Global ETD Search
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Showing 1 to 8 of 8 for “"Geometrically Necessary Dislocations"”.
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Quantifying Dislocation Microstructures
… information, we were then able to infer how the dislocations propagated from the notch into the specimen. We propose using the so-called 'discrete-to-continuous' (D2C) method, which converts discrete dislocation data to continuum fields, as a means to quantify microstructures. With this method, …
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Kinetics of Plastic Flow in Polycrystal Plasticity
… and includes a hardening contribution from geometrically necessary dislocations (net/excess dislocations). To perform the computations a novel lattice rotation integration algorithm, based on an analytical solution, has been developed. Implicit and explicit formulations are presented, and …
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Heterogeneous Redox Chemistries in Layered Oxide Materials for Lithium-Ion Batteries
… breakdown. Crystallographic defects, such as dislocations and grain boundaries, are rich in battery materials. These crystallographic defects change the local lithium-ion diffusivity and have a dramatic effect on the redox reactions. To date, there is still a knowledge gap on how various …
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Strain gradient plasticity-based modeling of damage and fracture
… small scales. Grounded on the physical notion of geometrically necessary dislocations (GNDs, associated with non-uniform plastic deformation), SGP theories relate the plastic work to both strains and strain gradients, introducing a length scale in the constitutive equations. While growing interest …
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Scale effects in microindentation of ductile crystals
… with conical or pyramidal indenter tips is geometrically similar, the existence of a size effect was surprising. Since the size effect associated with microindentation was discovered, many theories about its cause have been proposed. Several of the theories suggest that the source of the …
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Dry sliding wear of metals: From subsurface microstructure to tribological behavior
… The lattice curvature was studied in terms of geometrically necessary dislocations calculated from the orientation difference between neighboring points in space. Periodic microstructural instability was systematically observed at the leading edge of twin boundaries in CuNiSn pins after …
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Exploration of incompatibility in Al-Li alloys using high energy diffraction microscopy and a crystal plasticity model
Aluminum-lithium (Al-Li) alloys have inherently desirable properties such as increased specific stiffness and strength. Without question, these alloys would be candidate materials for many aerospace structural designs if it were not for a complicated and confounding mode of fracture termed …
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Microstructure property development in friction stir welds of aluminim based alloys
… welds, especially the interaction between the dislocations and the fine Al6(Fe,Mn) dispersoids, indicated that establishing a structure-property model requires the incorporation of the various strengthening factors. Stereological studies of the grain size and intermetallic particle …