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Showing 1 to 20 of 27 for “"Dynamic recrystallization"”.
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Mechanisms Operating During Continuous Dynamic Recrystallization in an Aluminum-4magnesium-0.3scandium Alloy
… during continuous static and continuous dynamic recrystallization. The static process was observed to occur much more rapidly than the dynamic process. The dominant mechanism of continuous static recrystallization appears to be the rapid generation of dislocations at sources in grain …
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Modeling and Simulation of Viscoplasticity, Recrystallization, and Softening of Alloyed Steel During Hot Rolling Process
… of this study is to investigate viscoplasticity, dynamic recrystallization, and static softening of alloyed metal during hot rolling process. Gleeble hot compression tests were performed to provide experimental stress-strain curves at different temperatures and strain rates. An inverse finite …
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Nanostructured Copper-Silver Alloys Synthesized by High Energy Ball Milling
… increase, as a result of phase separation and dynamic recrystallization.
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Thermal Structure of Mid-Crustal Shear Zones
… 500-650 "C, corresponding to the temperatures of dynamic recrystallization for subgrain rotation (SGR) and grain boundary migration (GBM). Up to 1000m above the MCT, Td and Tm are within error of each other, suggesting that shearing occurred during peak Tm; while further away from the MCT Tm is …
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Effect of hot working characteristics on the texture development in AISI 430 and 433 ferritic stainless steel
… 20 s and 30 s). The transition temperature from dynamic recrystallization (which may introduce a texture change) to dynamic recovery (in which no texture changes are expected) was determined by examining the relationship between the mean flow stress and the deformation temperature in multi-pass …
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Hot workability of magnesium alloys
… along the old boundaries (mantle) as a result of dynamic recrystallization DRX but not in the core of the initial grains. As T rises, the new grains are larger and the mantle broader, enhanced DRX results in higher ductility. At intermediate T, shear bands form through alignment of mantle zones …
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High temperature aging study on long-term aged Alloy 617 and Alloy 230
… contributor to dislocation pile-up enhancement, dynamic recrystallization (DRX) area fraction increase and fracture mechanisms change, which in turn influence mechanical properties.
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Friction stir welding of high temperature alloys
… in refined grain structure in ODS alloys by dynamic recrystallization mechanism. A critical finding was 'strain induced dispersoid agglomeration'. For Ti-6Al-4V alloy, transformed ß microstructure formed composed of fine acicular α phase (~500 nm in thickness). The fine grain structure …
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Stress-induced Damage and Post-fire Response of Aluminum Alloys
… damage primarily manifests itself as dynamic recovery at low creep temperatures, while cavitation, dynamic recrystallization and dynamic precipitation (in Al6061) are the types of damage developed in the high creep strains at high exposure temperatures. Different creep mechanisms are …
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Additive Friction Stir Deposition of Aerospace Al-Zn-Mg-Cu-Zr Alloys: Leveraging Processing and Metallurgical Science for Structural Repair
… induces sensitivity. This work shows that the dynamic recrystallization necessary to deposit material is detrimental to the fundamental performance of the alloy, making it challenging for thick AA7050 to achieve peak strength. A separate study is shown in which AFSD was utilized to successfully …
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Crystal-plastic deformation and chemical evolution of clinoamphibole
… exhibits microstructures characteristic of dynamic recrystallization, including larger host grains in a finer grained matrix of needle shaped amphibole. The matrix amphibole defines an LS fabric and host grains have core and mantle structures with a core containing undulose to patchy …
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Microstructural, geochronologic and thermochronologic evidence for both Paleo- and Mesoproterozoic displacement across the Gneiss Canyon shear zone : lower Granite Gorge, Grand Canyon, Arizona
… D3 microstructures indicate lower temperature dynamic recrystallization of quartz, as well as brittle deformation suggesting temperatures of <300-450 oC. These D3 domains within GCSZ also indicate west-side-up and/or dextral displacement, and could record retrograde shearing near the end of the …
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From Functionally Graded to Grain-Boundary-Decorated Nanograined Alloys: a New Approach to Bulk Lightweight Alloy Design via Friction Stir Processing
… and functional properties. Current thermodynamic grain boundary (GB) decoration approach for refined-grain stabilization is either limited to thin films or requires multi-step processes. Therefore, new processing routes are needed to produce stable refined-grain materials without these …
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Hot forging of the nickel-base superalloy ATI 718Plus
… To analyse the materials behaviour during meta-dynamic recrystallization, a second set of samples was kept in the furnace for 120s after the compression at high temperature before they were water-quenched. The microstructural changes were investigated using both scanning electron microscope …
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Microstructural and crystallographic fabric analysis of stretched-pebble conglomerates in central Vermont
… that develops within deformed conglomerate. Recrystallization textures within quartz-rich pebbles suggest dynamic recrystallization via subgrain rotation and grain boundary migration. Dynamically recrystallized quartz grains have a grain shape preferred orientation, which is parallel to a …
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Constraining Metamorphic and Tectonic Evolution in Convergent Terranes: How Trace Elements and Mineral Inclusions Shape Mechanical and Reconstructive Models
… due to the low-Ti resetting that occurs with dynamic recrystallization. We applied defect energy simulations and took a global assessment of deformed quartz trace element chemistries to infer that sweeping grain boundaries provide short pathways that allows localized re-equilibration with a …
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Microstructure and texture development during high-strain torsion of NiAl
… temperature T. For T up to 1000K, continuous dynamic recrystallization (CDRX) takes place. This mechanism leads to the deformation-induced dislocations forming low angle grain boundaries (LAGBs) or being incorporated into them and the successive transformation of these boundaries into high …
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Shearing on the Great Glen Fault: Kinematic and Microstructural Evidence Preserved at Different Crustal Levels
The NE-SW trending Great Glen Fault (GGF) is one of mainland Scotland's most significant crustal-scale faults, although our understanding of its early kinematics is in question. Previous studies generally agree that the GGF was initiated as a Silurian sinistral strike-slip fault displacing c. 425 …
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Microstructural evolution during hot deformation of the 6061 aluminium alloy based Al₂O₃ metal matrix composites
… 6061 and the composites was very similar while recrystallization behavor differed markedly. Only up to 5% fraction recrystallized was observed in the 6061 material deformed at temperatures above 723 K and annealed at the deformation temperature, while grain growth was more apparent. Deformation …
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Trace Element Cycling during Iron(II)-activated Recrystallization of Iron(III) Oxide Minerals
… and Fe(III) oxide minerals, which results in dynamic recrystallization via simultaneous Fe(II) oxidative adsorption and Fe(III) reductive dissolution. Fe(III) oxide minerals are abundant in soils, sediments, and groundwater systems, and often control the fate and transport of trace elements. A …
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