Journal of Metastable and Nanocrystalline Materials最新文献_第6页

The Investigation of Nanowires Properties in the Process of Deformation 纳米线在变形过程中的性能研究

Journal of Metastable and Nanocrystalline Materials Pub Date : 2018-01-12 DOI: 10.4028/www.scientific.net/JMNM.30.34

M. Starostenkov, O. V. Yashin, A. Yashin

引用次数: 0

Weakly Stable Structural-Phase States of a Submicrocrystalline Alloy Grade 2 in the Weld Zone Obtained Using Electron-Beam Welding 电子束焊接获得的2级亚微晶合金焊接区弱稳定组织相态

Journal of Metastable and Nanocrystalline Materials Pub Date : 2018-01-12 DOI: 10.4028/www.scientific.net/JMNM.30.60

K. Kurgan, V. Klimenov, A. Klopotov, Yurii A. Abzaev, A. Potekaev, D. Lychagin, M. Marzol

{"title":"Weakly Stable Structural-Phase States of a Submicrocrystalline Alloy Grade 2 in the Weld Zone Obtained Using Electron-Beam Welding","authors":"K. Kurgan, V. Klimenov, A. Klopotov, Yurii A. Abzaev, A. Potekaev, D. Lychagin, M. Marzol","doi":"10.4028/www.scientific.net/JMNM.30.60","DOIUrl":"https://doi.org/10.4028/www.scientific.net/JMNM.30.60","url":null,"abstract":"The structural-phase state of weld joints of the samples of Grade 2 alloys with micro- and submicrocrystalline structure is studied using methods of X-ray diffraction analysis. The weld joint was obtained by joining plates with a thickness of 2 mm using the electron-beam welding method. It is established that the transfer of the titanium alloy Grade 2 from the microcrystalline state into the submicrocrystalline state during the process of gradual grinding of grains in the samples by the abc-pressing method at a parallel stepwise decrease of the temperature in the range of 750-500 °C leads to an intensive introduction of oxygen atoms into the crystalline lattice of the solid solution a-Ti. The presence of an increased content of oxygen atoms in the crystalline lattice of the solid solution a-Ti in the submicrocrystalline state in the Grade 2 alloy in the weld zone and in the heat-affected zone promotes the formation of metastable phases w-Ti and α''-Ti. The obtained results made it possible to assume that in the process of electron-beam welding in the Grade 2 alloy in the submicrocrystalline state, an increased concentration of interstitial oxygen atoms in the crystalline lattice of the solid solution based on a–Ti plays a significant role in the formation of a wide range of structural-phase states in the weld zone and in the heat-affected zone.","PeriodicalId":177608,"journal":{"name":"Journal of Metastable and Nanocrystalline Materials","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122252446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Phase Composition and Defect Substructure of Strengthening Layer Surfaced on Low Alloyed Steel 低合金钢表面强化层的相组成及缺陷子结构

Journal of Metastable and Nanocrystalline Materials Pub Date : 2018-01-12 DOI: 10.4028/www.scientific.net/JMNM.30.28

Y. Ivanov, V. Gromov, S. Konovalov, V. Kormyshev, R. Qin, O. Semina

引用次数: 0

The Formation and Migration Energy of Bivacancy in fcc Metals fcc金属中双空位的形成和迁移能

Journal of Metastable and Nanocrystalline Materials Pub Date : 2018-01-12 DOI: 10.4028/www.scientific.net/JMNM.30.11

G. Poletaev, I. Zorya, M. Starostenkov

引用次数: 0

Interaction of Hydrogen Atom with Edge Dislocation in Pd and Ni Pd和Ni中氢原子与边位错的相互作用

Journal of Metastable and Nanocrystalline Materials Pub Date : 2018-01-12 DOI: 10.4028/www.scientific.net/JMNM.30.46

I. Zorya, G. Poletaev, M. Starostenkov

引用次数: 0

Biphase Model of Plastic Deformation in Electric Fields 电场中塑性变形的双相模型

Journal of Metastable and Nanocrystalline Materials Pub Date : 2018-01-12 DOI: 10.4028/www.scientific.net/JMNM.30.17

V. Sarychev, S. Nevskii, A. Semin, V. Gromov

{"title":"Biphase Model of Plastic Deformation in Electric Fields","authors":"V. Sarychev, S. Nevskii, A. Semin, V. Gromov","doi":"10.4028/www.scientific.net/JMNM.30.17","DOIUrl":"https://doi.org/10.4028/www.scientific.net/JMNM.30.17","url":null,"abstract":"The object of the research is creep deformation proceeding in the conditions of electrostatic field effect. The purpose of the research is to develop the mathematical model of creep under the electrostatic field effect from the positions of representations about the wave nature of plastic deformation process. The theoretical studies of electrostatic field effect being characterized by small (up to ± 1V) potentials on the basis of mass, momentum and energy conservation in two-dimensional formulation were carried out in the process of research. The material being deformed was represented as two phase heterogeneous medium. The first component is excited and being responsible for structure transformation, the second one is unexcited and disconnected with them. For each of the components the laws of mass and momentum conservation were written. For electric fields the Maxwell equations were written. For the first time the two phase filtration model of creep was developed as a result of the research. The model takes into account the inhomogeneity of plastic deformation under electrostatic field effect. The dispersion relation for the waves of plasticity is obtained.","PeriodicalId":177608,"journal":{"name":"Journal of Metastable and Nanocrystalline Materials","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134152336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Analysis of the Structure and Thermal Stability of Cu@Si Nanoparticles Cu@Si纳米颗粒的结构和热稳定性分析

Journal of Metastable and Nanocrystalline Materials Pub Date : 2018-01-12 DOI: 10.4028/www.scientific.net/JMNM.30.52

Y. Gafner, S. Gafner, A. Nomoev, S. Bardakhanov

引用次数: 1

The Necessary Duration of a Molecular Dynamics Experiment for the Diffusion Coefficient Calculation 计算扩散系数所需的分子动力学实验时间

Journal of Metastable and Nanocrystalline Materials Pub Date : 2018-01-12 DOI: 10.4028/www.scientific.net/JMNM.30.22

G. Poletaev, E. S. Medvedeva, Darya V. Novoselova, I. Zorya, M. Starostenkov

引用次数: 2

Physical Nature of Structure and Properties Degradation of Rail Surface after Long Term Operation 长期运行后钢轨表面结构和性能退化的物理性质

Journal of Metastable and Nanocrystalline Materials Pub Date : 2018-01-12 DOI: 10.4028/www.scientific.net/JMNM.30.39

V. Gromov, A. Yuriev, O. Peregudov, S. Konovalov, Y. Ivanov, A. Glezer, A. Semin

{"title":"Physical Nature of Structure and Properties Degradation of Rail Surface after Long Term Operation","authors":"V. Gromov, A. Yuriev, O. Peregudov, S. Konovalov, Y. Ivanov, A. Glezer, A. Semin","doi":"10.4028/www.scientific.net/JMNM.30.39","DOIUrl":"https://doi.org/10.4028/www.scientific.net/JMNM.30.39","url":null,"abstract":"By methods of optical, scanning and transmission electron diffraction microscopy and microhardness and tribology parameters measurement the changes regularities of structure-phase states, defect substructure of rails surface after the long term operation (passed tonnage of gross weight 500 and 1000 mln. tons) were established. It is shown that the wear rate increases in 3 and 3.4 times after passed tonnage of gross weight 500 and 1000 mln. tons, accordingly, and the friction coefficient decreases in 1.4 and 1.1 times. The cementite plates are destroying absolutely and cementite particles of around form with the sizes 10-50 nm are forming after passed tonnage 500 mln tons. The appearance of dynamical recrystallization initial stages is marked after the passed tonnage 1000 mln tons. It is shown that the operation of steel rails is accompanied by full fractures in surface layers with lamellar pearlite grains and the formation of ferrite–carbide mixtures with nanosized particles. The deformation of steel increases the densities of scalar and excess dislocations, the curvature–torsion values of the crystal lattice, and the amplitudes of internal stress fields. The possible mechanisms of established regularities are discussed. It is noted that two competitive processes can take place during rails long term operation: 1. Process of cutting of cementite particles followed by their carrying out into the volume of ferrite grains or plates (in the structure of pearlite). 2. Process of cutting, the subsequent dissolution of cementite particles, transition of carbon atoms to dislocations (into Cottrell atmospheres), transition of carbon atoms by dislocations into volume of ferrite grains or plates followed by repeat formation of nanosize cementite particles.","PeriodicalId":177608,"journal":{"name":"Journal of Metastable and Nanocrystalline Materials","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126386490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Molecular Dynamics Study of Nonequilibrium [112] Tilt Grain Boundaries in Ni and their Relaxation under Cyclic Deformation Ni非平衡态[112]倾斜晶界及其在循环变形下弛豫的分子动力学研究

Journal of Metastable and Nanocrystalline Materials Pub Date : 2018-01-12 DOI: 10.4028/www.scientific.net/JMNM.30.1

A. Nazarov, R. Murzaev

{"title":"Molecular Dynamics Study of Nonequilibrium [112] Tilt Grain Boundaries in Ni and their Relaxation under Cyclic Deformation","authors":"A. Nazarov, R. Murzaev","doi":"10.4028/www.scientific.net/JMNM.30.1","DOIUrl":"https://doi.org/10.4028/www.scientific.net/JMNM.30.1","url":null,"abstract":"Atomic structure of nonequilibrium [112] tilt grain boundaries in nickel containing disclination dipoles is studied by means of molecular dynamics simulations. Initial systems for simulations are constructed by joining together pieces of two bicrystals one of which contains a symmetric tilt GB S=11 / 62.96° and the other a GB S=105 / 57.12°, or S=125 / 55.39°, or S=31 / 52.20°, so disclination dipoles with strengths w = 5.84°, 7.58° and 10.76° are created. Stress maps plotted after relaxation at zero temperature indicate the presence of high long-range stresses induced by disclination dipoles. Excess energy of GBs due to the nonequilibrium structure is calculated. Effect of oscillating tension-compression stresses on the nonequilibrium GB structure is studied at temperature T = 300 K. The simulations show that the oscillating stress results in a generation of partial lattice dislocations by the GB, their glide across grains and sink at appropriate surfaces that results in a compensation of the disclination stress fields and recovery of an equilibrium GB structure and energy.","PeriodicalId":177608,"journal":{"name":"Journal of Metastable and Nanocrystalline Materials","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125025224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3