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Novel Methodologies for Preventing Crack Propagation in Steel Gas Pipelines Considering the Temperature Effect

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Structural Durability & Health Monitoring 2025年第1期19卷 1-23页

作者： Nurlan Zhangabay Ulzhan Ibraimova Marco Bonopera Ulanbator Suleimenov Konstantin Avramov Maryna Chernobryvko Aigerim Yessengali Department of Architecture and Urban Planning Mukhtar Auezov South Kazakhstan UniversityShymkent160012Kazakhstan Department of Industrial Civil and Road Construction Mukhtar Auezov South Kazakhstan UniversityShymkent160012Kazakhstan Mechanics Sound&Vibration LaboratoryDepartment of Civil EngineeringCollege of EngineeringNational Taiwan UniversityTaipei10617Taiwan Department of Reability&Dynamic Strength A.Pidhornyi Institute of Mechanical Engineering Problems of National Academy of Sciences of UkraineKharkiv61046Ukraine

Using the software ANSYS-19.2/Explicit Dynamics,this study performedﬁnite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crack,strengthened by steel wire *** effects of the thread tensile force of the steel winding in the form of single rings at the crack edges and the wires with different winding diameters and pitches were also *** results showed that the strengthening was preferably executed at a minimum value of the thread tensile force,which was 6.4%more effective than that at its maximum *** analysis of the inﬂuence of the winding dia-meters showed that the equivalent stresses increased by 32%from the beginning of the crack growth until the wire *** increment in winding diameter decelerated the disclosure of the edge crack and reduced its length by 8.2%.The analysis of the inﬂuence of the winding pitch showed that decreasing the distance between the winding turns also led to a 33.6%reduction in the length of the straight crack and a 7.9%reduction in the maximum stres-ses on the strengthened pipeline *** analysis of the temperature effect on the pipeline material,within a range from-40℃ to+50℃,resulted in a crack length change of up to 5.8%.As the temperature dropped,the crack length *** such a temperature range,the maximum stresses were observed along the cen-tral area of the crack,which were equal to 413 MPa at+50℃ and 440 MPa at-40℃.The results also showed that the presence of the steel winding in the pipeline signiﬁcantly reduced the length of crack propagation up to 8.4 times,depending on the temperature effect and design parameters of *** work integrated the existing methods for crack localization along steel gas pipelines.

关键词： Crack propagation ﬁnite-element internal pressure prestressing steel gas pipeline temperature effect

Effect of Nb-V microalloying on the hot deformation behavior of medium Mn steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 360-368页

作者： Yumeng Wang Qinyi Guo Bin Hu Haiwen Luo School of metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The influence of Nb-V microalloying on the hot deformation behavior and microstructures of medium Mn steel(MMS)was investigated by uniaxial hot compression *** establishing the constitutive equations for simulating the measured flow curves,we successfully constructed deformation activation energy(Q)maps and processing maps for identifying the region of flow *** concluded the following consequences of Nb-V alloying for MMS.(i)The critical strain increases and the increment diminishes with the increasing deformation temperature,suggesting that NbC precipitates more efficiently retard dynamic recrystallization(DRX)in MMS compared with solute Nb.(ii)The deformation activation energy of MMS is significantly increased and even higher than that of some reported high Mn steels,suggesting that its ability to retard DRX is greater than that of the high Mn content.(iii)The hot workability of MMS is improved by narrowing the hot processing window for the unstable flow stress,in which fine recrystallized and coarse unrecrystallized grains are present.

关键词： medium manganese steel niobium-vanadium microalloying flow behavior dynamic recrystallization hot workability

Simultaneously Enhancing Strength, Ductility and Corrosion Resistance of a Martensitic Stainless Steel via Substituting Carbon by Nitrogen

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Acta Metallurgica Sinica(English Letters) 2023年第5期36卷 705-716页

作者： Fuyang Li Jialong Tian Huabing Li L.M.Deineko Zhouhua Jiang School of Metallurgy Northeastern UniversityShenyang110819China national metallurgical academy of ukraine 4Haharina Ave.Dnipro49600Ukraine

Two martensitic stainless steels of 2Cr12Ni6 type hardened and tempered at 773 K have been studied:the first with 0.2%carbon content and the second with partial replacement of carbon by nitrogen(C0.1N0.1)in the first *** is found that the partial substitution of carbon with nitrogen contributed to an increase in ductility and strength of the steel,presumably due to the formation of more dispersive ***,the addition of nitrogen suppressed the precipitation of carbonitrides,so that the solid solution strengthening effect of C0.1N0.1 did not decrease significantly after tempering *** addition,the partial replacement of carbon by nitrogen contributed to improved ability against pitting corrosion(PC)in chloride-containing medium(3.5%NaCl at 303 K).The higher resistance to PC of tempered nitrogen-containing steel is apparently due to the lower content of massive carbonitrides,especially the reduced aggregation at grain *** leads to a lower acidity and aggressiveness of the test solution near the sample surface due to the accumulation of NH4^(+) ammonium ions in *** a result of nitrogen addition,exception for Cr_(23)C_(6) and VC,Cr_(2)N and(Cr,V)N type precipitates have also been found in C0.1N0.1 steel and this is consistent with the thermodynamic calculation *** conclusion,substituting carbon by nitrogen in traditional martensitic stainless steel could realize the simultaneous improvement of multiple properties of martensitic stainless *** result provides a promising composition optimization route to develop novel martensitic stainless steels.

关键词： Martensitic stainless steel Strength and ductility Pitting Carbonitrides

Overview of in-situ oxygen production technologies for lunar resources

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 233-255页

作者： Youpeng Xu Sheng Pang Liangwei Cong Guoyu Qian Dong Wang Laishi Li Yusheng Wu Zhi Wang College of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China CAS Key Laboratory of Green Process and Engineering National Engineering Research Center for Green Recycling of Strategic Metal ResourcesInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Innovation academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

The rich resources and unique environment of the Moon make it an ideal location for human expansion and the utilization of extraterrestrial ***,crucial for supporting human life on the Moon,can be extracted from lunar regolith,which is highly rich in oxygen and contains polymetallic *** oxygen and metal extraction can be achieved using existing metallurgical ***,the ample reserves of water ice on the Moon offer another means for oxygen *** paper offers a detailed overview of the leading technologies for achieving oxygen production on the Moon,drawing from an analysis of lunar resources and environmental *** delves into the principles,processes,advantages,and drawbacks of water-ice electrolysis,two-step oxygen production from lunar regolith,and one-step oxygen production from lunar *** two-step methods involve hydrogen reduction,carbothermal reduction,and hydrometallurgy,while the one-step methods encompass fluorination/chlorination,high-temperature decomposition,molten salt electrolysis,and molten regolith electrolysis(MOE).Following a thorough comparison of raw materials,equipment,technology,and economic viability,MOE is identified as the most promising approach for future in-situ oxygen production on the *** the corrosion characteristics of molten lunar regolith at high temperatures,along with the Moon's low-gravity environment,the development of inexpensive and stable inert anodes and electrolysis devices that can easily collect oxygen is critical for promoting MOE technology on the *** review significantly contributes to our understanding of in-situ oxygen production technologies on the Moon and supports upcoming lunar exploration initiatives.

关键词： lunar resources in-situ oxygen production space metallurgy molten lunar regolith electrolysis

Phenomena at three-phase electroslag remelting

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China Foundry 2021年第6期18卷 557-564页

作者： Zhong-li Liu Lev Medovar Ganna Stovpchenko Volodymyr Petrenko Artem Sybir Yev.Volchenkov Yantai University Yantai 264005ShandongChina E.O.Paton Electric Welding Institute Kyiv 03180Ukraine national metallurgical academy of ukraine Dnipro 49600Ukraine

The electroslag remelting(ESR)process is widely used to produce high-quality ingots and billets for high-alloyed steels and *** the single-phase and three-phase alternating current diagram with bifilar and monofilar connection are in use for heavy ingot *** numerical simulation of the three-phase bifilar circuit for the 120 t three-phase bifilar six-electrode ESR furnace at different variants of electric connection was presented and *** the bifilar diagram of power supply,the geometrical location of electrodes in a mould holds critical importance for performances:the close location of bifilar pair electrodes provides the highest heat productivity,but the equidistant location of electrodes gives a much more uniform heat *** monofilar mulit-electrode diagram of three-phase connection without phase shift shows the most uniform distribution of potential and heat generation as well as a favorable magnetic field that makes this kind the most promising for providing a high quality of heavy ingots.

关键词： electroslag remelting three-phase circuit bifilar monofilar simulation heavy ingot

Pore structure and mechanical properties of directionally solidi ed porous aluminum alloys

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China Foundry 2014年第1期11卷 1-7页

作者： Komissarchuk Olga Xu Zhengbin Hao Hai Zhang Xinglu Vladimir Karpov School of Materials Science and Engineering Dalian University of Technology Department of Materials Science and Metal Processing National Metallurgical Academy of Ukraine

Porous aluminum alloys produced by the metal-gas eutectic method or GASAR process need to be performed under a certain pressure of hydrogen, and to carry over melt to a tailor-made apparatus that ensures directional solidif ication. Hydrogen is driven out of the melt, and then the quasi-cylindrical pores normal to the solidif ication front are usually formed. In the research, the effects of processing parameters(saturation pressure, solidif ication pressure, temperature, and holding time) on the pore structure and porosity of porous aluminum alloys were analyzed. The mechanical properties of Al-Mg alloys were studied by the compressive tests, and the advantages of the porous structure were indicated. By using the GASAR method, pure aluminum, Al-3wt.%Mg, Al-6wt.%Mg and Al-35wt.%Mg alloys with oriented pores have been successfully produced under processing conditions of varying gas pressure, and the relationship between the f inal pore structure and the solidif ication pressure, as well as the inf luences of Mg quantity on the pore size, porosity and mechanical properties of AlMg alloy were investigated. The results show that a higher pressure of solidif ication tends to yield smaller pores in aluminum and its alloys. In the case of Al-Mg alloys, it was proved that with the increasing of Mg amount, the mechanical properties of the alloys sharply deteriorate. However, since Al-3%Mg and Al-6wt.%Mg alloys are ductile metals, their porous samples have greater compressive strength than that of the dense samples due to the existence of pores. It gives the opportunity to use them in industry at the same conditions as dense alloys with savings in weight and material consumption.

关键词： porous aluminum alloys GASAR solidification pressure pore structure directional solidification

3d-visualization of magnesium strengthening mechanisms for a description of experimentally obtained data of alloying effect in Mg-Ga system

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Journal of Magnesium and Alloys 2020年第2期8卷 546-551页

作者： J.A.Khokhlova M.A.Khokhlov Paton Electric Welding Institute of national academy of Sciences of ukraine KyivUkraine

Based on laws of theory of materials strengthening were discribed the experimentally obtained alloying effect in Mg-Ga system and shown using program for 3d atomic *** known from our experiments a homogeneous"wavy"microstructure of the diffusion zone forms as result of mass-transfer of molten gallium into the volume of magnesium *** chemical composition shows Mg 65%*** Ga 35%*** X-ray spectra diffraction data-Mg5Ga2 intermetallic phase *** intermetallic diffusion zone provides the significant strengthening effect of microstructure which was determined experimentally by the indentation *** 3-d visualization shows the reaction and changing of an original crystal structure of magnesium atomic lattice upon diffusion doping with foreign atoms of gallium and then is shown the coalescence of Mg5Ga2 intermetallic crystal with crystals surfaces of ***,investigated Mg-alloy strengthening at alloying with Ga explained by two main *** first is the formation of intermetallic phases with the ordering and consolidation of the crystal structure of the matrix by the ligature atoms,which is the key factor of the strengthening mechanism fixed ***,when hexagonal and orthorhombic atomic structures growth according to their spatial type,a significant disorientation of structural fragments occurs,an increase in the density of the amorphous transition layer,a twinning of the structure in the interphase boundaries,which leads to the formation of intrinsic mutual deformation and a high level of internal stresses.

关键词： Magnesium Gallium Alloying Strengthening Atom 3d

Triggering of Major Brain Disorders by Protons and ATP:The Role of ASICs and P2X Receptors

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Neuroscience Bulletin 2023年第5期39卷 845-862页

作者： Andri Cherninskyi Maksim Storozhuk Oleksandr Maximyuk Vyacheslav Kulyk Oleg Krishtal Bogomoletz Institute of Physiology of national academy of Sciences of ukraine Kyiv 01024Ukraine

Adenosine triphosphate(ATP)is well-known as a universal source of energy in living *** known is that this molecule has a variety of important signaling func-tions:it activates a variety of specific metabotropic(P2Y)and ionotropic(P2X)receptors in neuronal and non-neu-ronal cell ***,a wide variety of signaling func-tions well fits the ubiquitous presence of ATP in the *** more ubiquitous are *** from the unspe-cific interaction of protons with any protein,many physi-ological processes are affected by protons acting on specific ionotropic receptors--acid-sensing ion channels(ASICs).Both protons(acidification)and ATP are locally elevated in various pathological *** these fundamentally important molecules as agonists,ASICs and P2X receptors signal a variety of major brain *** we briefly outline the physiological roles of ASICs and P2X receptors,focusing on the brain pathologies involving these receptors.

关键词： ASICs P2X receptors Stroke Chronic pain Epilepsy Neurodegenerative Psychiatric diseases

Structure and Properties of Nanostructured Vacuum-Deposited Foils of Invar Fe–(35–38 wt%)Ni Alloys

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Journal of Materials Science & Technology 2015年第11期31卷 1079-1086页

作者： V.M.Nadutov A.I.Ustinov S.A.Demchenkov Ye.O.Svystunov V.S.Skorodzievski G.V.Kurdyumov Institute for Metal Physics of national academy of Sciences of ukraine E.O.Paton Electric Welding Institute of national academy of Sciences of ukraine

The process of electron beam vacuum deposition of the Fe-（35-38 wt%）Ni alloys at substrate temperatures Ts from 300 to700 ℃ were used to produce vacuum-deposited foils with the FCC structure, differing by the size of characteristic microstructural elements （grains and subgrains）. It was shown that refinement of foil microstructural elements to nanoscale is accompanied by their microhardness increase up to 4-5 GPa. The change of the thermal expansion coefficient （TEC） of the nanostructured （NS） foil of the Fe-35.1Ni alloy within the temperature range from -50 to 150 ℃ has some deviation from that observed for cast Invar alloy of the same composition. It has been found that the main factors affecting the peculiarities of thermal expansion of the NS foil can be related to the presence of small fraction of BCC- phase in them, high level of crystalline lattice microstrains and inhomogeneous magnetic order in FCC- phase. It was shown that as a result of additional thermal treatment of NS foils their invar properties become similar to that observed for cast Invar alloy but mechanical properties remain on the same level.

关键词： Fe-Ni alloys Electron beam physical vapor deposition (EBPVD) Nanostructured materials Hardness Thermal expansion Mossbauer spectroscopy