Physical Mesomechanics最新文献

{"title":"Evolution of the Structure and Properties of Cu-56Au (at %) Alloy during L10-Type Atomic Ordering","authors":"O. S. Novikova,&nbsp;E. G. Volkova,&nbsp;P. O. Podgorbunskaya,&nbsp;D. A. Zgibnev,&nbsp;A. A. Gavrilova,&nbsp;N. A. Kruglikov,&nbsp;A. Yu. Volkov","doi":"10.1134/S102995992460109X","DOIUrl":"10.1134/S102995992460109X","url":null,"abstract":"<p>The ordered gold-copper alloy Cu–56 at % Au is widely used in instrument engineering as conductors of weak electrical signals in control devices. However, microstructural evolution and changes in the physicomechanical properties of the alloy during the disorder → order phase transformation (A1 → L1₀) are still poorly understood. In the present paper, we study the evolution of the microstructure and properties of the quenched Cu–56 at % Au alloy during the disorder → order phase transformation. The annealing time at 250°C ranged from 10 min to 4 months. Microstructural studies were performed using transmission electron microscopy, the ratio of volume fractions of the ordered and disordered phases was determined using X-ray diffraction analysis and resistometric measurement, and material properties were measured in mechanical tensile and microhardness tests. The fraction of the ordered phase, strength properties, and specific electrical resistivity were plotted as a function of the annealing time. It is found that the maximum strength properties correspond to the two-phase state (A1 + L1₀) of the alloy with an approximately equal phase ratio. It is shown that, with an increase in the fraction of the ordered phase, the tensile strain hardening coefficient almost doubles.</p>","PeriodicalId":726,"journal":{"name":"Physical Mesomechanics","volume":"28 1","pages":"123 - 133"},"PeriodicalIF":1.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143396735","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 Structural Evolution and Load Level on the Properties of Creep and Recovery Curves Generated by a Nonlinear Model for Thixotropic Viscoelastoplastic Media","authors":"A. V. Khokhlov,&nbsp;V. V. Gulin","doi":"10.1134/S1029959923600891","DOIUrl":"10.1134/S1029959923600891","url":null,"abstract":"<p>This paper continues the systematic analytical study of the properties of the previously constructed nonlinear shear deformation model of thixotropic viscoelastoplastic media, which takes into account the mutual influence of deformation and structural evolution. The ability of the model to describe the behavior of liquid and solid media (solidifying/solidified) is analyzed. The focus is on the response properties of the model to step loading, in particular, creep and recovery curves and curves of incremental cyclic loading. The aim is to find out what typical effects of viscoelastoplastic media the model can describe and what unusual effects/properties are generated by changes in the structuredness compared to typical creep and recovery curves of structurally stable materials. A system of two nonlinear differential equations is obtained to describe the response of the system to a given loading (not deformation) program, such as creep under constant load and arbitrary piecewise constant stress. A general solution to the Cauchy problem for this system is constructed in an explicit form for six arbitrary material parameters and an increasing material function governing the model, i.e. expressions are derived as quadratures for the shear strain and structuredness as functions of time, which depend on the initial conditions and all parameters of the model and loading program. An analytical study is performed for the basic properties of the family of creep and recovery curves and the structural evolution in these processes, their dependence on the time (monotonicity and convexity intervals, extrema, asymptotes, etc.), on the material parameters and function of the model, on the stress level and initial structuredness of the material, and on the initial stage of loading to a given stress before creep. It is proven that creep curves always increase with time, do not have inflection points, and have oblique asymptotes (although their initial arcs can differ considerably from straight lines). The structuredness at constant stress (at each incremental loading step, in particular, at zero stress) is always monotonic unlike other loading modes, but can decrease or increase depending on the relationship between the stress level and the initial structuredness at each incremental loading step. The model is shown to describe unusual effects observed in tests on some materials, e.g. the difference in the absolute values of strain jumps during loading and complete unloading and the opposite sign of residual strain with respect to the stress and strain signs at the creep stage. Several applicability indicators of the model are found, which can be conveniently verified using experimental data. Responses of the model to cyclic loading/unloading (creep/recovery), induced oscillations of the structuredness, and their effect on the rate of plastic strain accumulation are studied.</p>","PeriodicalId":726,"journal":{"name":"Physical Mesomechanics","volume":"28 1","pages":"66 - 90"},"PeriodicalIF":1.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143396738","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":"Autowave Physics of Inhomogeneous Plastic Flow","authors":"L. B. Zuev,&nbsp;Yu. A. Khon","doi":"10.1134/S1029959924601325","DOIUrl":"10.1134/S1029959924601325","url":null,"abstract":"<p>The paper presents the history of the autowave model for localized plastic flow developed at the ISPMS SB RAS and describes the fundamentals of the autowave approach to the problem of inhomogeneous plastic flow based on the idea of plastic flow localization. Attention is drawn to the historical aspect of the development of new ideas about the phenomenon of plasticity. The main relations of the autowave plasticity model (conformity principle, elastoplastic and mass invariants of plastic strain) are given, and its technical applications are considered. The two-component model is used to develop the theory of inhomogeneous plastic flow, taking into account the correlated (collective) properties of ensembles of deformation carriers. It is shown that solutions of the obtained equations describe patterns observed at all stages of strain hardening.</p>","PeriodicalId":726,"journal":{"name":"Physical Mesomechanics","volume":"28 1","pages":"1 - 26"},"PeriodicalIF":1.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143396734","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":"Modeling the Response of Additively Manufactured Heterogeneous Metal-Ceramic Specimens to Dynamic Impact","authors":"A. E. Buzyurkin,&nbsp;A. E. Kraus,&nbsp;E. I. Kraus,&nbsp;V. M. Fomin,&nbsp;I. I. Shabalin","doi":"10.1134/S1029959924601118","DOIUrl":"10.1134/S1029959924601118","url":null,"abstract":"<p>The paper reports on experiments and numerical simulation of high-speed impact loading of additively manufactured heterogeneous specimens. It is shown that the proposed model of direct numerical simulation of a heterogeneous material based on random distribution of given materials over difference cells accurately reproduces the processes of deformation, fracture, and cratering under impact loading. A series of calculations are made to determine the ballistic efficiency of additively manufactured heterogeneous metal-ceramic specimens using the DoP (depth-of-penetration) method. A procedure is proposed for estimating the efficiency of heterogeneous metal-ceramic specimens, revealing local maxima in it.</p>","PeriodicalId":726,"journal":{"name":"Physical Mesomechanics","volume":"28 1","pages":"27 - 42"},"PeriodicalIF":1.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143396733","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":"Oxygen and Nitrogen Diffusion in Titanium Nitride","authors":"A. V. Bakulin,&nbsp;L. S. Chumakova,&nbsp;S. E. Kulkova","doi":"10.1134/S1029959924600836","DOIUrl":"10.1134/S1029959924600836","url":null,"abstract":"<p>Diffusion of oxygen and nitrogen in titanium nitride was studied using the projector augmented wave method in combination with transition state theory. Atomic migration energies were calculated for two diffusion mechanisms (interstitial and vacancy ones). It was found that the oxygen migration energy by the interstitial mechanism is ~0.3 eV lower than that by the nitrogen vacancy mechanism. However, the indirect mechanism of diffusion through the body-centered position of the cubic lattice formed of titanium and nitrogen atoms is more preferable. The estimation of the temperature-dependent coefficient of oxygen and nitrogen diffusion in titanium nitride by the two mechanisms showed their strong dependence on the concentration of thermal vacancies. It was shown that the interstitial diffusion of nitrogen occurs at temperatures below 1500°C, and the vacancy diffusion mechanism prevails at high temperatures. The calculated activation energies and diffusion coefficients showed good agreement with the experimental values. At high concentrations of constitutional vacancies, the coefficients of oxygen diffusion by both mechanisms are comparable with the experimental values for TiO₂, and the values obtained at low concentrations remain several orders of magnitude higher than those for Al₂O₃.</p>","PeriodicalId":726,"journal":{"name":"Physical Mesomechanics","volume":"28 1","pages":"55 - 65"},"PeriodicalIF":1.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143396467","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":"On the Propagation of Bulk Waves in Functionally Graded Beams with Consideration for Imperfection","authors":"T. Tang,&nbsp;J. Gao,&nbsp;C. Jin,&nbsp;X. Huang","doi":"10.1134/S1029959924601581","DOIUrl":"10.1134/S1029959924601581","url":null,"abstract":"<p>Wave propagation analysis can be employed in various fields, such as nondestructive testing and structural health monitoring, which makes it so interesting and attractive. In the present investigation, an analytical method based on an exponential function was used to solve the wave propagation problem in functionally graded (FG) beams with consideration for imperfection via refined higher-order shear deformation theory. The recently developed porosity-dependent homogenization model was used to analyze the influence of imperfection on the wave dispersion behavior of porous beams. Material properties of FG beams were assumed to change across the thickness. The conventional porosity model illustrates a linear relationship between the porosity coefficient and material properties. However, the influence of porosity is actually characterized by a nonlinear relationship. This statement rose from some experimental investigations. To examine the interchange between the porous beam and foundation, Winkler–Pasternak two-parameter models were used as the elastic foundation. Uniform temperature change is taken into account to study the thermal environment effect. The principle of Hamilton is implemented to derive equations of motion for imperfect FG beams. The obtained governing equations were analytically solved. The influence of the wave number, porosity coefficient, temperature change, gradient index, length-to-thickness ratio, Winkler and Pasternak coefficients on the wave propagation in porous FG beams was studied.</p>","PeriodicalId":726,"journal":{"name":"Physical Mesomechanics","volume":"28 1","pages":"134 - 144"},"PeriodicalIF":1.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143396569","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":"Structure and Properties of the Ribbon Produced from Fe-Co-Ni-Si-B Soft Magnetic Alloy by Spinning","authors":"A. P. Semin,&nbsp;V. E. Gromov,&nbsp;Yu. F. Ivanov,&nbsp;S. V. Panin,&nbsp;E. A. Kolubaev,&nbsp;I. Yu. Litovchenko,&nbsp;S. V. Borovskii","doi":"10.1134/S1029959924601179","DOIUrl":"10.1134/S1029959924601179","url":null,"abstract":"<p>A ribbon of soft-magnetic high-entropy alloy Fe-Co-Ni-Si-B with the nonequiatomic composition and the thickness of ~70 μm was produced by spinning. Its structure, mechanical, tribological and magnetic properties were analyzed by experimental methods of the modern materials science. It was found that the studied material is in an amorphous (X-ray amorphous) state. The microhardness of the ribbon was HV = 8 GPa. Transmission electron microscopy on electrolytically polished foils showed that the size of structural elements of the ribbon did not exceed 10 nm. Ion etching led to partial crystallization of the foil and growth of nanocrystallites to several tens of nanometers. The tensile strength of the ribbon was more than 590 MPa at a low elongation to failure (1%). The distribution patterns of the longitudinal and transverse strain components were constructed, according to which no strain macrolocalization occurred up to fracture. The wear rate in the longitudinal direction of the ribbon was more than 4 times higher than that in the transverse direction. The magnetic properties were characterized by a hysteresis loop, with the maximum value of the specific magnetic moment being ~120 emu/g.</p>","PeriodicalId":726,"journal":{"name":"Physical Mesomechanics","volume":"28 1","pages":"43 - 54"},"PeriodicalIF":1.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143396466","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":"Lüders and Portevin–Le Chatelier Bands at the Stage of Elastoplastic Transition: Nucleation and Propagation","authors":"Yu. A. Khon","doi":"10.1134/S1029959923600854","DOIUrl":"10.1134/S1029959923600854","url":null,"abstract":"<p>The work is devoted to the theoretical study of the nucleation and propagation of Lüders bands on the yield plateau and of moving Portevin–Le Chatelier bands of type A (solitary waves of plastic flow) at the stage of parabolic hardening during strain aging. The proposed model considers collective deformation modes on the spatiotemporal meso- and macroscales. Strain aging changes the state of a deformable medium on the mesoscale. Deformation of a medium under constant-rate uniaxial tension is described by a system of two coupled nonlinear parabolic equations for dynamic order parameters. The coefficients of these equations depend on the impurity concentration. On the yield plateau, solutions of the equations in the form of a switching wave describe the nucleation (at the yield drop stage) and propagation of Lüders bands. Depending on the temperature and rate of deformation during strain aging, a yield drop may be repeated on the yield plateau. Its formation changes the mode of Lüders band propagation from constant-velocity continuous to discrete one. At the strain hardening stage, the nucleation and propagation of the Portevin–Le Chatelier band are described by solutions in the form of a traveling autosoliton (a solitary wave of plastic flow).</p>","PeriodicalId":726,"journal":{"name":"Physical Mesomechanics","volume":"28 1","pages":"91 - 100"},"PeriodicalIF":1.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143396571","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":"Electrical Disintegration of Reinforced Concrete: Experiment and Simulation","authors":"R. A. Bakeev,&nbsp;A. S. Yudin,&nbsp;N. S. Kuznetsova,&nbsp;D. V. Zhgun,&nbsp;Yu. P. Stefanov","doi":"10.1134/S1029959924601106","DOIUrl":"10.1134/S1029959924601106","url":null,"abstract":"<p>The paper reports on physical experiments on disintegration of reinforced concrete by the electric pulse method based on the Vorobiev effect. Concrete is fractured under the action of a compression wave propagating from the discharge channel between the electrode on the concrete surface and the reinforcement. Disintegration experiments are conducted on pebble concrete. It is shown that a single pulse results in separate cracks in the material on retention of its integrity. Disintegration of concrete and cavitation at the point of application of the electrode begin after the second or third pulse. Computer simulation is made for the action of an expanding discharge channel on reinforced concrete. A structural model of reinforced concrete is plotted, explicitly taking into account its main constituents, namely, cement, stone inclusions, and reinforcement. The inelastic behavior of cement is described within the modified Drucker–Prager–Nikolaevsky model with the nonassociated flow rule for quasi-brittle media. Cracking is simulated using the fracture criterion based on tensile stresses. The performed numerical simulation confirms the conclusions of the physical experiment: a single pulse causes the formation of separate cracks parallel to the free surface, and the network of horizontal, vertical and inclined cracks appears in the cement after 2–3 pulses, resulting in a cavity at the point of application of the electrode. Cavitation in reinforced concrete is governed by the presence of stone inclusions, whose boundaries serve as sites of redistribution of maximum tensile stresses and formation of vertical and inclined cracks, as well as of accumulation of irreversible strains and stresses retained in the cement after the first pulse.</p>","PeriodicalId":726,"journal":{"name":"Physical Mesomechanics","volume":"28 1","pages":"101 - 110"},"PeriodicalIF":1.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143396736","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 the Structure, Phase Transformations, and Shape Memory Effect in Amorphous-Crystalline TiNiCu Alloy","authors":"A. V. Shelyakov,&nbsp;N. N. Sitnikov,&nbsp;D. A. Khachatrian,&nbsp;I. A. Zaletova","doi":"10.1134/S1029959924601155","DOIUrl":"10.1134/S1029959924601155","url":null,"abstract":"<p>Layered amorphous-crystalline TiNiCu alloy ribbons produced by ultrarapid quenching from the liquid state (melt spinning technique) show the two-way shape memory effect without additional processing, which makes them applicable to various micromechanical devices (microtweezers) for gripping and manipulating microobjects. The present work is devoted to the study of the influence of the rejuvenation process (cryogenic thermal cycling) and the thickness of the crystalline layer on the structure and functional properties of quasi-binary TiNi-TiCu alloy with the copper content 25 at %. It is shown that thickening of the crystalline layer significantly increases not only the enthalpy of martensitic transformation but also its critical temperatures and affects the alloy crystallization pattern and temperatures. Rejuvenation treatment transforms the interface between the amorphous and crystalline layers and changes the ratio between the B19 martensitic phase and the residual B2 austenitic phase in the martensitic state, which affects the martensitic transformation parameters. In addition, cryothermal treatment causes a noticeable increase in reversible strain (magnitude of the two-way shape memory effect) and significantly narrows the temperature hysteresis of shape changing, which can improve the functional properties of microdevices based on rapidly quenched amorphous-crystalline ribbons.</p>","PeriodicalId":726,"journal":{"name":"Physical Mesomechanics","volume":"28 1","pages":"111 - 122"},"PeriodicalIF":1.8,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143396737","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}