Inorganic Materials最新文献

{"title":"Using Parameters of the Dynamic Impact Bending Curve to Assess the Nature of Fracture in Pipe Steels Within the Ductile–Brittle Transition Range","authors":"M. A. Valov,&nbsp;A. V. Molyarov,&nbsp;A. M. Arsenkin","doi":"10.1134/S0020168526701037","DOIUrl":"10.1134/S0020168526701037","url":null,"abstract":"<p>The use of modern pendulum impact testers capable of recording the specimen’s deformation diagram during loading has made it possible to consider the impact bending test not only as a standard acceptance test for verifying that the metal meets normative requirements. Recording the deformation diagram in force–displacement coordinates makes it possible to obtain a more objective assessment of the metal’s resistance to fracture and, more generally, to broaden understanding of the fracture mechanism, especially in the range of transition temperatures. For this reason, analysis of dynamic impact bending curves for information on the nature of fracture is of interest: in particular, for determining the quantitative ratio of ductile and brittle components in the fracture. In the present work, using steels of grades 06GFBA, 26KhMFA and 35KhGMA used for the manufacture of oil‑and‑gas line pipe, it is experimentally shown that the force values at characteristic points of a pre‑smoothed dynamic impact bending curve allow a reasonably accurate determination of the fraction of the ductile component (FDC) by a calculated method, without visual analysis of the fracture surfaces of broken specimens. The investigations showed that the brittle component in the fracture is formed at the moment a sharp jump appears on the diagram, while the specimen deflection characterizes its resistance to the initiation and growth of a brittle crack during fracture. A pronounced dependence of the impact bending curve parameters on test temperature can serve as a qualitative indicator for identifying incorrectly determined values at the characteristic points. By calculating the FDC, a cold brittleness curve was obtained and the ductile–brittle transition temperature was determined. Comparison of the cold brittleness curves constructed from the calculated and experimental (measured visually from fracture surfaces) FDC data showed close values of the critical brittleness temperature. This confirms the possibility of using the calculation method for a rapid and effective assessment of that temperature with satisfactory accuracy, especially when a large number of specimens are involved. It can also be applied as an additional control method during acceptance testing.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"62 3","pages":"420 - 430"},"PeriodicalIF":0.5,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148394836","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":"The Efficiency Illustration of Biomimetic Fastening of Composite Parts","authors":"A. N. Polilov,&nbsp;D. D. Vlasov,&nbsp;O. Yu. Volkova","doi":"10.1134/S0020168526701025","DOIUrl":"10.1134/S0020168526701025","url":null,"abstract":"<p>One of the main challenges in designing composite structures is developing reliable fastening methods, since traditional drilled holes sever load-bearing fibers, causing significant stress concentration and reduced strength. The aim of this work was to develop and illustrate a bio-inspired fastening method for composite parts by creating a curvilinear reinforcement structure that imitates the knot zone in wood. It is shown that an iterative computer algorithm for modelling fiber trajectories that “flow around” the hole makes it possible to build a reinforcement structure in which the fiber-overloading coefficient is only 1.3, instead of the stress concentration factor of about five in a plate of unidirectional carbon composite with a circular hole. Experiments on wooden specimens with removed knots and drilled holes, as well as on composite specimens with curvilinear reinforcement manufactured by 3D printing, confirmed the efficiency of the proposed approach. Preserving the reinforcement structure in the knot zone means that the hole left by the removed knot does not affect strength, and failure occurs away from the hole. The results obtained confirm the promising potential of using biomimetic joint designs to substantially increase the load-bearing capacity and durability of composite fastener joints, which is especially important for large-scale aerospace structures.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"62 3","pages":"417 - 419"},"PeriodicalIF":0.5,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148394960","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":"Tests of Prototypes of Transport Packaging Kits for Spent Nuclear Fuel Under External Impact Loadings","authors":"A. G. Kazantsev,&nbsp;V. V. Abramov,&nbsp;O. M. Petrov,&nbsp;M. V. Radchenko","doi":"10.1134/S0020168526700950","DOIUrl":"10.1134/S0020168526700950","url":null,"abstract":"<p>A methodology is described for testing prototypes of transport packaging kits (TPK) for spent nuclear fuel under external impact loadings (drop onto a rigid pin, drop onto dampers, impact of a crashing aircraft), taking into account scale effects and the presence of manufacturing defects in the TPK body. The main idea of the method is that artificial crack-like defects are introduced into the prototype body in the zone of maximum tensile stresses. Their sizes are determined by the allowable manufacturing defectiveness of the body material (for forgings, castings, welds), the prototype scale, and the scatter of the fracture toughness characteristics of the body material. The conservatism of the simulation tests is ensured by designing the prototype with artificial defects so that its probability of failure exceeds that of the full-scale TPK. Results are presented of calculations of the stress–strain state and strength of transport packaging kit prototypes for the BREST-OD-300 reactor unit under drop tests and aircraft-impact tests. Using the master-curve concept, probabilities of failure were estimated for the full-scale TPK and for reduced-scale prototypes as a function of test temperature. It is shown that the steel grade 09N2MFB A-A used to manufacture the TPK bodies for the BREST-OD-300 reactor unit has high dynamic fracture toughness, ensuring the integrity of the TPK at lowered temperatures down to –60°C.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"62 3","pages":"357 - 366"},"PeriodicalIF":0.5,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148394749","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":"Comprehensive Experimental Analysis of Deformation and Cracking Processes in a Reinforced Concrete Element","authors":"D. Yu. Sarkisov,&nbsp;A. M. Ustinov,&nbsp;A. S. Plyaskin,&nbsp;E. S. Useinov","doi":"10.1134/S0020168526700962","DOIUrl":"10.1134/S0020168526700962","url":null,"abstract":"<p>Due to the increasing complexity of building structures and the increasing level and variability of their loading, the task of determining precise deformation values within them is a pressing issue. In structural materials, deformations are inextricably linked to stresses, the level of which determines the strength and safety of buildings and structures. The processes of deformation development are quite complex and depend on many factors. However, to record them during testing of building structures, one of several well-known methods is most often used, each with its own advantages and disadvantages. To obtain a more complete picture of deformation and crack development in reinforced concrete elements, the combined use of these methods appears promising. The objective of this study is to improve the strength and reliability of reinforced concrete elements through a comprehensive analysis of deformation and cracking processes using electrical strain gauges, digital image correlation, and heat emission recording. A comprehensive experimental analysis methodology was developed and trial tensile tests were conducted on a reinforced concrete specimen, collecting strain data using three methods: a thermal imager, a Vic-3D system, and strain gauges. Experimental data obtained are presented and a comprehensive comparative analysis is conducted. Advantages and disadvantages of the proposed approach are highlighted. Further developments of the proposed methodology are outlined.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"62 3","pages":"367 - 378"},"PeriodicalIF":0.5,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148394897","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":"Instrumental Indentation as a Tool of Express Control of Mechanical Properties in Aluminum Alloys","authors":"V. M. Matyunin,&nbsp;A. Yu. Marchenkov,&nbsp;R. Yu. Agafonov,&nbsp;N. O. Tsvetkova,&nbsp;M. P. Petrova,&nbsp;G. B. Sviridov","doi":"10.1134/S0020168526701013","DOIUrl":"10.1134/S0020168526701013","url":null,"abstract":"<p>A technique to determine the mechanical properties of aluminum alloys is developed based on instrumental indentation using a ball indenter. The method is based on the correlation between the maximum even strain under sample tension and the strain hardening parameter in the indentation plastic region. The procedures allow deriving a formula to express the yield strength to the ultimate strength ratio through the strain hardening parameter. The values of the loading degree required to achieve the maximum unrecovered Brinell hardness are established. For the tested aluminum alloys the values are proportional to the ultimate tensile strength with a constant conversion factor. The ultimate tensile strength and the ratio of yield strength to ultimate tensile strength allow calculating the yield strength of the alloy. Usually this parameter is quite difficult to estimate using conventional indentation techniques. Given the unambiguous correlation between the ratio of yield strength to ultimate tensile strength and the strain hardening parameter, we suggest applying it as a diagnostic parameter to estimate the degree of fragility of structural materials. The higher this parameter, the more prone the material is to develop the brittle fracture. The proposed method to determine mechanical properties using instrumental indentation is sufficiently simple to automate resulting in increasing the rate of monitoring the mechanical properties in aluminum alloys.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"62 3","pages":"410 - 416"},"PeriodicalIF":0.5,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148394913","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":"Study of Viscoelastic Properties of Frost-Resistant Rubbers","authors":"K. S. Kravchuk,&nbsp;G. Kh. Sultanova","doi":"10.1134/S0020168526700937","DOIUrl":"10.1134/S0020168526700937","url":null,"abstract":"<p>The standard method of dynamic mechanical analysis for determining the viscoelastic properties of highly elastic materials involves testing bulk specimens of a specific shape and size. This paper presents the results of a study of the viscoelastic properties of nitrile butadiene rubber-based rubbers using dynamic mechanical analysis (nanoDMA). A new experimental setup for nanodynamic testing of frost-resistant rubbers was used in the temperature range from –60 to +60°C. Methodology applied involved studying the specimens in a localized near-surface region. For nanoDMA testing, the required parameters were set in the indenter module software: load, frequency and amplitude of indenter oscillations, and test duration. Indenters of various geometries and materials were allowed. It was found that at low temperatures close to the glass transition temperature, the rubber properties change dramatically. Temperature dependences of elastic modulus at frequencies of 0.1, 0.2, 0.5, 1, 6, and 30 Hz revealed significant changes in sample properties at temperatures around –40°C. Experimental setup and methodology proposed can be used for quality control of products, such as rings intended for tribological testing.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"62 3","pages":"343 - 347"},"PeriodicalIF":0.5,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148394818","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":"Investigation of the State of Surface Layer of Oil and Gas Pipelines","authors":"A. E. Zorin,&nbsp;A. S. Romantsov","doi":"10.1134/S0020168526700846","DOIUrl":"10.1134/S0020168526700846","url":null,"abstract":"<p>Existing main pipeline systems consist of pipes produced using various technologies. The rolled metal of the pipes is subjected to thermomechanical treatment, which results in its strong plastic deformation without subsequent phase transformations and recrystallization. In addition to the positive effect of such processing, a negative effect of preserving undesirable technological heredity may also arise, especially in the near-surface layers of contact deformation. It is also known that due to the operational peculiarities of pipelines, the outer surface of pipes is an area of increased stress concentration and initiation of destruction. In this regard, a study of the surface layer of new and used oil and gas pipeline pipes and pipeline fittings manufactured using the most common rolling technologies is carried out. The index of brittleness of the pipe metal at various depths is determined, which is calculated using a specially developed technique based on the processing of microhardness values and the study of the morphology of localized shifts near the print during micro-indentation. It is established that metal embrittlement can occur at all stages of the life cycle of a constructure. In this case, the modes of controlled rolling of the sheet have a decisive influence on the formation of the initial embrittlement of the pipe metal. This begins to appear during the production of steels of K60 strength class and increases in steels of K65 strength class. In this case, significant heterogeneity of metal embrittlement by depth is also noted: in the surface layers (with a depth of 0.5–1.0 mm), it is significantly higher than in the center of the volume. This peculiarity can contribute to the initiation and development of stress-corrosion cracks that correlates with the statistics of detection of these defects. The possibility of assessing the degree of metal embrittlement during pipeline operation using specialized equipment is demonstrated.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"62 3","pages":"273 - 282"},"PeriodicalIF":0.5,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148394869","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":"Dependence of Kinetics of the Material Cyclic Hardening Indicator on Profile of High-Temperature Low Cycle Loading","authors":"M. M. Gadenin","doi":"10.1134/S0020168526701001","DOIUrl":"10.1134/S0020168526701001","url":null,"abstract":"<p>The results obtained in experimental and computational studies of kinetics of stresses and strains and material properties provide the basis for developing and applying criteria of cyclic fracturing, as well as for carrying out refined computations of structural parts exposed to low cycle loading. Various operational regimes, including the shapes of load cycles that affect the hardening or softening characteristics of the material, are taken into account by establishing patterns in changing the basic parameters of the equations of state that describe the kinetics of local cyclic elastoplastic deformations as functions of the load cycle parameters. In this case, the relationship between stresses and strains under cyclic loading beyond the elastic limit is characterized by diagrams of cyclic elastoplastic deformation plotted against the number of loading half‑cycles (or cycles). To describe the cyclic deformation diagrams beyond the elastic limit, the most widely used approach involves the power‑law approximation. The key parameter of this approximation deals with the cyclic hardening exponent—the exponent in the power‑law relationship between the relative values of cyclic stresses and strains in a cycle. For selecting the basic parameters of the equations of state. The basic parameters of the equations of state can be rectified if in addition to the characteristics of stress‑strain states the mechanical properties of materials are obtained from short‑term and long‑term static and cyclic tests. The established patterns of varying cyclic hardening exponent allow associating this exponent with the shape of load cycles, as well as with hardening and softening effects of the material caused by high‑frequency deformation under a dual‑frequency loading regime.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"62 3","pages":"400 - 409"},"PeriodicalIF":0.5,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148394815","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":"Anisotropic Mechanical Properties of 316L Stainless Steel Billets Produced by Direct Laser Deposition","authors":"S. P. Samoilov,&nbsp;A. O. Chernyavsky,&nbsp;S. Yu. Ivanov","doi":"10.1134/S0020168526700925","DOIUrl":"10.1134/S0020168526700925","url":null,"abstract":"<p>The purpose of this work is to assess anisotropy in the mechanical properties of parts produced by additive manufacturing from high-temperature steels when billet dimensions are such that specimens cannot be cut in three mutually perpendicular directions. We studied cylindrical specimens prepared from 316L steel plates produced by direct laser deposition at process parameters that made it possible to reproduce mechanical properties of large parts. Quasi-static isothermal tensile tests to failure at room and elevated temperatures on specimens cut in two possible directions (in the build and printing directions) showed that their stress–strain curves in these directions differed little, suggesting that the mechanical properties of the billet were only slightly anisotropic. At the same time, the cross section of an originally circular specimen was elliptical after tensile testing, in both the necking region and the uniform deformation region, pointing to anisotropy of the billet. Therefore, the billet and the specimens cut in the two directions in question differed in mechanical properties. Numerical simulation of specimen deformation by the finite element method with the ANSYS software suite has demonstrated the feasibility of finding a description of the material such that the behavior of a model specimen will be identical to that obtained experimentally, concerning both the load–elongation curve and cross section ellipticity. To assess the effect of the anisotropy of the material on the strength of structural components, we simulated a heat-stressed model structure typical of additive manufacturing. The results demonstrate that taking into account the anisotropy reduces the calculated cyclic durability by about a factor of 2. This work provides impetus for a more detailed study of anisotropy despite a number of methodological difficulties, such as additive manufacturing of billets suitable for cutting specimens in three mutually perpendicular directions and the ability to increase the amount of testing.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"62 3","pages":"337 - 342"},"PeriodicalIF":0.5,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148394895","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":"Assessment of the Structural and Mechanical Heterogeneity of the Material of Hydroturbine Runners Based on Hardness Measurements","authors":"E. V. Aniskovich,&nbsp;V. V. Moskvichev","doi":"10.1134/S0020168526700883","DOIUrl":"10.1134/S0020168526700883","url":null,"abstract":"<p>The structural heterogeneity and mechanical property characteristics of the material of turbine runners of hydroelectric generating units exhibiting service‑related defects were investigated. Design features of the turbine runners are noted and the metal microstructure is presented. The chemical composition of the steel was determined by laser‑spark emission spectrometry using a portable laser styloscope. Mechanical properties were obtained from static tensile tests on a tensile testing machine. Impact energy and impact toughness were determined from tests of specimens with a U‑shaped notch in impact bending on a pendulum impact tester over the temperature range from +20 to –30°C. Fracture toughness tests were also performed on a testing machine. Specimens for all tests were cut from a fragment of a runner blade. Hardness values were obtained using a portable dynamic hardness tester by the Brinell method on four blades from the suction (non‑pressure) side in zones of cavitation damage. The main operational problems of hydroturbines associated with cavitation damage to the metal are described. The runner blades were provisionally divided into zones according to the degree of cavitation damage. Based on Brinell hardness measurements, mechanical property characteristics, yield strength and ultimate tensile strength, were estimated. Statistical processing of the obtained values was carried out; distribution histograms were constructed and the characteristic probability distribution law determined; coefficients of heterogeneity were calculated and graphs of the statistical distributions of the mechanical property values were plotted.</p>","PeriodicalId":585,"journal":{"name":"Inorganic Materials","volume":"62 3","pages":"308 - 316"},"PeriodicalIF":0.5,"publicationDate":"2026-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148394910","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}