Pub Date : 2024-07-30DOI: 10.1134/s0020168524700286
I. M. Petrova, E. A. Marchenko, M. M. Khrushchov, I. A. Buyanovskii
Abstract
The influence of damage caused by friction and wear on the accumulation of fatigue damage in the near-surface layers of the material of technical systems operating under dynamic loading is studied. A comparison of test data on samples of carbonized steel Cr–Mn–Si under ultrasonic loading in the range of up to 109 cycles with the results of testing samples of steel 45 at a constant frequency of 100 Hz, which simulates conditions during tribological tests for frictional fatigue, shows that, in all characteristic loading frequency ranges, the resulting stresses are of the same type. When assessing the influence of frictional fatigue on the accumulation of damage and the probability of operational failures, the authors proceed from the assumption that the processes of accumulation of structural damage during cyclic and frictional fatigue are similar. Experimental studies on the behavior of friction coefficients and the magnitude of broadening of X-ray lines, which characterizes changes in the dislocation structure of metallic materials (steels and titanium alloys) during friction, as well as frictional fatigue curves, are carried out. It is shown that the process of frictional fatigue failure occurs through the mechanisms of low- and high-cycle fatigue, which can serve as a justification for the proposed approach. As an example, data are given for calculating the probability of compressor failures based on friction fatigue curves over a wide range of loading cycles obtained as a result of tests of the crankshaft neck. The use of these curves makes it possible to evaluate the influence of the combined action of dynamic load and friction resulting in an increase in gaps and dynamic loads during wear of contacting parts on the accumulation of fatigue damage, durability, and reliability during operation.
{"title":"Structural and Functional Regularities of the Damage Accumulation and Failure in Metals under Dynamic Loading and Wear","authors":"I. M. Petrova, E. A. Marchenko, M. M. Khrushchov, I. A. Buyanovskii","doi":"10.1134/s0020168524700286","DOIUrl":"https://doi.org/10.1134/s0020168524700286","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The influence of damage caused by friction and wear on the accumulation of fatigue damage in the near-surface layers of the material of technical systems operating under dynamic loading is studied. A comparison of test data on samples of carbonized steel Cr–Mn–Si under ultrasonic loading in the range of up to 10<sup>9</sup> cycles with the results of testing samples of steel 45 at a constant frequency of 100 Hz, which simulates conditions during tribological tests for frictional fatigue, shows that, in all characteristic loading frequency ranges, the resulting stresses are of the same type. When assessing the influence of frictional fatigue on the accumulation of damage and the probability of operational failures, the authors proceed from the assumption that the processes of accumulation of structural damage during cyclic and frictional fatigue are similar. Experimental studies on the behavior of friction coefficients and the magnitude of broadening of X-ray lines, which characterizes changes in the dislocation structure of metallic materials (steels and titanium alloys) during friction, as well as frictional fatigue curves, are carried out. It is shown that the process of frictional fatigue failure occurs through the mechanisms of low- and high-cycle fatigue, which can serve as a justification for the proposed approach. As an example, data are given for calculating the probability of compressor failures based on friction fatigue curves over a wide range of loading cycles obtained as a result of tests of the crankshaft neck. The use of these curves makes it possible to evaluate the influence of the combined action of dynamic load and friction resulting in an increase in gaps and dynamic loads during wear of contacting parts on the accumulation of fatigue damage, durability, and reliability during operation.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"16 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-30DOI: 10.1134/s0020168524700274
N. A. Makhutov, M. M. Gadenin, O. N. Yudina
Abstract
The main cyclic thermomechanical and relevant time-variable vibration and aero-hydrodynamic loadings affect modern energy facilities and space, air, water, and land transport during their operation. The total number of loading cycles with allowance for the operating time turns out to vary within very wide limits. It has been shown that a general time range of loads affecting the aforementioned objects appears to be very complex in terms of load levels, frequencies, and action times. Taking into account a wide variation of service impacts in the loading level, frequency, and total number of loading cycles, the general analysis of the resistance to deformation, damage, and fracture of highly loaded modern technical objects has been carried out. The results obtained have shown that, under combined mechanical, vibration, and aero-hydrodynamic loadings, the limit state, by the cyclic strength criteria with the use of the rule of linear summation of damage expressed in deformation parameters, will be attained earlier than in the case when only the main thermomechanical loading is taken into account. To substantiate the strength and operating life of the investigated objects, standard and unified mechanical isothermal tests for static and cyclic loading have been performed to determine the basic mechanical properties of a material, and special mechanical programmed tests with variable modes simulating complex operational thermomechanical, vibration, and aero-hydrodynamic impacts have been carried out. The results of these tests are used in the computational and experimental estimations of the strength and durability for the corresponding spectra of operational loads. A refined verification calculation of the cyclic strength and durability is becoming increasingly relevant for modern machines operating under the conditions of increasing speeds of movement, operating pressures with increased levels of pulsation, and accompanying mechanical oscillations, vibrations, and aero-hydroacoustic impacts.
{"title":"Analysis of the Cyclic Strength of Technical Systems under Complex Operating Loading Conditions","authors":"N. A. Makhutov, M. M. Gadenin, O. N. Yudina","doi":"10.1134/s0020168524700274","DOIUrl":"https://doi.org/10.1134/s0020168524700274","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The main cyclic thermomechanical and relevant time-variable vibration and aero-hydrodynamic loadings affect modern energy facilities and space, air, water, and land transport during their operation. The total number of loading cycles with allowance for the operating time turns out to vary within very wide limits. It has been shown that a general time range of loads affecting the aforementioned objects appears to be very complex in terms of load levels, frequencies, and action times. Taking into account a wide variation of service impacts in the loading level, frequency, and total number of loading cycles, the general analysis of the resistance to deformation, damage, and fracture of highly loaded modern technical objects has been carried out. The results obtained have shown that, under combined mechanical, vibration, and aero-hydrodynamic loadings, the limit state, by the cyclic strength criteria with the use of the rule of linear summation of damage expressed in deformation parameters, will be attained earlier than in the case when only the main thermomechanical loading is taken into account. To substantiate the strength and operating life of the investigated objects, standard and unified mechanical isothermal tests for static and cyclic loading have been performed to determine the basic mechanical properties of a material, and special mechanical programmed tests with variable modes simulating complex operational thermomechanical, vibration, and aero-hydrodynamic impacts have been carried out. The results of these tests are used in the computational and experimental estimations of the strength and durability for the corresponding spectra of operational loads. A refined verification calculation of the cyclic strength and durability is becoming increasingly relevant for modern machines operating under the conditions of increasing speeds of movement, operating pressures with increased levels of pulsation, and accompanying mechanical oscillations, vibrations, and aero-hydroacoustic impacts.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"42 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865500","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-30DOI: 10.1134/s0020168524700249
A. M. Pokrovskii, Yu. G. Matvienko, M. P. Egranov
<h3 data-test="abstract-sub-heading">Abstract</h3><p>A methodology for evaluating the durability of plate elements of structures taking into account biaxial constraints of deformations along the front of a normal rupture crack (mode I crack) is presented. The absence of the available published data in which the prediction of the crack growth is carried out using <i>T</i><sub><i>xx</i></sub> and <i>T</i><sub><i>zz</i></sub> stresses which are nonsingular terms in the Williams expansion for stresses at the crack tip is noted. The calculation of the fatigue crack growth rate is based on the Paris equation in which the range of the effective SIF is used instead of the range of the usual stress intensity factor (SIF). In this case, the expression for the effective SIF includes <i>T</i><sub><i>xx</i></sub> and <i>T</i><sub><i>zz</i></sub> stresses in addition to the usual SIF. This approach provides taking into account, for example, the thickness of the plate for predicting the durability, which is impossible when only the SIF and <i>T</i><sub><i>xx</i></sub> stresses are used. The formula for the effective SIF is derived on the basis of the assumption that tangential stresses in the pre-fracture zone are equal to the local strength of the material. In this case, the size of the pre-fracture zone and the local strength of the material are determined taking into account <i>T</i><sub><i>xx</i></sub> and <i>T</i><sub><i>zz</i></sub> stresses. The numerical simulation is based on a proprietary finite element program which allows calculating <i>T</i><sub><i>xx</i></sub> and <i>T</i><sub><i>zz</i></sub> stresses at the front of a through crack in a plate subjected to cyclic uniaxial and biaxial tension. It is shown that nonsingular <i>T</i><sub><i>xx</i></sub> stresses primarily describe the effect of biaxial loading on the survivability, whereas <i>T</i><sub><i>zz</i></sub> stresses describe the effect of the plate thickness on the survivability. It is shown that, with increasing thickness of the plate, the value of the effective SIF increases owing to the increased constraint along the crack front, thus increasing the crack growth rate and decreasing the survivability. With an increase in the stress ratio <i>R</i>, under the condition of a constant stress range, the maximum effective SIF reaches the critical value equal to the fracture toughness much faster, thus reducing the durability. It is shown that, for uniaxial cyclic tension, the durability predicted by the proposed methodology is higher than that in the classical approach, when the conventional SIF is used in the Paris equation. For biaxial cyclic tension of a plate, an increase in stresses directed parallel to the crack banks leads to an increase in crack front constraints and therefore to a decrease in the durability compared to the classical approach. In other words, the classical theory does not always provide a conservative estimate of the durability, which indicates the expediency of using t
{"title":"Prediction of the Durability of a Plate with a Through Crack Taking into Account Biaxial Constraints of Deformations along the Front of a Normal Rupture Crack","authors":"A. M. Pokrovskii, Yu. G. Matvienko, M. P. Egranov","doi":"10.1134/s0020168524700249","DOIUrl":"https://doi.org/10.1134/s0020168524700249","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A methodology for evaluating the durability of plate elements of structures taking into account biaxial constraints of deformations along the front of a normal rupture crack (mode I crack) is presented. The absence of the available published data in which the prediction of the crack growth is carried out using <i>T</i><sub><i>xx</i></sub> and <i>T</i><sub><i>zz</i></sub> stresses which are nonsingular terms in the Williams expansion for stresses at the crack tip is noted. The calculation of the fatigue crack growth rate is based on the Paris equation in which the range of the effective SIF is used instead of the range of the usual stress intensity factor (SIF). In this case, the expression for the effective SIF includes <i>T</i><sub><i>xx</i></sub> and <i>T</i><sub><i>zz</i></sub> stresses in addition to the usual SIF. This approach provides taking into account, for example, the thickness of the plate for predicting the durability, which is impossible when only the SIF and <i>T</i><sub><i>xx</i></sub> stresses are used. The formula for the effective SIF is derived on the basis of the assumption that tangential stresses in the pre-fracture zone are equal to the local strength of the material. In this case, the size of the pre-fracture zone and the local strength of the material are determined taking into account <i>T</i><sub><i>xx</i></sub> and <i>T</i><sub><i>zz</i></sub> stresses. The numerical simulation is based on a proprietary finite element program which allows calculating <i>T</i><sub><i>xx</i></sub> and <i>T</i><sub><i>zz</i></sub> stresses at the front of a through crack in a plate subjected to cyclic uniaxial and biaxial tension. It is shown that nonsingular <i>T</i><sub><i>xx</i></sub> stresses primarily describe the effect of biaxial loading on the survivability, whereas <i>T</i><sub><i>zz</i></sub> stresses describe the effect of the plate thickness on the survivability. It is shown that, with increasing thickness of the plate, the value of the effective SIF increases owing to the increased constraint along the crack front, thus increasing the crack growth rate and decreasing the survivability. With an increase in the stress ratio <i>R</i>, under the condition of a constant stress range, the maximum effective SIF reaches the critical value equal to the fracture toughness much faster, thus reducing the durability. It is shown that, for uniaxial cyclic tension, the durability predicted by the proposed methodology is higher than that in the classical approach, when the conventional SIF is used in the Paris equation. For biaxial cyclic tension of a plate, an increase in stresses directed parallel to the crack banks leads to an increase in crack front constraints and therefore to a decrease in the durability compared to the classical approach. In other words, the classical theory does not always provide a conservative estimate of the durability, which indicates the expediency of using t","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"45 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-30DOI: 10.1134/s0020168524700158
R. K. Vagapov, K. A. Ibatullin, V. V. Yarkovoy
Abstract
Elevated concentrations of corrosive carbon dioxide or hydrogen sulfide in gas and gas condensate both produced and transported through pipelines lead to serious corrosion damage to the internal surfaces of steel infrastructure facilities. The paper presents the results of studying the corrosive effect of the medium flow along the lower component of the gas pipeline, which can exhibit a dynamic, intermittent, or static character. During testing, the effect of both dynamic conditions of the medium flow on the U-shaped cell and static conditions of the permanent impact of the aqueous phase on the pipeline wall during the bubble test was evaluated. Modeling of variable wetting conditions inside the gas pipeline showed that such conditions are typical and occur upon production and transportation of raw gas to the places of gas processing and purification. We have simulated dangerous operational factors that occur inside the gas pipeline: the composition of the aquatic environment, temperature, and the content of corrosive gases. When determining the resistance of steels to local forms of corrosion (pitting, wide and shallow corrosion pits), we revealed that the rate of developing local and general corrosion of steel in aggressive carbon dioxide and hydrogen sulfide conditions can reach 2–3 mm/year. In addition, it has been shown that the use of corrosion inhibitors for protecting the equipment and pipelines of gas facilities can effectively prevent the occurrence of internal corrosion processes. The results obtained can be used in assessing the corrosion activity of operating media and selecting the most proven corrosion inhibitors for pilot testing at gas fields.
摘要 在通过管道生产和运输的天然气和天然气凝析油中，腐蚀性二氧化碳或硫化氢浓度的升高会对钢制基础设施的内表面造成严重的腐蚀破坏。本文介绍了沿天然气管道下部的介质流腐蚀效应的研究结果，介质流可能呈现动态、间歇或静态特征。在测试过程中，评估了介质流对 U 型电池的动态影响，以及水相在气泡测试过程中对管道壁的永久影响。天然气管道内可变湿润条件的建模表明，这种条件是典型的，在生产和运输原料天然气到天然气处理和净化场所时会出现。我们模拟了天然气管道内的危险操作因素：水环境成分、温度和腐蚀性气体含量。在确定钢材对局部腐蚀（点蚀、宽而浅的腐蚀坑）的抗性时，我们发现，在二氧化碳和硫化氢的侵蚀条件下，钢材的局部和整体腐蚀发展速度可达 2-3 毫米/年。此外，研究还表明，使用缓蚀剂保护天然气设施的设备和管道可以有效防止内部腐蚀过程的发生。所获得的结果可用于评估运行介质的腐蚀活性，并选择最行之有效的缓蚀剂在气田进行试点测试。
{"title":"Simulation of the Modes of Medium Flow Movement through a Gas Pipeline during Corrosion Tests","authors":"R. K. Vagapov, K. A. Ibatullin, V. V. Yarkovoy","doi":"10.1134/s0020168524700158","DOIUrl":"https://doi.org/10.1134/s0020168524700158","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Elevated concentrations of corrosive carbon dioxide or hydrogen sulfide in gas and gas condensate both produced and transported through pipelines lead to serious corrosion damage to the internal surfaces of steel infrastructure facilities. The paper presents the results of studying the corrosive effect of the medium flow along the lower component of the gas pipeline, which can exhibit a dynamic, intermittent, or static character. During testing, the effect of both dynamic conditions of the medium flow on the U-shaped cell and static conditions of the permanent impact of the aqueous phase on the pipeline wall during the bubble test was evaluated. Modeling of variable wetting conditions inside the gas pipeline showed that such conditions are typical and occur upon production and transportation of raw gas to the places of gas processing and purification. We have simulated dangerous operational factors that occur inside the gas pipeline: the composition of the aquatic environment, temperature, and the content of corrosive gases. When determining the resistance of steels to local forms of corrosion (pitting, wide and shallow corrosion pits), we revealed that the rate of developing local and general corrosion of steel in aggressive carbon dioxide and hydrogen sulfide conditions can reach 2–3 mm/year. In addition, it has been shown that the use of corrosion inhibitors for protecting the equipment and pipelines of gas facilities can effectively prevent the occurrence of internal corrosion processes. The results obtained can be used in assessing the corrosion activity of operating media and selecting the most proven corrosion inhibitors for pilot testing at gas fields.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"49 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-30DOI: 10.1134/s0020168524700225
V. M. Matyunin, A. Yu. Marchenkov, M. V. Goryachkina, A. Yu. Poroykov, D. A. Zhgut, M. A. Karimbekov, A. A. Pankina
Abstract
The modulus of elasticity is considered a fairly stable physicomechanical characteristic of materials, which is little dependent on their composition and structure. Among the factors influencing the modulus of elasticity, temperature and anisotropy are distinguished. Information about the influence of scale factor on the modulus of elasticity is quite limited and sometimes contradictory. The aim of this study is to investigate the influence of the scale factor on the elastic modulus of steel 45 determined by tension geometrically similar specimens with different initial diameters. The specimens were tested on an Instron 8801 universal testing machine at a deformation rate of 0.1 mm/min at room temperature. Elastic deformations during tension were measured using two methods—with the help of a strain gauge and the digital image correlation method. Both methods showed fairly close results when testing specimens of the same diameter. However, the digital image correlation method allowed for measurements of elastic deformations on specimens with small diameters, where it was not possible to attach a strain gauge. A decrease in the modulus of elasticity with an increase in the initial diameter of the specimen was established. Graphical dependences of the modulus of elasticity on the diameter of the specimen and the area of its cross section were obtained. Possible reasons for the decrease in the modulus of elasticity under the influence of the scale factor are outlined. A decrease in specific surface area and specific surface energy, an increase in the deformable volume, and a decrease in the deformation rate at a constant deformation speed are among the main reasons. The decrease in the modulus of elasticity under the influence of the scale factor should be taken into account in strength calculations and when assessing the residual life of parts and structures with relatively large cross sections and wall thicknesses.
{"title":"Influence of the Scale Factor on the Young’s Modulus of Steel Determined by the Tensile Strength of the Specimens","authors":"V. M. Matyunin, A. Yu. Marchenkov, M. V. Goryachkina, A. Yu. Poroykov, D. A. Zhgut, M. A. Karimbekov, A. A. Pankina","doi":"10.1134/s0020168524700225","DOIUrl":"https://doi.org/10.1134/s0020168524700225","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The modulus of elasticity is considered a fairly stable physicomechanical characteristic of materials, which is little dependent on their composition and structure. Among the factors influencing the modulus of elasticity, temperature and anisotropy are distinguished. Information about the influence of scale factor on the modulus of elasticity is quite limited and sometimes contradictory. The aim of this study is to investigate the influence of the scale factor on the elastic modulus of steel 45 determined by tension geometrically similar specimens with different initial diameters. The specimens were tested on an Instron 8801 universal testing machine at a deformation rate of 0.1 mm/min at room temperature. Elastic deformations during tension were measured using two methods—with the help of a strain gauge and the digital image correlation method. Both methods showed fairly close results when testing specimens of the same diameter. However, the digital image correlation method allowed for measurements of elastic deformations on specimens with small diameters, where it was not possible to attach a strain gauge. A decrease in the modulus of elasticity with an increase in the initial diameter of the specimen was established. Graphical dependences of the modulus of elasticity on the diameter of the specimen and the area of its cross section were obtained. Possible reasons for the decrease in the modulus of elasticity under the influence of the scale factor are outlined. A decrease in specific surface area and specific surface energy, an increase in the deformable volume, and a decrease in the deformation rate at a constant deformation speed are among the main reasons. The decrease in the modulus of elasticity under the influence of the scale factor should be taken into account in strength calculations and when assessing the residual life of parts and structures with relatively large cross sections and wall thicknesses.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"24 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-30DOI: 10.1134/s0020168524700262
A. E. Zorin, A. S. Romantsov
Abstract
The mechanical characteristics of a metal are determined by a combination of three groups of factors: the chemical composition, the structural features, and the deformation ability of the structure, i.e., the ability of elements to relax internal stresses during deformation through dislocation sliding which does not lead to the crack formation and destruction. The possibility of using microindentation to assess the deformation ability of the structure of structural steels with a relatively high ductility is the goal of the study. The theoretical analysis revealed that an increase in the stiffness and a decrease in the plasticity of a metal leads to a change in the deformation model during indentation and, in particular, to the occurrence of deformation effects of various morphologies on the surface near the imprint, which can be indicative of the metal plasticity. Experimental studies performed on pipe steels of various strength and types of structure confirmed that, as the deformation ability of the metal decreases (primarily as a result of deformation hardening), a system of localized shears is formed near the imprint along the lines of action of maximum tangential stresses. A scale for ranking data of localized shears is proposed, and the optimal load value and shape of the indenter which provide gaining maximum information by microindentation are determined. A methodology for assessing the embrittlement of plastic construction steels on the basis of the results of microindentation has been developed, which can form a basis for creating an effective technology of nondestructive evaluation of the metal state.
{"title":"Evaluation of Embrittlement of Construction Steels by Microindentation","authors":"A. E. Zorin, A. S. Romantsov","doi":"10.1134/s0020168524700262","DOIUrl":"https://doi.org/10.1134/s0020168524700262","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The mechanical characteristics of a metal are determined by a combination of three groups of factors: the chemical composition, the structural features, and the deformation ability of the structure, i.e., the ability of elements to relax internal stresses during deformation through dislocation sliding which does not lead to the crack formation and destruction. The possibility of using microindentation to assess the deformation ability of the structure of structural steels with a relatively high ductility is the goal of the study. The theoretical analysis revealed that an increase in the stiffness and a decrease in the plasticity of a metal leads to a change in the deformation model during indentation and, in particular, to the occurrence of deformation effects of various morphologies on the surface near the imprint, which can be indicative of the metal plasticity. Experimental studies performed on pipe steels of various strength and types of structure confirmed that, as the deformation ability of the metal decreases (primarily as a result of deformation hardening), a system of localized shears is formed near the imprint along the lines of action of maximum tangential stresses. A scale for ranking data of localized shears is proposed, and the optimal load value and shape of the indenter which provide gaining maximum information by microindentation are determined. A methodology for assessing the embrittlement of plastic construction steels on the basis of the results of microindentation has been developed, which can form a basis for creating an effective technology of nondestructive evaluation of the metal state.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"29 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-30DOI: 10.1134/s0020168524700304
P. A. Bykov, I. E. Kalashnikov, L. I. Kobeleva, I. V. Katin, R. S. Mikheev
Abstract
The paper deals with the effect of Ti2NbAl intermetallic additives on the friction processes of hot-extruded B83 babbitt specimens. Optical and electron microscopy and energy-dispersive analysis were used. The structure, friction surface, and wear products were studied. Tribological tests were performed under dry sliding friction conditions using a universal testing machine according to an axial loading scheme of a steel sleeve to a disk made of the test material. The values of temperature near the friction zone were recorded during tests. The applications of the material depend on the wear regimes and mechanisms occurring in the tribocontact. Changes in wear regimes and mechanisms were assessed in terms of differences in the behavior of the friction coefficient and temperature, differences in the condition of friction surfaces and wear rates, and products of wear. The results suggest that hot pressing of powder containing the alloy B83 and discrete particles of the high-strength intermetallic phase Ti2NbAl is a promising method for producing composite materials with better tribological properties than the babbitt alloy. The introduction of reinforcing high-modulus particles of intermetallic compounds changed the structure of the material and affected the friction processes in the babbitt alloy, delaying the moment when wear regimes shifted into the zone of more severe friction conditions. A substantial reduction in the wear rate of the produced composite materials compared to the initial alloy makes it possible to predict the increase in the service life of tribounits. These data can help determine and recommend the regimes for increasing the service life of tribounits based on B83 alloy as volumetric liners and plain bearings (or sliding bearings), as well as produce new functionally structured layer compositions having enhanced tribological properties, which are based on structural steels and surface coatings using not only B83 babbitt alloy but also its composite materials.
{"title":"Wear Regimes of Hot-Extruded Babbitt-Based Composites","authors":"P. A. Bykov, I. E. Kalashnikov, L. I. Kobeleva, I. V. Katin, R. S. Mikheev","doi":"10.1134/s0020168524700304","DOIUrl":"https://doi.org/10.1134/s0020168524700304","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The paper deals with the effect of Ti<sub>2</sub>NbAl intermetallic additives on the friction processes of hot-extruded B83 babbitt specimens. Optical and electron microscopy and energy-dispersive analysis were used. The structure, friction surface, and wear products were studied. Tribological tests were performed under dry sliding friction conditions using a universal testing machine according to an axial loading scheme of a steel sleeve to a disk made of the test material. The values of temperature near the friction zone were recorded during tests. The applications of the material depend on the wear regimes and mechanisms occurring in the tribocontact. Changes in wear regimes and mechanisms were assessed in terms of differences in the behavior of the friction coefficient and temperature, differences in the condition of friction surfaces and wear rates, and products of wear. The results suggest that hot pressing of powder containing the alloy B83 and discrete particles of the high-strength intermetallic phase Ti<sub>2</sub>NbAl is a promising method for producing composite materials with better tribological properties than the babbitt alloy. The introduction of reinforcing high-modulus particles of intermetallic compounds changed the structure of the material and affected the friction processes in the babbitt alloy, delaying the moment when wear regimes shifted into the zone of more severe friction conditions. A substantial reduction in the wear rate of the produced composite materials compared to the initial alloy makes it possible to predict the increase in the service life of tribounits. These data can help determine and recommend the regimes for increasing the service life of tribounits based on B83 alloy as volumetric liners and plain bearings (or sliding bearings), as well as produce new functionally structured layer compositions having enhanced tribological properties, which are based on structural steels and surface coatings using not only B83 babbitt alloy but also its composite materials.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"131 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-30DOI: 10.1134/s0020168524700171
A. G. Kazantsev, V. N. Skorobogatykh, E. V. Pogorelov, V. A. Piminov, S. Yu. Korolev
Abstract
Estimates of the reference temperature T0 obtained for the base metal and the weld-seam metal of the Cr–Ni–Mo–V type (shell 200 mm thick) on the basis of statistical modeling by the Monte Carlo method are presented. T0 was determined according to the ASTM E1921 standard taking into account the inhomogeneity of the material. The sample size of the fracture toughness values KJC for T0 modeling was 12, 24, and 70. The Monte Carlo method was used for analysis of the correctness of metal identification (homogeneous/inhomogeneous). It is shown that sampling of 12 samples does not provide a reliable determination of whether the metal is homogeneous or inhomogeneous (incorrect results were obtained in 50% of cases for the base metal and in 37% of cases for the weld-seam metal). When the sample size increased to 24 samples, incorrect results were obtained in 5% of cases. The T0 values with allowance for the material inhomogeneity were determined in two ways: using a screening procedure and proceeding from the actual bimodal representation of the fracture toughness distribution (parameters of the bimodal distribution were determined by the maximum likelihood method). It is shown that both methods give close results for the base and weld-seam metal, the magnitude of the shift toward positive values in the average T0 values determined with allowance for the inhomogeneity being about 22°C. Using the obtained T0 estimates, the lower envelopes of the temperature curves of the fracture toughness are constructed (master curves for 5% failure probability).
{"title":"Determination of the Temperature Dependence of the Fracture Toughness of the Metal of a Thick-Walled Shell Taking into Account the Inhomogeneity of the Material","authors":"A. G. Kazantsev, V. N. Skorobogatykh, E. V. Pogorelov, V. A. Piminov, S. Yu. Korolev","doi":"10.1134/s0020168524700171","DOIUrl":"https://doi.org/10.1134/s0020168524700171","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Estimates of the reference temperature <i>T</i><sub>0</sub> obtained for the base metal and the weld-seam metal of the Cr–Ni–Mo–V type (shell 200 mm thick) on the basis of statistical modeling by the Monte Carlo method are presented. <i>T</i><sub>0</sub> was determined according to the ASTM E1921 standard taking into account the inhomogeneity of the material. The sample size of the fracture toughness values <i>K</i><sub><i>JC</i></sub> for <i>T</i><sub>0</sub> modeling was 12, 24, and 70. The Monte Carlo method was used for analysis of the correctness of metal identification (homogeneous/inhomogeneous). It is shown that sampling of 12 samples does not provide a reliable determination of whether the metal is homogeneous or inhomogeneous (incorrect results were obtained in 50% of cases for the base metal and in 37% of cases for the weld-seam metal). When the sample size increased to 24 samples, incorrect results were obtained in 5% of cases. The <i>T</i><sub>0</sub> values with allowance for the material inhomogeneity were determined in two ways: using a screening procedure and proceeding from the actual bimodal representation of the fracture toughness distribution (parameters of the bimodal distribution were determined by the maximum likelihood method). It is shown that both methods give close results for the base and weld-seam metal, the magnitude of the shift toward positive values in the average <i>T</i><sub>0</sub> values determined with allowance for the inhomogeneity being about 22°C. Using the obtained <i>T</i><sub>0</sub> estimates, the lower envelopes of the temperature curves of the fracture toughness are constructed (master curves for 5% failure probability).</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"1 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-30DOI: 10.1134/s0020168524700146
A. S. Kolyanova
Abstract
Many properties of polycrystalline materials depend on their crystallographic texture, which can be fully described by the orientation distribution function (ODF). The main task of quantitative texture analysis is to reconstruct the ODF from its two-dimensional projections, which are obtained through X-ray or neutron diffraction methods. In this work, the results of ODF reconstruction for materials with low lattice and sample symmetry using the harmonic method are presented. The method is based on expanding the ODF in a Fourier series using three-dimensional symmetric spherical functions. Real functions which are linear combinations of corresponding complex spherical functions were used. A model single-component texture and the texture of a magnesium alloy sample subjected to equal-channel angular pressing were investigated. Both textures exhibit hexagonal lattice symmetry and triclinic sample symmetry. In both cases, the RP-factor values and the error of ODF calculation, used to check the adequacy of the solution, showed good agreement between the calculated and original data. It was also found that the ODF of the magnesium alloy sample contains two texture components ((bar {1})2(bar {1})6)[(bar {1})211] and ((bar {1})2(bar {1})6)[(bar {1})2(bar {1})1] with maximum intensities of 13.81 and 2.23, respectively. The obtained results can be used in texture studies of ceramics, rocks, and other nonmetallic materials with low symmetry.
摘要 多晶材料的许多特性取决于其晶体纹理，而晶体纹理可以用取向分布函数（ODF）来完全描述。定量纹理分析的主要任务是通过 X 射线或中子衍射方法获得的二维投影重建 ODF。在这项工作中，介绍了使用谐波法重建低晶格和样品对称性材料的 ODF 的结果。该方法基于使用三维对称球形函数在傅里叶级数中展开 ODF。所使用的实函数是相应复球面函数的线性组合。研究了单组分纹理模型和镁合金样品在等通道角压下的纹理。两种纹理都具有六方晶格对称性和三菱样品对称性。在这两种情况下，用于检验解决方案是否充分的 RP 因子值和 ODF 计算误差在计算数据和原始数据之间显示出良好的一致性。研究还发现，镁合金样品的ODF包含两个纹理成分（(bar {1})2(bar {1})6）[(bar {1})211]和（(bar {1})2(bar {1})6）[(bar {1})2(bar {1})1]，最大强度分别为13.81和2.23。所得结果可用于陶瓷、岩石和其他对称性较低的非金属材料的纹理研究。
{"title":"Reconstruction of the Orientation Distribution Function for Materials with Low Lattice and Sample Symmetry Using the Harmonic Method","authors":"A. S. Kolyanova","doi":"10.1134/s0020168524700146","DOIUrl":"https://doi.org/10.1134/s0020168524700146","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Many properties of polycrystalline materials depend on their crystallographic texture, which can be fully described by the orientation distribution function (ODF). The main task of quantitative texture analysis is to reconstruct the ODF from its two-dimensional projections, which are obtained through X-ray or neutron diffraction methods. In this work, the results of ODF reconstruction for materials with low lattice and sample symmetry using the harmonic method are presented. The method is based on expanding the ODF in a Fourier series using three-dimensional symmetric spherical functions. Real functions which are linear combinations of corresponding complex spherical functions were used. A model single-component texture and the texture of a magnesium alloy sample subjected to equal-channel angular pressing were investigated. Both textures exhibit hexagonal lattice symmetry and triclinic sample symmetry. In both cases, the <i>RP</i>-factor values and the error of ODF calculation, used to check the adequacy of the solution, showed good agreement between the calculated and original data. It was also found that the ODF of the magnesium alloy sample contains two texture components (<span>(bar {1})</span>2<span>(bar {1})</span>6)[<span>(bar {1})</span>211] and (<span>(bar {1})</span>2<span>(bar {1})</span>6)[<span>(bar {1})</span>2<span>(bar {1})</span>1] with maximum intensities of 13.81 and 2.23, respectively. The obtained results can be used in texture studies of ceramics, rocks, and other nonmetallic materials with low symmetry.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"3 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-07-30DOI: 10.1134/s0020168524700316
A. S. Plotnikov, E. B. Zavoychinskaya
Abstract
A phenomenological approach to the actual problem of determining the inhomogeneous residual stress-strain state in the components of high-tech engineering systems at the stages of their design and operation is presented. The approach is based on physical and mechanical methods of measuring displacements. Current physical models describe the physical regularities of the residual states attributed to changes in the structure by the interaction of defects and dislocations in the field of micro- and meso-stresses. At the same time, there are the problems of the transition to the macrolevel, the construction of multilevel models, and the conversion of these models in engineering practice. In the framework of phenomenological approaches, in the general case, the solution of this problem requires the solution of three-dimensional inverse problems of thermoelasticity. A well-known mechanical method for determining a uniform field of residual elastic stresses recommended by ASTM E837 is described. The method proposed earlier by one of the authors for determining an inhomogeneous (in the plane) field of residual elastic stresses is discussed. A method of the three-dimensional inhomogeneous residual elastic stress-strain state determination based on the experimental determination of the displacement vector components by the method of step-by-step point hole-drilling and data of digital speckle interferometry and digital image correlation is developed. The constitutive relations for the components of the displacement vector are written in the form of Volterra integral operators. The basic operator functions are the functions of four variables, i.e., the coordinates of the cylindrical system (r, θ, z) associated with the hole and the hole depth h. A method for verification of the basic functions is presented. The problem is reduced to the determination of three displacement functions of three variables: hole radius r, h, and z. Numerical simulation of basic functions is carried out. The obtained results are consistent with the known experimental data and calculated values of the deformation on the surface depending on the depth of the hole according to the ASTM E837 standard.
摘要 针对高科技工程系统部件在设计和运行阶段的不均匀残余应力-应变状态的实际问题，介绍了一种现象学方法。该方法基于测量位移的物理和机械方法。当前的物理模型描述了残余状态的物理规律性，这些残余状态归因于微应力和介应力场中缺陷和位错相互作用导致的结构变化。同时，还存在向宏观层面过渡、构建多层次模型以及在工程实践中转换这些模型的问题。在现象学方法的框架内，在一般情况下，该问题的解决需要解决热弹性的三维逆问题。本文介绍了 ASTM E837 推荐的确定残余弹性应力均匀场的著名力学方法。还讨论了其中一位作者早先提出的确定不均匀（平面内）残余弹性应力场的方法。根据逐步点钻孔法对位移矢量分量的实验测定以及数字斑点干涉测量和数字图像相关数据，开发了一种三维非均质残余弹性应力-应变状态测定方法。位移矢量分量的构成关系以 Volterra 积分算子的形式书写。基本算子函数是四个变量的函数，即与孔和孔深 h 相关的圆柱系统坐标 (r, θ, z)。问题简化为确定孔半径 r、h 和 z 这三个变量的三个位移函数。获得的结果与已知的实验数据和根据 ASTM E837 标准计算的孔深度表面变形值一致。
{"title":"On the Features of Inhomogeneous Residual Stress Identification Using the Digital Speckle Interferometry and the Hole-Drilling Method","authors":"A. S. Plotnikov, E. B. Zavoychinskaya","doi":"10.1134/s0020168524700316","DOIUrl":"https://doi.org/10.1134/s0020168524700316","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A phenomenological approach to the actual problem of determining the inhomogeneous residual stress-strain state in the components of high-tech engineering systems at the stages of their design and operation is presented. The approach is based on physical and mechanical methods of measuring displacements. Current physical models describe the physical regularities of the residual states attributed to changes in the structure by the interaction of defects and dislocations in the field of micro- and meso-stresses. At the same time, there are the problems of the transition to the macrolevel, the construction of multilevel models, and the conversion of these models in engineering practice. In the framework of phenomenological approaches, in the general case, the solution of this problem requires the solution of three-dimensional inverse problems of thermoelasticity. A well-known mechanical method for determining a uniform field of residual elastic stresses recommended by ASTM E837 is described. The method proposed earlier by one of the authors for determining an inhomogeneous (in the plane) field of residual elastic stresses is discussed. A method of the three-dimensional inhomogeneous residual elastic stress-strain state determination based on the experimental determination of the displacement vector components by the method of step-by-step point hole-drilling and data of digital speckle interferometry and digital image correlation is developed. The constitutive relations for the components of the displacement vector are written in the form of Volterra integral operators. The basic operator functions are the functions of four variables, i.e., the coordinates of the cylindrical system (<i>r</i>, θ, <i>z</i>) associated with the hole and the hole depth <i>h</i>. A method for verification of the basic functions is presented. The problem is reduced to the determination of three displacement functions of three variables: hole radius <i>r</i>, <i>h</i>, and <i>z</i>. Numerical simulation of basic functions is carried out. The obtained results are consistent with the known experimental data and calculated values of the deformation on the surface depending on the depth of the hole according to the ASTM E837 standard.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"131 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141865399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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