The numerical analysis of stress-strain state of low-alloyed welded steel samples test has been c... more The numerical analysis of stress-strain state of low-alloyed welded steel samples test has been considered. The mechanical heterogeneity has been estimated by the micro hardness test. The stress-strain state analysis is based on the models of linear elasticity, which are described by Lame equations for displacement. In this case the samples are considered as perfect welded samples without any welding defects. The discretization of the system of equations is done through the finite element method, and the numerical realization of the method is performed on collection of free software FEniCS. The defects influence has been estimated by stochastic modelling of viscous crack growth. The data for crack size in weld and heat affected zone was obtain from microscopic observation, and for mechanical properties from microhardness testing. The result obtained shows that, the distribution of displacement in all samples are almost the same. Between the welded zone, the heat affected zone and th...
The heterogeneity of manual arc welded samples of low-carbon steel St3sp meant for bridge constru... more The heterogeneity of manual arc welded samples of low-carbon steel St3sp meant for bridge construction to be used in Cameroon has been investigated. The chemical analysis of the material was carried out and the arc welding processes used, then the probes were subject to mechanical testing such as tensile test, low-cycle fatigue test, and micro hardness study. A total inclusion of weld defects in the specific welded sample and especially in the cyclic loading specimes has been discovered. Premature fracture was revealed below the plastic limit in some probes during the tension and low-cycle test. A micro structural examination and micro hardness measurements were done in order to determine what exactly could be the reason of this catastrophic failure. The structural analysis revealed the differences in mechanical properties conditioned by phase distribution and carbon content in weld, heat affected zone and base metal. To determine the heterogeneity in mechanical properties the elast...
RUDENKO INTERNATIONAL CONFERENCE “METHODOLOGICAL PROBLEMS IN RELIABILITY STUDY OF LARGE ENERGY SYSTEMS” (RSES 2021)
The paper discusses a fundamental framework for developing prospective materials and technologies... more The paper discusses a fundamental framework for developing prospective materials and technologies to ensure the technological advantage in the North and the Arctic as well as the energy and technological safety of the industrial sector in cold climates, the analysis of remote energy systems of the Arctic of Republic of Sakha (Yakutia) is also carried out. Operation of power equipment in harsh climates leads to accelerated wear and tear and demands additional repair and reconstruction costs and stricter safety procedures. Examples are given for the application of new metal and composite materials with enhanced cold resistance and production of welding joints. A possibility is discussed for speeding up and enhancing construction reliability in the permafrost zone, reducing risks and improving human protection in developing mining and processing industries, including oil and gas production, based on the following: digitization, artificial intelligence, big and small data analysis, quantum approaches to devising and implementing ecofriendly technologies and enterprises, renewable and efficient energy and access to transport.
Для оценки влияния термического цикла сварки на свойства зоны термического влияния исследована ми... more Для оценки влияния термического цикла сварки на свойства зоны термического влияния исследована микротвердость девяти жестких проб сварных образцов, изготовленных из низколегированной трубной стали 14Х2ГМР, испытанных, и образца из стали Ст3сп, подвергшегося действию усталостного малоциклового нагружения. Было выявлено, что температура внешней среды в диапазоне от-40°C до +20°C практически не влияет на распределение микротвердости в зоне сварки и ЗТВ, несмотря на существенную разницу в скоростях охлаждения. Также исследования показали, что возникающие трещины растут преимущественно вдоль границ зерен мартенсита и бейнита (как перехлаждённого аустенита) в ЗТВ стали 14Х2ГМР, однако могут наблюдаться и трещины, пересекающие тело зерна. В образце из стали Ст3сп холодные трещины наблюдаются как в зоне сварки, так и в ЗТВ, и имеют преимущественно межзеренный характер, даже несмотря на более мягкие по сравнению с принятыми технологическими пробами на трещиностойкость условиями испытания. Ключевые слова: микротвердость, термический цикл сварки, зона термического влияния, рост трещин, граница зерна, модуль упругости. Благодарности: Работа выполнена по программе фундаментальных научных исследований государственных академий наук (проект III.28.1.1.) с использованием оборудования ЦКП «Станция натурных испытаний» ИФТПС СО РАН
The concepts of providing the integrity, reliability and safety of the energy and transport syste... more The concepts of providing the integrity, reliability and safety of the energy and transport systems in the Arctic zone are considered. The inadmissibility of using the concept of acceptable, or tolerable, risk to ensure the operational safety of potentially hazardous facilities used in extreme environment has been validated by the history and reasons of risk analysis reviewing. The new concept for transport and energy systems operating in cold climates has been proposed to include in the security concept flexible information monitoring and control systems that take into account the state of environment, the engineering system and the operator himself. The promptness of implementation of the new concept of renewable development is dictated by the modern transitional state of society from thoughtless consumption of resources to the minimization of environmental damage and the inadmissibility of human casualties, called Industry 5.0.
Abstract The IX Eurasian Symposium on Strength and Service Life at Low Climatic Temperature was h... more Abstract The IX Eurasian Symposium on Strength and Service Life at Low Climatic Temperature was held from 14 to 17 September 2020 in Yakutsk, Republic of Sakha (Yakutia), Russia, and dedicated to 50th anniversary of V.P. Larionov Institute of Physico-Technical Problems of the North, separate subdivision of the Federal Research Center ‘Yakut Scientific Center of Siberian Branch of the Russian Academy of Sciences’. The First Eurasian Symposium on the Problems of Strength of Materials and Machines for Cold Climate Regions was held in Yakutsk on July 16-20, 2002, and gathered more than 370 participants from many Russian scientific institutes and from abroad. The Chairman of the Organizing Committee was Academician of the Russian Academy of Sciences, Doctor of Technical Sciences V.P. Larionov, director of the Institute of Physical-Technical Problems of the North and Chair of the Yakut Scientific Center. This success gave reason to make EURASTRENCOLD Symposium regular. The informational support of the ESIS was provided from 2019 when the First International Conference on Integrity and Lifetime in Extreme Environment (ILEE-2019) held in Yakutsk. The historical aspects and future of research activity in the Republic of Sakha (Yakutia) and Far East, and international scientific collaboration in Europe and Asia has been discussed in the paper.
Abstract Nowadays, the close interaction between the Russian academic science and industry come t... more Abstract Nowadays, the close interaction between the Russian academic science and industry come true by means of The Digital Economics of Russian Federation State Program. It has pass ahead partially of the Industry 4.0 and 5.0 European programs in case of realization of the analysis of development and control methods of the knowledge-intensive complex engineering systems (CES) that are competitive in the world market of high technologies, products, goods and services for the Arctic and the Subarctic. It has been shown how by the using chaos theory and Bayesian principles on the base of multilevel simulation it could be formulated a general scientific and methodological approach to the problem of identifying, analyzing and choosing alternatives for fundamental research area in order to ensure the disruptive development of manufacturing technologies of the CES production for the long term. The methodology for criterion formation of preference, ranking and multi-criteria selection of the most priority alternatives of the fundamental research for Digital Economics, Industry and Society concepts for the Arctic and the Subarctic has been considered.
International Journal of Engineering Technologies and Management Research, 2020
During welding, the heat produced during the process can affect the microhardness and the microst... more During welding, the heat produced during the process can affect the microhardness and the microstructure of the material. The change in the microstructure and the microhardness can be discovered by carrying out a microhardness test on the welded sample and compare changes in the three different zones i.e the base, the weld and the Heat affected zone or by carrying out a micro structural examination on the welded sample and see the grain dispersion in relation to their sizes. In this work, weld quality of manual arc welded samples of low-carbon steel St3spdestined for bridge construction to be used in Cameroon has been investigated. After a chemical analysis of the material, a micro hardness test and a micro structural examination was also done. Results show that a composition of pearlite and ferrite was seen with the print of the id enter of the micro hardness test. The formation of pearlite and ferrite in base metalis composed of 20/80 respectively. For weld zone and HAZ it changes...
The Integrity means not only the structural strength and performance of technical systems. The In... more The Integrity means not only the structural strength and performance of technical systems. The Integrity here is consolidating of the engineers and scientist in many research areas. The extreme environment has a significant influence on infrastructures and living beings during the development and service life in or close to the Arctic regions. Russia has a large boundary to Arctic and has a huge territory classified as a frigid zone. So the extreme environment contains conditions that are hard to survive even for steel structures due to extreme temperature, corrosion, inappropriate service and repair. Many problem should by discussed therefor including the structural integrity as the strength and mechanical properties and behavior of steel, polymer and composite structures, the phase transition processes, inhomogeneity of materials and thermal physics. The transport problem is a very important in Extreme environment, also the energy supply and mining technology. So it is an exigency to discussing and conferencing for the integrity and lifetime in extreme conditions.
The weld joints are characterized by microstructure inhomogeneity and defects due to non-uniform ... more The weld joints are characterized by microstructure inhomogeneity and defects due to non-uniform heating and cooling particularly at service while operating in extremely cold environment. Vickers micro hardness measurement was done on hard probes of welded samples of low-alloyed 14H2GMR and low-carbon St3sp steel. Experimental study was carried out to see the thermal cycling influence on the heat-affected zone properties. It was discovered that, welding at-40°C does not lead to a significant increase of steel micro hardness as compare to welding at +20°C despite the large difference in cooling rates. It was also discovered that, the crack grows mainly along the grain boundaries of martensite and bainite (as over chilled austenite), but in some cases passes through the grain body and cuts across it at 14H2GMR for pipe steel. For structural St2sp steel the inter granular cracks are revealed both in weld metal and in the heat affected zone nevertheless of milder test conditions against hard technological probes.
Abstract Some aspects of damage accumulation modeling and brittle fracture processes mechanisms u... more Abstract Some aspects of damage accumulation modeling and brittle fracture processes mechanisms under the combined effect of mechanical loading and hydrogen has been discussed in the article. New mechanism of brittle fracture for metallic materials based on dislocation and phonon structure fingerprints and lattice hydrogen content under the static and dynamic loading at low temperature condition has been proposed. The mechanism based on theoretical research and experimental and numerical studies. The experiments include the energy spectrum of internal friction determination and impact toughness testing for low-temperature brittle-ductile transition revealing. The numerical study based on damage accumulation modeling under the influence of up-hill diffusion in the elastic-plastic problem of solid state by finite element method. A new simple activation model of low temperature and hydrogen influence on damage accumulation process has been proposed. The model shows the rate of damage strong dependence of stress level and hydrogen content, and test temperature. The combination of low temperature and high hydrogen content is most dangerous, so the weld structures in extreme environment such as the Arctic and Subarctic regions have a high risk of breakage. So it is possible to estimate the energy and phonon spectrum of crystal lattice, and predict the properties of microcrystalline and nanostructured materials with the high cold-short threshold on the base of such the approach. There are the recommendations propose to improve the cold resistance of steels and alloys by controlling the characteristics of the dislocation structure of new materials with polycrystalline and ultrafine-grained structure.
The numerical analysis of stress-strain state of low-alloyed welded steel samples test has been c... more The numerical analysis of stress-strain state of low-alloyed welded steel samples test has been considered. The mechanical heterogeneity has been estimated by the micro hardness test. The stress-strain state analysis is based on the models of linear elasticity, which are described by Lame equations for displacement. In this case the samples are considered as perfect welded samples without any welding defects. The discretization of the system of equations is done through the finite element method, and the numerical realization of the method is performed on collection of free software FEniCS. The defects influence has been estimated by stochastic modelling of viscous crack growth. The data for crack size in weld and heat affected zone was obtain from microscopic observation, and for mechanical properties from microhardness testing. The result obtained shows that, the distribution of displacement in all samples are almost the same. Between the welded zone, the heat affected zone and th...
The heterogeneity of manual arc welded samples of low-carbon steel St3sp meant for bridge constru... more The heterogeneity of manual arc welded samples of low-carbon steel St3sp meant for bridge construction to be used in Cameroon has been investigated. The chemical analysis of the material was carried out and the arc welding processes used, then the probes were subject to mechanical testing such as tensile test, low-cycle fatigue test, and micro hardness study. A total inclusion of weld defects in the specific welded sample and especially in the cyclic loading specimes has been discovered. Premature fracture was revealed below the plastic limit in some probes during the tension and low-cycle test. A micro structural examination and micro hardness measurements were done in order to determine what exactly could be the reason of this catastrophic failure. The structural analysis revealed the differences in mechanical properties conditioned by phase distribution and carbon content in weld, heat affected zone and base metal. To determine the heterogeneity in mechanical properties the elast...
RUDENKO INTERNATIONAL CONFERENCE “METHODOLOGICAL PROBLEMS IN RELIABILITY STUDY OF LARGE ENERGY SYSTEMS” (RSES 2021)
The paper discusses a fundamental framework for developing prospective materials and technologies... more The paper discusses a fundamental framework for developing prospective materials and technologies to ensure the technological advantage in the North and the Arctic as well as the energy and technological safety of the industrial sector in cold climates, the analysis of remote energy systems of the Arctic of Republic of Sakha (Yakutia) is also carried out. Operation of power equipment in harsh climates leads to accelerated wear and tear and demands additional repair and reconstruction costs and stricter safety procedures. Examples are given for the application of new metal and composite materials with enhanced cold resistance and production of welding joints. A possibility is discussed for speeding up and enhancing construction reliability in the permafrost zone, reducing risks and improving human protection in developing mining and processing industries, including oil and gas production, based on the following: digitization, artificial intelligence, big and small data analysis, quantum approaches to devising and implementing ecofriendly technologies and enterprises, renewable and efficient energy and access to transport.
Для оценки влияния термического цикла сварки на свойства зоны термического влияния исследована ми... more Для оценки влияния термического цикла сварки на свойства зоны термического влияния исследована микротвердость девяти жестких проб сварных образцов, изготовленных из низколегированной трубной стали 14Х2ГМР, испытанных, и образца из стали Ст3сп, подвергшегося действию усталостного малоциклового нагружения. Было выявлено, что температура внешней среды в диапазоне от-40°C до +20°C практически не влияет на распределение микротвердости в зоне сварки и ЗТВ, несмотря на существенную разницу в скоростях охлаждения. Также исследования показали, что возникающие трещины растут преимущественно вдоль границ зерен мартенсита и бейнита (как перехлаждённого аустенита) в ЗТВ стали 14Х2ГМР, однако могут наблюдаться и трещины, пересекающие тело зерна. В образце из стали Ст3сп холодные трещины наблюдаются как в зоне сварки, так и в ЗТВ, и имеют преимущественно межзеренный характер, даже несмотря на более мягкие по сравнению с принятыми технологическими пробами на трещиностойкость условиями испытания. Ключевые слова: микротвердость, термический цикл сварки, зона термического влияния, рост трещин, граница зерна, модуль упругости. Благодарности: Работа выполнена по программе фундаментальных научных исследований государственных академий наук (проект III.28.1.1.) с использованием оборудования ЦКП «Станция натурных испытаний» ИФТПС СО РАН
The concepts of providing the integrity, reliability and safety of the energy and transport syste... more The concepts of providing the integrity, reliability and safety of the energy and transport systems in the Arctic zone are considered. The inadmissibility of using the concept of acceptable, or tolerable, risk to ensure the operational safety of potentially hazardous facilities used in extreme environment has been validated by the history and reasons of risk analysis reviewing. The new concept for transport and energy systems operating in cold climates has been proposed to include in the security concept flexible information monitoring and control systems that take into account the state of environment, the engineering system and the operator himself. The promptness of implementation of the new concept of renewable development is dictated by the modern transitional state of society from thoughtless consumption of resources to the minimization of environmental damage and the inadmissibility of human casualties, called Industry 5.0.
Abstract The IX Eurasian Symposium on Strength and Service Life at Low Climatic Temperature was h... more Abstract The IX Eurasian Symposium on Strength and Service Life at Low Climatic Temperature was held from 14 to 17 September 2020 in Yakutsk, Republic of Sakha (Yakutia), Russia, and dedicated to 50th anniversary of V.P. Larionov Institute of Physico-Technical Problems of the North, separate subdivision of the Federal Research Center ‘Yakut Scientific Center of Siberian Branch of the Russian Academy of Sciences’. The First Eurasian Symposium on the Problems of Strength of Materials and Machines for Cold Climate Regions was held in Yakutsk on July 16-20, 2002, and gathered more than 370 participants from many Russian scientific institutes and from abroad. The Chairman of the Organizing Committee was Academician of the Russian Academy of Sciences, Doctor of Technical Sciences V.P. Larionov, director of the Institute of Physical-Technical Problems of the North and Chair of the Yakut Scientific Center. This success gave reason to make EURASTRENCOLD Symposium regular. The informational support of the ESIS was provided from 2019 when the First International Conference on Integrity and Lifetime in Extreme Environment (ILEE-2019) held in Yakutsk. The historical aspects and future of research activity in the Republic of Sakha (Yakutia) and Far East, and international scientific collaboration in Europe and Asia has been discussed in the paper.
Abstract Nowadays, the close interaction between the Russian academic science and industry come t... more Abstract Nowadays, the close interaction between the Russian academic science and industry come true by means of The Digital Economics of Russian Federation State Program. It has pass ahead partially of the Industry 4.0 and 5.0 European programs in case of realization of the analysis of development and control methods of the knowledge-intensive complex engineering systems (CES) that are competitive in the world market of high technologies, products, goods and services for the Arctic and the Subarctic. It has been shown how by the using chaos theory and Bayesian principles on the base of multilevel simulation it could be formulated a general scientific and methodological approach to the problem of identifying, analyzing and choosing alternatives for fundamental research area in order to ensure the disruptive development of manufacturing technologies of the CES production for the long term. The methodology for criterion formation of preference, ranking and multi-criteria selection of the most priority alternatives of the fundamental research for Digital Economics, Industry and Society concepts for the Arctic and the Subarctic has been considered.
International Journal of Engineering Technologies and Management Research, 2020
During welding, the heat produced during the process can affect the microhardness and the microst... more During welding, the heat produced during the process can affect the microhardness and the microstructure of the material. The change in the microstructure and the microhardness can be discovered by carrying out a microhardness test on the welded sample and compare changes in the three different zones i.e the base, the weld and the Heat affected zone or by carrying out a micro structural examination on the welded sample and see the grain dispersion in relation to their sizes. In this work, weld quality of manual arc welded samples of low-carbon steel St3spdestined for bridge construction to be used in Cameroon has been investigated. After a chemical analysis of the material, a micro hardness test and a micro structural examination was also done. Results show that a composition of pearlite and ferrite was seen with the print of the id enter of the micro hardness test. The formation of pearlite and ferrite in base metalis composed of 20/80 respectively. For weld zone and HAZ it changes...
The Integrity means not only the structural strength and performance of technical systems. The In... more The Integrity means not only the structural strength and performance of technical systems. The Integrity here is consolidating of the engineers and scientist in many research areas. The extreme environment has a significant influence on infrastructures and living beings during the development and service life in or close to the Arctic regions. Russia has a large boundary to Arctic and has a huge territory classified as a frigid zone. So the extreme environment contains conditions that are hard to survive even for steel structures due to extreme temperature, corrosion, inappropriate service and repair. Many problem should by discussed therefor including the structural integrity as the strength and mechanical properties and behavior of steel, polymer and composite structures, the phase transition processes, inhomogeneity of materials and thermal physics. The transport problem is a very important in Extreme environment, also the energy supply and mining technology. So it is an exigency to discussing and conferencing for the integrity and lifetime in extreme conditions.
The weld joints are characterized by microstructure inhomogeneity and defects due to non-uniform ... more The weld joints are characterized by microstructure inhomogeneity and defects due to non-uniform heating and cooling particularly at service while operating in extremely cold environment. Vickers micro hardness measurement was done on hard probes of welded samples of low-alloyed 14H2GMR and low-carbon St3sp steel. Experimental study was carried out to see the thermal cycling influence on the heat-affected zone properties. It was discovered that, welding at-40°C does not lead to a significant increase of steel micro hardness as compare to welding at +20°C despite the large difference in cooling rates. It was also discovered that, the crack grows mainly along the grain boundaries of martensite and bainite (as over chilled austenite), but in some cases passes through the grain body and cuts across it at 14H2GMR for pipe steel. For structural St2sp steel the inter granular cracks are revealed both in weld metal and in the heat affected zone nevertheless of milder test conditions against hard technological probes.
Abstract Some aspects of damage accumulation modeling and brittle fracture processes mechanisms u... more Abstract Some aspects of damage accumulation modeling and brittle fracture processes mechanisms under the combined effect of mechanical loading and hydrogen has been discussed in the article. New mechanism of brittle fracture for metallic materials based on dislocation and phonon structure fingerprints and lattice hydrogen content under the static and dynamic loading at low temperature condition has been proposed. The mechanism based on theoretical research and experimental and numerical studies. The experiments include the energy spectrum of internal friction determination and impact toughness testing for low-temperature brittle-ductile transition revealing. The numerical study based on damage accumulation modeling under the influence of up-hill diffusion in the elastic-plastic problem of solid state by finite element method. A new simple activation model of low temperature and hydrogen influence on damage accumulation process has been proposed. The model shows the rate of damage strong dependence of stress level and hydrogen content, and test temperature. The combination of low temperature and high hydrogen content is most dangerous, so the weld structures in extreme environment such as the Arctic and Subarctic regions have a high risk of breakage. So it is possible to estimate the energy and phonon spectrum of crystal lattice, and predict the properties of microcrystalline and nanostructured materials with the high cold-short threshold on the base of such the approach. There are the recommendations propose to improve the cold resistance of steels and alloys by controlling the characteristics of the dislocation structure of new materials with polycrystalline and ultrafine-grained structure.
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