Results 251 to 260 of about 52,903 (306)

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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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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The J-integral and geometrically necessary dislocations in nonuniform plastic deformation

International Journal of Plasticity, 2004
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Shi, M., Huang, Y., Gao, H.
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Estimations of bulk geometrically necessary dislocation density using high resolution EBSD

Ultramicroscopy, 2013
Characterizing the content of geometrically necessary dislocations (GNDs) in crystalline materials is crucial to understanding plasticity. Electron backscatter diffraction (EBSD) effectively recovers local crystal orientation, which is used to estimate the lattice distortion, components of the Nye dislocation density tensor (α), and subsequently the ...
T J, Ruggles, D T, Fullwood
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Geometrically necessary dislocations and strain gradient plasticity––a dislocation dynamics point of view

Scripta Materialia, 2003
Abstract The relations between mesoscopic plastic strain gradients, ‘geometrically necessary’ dislocations (GND), and dislocation dynamics are discussed. It is argued that the connection between GND and size effects in crystal plasticity should be established on the basis of dislocation dynamics, taking into account the specific deformation ...
Michael Zaiser, Elias C Aifantis
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Resolving crystallographic geometrically necessary dislocations in three dimensions in a hexagonal close packed titanium alloy

Modelling and Simulation in Materials Science and Engineering
Geometrically necessary dislocation (GND) content is measured from mm3-scaled Ti7Al three-dimensional (3D) microstructural data using a theory extended for hexagonal close packed crystals, which accounts for basal, prismatic and pyramidal ⟨c+a⟩ type ...
Wyatt A. Witzen, James D. Lamb, Mariyappan Arul Kumar, M. Echlin, T.M. Pollock, I. Beyerlein   +5 more
semanticscholar   +1 more source

Crystallographic aspects of geometrically-necessary and statistically-stored dislocation density

Acta Materialia, 1999
Abstract Classical plasticity has reached its limit in describing crystalline material behavior at the micron level and below. Its inability to predict size-dependent effects at this length scale has motivated the use of higher-order gradients to model material behavior at the micron level.
A Arsenlis, D.M Parks
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On the characterization of geometrically necessary dislocations in finite plasticity

Journal of the Mechanics and Physics of Solids, 2001
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
CERMELLI, Paolo, GURTIN M. E.
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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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Assessment of geometrically necessary dislocation levels derived by 3D EBSD

Acta Materialia, 2015
Abstract Existing alternatives for the calculation of geometrically necessary dislocation (GND) densities from orientation fields are discussed. Importantly, we highlight the role of reference frames and consider different sources of error. A well-controlled micro cantilever bending experiment on a copper bicrystal has been analyzed by 3-dimensional ...
P.J. Konijnenberg, S. Zaefferer, D. Raabe   +2 more
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