 % Bi and ~80 % Pb. The main phase of the Pb-Bi alloy is elemental lead. The increased flux consumption leads to an increase in the amount of recycled silicate slags that are poor in target metals, into which it passes,%: 1.4 Bi; 2 Pb; 47 Zn; 23 Sb; 33 Sn. Main slag phases are following: Na2CaSiO4, Na4Mg2Si3O10, MgO, Pb, ZnS, PbS. The practical relevance is determined by the optimal mode of reducing melting of bismuth oxides (100 %) to obtain lead bismuth, %: 66 Na2CO3, 25 SiO2, 5 C; the process temperature is 1,150 ° C. The presence of impurities makes it necessary to introduce reagent treatment of lead bismuth into the technological scheme for recycling bismuth oxides. Decontamination and alkaline softening will make it possible to obtain a Pb-Bi alloy suitable for pyroelectrometallurgical recycling.","PeriodicalId":42889,"journal":{"name":"Obrabotka Metallov-Metal Working and Material Science","volume":"1 1","pages":""},"PeriodicalIF":0.4,"publicationDate":"2021-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41621758","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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