Results 261 to 270 of about 2,346 (291)

Geometrically necessary boundaries, incidental dislocation boundaries and geometrically necessary dislocations

Scripta Materialia, 2003
Abstract The concept of statistically stored and geometrically necessary dislocations is discussed in terms of observed deformation microstructures subdivided by incidental dislocation and geometrically necessary boundaries. This discussion is illustrated by examples of microstructures formed under conditions of homogeneous and nonhomogeneous ...
D.A Hughes, N Hansen, D.J Bammann
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Geometrically Necessary Dislocations in Deformed Martensitic Steel

Advanced Materials Research, 2014
Effect of a size of closed structural formation on accumulation of dislocation density and its components at plastic deformation is studied. Main attention is given to a role of a division of boundaries of a different type. Structural formation sizes are determined and different parameters of structure defining micro-and mezolevel at development of ...
Nina Koneva, Natal'ya Popova, Marina Fedorischeva, Eduard Kozlov   +3 more
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Where are the geometrically necessary dislocations accommodating small imprints?

Journal of Materials Research, 2009
Electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM) analyses of small indentations in copper single crystals exhibit only slight changes of the crystal orientation in the surroundings of the imprints. Far-reaching dislocations might be the reason for these small misorientation changes.
M. Rester, C. Motz, R. Pippan
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Experimental lower bounds on geometrically necessary dislocation density

International Journal of Plasticity, 2010
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Kysar, J. W., Saito, Y., Oztop, M. S., Lee, D., Huh, W. T.   +4 more
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Stress fields of finite-size dislocation walls and prediction of back stress induced by geometrically necessary dislocations at grain boundaries

Journal of the Mechanics and Physics of Solids, 2020
International audienceAt low strain, geometrically necessary dislocations (GND) confined in the close vicinity of grain boundaries can be approximated as a dislocation wall structure called a GND facet.
Maoyuan Jiang, Ghiath Monnet, B Devincre   +2 more
exaly   +2 more sources

Crystal plasticity model with enhanced hardening by geometrically necessary dislocation accumulation

Journal of the Mechanics and Physics of Solids, 2002
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Evers, L.P., Parks, D.M., Brekelmans, W.A.M., Geers, M.G.D.   +3 more
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Experimentally determined content of a geometrically necessary dislocation boundary in copper

Acta Materialia, 2004
Abstract Weak beam and stereo transmission electron microscopy (TEM) were used to analyze the dislocation content of a crystallographic geometrically necessary dislocation boundary (GNB) in rolled copper. The GNB is oriented close to the ( 1 1 1) slip plane and is composed primarily of dislocations from the three highest stressed slip ...
Rodney J McCabe, Amit Misra, Terence E Mitchell   +2 more
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Finite element analysis of geometrically necessary dislocations in crystal plasticity

International Journal for Numerical Methods in Engineering, 2012
SUMMARYWe present a finite element method for the analysis of ductile crystals whose energy depends on the density of geometrically necessary dislocations (GNDs). We specifically focus on models in which the energy of the GNDs is assumed to be proportional to the total variation of the slip strains.
Hurtado, Daniel E., Ortiz, Michael
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Gradients of geometrically necessary dislocations from white beam microdiffraction

Materials Science and Engineering: A, 2005
Abstract Variations in the local crystallographic orientation due to the presence of geometrically necessary dislocations and dislocation boundaries smear the distribution of intensity near Laue reflections. Here, some simple model distributions of geometrically necessary dislocations, GNDs, are used to estimate the dislocation tensor field from the ...
R.I. Barabash, G.E. Ice, J.W.L. Pang
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Characterizing geometrically necessary dislocations using an elastic–plastic decomposition of Laplace stretch

Zeitschrift für angewandte Mathematik und Physik, 2020
The paper studies the geometric dislocation density tensor and Burgers vector using an elastic-plastic decomposition of Laplace stretch which arises from a QR decomposition of the deformation gradient and allows for direct experimental measurement. The geometric dislocation density tensor is obtained using the classical argument of failure of a Burgers
Sandipan Paul, Alan D. Freed
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