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Showing 1 to 20 of 47 for “"Misorientation"”.
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The variation of subgrain misorientation in aluminum with large steady-state creep strain
… = 0.20) all subgrain boundaries had small misorientations, typically, 0.6. The misorientation across boundaries formed as a result of dislocation accumulation continued to increase well past steady-state up to a strain of about 1.2, where a maximum average value of 1.2 was observed. This …
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Healing of defects in a two-dimensional granular crystal
… times in order to collect data on a range of misorientations. In some cases, the misorientation angle varied significantly during healing so both initial misorientation and time averaged misorientation angle were considered as possible driving variables for healing rate. Healing times were fit …
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Topological analysis of the grain boundary space
… characterization, including the boundary misorientation and inclination parameters, of grain boundaries. Despite these advances, a lack of appropriate analytical tools severely undermines our ability to analyze and exploit the full potential of the vast amounts of experimental data …
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Normal state properties of high-angle grain boundaries in Y$_{1-x}$Ca$_{x}$Ba$_{2}$Cu$_{3}$O$_{7-}$$_\delta$
… A grain boundary is characterised by the misorientation angle between the two adjacent crystals, which determines the atomic structure of the interface. The structure of low-angle grain boundaries (misorientation angles < ~7°) is well understood; it consists of a regular array of …
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Computer generation of Kikuchi projections and characterization of general bicrystals
Three parameters, i.e., misorientation angle, misorientation axis, and boundary normal, have been used to describe a general bicrystal, such as two adjacent grains, subgrains, twins, or two neighboring phases. A computer program has been developed to determine these three parameters. The angle and …
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Evolução das tensões residuais e sua relação com a “misorientação” microestrutural de um aço astm dh36 após soldagem
… RAYSTRESS. A study of the grain boundaries misorientation has been carried out with the purpose of explaining this phenomenon by the microstructure alteration. For the analysis of the microstructure, thermomechanical simulation with Gleeble®3800 equipment and scanning electronic microscopy …
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Molecular Dynamics Studies of Anisotropy in Grain Boundary Energy and Mobility in UO₂
… The dependence of these properties on both misorientation angle and rotation axis is studied. The anisotropy in grain boundary energy is found to be insignificant in UO₂. However, grain boundary mobility shows significant anisotropy. For both 20º and 45º misorientation angles, the anisotropy …
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Insights into magmatic processes from the crystal orientation mapping of igneous microstructures
… typically form euhedral shapes without internal misorientation. However, crystals that grow at high supersaturation commonly display complex morphologies with high internal misorientation. I use EBSD to characterise these crystals in order to explore the poorly understood topic of disequilibrium …
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Embrittlement and Flow Localization of Reactor Structural Materials
… utilizing finite element method (FEM) and EBSD misorientation map for unirradiated and irradiated 316L stainless steel. The major issue of interest is the possibility that low ductility, often found following irradiation exposure, will translate into low notch toughness. The influence of …
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Grain-Boundary Parameters Controlled Allotriomorphic Phase Transformations in Beta-Processed Titanium Alloys
… to the grain-boundary parameters namely, misorientation angle and axis, and the GB plane. While the misorientation angle and axis relate to the crystallography of adjacent crystals and can easily be determined using diffraction based techniques, an accurate determination of the local …
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Hot workability of magnesium alloys
… and prismatic slip, Forming cells of augmented misorientation first near the grain boundaries and later towards the grain cores. Near the peak, new grains appear along the old boundaries (mantle) as a result of dynamic recrystallization DRX but not in the core of the initial grains. As T rises, …
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Grain boundaries in coated conductors
… showed the expected decrease with increasing misorientation angle at low fields. At higher fields an angle dependent crossover was found, from a GB to grain limited Jc. In order to confirm this result and put it into broader perspective, the dependence of Jc on the width of polycrystalline …
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Mechanisms Operating During Continuous Dynamic Recrystallization in an Aluminum-4magnesium-0.3scandium Alloy
… rotation resulting in increased boundary misorientation was not observed; however, the restraints imposed by the thin foil geometry of the tensile TEM samples may be the reason for this.
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Characterization of structural changes in thermally enhanced Kevlar-29® Fiber
… that hydrogen bond disruption and concurrent misorientation of crystallites may account for the observed augmentation of compressive properties. To examine the said theory, virgin Kevlar-29® fibers were characterized by Thermogravimetric analysis (TGA) and Differential Scanning Calorimetry …
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Uncovering the link between twin-twin interactions and damage nucleation in an (α+β) Ti alloy
… along {10̅12} twin-twin boundaries with a ~60° misorientation. The {10̅12} twinning mode is only activated in the localized neck, and twin activation is strongly dependent on initial crystallographic texture. The twinned domains are rotated such that prismatic slip is easier to activate, but …
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Microstructural analysis of aluminium alloy 2096 as a function of heat treatment.
… precipitation near to and on low and high angle misorientation grain boundaries. The low-angle grain boundaries of the UA4 temper exhibited a fine, near continuous decoration of T1 precipitates and a narrow, but distinct T1 precipitate free zone (PFZ) adjacent to the boundary. The high angle …
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Study of nonlinear microwave properties of high-temperature superconducting film
… of engineeried bicrystal grain boundaries with misorientation angles of [theta] = 2⁰, 5⁰, 7.5⁰, 10⁰, and 24⁰ were measured using a suspended microstrip resonator with temperature ranging from 5 to 75 K.
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Gefügeeinfluß auf das Elektromigrationsverhalten von Kupferleitbahnen für höchstintegrierte Schaltungen
… The frequency densities of the grain boundary misorientation, which is important for the electromigration behavior, are very different for both films. The ECD lines show a fraction of 55% Sigma 3 twin boundaries and 40% high angle grain boundaries. In contrast the PVD interconnects show a …
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Roles of grain boundaries in cleavage cracking and thermal crack arrest experiments in iron-silicon alloy
… grain boundaries, with a given tilt and twist misorientation across them, and detailed measurements of orientations of individual grains in the samples, it was possible to develop percolation maps of cleavage through the field of grains that for the initial phases of fracture through grains …
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Dynamics of sliding mechanisms in nanoscale friction
… have the lowest friction due to the intrinsic misorientation at the sliding interface. In the amorphous system, sliding occurs by a series of random local slips due to the individual atomic motion associated with the disordered structure.
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