Journal articles: 'Macroscopic deformation'

1

Luo, J. J., and I. M. Daniel. "Deformation of Inhomogeneous Elastic Solids With Two-Dimensional Damage." Journal of Applied Mechanics 68, no. 4 (January 1, 2001): 528–36. http://dx.doi.org/10.1115/1.1380384.

Full text

Abstract:

A general correlation is derived between macroscopic stresses/strains and microscopic deformation on the damage surfaces for inhomogeneous elastic solids with two-dimensional damage. Assuming linear elastic behavior for the undamaged materials, the macroscopic deformation associated with nonlinear strains, or damage strains, is shown to be the weighted sum of the microscopic deformations on the damage surfaces. For inhomogeneous materials with periodic structures (laminated composites, for example) and various identifiable damage modes, simple relations are derived between the macroscopic deformation and microscopic damage. When the number of identifiable damage modes is less than or equal to the number of relevant measurable macroscopic strains, the correlation can be used to evaluate the damage progression from simple macroscopic stress and strain measurements. The simple case of a unidirectional fiber-reinforced composite under longitudinal load is used to show how the results can help detect and characterize the damage using macroscopic measurements, without resorting to assumptions of detailed microscopic deformation mechanisms.

APA, Harvard, Vancouver, ISO, and other styles

2

Woodward, Nicholas B. "Competitive macroscopic deformation processes." Journal of Structural Geology 21, no. 8-9 (August 1999): 1209–18. http://dx.doi.org/10.1016/s0191-8141(99)00076-0.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Aero, E. L. "Essentially nonlinear theory of microdeformations in medium with periodic structure." Theoretical and Applied Mechanics, no. 28-29 (2002): 1–26. http://dx.doi.org/10.2298/tam0229001a.

Full text

Abstract:

Essentially nonlinear theory of micro and macro deformations of a medium with cardinally rearranging periodic structure is presented using a new model of double continuum with variable local topology. In a frame of proposed model there are two deformation modes (macroscopic and microscopic) when some threshold is reached. Some problems such as twin transitions, catastrophic deformation waves, shock and tilting bifurcation waves are considered. An exact solution describing elasto plastic fragmentation of medium is constructed also when double periodic domain superstructure are formed. There are solid rotons of opposite signs with singular defects between them. They appear in a critical field of macroscopic deformations of pure shear. When this bifurcation point is overcome then dimensions of domains are stabilized. The letter depend on value of macroscopic deformations. Some criterion of global stability is established. .

APA, Harvard, Vancouver, ISO, and other styles

4

Speich, Marco, Wolfgang Rimkus, Markus Merkel, and Andreas Öchsner. "Large Deformation of Metallic Hollow Spheres." Materials Science Forum 623 (May 2009): 105–17. http://dx.doi.org/10.4028/www.scientific.net/msf.623.105.

Full text

Abstract:

Hollow sphere structures are a new group of advanced lightweight materials for multifunctional applications. Within the scope of this paper, the uniaxial deformation behaviour in the regime of large deformations is investigated. Appropriate computational models are developed to account for the deformation mechanisms occurring under high deformations. Macroscopic stress-strain curves are derived and the influence of different material parameters is investigated.

APA, Harvard, Vancouver, ISO, and other styles

5

Gavini, Vikram. "Role of the defect core in energetics of vacancies." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 465, no. 2110 (August 5, 2009): 3239–66. http://dx.doi.org/10.1098/rspa.2009.0136.

Full text

Abstract:

Electronic structure calculations at macroscopic scales are employed to investigate the crucial role of a defect core in the energetics of vacancies in aluminium. We find that vacancy core energy is significantly influenced by the state of deformation at the vacancy core, especially volumetric strains. Insights from the core electronic structure and computed displacement fields show that this dependence on volumetric strains is closely related to the changing nature of the core structure under volumetric deformations. These results are in sharp contrast to mechanics descriptions based on elastic interactions that often consider defect core energies as an inconsequential constant. Calculations suggest that the variation in core energies with changing macroscopic deformations is quantitatively more significant than the corresponding variation in relaxation energies associated with elastic fields. Upon studying the influence of various macroscopic deformations, which include volumetric, uniaxial, biaxial and shear deformations, on the formation energies of vacancies, we show that volumetric deformations play a dominant role in governing the energetics of these defects. Further, by plotting formation energies of vacancies and di-vacancies against the volumetric strain corresponding to any macroscopic deformation, we find that all variations in the formation energies collapse on to a universal curve. This suggests a universal role of volumetric strains in the energetics of vacancies. Implications of these results in the context of dynamic failure in metals through shock-induced spalling are analysed.

APA, Harvard, Vancouver, ISO, and other styles

6

Zaiser, Michael. "Random aspects of macroscopic plastic deformation." Philosophical Magazine Letters 73, no. 6 (June 1996): 369–76. http://dx.doi.org/10.1080/095008396180641.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Taniguchi, Akito, Takatoshi Maeyama, Makoto Uchida, and Yoshihisa Kaneko. "Macroscopic and Microscopic Non-Uniform Deformations of Polycrystalline Pure Copper during Uniaxial Tensile Test with High Stress Gradient." Key Engineering Materials 794 (February 2019): 246–52. http://dx.doi.org/10.4028/www.scientific.net/kem.794.246.

Full text

Abstract:

Metallic materials usually have microscopically heterogeneous structures, such as polycrystalline structures, affecting macroscopic mechanical characteristics. Both macroscopic and microscopic non-uniform deformations of polycrystalline pure copper under a moderate stress gradient were investigated. In this study, macroscopic and microscopic non-uniform deformations under higher stress gradients are investigated. Uniaxial tensile tests using three-curve specimens with different curvatures and grain sizes were performed. In order to evaluate the heterogeneous strain field in the specimen surface, the development of the displacement field was measured using the digital image correlation method (DIC). The stress field was evaluated by coupling the DIC and finite-element methods. In smaller-grain specimens, a strong strain concentration was generated in the minimum cross-section area. Although a strong strain concentration was also confirmed in a larger-grain specimen, the strain field depended not only on the specimen shape but also on the microscopic heterogeneity. This microstructure-driven non-uniform deformation was also observed in the specimen with a larger curvature radius. These results indicated that the macroscopic non-uniform deformation should be estimated by the material parameter related to the microscopic heterogeneity.

APA, Harvard, Vancouver, ISO, and other styles

8

MOHAMMED-AZIZI, B. "NUMERICAL APPROACH OF THE MICROSCOPIC–MACROSCOPIC METHOD." International Journal of Modern Physics C 21, no. 05 (May 2010): 681–94. http://dx.doi.org/10.1142/s0129183110015415.

Full text

Abstract:

A numerical method close to the Strutinsky procedure (but better) is proposed to calculate the deformation energy of nuclei. Quadrupole (triaxial) deformations are considered. Theoretical as well as practical aspects of the method are reviewed in this paper. A complete FORTRAN program illustrates the feasibility of the method. The numerical method employed in this paper avoids the main drawback of the Strutinsky method, that is to say the well known dependency of the results on the inherent two free parameters.

APA, Harvard, Vancouver, ISO, and other styles

9

Xu, Jiankun, Rui Zhou, Dazhao Song, Nan Li, Kai Zhang, and Danyang Xi. "Deformation and damage dynamic characteristics of coal–rock materials in deep coal mines." International Journal of Damage Mechanics 28, no. 1 (November 15, 2017): 58–78. http://dx.doi.org/10.1177/1056789517741950.

Full text

Abstract:

The deformation and damage characteristics of surrounding rock grow gradually with the increase of mining depth, and the mechanical behavior and damage mechanism of coal–rock materials vary greatly. In order to reveal the deformation and damage dynamic characteristics of coal–rock materials in deep mines, the macroscopic deformation characteristics of coal, rock, and concrete samples under uniaxial compression were studied. The macroscopic deformation amount, velocity, and acceleration of different samples were analyzed. The coal and rock samples exhibit regular dynamic characteristics before they lose stability and fail. The axial strain response of the coal samples changes significantly during the compact and elastic deformation stages. Besides, the relationship between the surface damage and the macroscopic deformation of sample was studied by means of visualization and image processing. The macroscopic deformation index of coal–rock materials changes significantly before and after the destabilization and failure. Based on the deformation and failure dynamic characteristics of coal and rock, the evolution rule of deformation critical values was taken as the deformation and destruction stages, which revealed the dynamic characteristics during the deformation and failure process of coal–rock materials in deep mines. The deformation critical values can be used to realize early warning of deformation and fracture of coal and rock materials in deep mines.

APA, Harvard, Vancouver, ISO, and other styles

10

GHERGHESCU, R. A., D. N. POENARU, M. RAPORTARU, B. POPOVICI, and W. GREINER. "CHARGE DENSITY INFLUENCE ON MACROSCOPIC DEFORMATION ENERGY." International Journal of Modern Physics E 19, no. 07 (July 2010): 1411–23. http://dx.doi.org/10.1142/s0218301310015825.

Full text

Abstract:

A formula describing the proton density dependence on macroscopic deformation energy for different fusion-like shape configurations is derived. As a consequence, the influence of intermediary atomic numbers of fusioning nuclei on the macroscopic deformation-dependent terms of the potential energy in the Yukawa-plus-exponential model is studied. For the same target–projectile pair, at the same distance between their centers, macroscopic fusion barriers differ by energy amounts up to 5 MeV.

APA, Harvard, Vancouver, ISO, and other styles

11

Jia, Xiangdong, Kunming Hao, Zhan Luo, and Zhenyu Fan. "Plastic Deformation Behavior of Metal Materials: A Review of Constitutive Models." Metals 12, no. 12 (December 3, 2022): 2077. http://dx.doi.org/10.3390/met12122077.

Full text

Abstract:

The deformation behavior of metal materials in plastic forming is intimately related to deformation conditions, which are greatly affected by deformation rate, forming temperature, and plastic variables. Macroscopic mechanical properties research is an important basis and technical means to analyze the process parameters and deformation process of metal plastic forming. Therefore, to reveal the influence mechanism of macroscopic mechanical properties of metal materials, and establish material constitutive models under different deformation conditions, it is of great significance to choose reasonable forming parameters and prevent forming defects. There are substantial variances in the macroscopic mechanical characteristics of different materials in the deformation process. In order to accurately predict its deformation behavior, the phenomenological constitutive model, the microscopic constitutive model reflecting the microscopic deformation mechanism, and the artificial neural network constitutive model based on the neural network were constructed respectively on the basis of macroscopic mechanical tests and microscopic microstructure tests. On the basis of the existing research results, the advantages and disadvantages of phenomenological constitutive model, microscopic constitutive model, and neural network constitutive model are compared and analyzed, respectively. The research results of this paper will provide support for the selection of constitutive models for reasonably predicting the deformation behavior of metal materials.

APA, Harvard, Vancouver, ISO, and other styles

12

IMATANI, Shoji, and Kosuke SAKURAI. "Macroscopic Deformation Behavior of Random Skeletal Structures." Journal of the Society of Materials Science, Japan 68, no. 11 (November 15, 2019): 805–11. http://dx.doi.org/10.2472/jsms.68.805.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Zuev, L. B. "Macroscopic Physics of Plastic Deformation of Metals." Uspehi Fiziki Metallov 16, no. 1 (March 1, 2015): 35–60. http://dx.doi.org/10.15407/ufm.16.01.035.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Urbanec, M., E. Běták, and Z. Stuchlík. "Macroscopic properties of neutron stars including deformation." Journal of Physics: Conference Series 337 (February 8, 2012): 012021. http://dx.doi.org/10.1088/1742-6596/337/1/012021.

Full text

APA, Harvard, Vancouver, ISO, and other styles

15

Butler, James P., Hiroshi Miki, Stephanie Squarcia, Rick A. Rogers, and John L. Lehr. "Effect of macroscopic deformation on lung microstructure." Journal of Applied Physiology 81, no. 4 (October 1, 1996): 1792–99. http://dx.doi.org/10.1152/jappl.1996.81.4.1792.

Full text

Abstract:

Butler, James P., Hiroshi Miki, Stephanie Squarcia, Rick A. Rogers, and John L. Lehr. Effect of macroscopic deformation on lung microstructure. J. Appl. Physiol.81(4): 1792–1799, 1996.—Using an anisotropic theory of diffuse light scattering in lungs, we measured the fractional changes in geometric mean linear intercepts in orthogonal directions when freshly excised rabbit lungs were subjected to isovolume uniaxial strains. Results from the optical technique were compared with morphometric estimates of fractional changes in mean linear intercepts from the same strained and unstrained (control) lobes, with the conclusion that diffuse light scattering is adequate to estimate changes in mean free paths in different directions. We compared optical estimates of fractional changes in mean linear intercepts with the macroscopic strain field measured by displacements of pleural markers; this relationship did not significantly differ from the line of identity. We conclude that the microscopic strain field is closely matched to the macroscopic strain field during uniaxial distortion. This suggests that surface reorientation may not play a large role in the origin of the low shear modulus of the lung, but this cannot be definitively stated without comparison of these experimental results to specific model predictions of the changes in mean linear intercepts in shear deformation.

APA, Harvard, Vancouver, ISO, and other styles

16

Wilmanski, Krzysztof. "Macroscopic theory of evolution of deformation textures." International Journal of Plasticity 8, no. 8 (January 1992): 959–75. http://dx.doi.org/10.1016/0749-6419(92)90045-e.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

UCHIDA, MAKOTO, and NAOYA TADA. "MULTISCALE COMPUTATIONAL EVALUATION OF ELASTO-VISCOPLASTIC DEFORMATION BEHAVIOR OF AMORPHOUS POLYMER CONTAINING MICROSCOPIC HETEROGENEITY DURING UNIAXIAL TENSILE TEST." Journal of Multiscale Modelling 02, no. 03n04 (September 2010): 235–55. http://dx.doi.org/10.1142/s1756973710000394.

Full text

Abstract:

The two-scale elasto-viscoplastic deformation behavior of amorphous polymer was investigated using the large deformation finite element homogenization method. In order to enable a large time increment for the simulation step in the plastic deformation stage, the tangent modulus method is introduced into the nonaffine molecular chain network theory, which is used to represent the deformation behavior of pure amorphous polymer. Two kinds of heterogeneous microstructures were prepared in this investigation. One was the void model, which contains uniformly or randomly distributed voids, and the other was the heterogeneous strength (HS) model, which contains a distribution of initial shear strength. In the macroscopic scale, initiation and propagation processes of necking during uniaxial tension were considered. The macroscopic nominal stress–strain relation was strongly characterized by the volume fraction and distribution of voids for the void model and by the width of the strength distribution for the HS model. Non-uniform deformation behaviors in microscopic and macroscopic scales are closely related to each other for amorphous polymers because continuous stretching and hardening in the localized zone of the microstructure brings about an increase in macroscopic deformation resistance. Furthermore, computational results obtained from the homogenization model are compared to those obtained from the full-scale finite element model, and the effect of the scale difference between microscopic and macroscopic fields is discussed.

APA, Harvard, Vancouver, ISO, and other styles

18

Yang, Qing Sheng, and Fang Xu. "Effective Hyperelastic Behaviour of Fiber Reinforced Polymer Composite Materials." Key Engineering Materials 334-335 (March 2007): 473–76. http://dx.doi.org/10.4028/www.scientific.net/kem.334-335.473.

Full text

Abstract:

The macroscopic hyperelastic behavior of fiber reinforced polymer composites is studied using the micromechanical model and finite deformation theory. It is assumed that the fiber and matrix are hyperelastic media and undergoing finite deformation. The local fields of a representative volume element are calculated by the hyperelastic finite element method. Then an averaging procedure is used to find the homogenized stress and strain and the macroscopic curves of stress-strain are obtained. The several microstructural parametric effects on the macroscopic hyperelastic behavior are considered. The numerical examples show the hyperelastic behavior and deformation of the composites.

APA, Harvard, Vancouver, ISO, and other styles

19

Liu, Cai Ping, and Qing Quan Duan. "Macroscopic and Mesoscopic Large Deformation Measurement Methods for Metal Materials." Advanced Materials Research 146-147 (October 2010): 1769–74. http://dx.doi.org/10.4028/www.scientific.net/amr.146-147.1769.

Full text

Abstract:

The stress-strain curve in the large plastic deformation process is always not available due to the strain gauge deficiencies in large deformation measurement. Considering this problem, digital marker identification technique is used to measure large deformation of Steel Q235 with images taken by with charge-coupled device. Then together with the deformation measured by traditional stain gauge at small deformation stage, the total stress and strain curve is obtained at macroscale. The mesoscopic deformation is measured by a material testing system assembled with scanning electronic microscope. The images from the initial stage to the rupture stage are captured synchronously. What’s more, using the grid method, the strain and rotation in rational mechanics is analyzed.

APA, Harvard, Vancouver, ISO, and other styles

20

DUDEK, J., K. MAZUREK, and B. NERLO-POMORSKA. "SEARCH FOR THE TRI-AXIAL HEXADECAPOLE-DEFORMATION EFFECTS IN TRANS-ACTINIDAE NUCLEI." International Journal of Modern Physics E 14, no. 03 (April 2005): 383–88. http://dx.doi.org/10.1142/s0218301305003168.

Full text

Abstract:

We have performed calculations of the nuclear potential energies in a 5-dimensional space of deformation parameters including α20, α22, α40, α42 and α44 multipole deformations by using the macroscopic-microscopic method. The energy expression contains the macroscopic term (in our case in the form of the Lublin Strasbourg Drop – LSD) and the microscopic terms of the Strutinsky shell energy and projected BCS pairing energy. The single-particle energies are obtained from the classical mean-field potential as well as from the correspondig Dirac relativistic realisation of the mean-field, both parametrised with the help of the deformed Woods-Saxon forms. Our resuls are compared to the selfconsistent Hartree Fock Bogolubov method with the D1S Gogny force.

APA, Harvard, Vancouver, ISO, and other styles

21

Mathur, K. K., and P. R. Dawson. "Texture Development During Wire Drawing." Journal of Engineering Materials and Technology 112, no. 3 (July 1, 1990): 292–97. http://dx.doi.org/10.1115/1.2903326.

Full text

Abstract:

The development of deformation induced anisotropy in wire drawing operations is modeled with a finite element formulation that incorporates a polycrystalline plasticity model to describe the metal anisotropy. An aggregrate of grains is assumed to underly every material point on the continuum scale. The averaged response of an aggregate defines the macroscopic behavior of the corresponding material point, which is used in the finite element formulation to solve the boundary value problem corresponding to wire drawing. Macroscopic deformations imposed on the aggregate cause changes in the relative orientation of grains, thereby producing texture and associated anisotropy. Textures predicted from the drawing of aluminum wire are presented with special attention to the variations in texture from redundant deformations.

APA, Harvard, Vancouver, ISO, and other styles

22

Khon, Yu A., and L. B. Zuev. "Relaxation mode of macroscopic plastic deformation in metals." Izvestiya vysshikh uchebnykh zavedenii. Fizika, no. 9 (2020): 86–88. http://dx.doi.org/10.17223/00213411/63/9/86.

Full text

Abstract:

The relaxation of elastic energy during macroscopic plastic deformation in a strict formulation is determined by the solutions of the system of nonlinear equations of mechanics of a deformable solid. Using the methods of the theory of nonlinear systems, a nonlinear parabolic equation is obtained for the amplitude of an unstable mode, which describes plastic deformation at large spatial and temporal scales.

APA, Harvard, Vancouver, ISO, and other styles

23

Khon, Yu A., and L. B. Zuev. "Relaxation Mode of Macroscopic Plastic Deformation in Metals." Russian Physics Journal 63, no. 9 (January 2021): 1545–47. http://dx.doi.org/10.1007/s11182-021-02204-w.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Takeuchi, S. "Onset of macroscopic deformation. Microscopic processes (Moderator's Comment)." Revue de Physique Appliquée 23, no. 4 (1988): 405–8. http://dx.doi.org/10.1051/rphysap:01988002304040500.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Evans, Jack D., and François-Xavier Coudert. "Macroscopic Simulation of Deformation in Soft Microporous Composites." Journal of Physical Chemistry Letters 8, no. 7 (March 23, 2017): 1578–84. http://dx.doi.org/10.1021/acs.jpclett.7b00397.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Korbel, A., and P. Martin. "Microscopic versus macroscopic aspect of shear bands deformation." Acta Metallurgica 34, no. 10 (October 1986): 1905–9. http://dx.doi.org/10.1016/0001-6160(86)90249-x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Thurn, Jeremy, and Robert F. Cook. "Indentation-induced deformation at ultramicroscopic and macroscopic contacts." Journal of Materials Research 19, no. 1 (January 2004): 124–30. http://dx.doi.org/10.1557/jmr.2004.19.1.124.

Full text

Abstract:

Depth-sensing indentation at ultramicroscopic and macroscopic contacts (“nanoindentation” and “macroindentation,” respectively) was performed on four brittle materials (soda-lime glass, alumina titanium carbide, sapphire, and silicon) and the resulting load–displacement traces examined to provide insight to the elastic and plastic deformation scaling with contact size. The load–displacement traces are examined in terms of the unloading stiffness, the energies deposited during loading and recovered on unloading, and the effect of the indenter tip radius on the loading curve. The results of the analyses show that the elastic and plastic deformation during loading and unloading is invariant with the scale of the contact, and the unloading curve is best described by neither a conical tip nor a paraboloid of revolution, but of some compromise.

APA, Harvard, Vancouver, ISO, and other styles

28

Dimitrienko, Yu, S. Karimov, and D. Kolzhanova. "Coupled micro-macroscopic modeling of layered composites with finite deformations." E3S Web of Conferences 376 (2023): 01030. http://dx.doi.org/10.1051/e3sconf/202337601030.

Full text

Abstract:

A coupled micro- and macroscopic modeling of an incompressible layered composite material under finite deformations is performed based on the asymptotic homogenization method and universal semi-linear models. The deformation diagrams of the periodicity cell are calculated. A method for searching for effective transversally isotropic properties of LCM based on the obtained diagrams is considered. Cylindrical bending of an LCM plate is simulated using the model of a transversally isotropic medium. The microstresses in the periodicity cell are calculated based on the homogenized stresses.

APA, Harvard, Vancouver, ISO, and other styles

29

Riku, Isamu, and Koji Mimura. "Numerical Evaluation of Micro- to Macroscopic Mechanical Behavior of Plastic Foam." Key Engineering Materials 340-341 (June 2007): 1025–30. http://dx.doi.org/10.4028/www.scientific.net/kem.340-341.1025.

Full text

Abstract:

In this study, we employ the two-dimensional homogenization model based on molecular chain network theory to investigate the micro- to macroscopic mechanical behavior of plastic foam under macroscopic uniform compression. A parametric study is performed to quantify the effect of a characteristic value of matrix, distribution and initial volume fraction of voids, and the macroscopic triaxiality of loading condition on the deformation behavior of the foam. The results suggest that the onset of localized shear band at the ligament between voids together with the microscopic buckling of the ligament leads to the macroscopic yield of the foam. The initial modulus and the macroscopic yield stress of the foam have no dependence on the characteristic value of matrix. Furthermore, as the microscopic buckling of the ligament is promoted in case of high initial volume fraction of voids and high triaxiality loading condition, the macroscopic yield point appears at early deformation stage. After the macroscopic yield, macroscopic strain hardening appears in the macroscopic response and a remarkable strain hardening is shown in case of high initial volume fraction of voids and high triaxiality loading condition due to the considerable increase of the density of the foam in these cases.

APA, Harvard, Vancouver, ISO, and other styles

30

Maruyama, Kazuya, Xue Zheng Yue, and Koichi Kitazono. "Evaluation of Local Strain Distribution during Compressive Deformation of Open-Cell Porous Metals." Materials Science Forum 933 (October 2018): 169–73. http://dx.doi.org/10.4028/www.scientific.net/msf.933.169.

Full text

Abstract:

Relationship between the macroscopic and local strains of porous metals is examined by microstructural observation. Open-cell porous titanium with 60% porosity was compressed up to 30% macroscopic strain at room temperature. Open-cell porous nickel with 95% porosity was compressed up to 40% macroscopic strain at room temperature. Local strains in cell walls of both porous titanium and nickel were evaluated by electron backscatter diffraction (EBSD). Absolute value of the local strain increased with increasing the macroscopic strain and it is smaller than that of macroscopic strain. In addition, the value of the local strain at the cell junctions was larger than that of the center of cell struts.

APA, Harvard, Vancouver, ISO, and other styles

31

Uchida, Makoto, and Naoya Tada. "Computational Simulation of Micro- to Macroscopic Deformation Behavior of Cavitated Rubber Blended Amorphous Polymer Using Second-Order Homogenization Method." Key Engineering Materials 626 (August 2014): 74–80. http://dx.doi.org/10.4028/www.scientific.net/kem.626.74.

Full text

Abstract:

To evaluate the effect of the size of the microstructure on the mechanical property of the cavitated rubber blended (voided) amorphous polymer, the FEM simulation based on the rate form second-order homogenization method, in which rates of the macroscopic strain and strain gradient are given to the microstructure, was performed. Computational simulations of micro-to macroscopic deformation behaviors of amorphous polymers including different sizes and volume fractions of the voids were performed. Non-affine molecular chain network theory was employed to represent the inelastic deformation behavior of the amorphous polymer matrix. With the increase in the volume fraction of the void, decrease and periodical fluctuation of stress and localized deformation in the macroscopic field were observed, and were more emphasized with the increase in the size of the void. These results were closely related to the non-uniform deformation and volume increase of the void in the microscopic field.

APA, Harvard, Vancouver, ISO, and other styles

32

Xiao, Peiwei, Bo Qian, Peng Jiang, Nuwen Xu, and Biao Li. "Deformation Forecasting of Surrounding Rock Mass Based on Correlation between Frequency and Fracture Scale of Microseismicity." Advances in Civil Engineering 2018 (July 10, 2018): 1–13. http://dx.doi.org/10.1155/2018/4037402.

Full text

Abstract:

The macroscopic deformation and failure of engineering rock mass may occur as a result of evolution and breakdown of its internal microfracture. Therefore, the macroscopic state of rock mass can be obtained from fracture scale of microfracture in real time. To assess instability and predict macroscopic deformation and failure of engineering rock mass, a time-frequency analysis technique based on S transform was proposed to investigate microseismic waveform and reveal the correlation between macroscopic deformation failure and microseismic frequency characteristics of engineering rock mass in combination with fracture scale. To minimize the influence of external factors on parameters calculated, a significant amount of microseismic data from three large-scale hydropower projects in southwestern China was collected as the statistical sample. The analysis of correlation between fracture scale and frequency characteristics of microseismic events was carried out based on the statistical sample. Combining with microseismic data and multipoint extensometers in the underground powerhouse of the Houziyan hydropower station, engineering verification was conducted. The result shows that the high-frequency components decrease and microseismic signals display low-frequency characteristic as the fracture scale increases; the microseismic high-frequency components decreased at first and then increased during the deformation process of surrounding rock mass, and the frequency of microseismic events shifts from high band to a lower one before deformation.

APA, Harvard, Vancouver, ISO, and other styles

33

Lin, Xiao Ping, Yun Dong, and Lian Wei Yang. "Macroscopy Lattice Deformation of Martensitic Transformation in Fe-Based Shape Memory Alloy." Applied Mechanics and Materials 148-149 (December 2011): 1240–43. http://dx.doi.org/10.4028/www.scientific.net/amm.148-149.1240.

Full text

Abstract:

Macroscopic lattice deformation of martensitic transformation and shape memory effect (SME) were studied by atom force microscopy (AFM), X-ray diffraction and so on. The results showed that stress induced martensitic surface relief was “N”-shaped. The surface relief was parallel distribution when deformation was less than 6%. When relief became to intercross, its height and width were far less than parallel relief in same deformation. Superior heat-recovery was discovered in parallel surface relief. The recovery ratio was very low in intercrossed relief. The macroscopic lattice deformation descends in virtue of relief intercrossed, then recovery process was forbidden, so that recovery ratio was descent.

APA, Harvard, Vancouver, ISO, and other styles

34

Cao, Wengui, Xin Tan, Chao Zhang, and Min He. "Constitutive model to simulate full deformation and failure process for rocks considering initial compression and residual strength behaviors." Canadian Geotechnical Journal 56, no. 5 (May 2019): 649–61. http://dx.doi.org/10.1139/cgj-2018-0178.

Full text

Abstract:

A constitutive model with capacity to simulate the full deformation and failure process for rocks considering initial compression and residual strength behaviors is discussed in this paper. The rock was assumed to consist of the initial voids portion and the solid skeleton portion. The full deformation model of rocks can be established by the consideration of the macroscopic deformation of rocks and the microscopic deformations of the two different portions based on the statistical damage theory. Comparisons between the experimental data from triaxial compression tests and calculated results show that the proposed constitutive model provided a good prediction of the full deformation and failure process, including the effects of initial void compression, stiffness degradation, strain hardening–softening, and residual strength.

APA, Harvard, Vancouver, ISO, and other styles

35

Vogel, Sven C., Helmut Reiche, and Donald W. Brown. "High pressure deformation study of zirconium." Powder Diffraction 22, no. 2 (June 2007): 113–17. http://dx.doi.org/10.1154/1.2737459.

Full text

Abstract:

In situ deformation studies of polycrystalline materials using diffraction are an established method to understand elastic and plastic deformation of materials. Studies of active deformation mechanisms, the interplay of deformation with texture, and ultimately the development of predictive capabilities for deformation modeling are an active field of research. Parameters studied by diffraction are typically lattice strains and texture evolution, which coupled with the macroscopic flow curve allow for improved understanding of the micro-mechanics of deformation. We performed a study of the uniaxial deformation of Zircaloy-2 at 2 GPa at the 13-BM-D beamline at the Advanced Photon Source. The deformation-DIA apparatus generates a confining hydrostatic pressure using a cubic anvil setup. Two differential rams allow an increase (compressive load) or decrease (tensile load) of the uniaxial straining in the vertical direction, allowing studies of plastic deformation at high pressures. In this paper, we describe how macroscopic strains, hydrostatic pressure, and uniaxial strains are derived and present some brief results.

APA, Harvard, Vancouver, ISO, and other styles

36

Morita, S., H. Yasuda, T. Nagira, C. M. Gourlay, M. Yoshiya, and A. Sugiyama. "Macroscopic modelling of semisolid deformation for considering segregation bands induced by shear deformation." IOP Conference Series: Materials Science and Engineering 33 (July 3, 2012): 012053. http://dx.doi.org/10.1088/1757-899x/33/1/012053.

Full text

APA, Harvard, Vancouver, ISO, and other styles

37

Ben Haj Slama, Meriem, Nabila Maloufi, Julien Guyon, Slim Bahi, Laurent Weiss, and Antoine Guitton. "In Situ Macroscopic Tensile Testing in SEM and Electron Channeling Contrast Imaging: Pencil Glide Evidenced in a Bulk β-Ti21S Polycrystal." Materials 12, no. 15 (August 4, 2019): 2479. http://dx.doi.org/10.3390/ma12152479.

Full text

Abstract:

In this paper, we report the successful combination of macroscopic uniaxial tensile testing of bulk specimen combined with In situ dislocation-scale observations of the evolution of deformation microstructures during loading at several stress states. The dislocation-scale observations were performed by Accurate Electron Channeling Contrast Imaging in order to follow the defects evolution and their interactions with grain boundaries for several regions of interest during macroscopic loading. With this novel in situ procedure, the slip systems governing the deformation in polycrystalline bulk β-Ti21S are tracked during the macroscopic uniaxial tensile test. For instance, curved slip lines that are associated with “pencil glide” phenomenon and tangled dislocation networks are evidenced.

APA, Harvard, Vancouver, ISO, and other styles

38

Шабуневич, В., and А. Шабуневич. "К ВОПРОСУ ФИЗИЧЕСКОГО ОБОСНОВАНИЯ КРИТЕРИЕВ ЕДИНОЙ ТЕОРИИ ФИЗИКИ." EurasianUnionScientists 6, no. 12(81) (January 18, 2021): 47–55. http://dx.doi.org/10.31618/esu.2413-9335.2020.6.81.1175.

Full text

Abstract:

With the help of harmonic analysis of different-scale finite element models of cubic and spherical cells, a physical substantiation of possible criteria for a unified theory of physics is presented, which consists in the fact that both with a decrease in cells from macroscopic to mesostatic and down to microscopic levels of deformation, and with an increase in cells from macroscopic to megascopic level, periodic changes in the number of resonance peaks of the deformation parameters of the cells are observed, which can explain various characteristic physical phenomena at different scale levels of deformation.

APA, Harvard, Vancouver, ISO, and other styles

39

Onuki, Yusuke, and Shigeo Sato. "Anomalous Twinning as the Macroscopic Deformation Mechanism for AZ31 Magnesium Alloy." Key Engineering Materials 810 (July 2019): 95–100. http://dx.doi.org/10.4028/www.scientific.net/kem.810.95.

Full text

Abstract:

In order to study the plastic deformation mechanism of AZ31 magnesium alloy, in situ texture measurement during uniaxial tensile deformation is conducted by using neutron diffraction. The specimen is prepared from a rolled sheet so that the deformation axis is parallel to the rolling direction. By increasing strain, the alignment of <10-10> along the tensile axis is strengthened, which is due to the activation of the prism slip system. The basal pole concentration at the prior sheet normal direction is slightly decreased by the deformation and the new texture component is formed at the transvers direction. This can be understood by activation of the {10-12} tension twinning. These results indicate that the tension twinning plays an important role even when the tensile deformation is applied parallel to the basal plane.

APA, Harvard, Vancouver, ISO, and other styles

40

Dubois, Matthieu, Don Brown, Bjørn Clausen, Ahmed Addad, and Alain Lodini. "Study of Superelastic Behavior of CuAlBe Shape Memory Alloy by Neutron Diffraction." Solid State Phenomena 216 (August 2014): 194–99. http://dx.doi.org/10.4028/www.scientific.net/ssp.216.194.

Full text

Abstract:

The aim of this work is to understand the evolutions of the β1metastable austenite phase of a CuAlBe Shape Memory Alloy at macroscopic and microscopic scales under mechanical solicitation by neutron diffraction. The tensile specimen, taken in the raw material is subjected to superelastic cycles at room temperature on SMARTS diffractometer. Before loading, the mater ial is fully austenitic. During loading, after elastic deformation of austenite, phase transformation starts, martensite variants appear. The material follows a law of pseudo elastic behavior. At the end of the first mechanical cycle after unloading, the macroscopic curve does not fully return into its original point. A macroscopic deformation is observed. The evolution of first order microdeformations during mechanical cycles shows a large deformation of {400} plane family. This deformation is linked to the presence of <001> partial fibber characterizing the crystallographic texture of the material after elaboration. The FWHM of the (400) diffraction peak is also largely increased during loading. This increase is the signature of the generation of stacking faults during the transformation of β1metastable austenite into β1martensite.

APA, Harvard, Vancouver, ISO, and other styles

41

Kardan, A., and S. Nejati. "Nonaxial hexadecapole deformation effects on the fission barrier." International Journal of Modern Physics E 25, no. 08 (August 2016): 1650047. http://dx.doi.org/10.1142/s0218301316500476.

Full text

Abstract:

Fission barrier of the heavy nucleus [Formula: see text]Cf is analyzed in a multi-dimensional deformation space. This space includes two quadrupole ([Formula: see text]) and three hexadecapole deformation ([Formula: see text]) parameters. The analysis is performed within an unpaired macroscopic–microscopic approach. Special attention is given to the effects of the axial and non-axial hexadecapole deformation shapes. It is found that the inclusion of the nonaxial hexadecapole shapes does not change the fission barrier heights, so it should be sufficient to minimize the energy in only one degree of freedom in the hexadecapole space [Formula: see text]. The role of hexadecapole deformation parameters is also discussed on the Lublin–Strasbourg drop (LSD) macroscopic and the Strutinsky shell energies.

APA, Harvard, Vancouver, ISO, and other styles

42

CÂRJAN, N., K. SIWEK-WILCZYŃSKA, I. SKWIRA-CHALOT, and J. WILCZYŃSKI. "MACROSCOPIC DYNAMICAL DESCRIPTION OF ROTATING Au + Au SYSTEM." International Journal of Modern Physics E 17, no. 01 (January 2008): 53–59. http://dx.doi.org/10.1142/s0218301308009549.

Full text

Abstract:

Events with more than two heavy fragments have been abundantly observed in heavy-ion semi-peripheral (fission-like) reaction 197 Au +197 Au at 15 MeV/nucleon. This raised interesting questions about their origin and about the time-scale at which they occur. As a possible explanation of this process, the surface instability of the cylindrical neck that is formed along the path from contact to reseparation of the rotating Au + Au system is investigated in the present paper. For this purpose the Los Alamos finite-range macroscopic dynamical model was used. The calculations were performed at relatively high angular momenta, L = 100 to 300 ħ, for two types of dissipation mechanisms: two-body viscosity and one-body dissipation. Various initial nuclear deformations and initial kinetic energies in the fission direction were considered. The resulting dynamical evolution in the multidimensional deformation space always led to multifragment scission configurations suggesting that ternary and quaternary break-up can occur during the heavy-ion reaction studied.

APA, Harvard, Vancouver, ISO, and other styles

43

Černý, Michal, Michal Šustr, and Petr Dostál. "Testing of Macroscopic Hardness by Acoustic Response." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 64, no. 3 (2016): 751–58. http://dx.doi.org/10.11118/actaun201664030751.

Full text

Abstract:

Static measurement of macroscopic hardness (hereinafter macrohardness) of metal materials by using indentation testing is accompanied by deformation in the vicinity of the indenter. Its indenting in a material, monitoring of consequent acoustic response during plastic deformation and interconnection with the records of acoustic emission (hereinafter AE) is the aim of this submitted paper. This non-destructive testing (NDT) method concentrates on the comparison of an acoustic event and the result of the hardness measurement of steels with different hardness values and for a specimen made from steel and tungsten carbide. The aforementioned measurements were conducted concurrently at two workplaces and resulted in very good conformance of records for hard materials. The result obtained confirms the possibility of carrying out correlation between the results of measuring hardness and those obtained from the hits at the acoustic emission testing.

APA, Harvard, Vancouver, ISO, and other styles

44

Hori, Muneo. "Micromechanical Analyses on Granular Column Formation and Macroscopic Deformation." Soils and Foundations 36, no. 4 (December 1996): 71–80. http://dx.doi.org/10.3208/sandf.36.4_71.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Bengus, V. "Scale transition from single glide bands to macroscopic deformation." Le Journal de Physique IV 11, PR5 (September 2001): Pr5–237—Pr5–241. http://dx.doi.org/10.1051/jp4:2001529.

Full text

APA, Harvard, Vancouver, ISO, and other styles

46

Yager, D., H. Feldman, and Y. C. Fung. "Microscopic vs. macroscopic deformation of the pulmonary alveolar duct." Journal of Applied Physiology 72, no. 4 (April 1, 1992): 1348–54. http://dx.doi.org/10.1152/jappl.1992.72.4.1348.

Full text

Abstract:

The stretch of the perimeters of alveolar ducts was measured at the surface of saline-filled specimens of human and dog lung parenchyma that were stretched biaxially. The microscopic stretch of these ducts was measured at several levels of isotropic biaxial macroscopic stretch of the parenchyma with stretch ratio (lambda x = lambda y) in the range of 1.20–1.40, which roughly corresponds to tidal breathing in humans and dogs. Alveolar walls were found to be load-carrying elements in the saline-filled lung, as seen by their straightness at all levels of stretch. Quantitatively, let l, A, L, and S denote, respectively, the duct perimeter length and area and the parenchymal target perimeter and area in the deformed state and lo, Ao, Lo, and So the corresponding variables in the undeformed state. The microscopic stretch ratio of the ducts (l/lo) was found to be approximately 4% larger than the macroscopic stretch ratio (L/Lo) in human lung and approximately 10% larger in dog lung. The microscopic area ratio of the ducts (A/Ao) was found to be approximately 10% larger than the macroscopic area ratio (S/So) in human lung and approximately 22% larger in dog lung. Ducts within human parenchyma were seen to be about twice as stiff as ducts within dog parenchyma over the range of macroscopic stretch studied. This correlates with the volume fractions of collagen and elastin being higher in the human lung than in dog lung. The observed nonuniformity in strain field at the microstructural level suggests the need to include a force balance between alveolar ducts and septal walls when modeling the mechanics of saline-filled parenchyma.

APA, Harvard, Vancouver, ISO, and other styles

47

Ananthan, V. S., and E. O. Hall. "Macroscopic aspects of Lüders band deformation in mild steel." Acta Metallurgica et Materialia 39, no. 12 (December 1991): 3153–60. http://dx.doi.org/10.1016/0956-7151(91)90049-7.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Sakamoto, Hidetoshi, Jian Shi, Yoshifumi Ohbuchi, and Mitsuharu Yamamoto. "Evaluation of Plastic Deformation and Fracture Behaviors by Thermal Image Technique." Key Engineering Materials 462-463 (January 2011): 756–61. http://dx.doi.org/10.4028/www.scientific.net/kem.462-463.756.

Full text

Abstract:

Failure of mechanical members largely depends on the size and the development of plastic deformation from the strain concentration parts. In order to evaluate this plastic deformation of mechanical members, we pay attention to the surface temperature that is generated by plastic deformation. Most of the plastic energy exhausted by plastic deforming is converted into heat. Therefore, the heat generation represents the macroscopic plastic deformed intensity. In this report, the tensile deformation tests by using the plate specimen with a center crack were performed and the distributions of surface temperature under the plastic deformation and crack propagation were measured by the thermocouple and the infrared thermo camera. Furthermore, FE elasto-plastic analysis couples with transient heat conduction was performed. The analytical results were good agreement with the experimental ones and it was shown that the infrared thermography method was effective non-contact measurement system as the macroscopic evaluation of the plastic deformation.

APA, Harvard, Vancouver, ISO, and other styles

49

Dimitrienko, Yu, E. Gubareva, and M. Cherkasova. "Modeling of effective elastic-plastic properties of layered composites with a periodic structure in the framework of the anisotropic flow theory." E3S Web of Conferences 376 (2023): 01036. http://dx.doi.org/10.1051/e3sconf/202337601036.

Full text

Abstract:

The article is devoted to the development of a method for constructing theoretical strain diagrams. The method is based on the use of a model of effective constitutive relations for approximating the deformation diagrams of layered composites obtained using the asymptotic averaging method. To find the elastic constants of the model of a transversally isotropic composite, the method of minimizing the deviation of the approximation deformation diagrams from the diagrams obtained by the asymptotic homogenization (AH) method is used for a series of standard problems of deformation at small deformations. Minimization problems were solved using the Hooke-Jeeves method. The results of numerical simulation by the proposed method for layered composites are presented, which showed good approximation accuracy, which is achieved due to the proposed method for separating the coupled problems of micro- and macroscopic deformation.

APA, Harvard, Vancouver, ISO, and other styles

50

Gnatenko, Kh P., and V. M. Tkachuk. "Kinetic energy properties and weak equivalence principle in a space with generalized uncertainty principle." Modern Physics Letters A 35, no. 13 (February 20, 2020): 2050096. http://dx.doi.org/10.1142/s0217732320500960.

Full text

Abstract:

A space with deformed commutation relations for coordinates and momenta leading to generalized uncertainty principle (GUP) is studied. We show that GUP causes great violation of the weak equivalence principle for macroscopic bodies, violation of additivity property of the kinetic energy, dependence of the kinetic energy on composition, great corrections to the kinetic energy of macroscopic bodies. We find that all these problems can be solved in the case of arbitrary deformation function depending on momentum if parameter of deformation is proportional inversely to squared mass.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Macroscopic deformation'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles