Metallurgist最新文献

{"title":"Modeling of the thermal state of an ingot in the crystallizer of a slab CCM with straight and beveled corners","authors":"Igor M. Yachikov,&nbsp;T. I. Shafikov,&nbsp;G. A. Podosyan,&nbsp;M. N. Samodurova","doi":"10.1007/s11015-025-01899-3","DOIUrl":"10.1007/s11015-025-01899-3","url":null,"abstract":"<div><p>The procedure of cooling ingots in continuous-casting machines affects both the reliability and productivity of the equipment and the quality of ingots obtained as a result. Insufficient heat exchange between the liquid metal and the wall of the mold leads to a decrease in the thickness of the solid shell of the ingot promoting the formation of surface defects and, in the process of pulling of the ingot out of the mold, leads to the appearance of emergency ruptures. At the same time, excessive heat transfer leads to an increase in the thickness of the solid shell, which results in the redundant shrinkage of the ingot surface accompanied by the formation of a gap between the solid shell of the ingot and the walls of the mold. The appearance of a gap filled with air leads to a sharp decrease in the intensity of heat transfer and accelerates the process wear of the copper walls of the mold. There exists a design of the copper walls with end bevels (protrusions, shoulders, and “whiskers”), which makes it possible to decrease the normal component of forces formed in the process of wear, lower the temperature gradient and the level of stress concentration in the corners of the ingot by increasing the angle from 90 to 135°, and also make the thickness of the “stocking” of solid crust in the corner of the mold closer to the perimeter of the crystallizer. However, the thermal state of the formed ingot for the indicated design of the crystallizer remains poorly studied. We develop a mathematical model and an algorithm for the evaluation of the thermal state of an ingot (with rectangular cross section and angles beveled at 45°) placed in the mold. This enables us to analyze the process of solidification of the ingot in a slab continuous-casting machine. Based on the created mathematical model and the proposed algorithm for solving the boundary-value problem, we created a computer program “Simulation of slab hardening.” By using the results of computer simulations, we obtained the diagrams of temperature distributions in the cross section of the ingot at the exit of the mold of the continuous-casting machine with straight or beveled corners. We also present the dependences of variations of the thickness of solid crust along the height of the crystallizer. The results obtained in the present work can be used to choose the rational shape and the rate of taper of the mold walls in a slab continuous casting machine guaranteeing the decrease in the size of the gap between the solid crust of the ingot and the working surface of the mold.</p></div>","PeriodicalId":702,"journal":{"name":"Metallurgist","volume":"68 12","pages":"1858 - 1869"},"PeriodicalIF":0.8,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145163347","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}

{"title":"Methodological assessment of human factor impact on the reliability of production system","authors":"A. L. Sotnikov,&nbsp;N. A. Denisova,&nbsp;O. V. Knyazkov,&nbsp;B. F. Belelyubskii,&nbsp;E. E. Balakhnina","doi":"10.1007/s11015-025-01908-5","DOIUrl":"10.1007/s11015-025-01908-5","url":null,"abstract":"<div><p>In this work, the influence of the performance of the welder on the quality of the stringer bead layer of a control welded joint with real-time registration of process parameters is studied. The analysis, identification and description of the problem areas in the welder’s performance that led to the unsatisfactory quality of the stringer bead layer were evaluated. The causes of the errors of the welder related to factors such as: lack of time, physical overload, level of training, psychological state, and sensory deprivation come to the foreground. Real-time monitoring of welding process parameters with the help of modern software and hardware systems allowed to compare statistical data corresponding to defect-free weld sections with similar data of weld sections with defects. The data obtained revealed the causes of defect formation related to violations of welding techniques. At the same time, the welding parameters corresponded to the established values. A methodological approach to determining the influence of the human factor on the reliability of the production system, in particular on reliability indicators such as the probability of failure-free operation of the system and its duration, was proposed. With this approach it is possible to develop specific recommendations for the organization of welding production in order to reduce the influence of the human factor on the quality of welds. These are organizational measures that involve the division of the welder’s work functions according to the type of work between the welder and support personnel (weld inspectors, grinders, and fitters, etc.).</p></div>","PeriodicalId":702,"journal":{"name":"Metallurgist","volume":"68 12","pages":"1949 - 1958"},"PeriodicalIF":0.8,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145163345","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}

{"title":"Experimental study of electric drives used in rolling mills during asymmetric rolling of sheets and stripes","authors":"G. P. Kornilov,&nbsp;A. M. Pesin,&nbsp;A. A. Bochkarev,&nbsp;L. V. Nosov,&nbsp;I. A. Pesin","doi":"10.1007/s11015-025-01897-5","DOIUrl":"10.1007/s11015-025-01897-5","url":null,"abstract":"<div><p>The authors review the basic principles of organizing the process of asymmetric rolling (AR) and the results of its application on single- and five-stand mills. The main positive qualities of the process, such as improved physical and mechanical properties, and enhanced strip microstructure, are shown. The limitations of the maximum values of the asymmetry factor are justified: for multi-stand mills with an individual drive, this parameter depends on the degree of impact of the local control systems (e.g., thickness, tension, load division), and typically does not exceed 1.15. At the same time, attention should be paid to the possibility of switching the driven roll drive to the generator mode, and the ensuing consequences. For the laboratory and industrial mill 400, the maximum value of high-speed asymmetry is determined by the power of the driving roll motor and the power circuit type of the driven roll converter in the generator mode. Oscillograms of the driving roll motor currents are provided, confirming an uneven nature of deformation along the length of the strip in case of significant asymmetry.</p></div>","PeriodicalId":702,"journal":{"name":"Metallurgist","volume":"68 12","pages":"1839 - 1848"},"PeriodicalIF":0.8,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145163346","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}

{"title":"Practical aspects of industrial use of high-strength iron aluminide intermetallic compounds and promising directions for their production","authors":"S. G. Zhilin,&nbsp;V. V. Predein,&nbsp;V. A. Khudyakova,&nbsp;N. A. Bogdanova","doi":"10.1007/s11015-025-01905-8","DOIUrl":"10.1007/s11015-025-01905-8","url":null,"abstract":"<div><p>The global trend of metal consumption growth and the expansion of the range of metal-intensive production determines the increase in demand for alloys characterized by improved physical, mechanical, and operational properties. Among the materials with unique properties are intermetallic iron-aluminum alloys, whose products can be used as coatings for structural elements subjected to increased mechanical stress at high temperatures or in chemically aggressive environments. The attractiveness of iron-aluminum intermetallics is attributable to several factors, including the relatively low cost of the primary components, and their potential application as ligatures. The limited plasticity of these materials results in low demand for products that are subjected to alternating or shock loads under typical operating conditions. In addition, the complexity of their manufacturing processes further limits their application. This necessitates the development of technologies aimed at addressing these significant limitations. This paper presents a review of modern methods of obtaining intermetallic iron-aluminum alloys and adjusting their characteristics, which determines the prospects for expanding their application.</p></div>","PeriodicalId":702,"journal":{"name":"Metallurgist","volume":"68 12","pages":"1923 - 1933"},"PeriodicalIF":0.8,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145163338","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}

{"title":"Production of strontium hexaferrite permanent magnets by the CIM technology","authors":"B. D. Chernyshev,&nbsp;I. V. Schetinin","doi":"10.1007/s11015-025-01904-9","DOIUrl":"10.1007/s11015-025-01904-9","url":null,"abstract":"<div><p>The possibility of producing permanent magnets based on strontium hexaferrite using Ceramic Injection Molding (CIM) technology was investigated. A ceramic process was used to produce powders suitable for use in CIM technology. Based on the obtained strontium hexaferrite powder, a granulate was prepared for the production of green parts. The obtained parts were subjected to the process of removing the binder—debinding, which resulted in the production of brown parts, which contain a smaller amount of binder and have an open-pore structure. Permanent magnets with dimensions 10×10×5 mm were obtained by sintering of the brown parts in an oxidizing atmosphere. The level of magnetic parameters of strontium hexaferrite samples exceeded 70% of the values typical for industrial isotropic barium hexaferrite magnets according to GOST 24063-80. This is attributed to the presence of pores in the sintered products.</p></div>","PeriodicalId":702,"journal":{"name":"Metallurgist","volume":"68 12","pages":"1914 - 1922"},"PeriodicalIF":0.8,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145163341","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}

{"title":"Effect of yttrium and erbium on the microstructure and superplasticity of Ti–4Al–3Mo–1V alloy","authors":"Alena Yu. Trishina,&nbsp;Anton D. Kotov,&nbsp;Maria N. Postnikova,&nbsp;Anastasia V. Mikhaylovskaya","doi":"10.1007/s11015-025-01890-y","DOIUrl":"10.1007/s11015-025-01890-y","url":null,"abstract":"<div><p>The influence of small Y and Er additions (0.2 wt.%) on the supraplastic behavior and microstructural evolution of Ti–Al–Mo–V alloys during thermomechanical processing and superplastic deformation was investigated. Alloying with 0.2% Y can effectively modify the cast structure, decreasing the mean grain size from 670 to 225 μm, while addition of 0.2% Er exhibited no modifying effect. Thermomechanical processing promoted the refinement of oxide particles, resulting in compact particles measuring ≈0.2 μm for the Er-bearing alloy and ≈0.1 μm for the Y‑bearing alloy. The alloys with Y and Er additions and the base alloy without additives exhibited close superplastic characteristics at temperatures of 775 and 875 °C, strain-rate sensitivity coefficient <i>m</i> = 0.45–0.55, and elongation ≈400–800% at strain rates of 1·10⁻³ and 2·10⁻⁴ s⁻¹. Alloying with Y and Er reduced the flow stress during superplastic deformation, which is attributed to the acceleration of recrystallization and globularization of the microstructure due to oxide particles. Also, the inhibiting effect of Y oxide particles on grain size during annealing in the single-phase <i>β</i>-region and during superplastic deformation at low strain rates was revealed, while no effect was observed in the alloy with Er.</p></div>","PeriodicalId":702,"journal":{"name":"Metallurgist","volume":"68 11","pages":"1764 - 1775"},"PeriodicalIF":0.8,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145168486","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}

{"title":"Embrittlement factors during the fracture of ERW welded joints of low-carbon low-alloy steel pipes according to the results of Charpy impact tests","authors":"P. P. Stepanov,&nbsp;K. G. Vorkachev,&nbsp;A. E. Sorokin,&nbsp;O. A. Bagmet,&nbsp;L. I. Efron,&nbsp;M. M. Kantor,&nbsp;V. A. Bozhenov","doi":"10.1007/s11015-025-01878-8","DOIUrl":"10.1007/s11015-025-01878-8","url":null,"abstract":"<div><p>In order to determine the influence of various embrittlement factors on the fracture of welded joints of a pipe made of low-carbon low-alloy steel obtained by electric resistance welding (ERW), we performed multiple Charpy impact tests. The fracture surfaces were analyzed by using macro- and microfractographic techniques. The microstructure was characterized by means of optical microscopy, scanning electron microscopy (SEM) and electron backscattered diffraction in SEM. It was discovered that the formation of large bainitic grains in the ferrite-bainite microstructure formed in the core of the ERW pipe wall, as well as the presence of globular 2–7 μm oxysulfide nonmetallic inclusions, exert a significant embrittlement effect on the base metal of the ERW pipe joints. The formation of a predominantly ferritic coarse-grained microstructure with a 1.4-fold increase in grain size and a 2-fold increase in the content of {001} crystallographic clusters parallel to the fracture surface, as well as the formation of elongated deformed oxysulfide inclusions inherited from the base metal in the zone of the fusion line of the ERW pipe joint are responsible for the decrease in the level of toughness and the appearance of brittle fractures with low values of Charpy impact toughness in the fusion line zone.</p></div>","PeriodicalId":702,"journal":{"name":"Metallurgist","volume":"68 11","pages":"1636 - 1649"},"PeriodicalIF":0.8,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145168487","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}

{"title":"Technological features of the production of steel strips of various ranges in casting and rolling complexes","authors":"A. V. Muntin","doi":"10.1007/s11015-025-01879-7","DOIUrl":"10.1007/s11015-025-01879-7","url":null,"abstract":"<div><p>Casting and rolling complexes (CRC) used for the production of steel strips are, in fact, contemporary and in-demand metallurgical units. In the global steel production of about 1800 mln. tons per year, the production capacity of all CRC used for strip production throughout the world (more than 70 complexes) constitutes about 120–140 mln. tons (i.e., about 7–8% of the total amount) and continues to increase with startups of new projects. The only CRC intended for the production of steel strips in Russia was put into operation at the OMK Vyksa Plant in 2008. By using their own system for the development of new technologies and products, experts of the Engineering and Technological Center of the UMC managed not only to master the production of numerous unique products but also to develop their own recommendations concerning the selection of equipment required for the CRC depending on the assortment of produced products. We perform the analysis of the technological modes of production and the CRC equipment used throughout the world. We determine the specific features of the influence of the applied equipment and the parameters of the process of production of hot-rolled strips of eight main groups of products on their qualitative characteristics. A scientifically justified procedure is proposed for the choice of the rational composition of equipment for the CRC rolling mills. The results of commercial testing and introduction of the products at the OMK Vyksa Plant are presented.</p></div>","PeriodicalId":702,"journal":{"name":"Metallurgist","volume":"68 11","pages":"1650 - 1666"},"PeriodicalIF":0.8,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145167320","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}

{"title":"Integrated solutions for improving the performance characteristics of solid-rolled railway wheels","authors":"A. V. Muntin,&nbsp;D. E. Kerentsev,&nbsp;I. S. Krasov,&nbsp;D. A. Pyshkin","doi":"10.1007/s11015-025-01877-9","DOIUrl":"10.1007/s11015-025-01877-9","url":null,"abstract":"<div><p>The fatigue limit of wheel steels of grades 2, T, and L (GOST 10791) was determined in order to improve the performance characteristics of solid rolled railway wheels. The test methodology is based on the requirements of GOST 25.502. According to the test results, the relationship between the strength and the fatigue limit of the investigated wheel steels is determined. The results are proposed to facilitate the optimization of the wheel thickness depending on the material strength. In order to improve the characteristics of wheel life, resistance to wear, and chip formation, the methodology of designing wheels with rolling surface profiles K‑70 and K‑65 based on the software package Universal Mechanism is presented, as well as the efficiency indicators of their implementation on the wheels of freight and passenger cars. In order to predict the total service life of the wheels, the calculation and experimental methodology developed by the St. Petersburg State University of Railway Transport of Emperor Alexander I, was tested in the conditions of the scientific and experimental base of JSC OMK (United Metallurgical Company, Moscow, Russia) to estimate the service life of wheels of grades 2, T and L for various purposes. Mechanical properties of promising steel grade B with bainite structure are presented. It is shown that they significantly exceed the quality indicators of standard wheel steels.</p></div>","PeriodicalId":702,"journal":{"name":"Metallurgist","volume":"68 11","pages":"1625 - 1635"},"PeriodicalIF":0.8,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145167881","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}

{"title":"Influence of local combined thermal effect on the intensity of residual stresses in a plate made of Hadfield steel (110G13L)","authors":"Evgeniy E. Abashkin,&nbsp;Anastasia V. Tkacheva","doi":"10.1007/s11015-025-01863-1","DOIUrl":"10.1007/s11015-025-01863-1","url":null,"abstract":"<div><p>The restoration of worn-out parts by electric-arc surface welding using a flux-cored wire with an aluminothermic filler is investigated. The study focuses on a plate made of Hadfield steel (110G13L), a material known for its challenging weldability. The welding process involves depositing three layers onto a preconditioned surface. The surface welding process is mathematically described based on the Prandtl–Reuss model incorporating the Duhamel–Neumann law in place of Hooke’s law and a modified von Mises yield criterion to account for the viscous properties of materials during irreversible deformation. The elastic moduli and yield stress are assumed temperature-dependent. Laboratory studies were conducted to determine the combined thermal effect on the welding process. It is concluded that applying the combined thermal effect during surfacing with flux-cored wire with aluminothermic filler reduces the intensity of residual stresses, thereby enhancing the performance and durability of the welded part.</p></div>","PeriodicalId":702,"journal":{"name":"Metallurgist","volume":"68 10","pages":"1477 - 1487"},"PeriodicalIF":0.8,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143667893","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}