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Showing 1 to 20 of 33 for “"Dislocation loops"”.
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Irradiation damage in neutron-irradiated Fe-Cr model alloys
… caused by irradiation damage, including dislocation loops and voids. APT was used to study the precipitation of Cr-rich α' phase under irradiation-enhanced diffusion process. EBSD is used to examine the grain size distribution and possible grain growth. The corresponding mechanical …
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Microstructural investigations of ion (Kr) irradiated UO2
… increases, defects nucleate and grow into dislocation loops and extended networks with increasing dose. At 600°C some dislocation loops form at high dose, but most of the defects remain small and isolated. The in situ 800°C experiment shows the most dislocation loop nucleation and growth. …
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Deuterium Retention and Trapping in Polycrystalline Tungsten under Simultaneous Implantation of Deuterium with Helium and with Neon
… in high energy traps (vacancy clusters or dislocation loops) than in PCW. Post-implantation damage caused by NRA and ERDA probe ion beams resulted in an additional high temperature TDS peak, associated with retrapping of D at ~1.8-2.1 eV vacancy clusters and dislocation loops. Modelling …
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Plastic Instability Due to Collective Dislocation Effect in Portevin-Le Châtelier Effect and Dislocation Nucleation
… (PLC) effect and the cooperative nucleation of dislocation loops, have been studied. In the experimental part of the work, two creep-type mechanical tests have been conducted on a Cu-10at.%Al single crystal and a Mg single crystal to study the plastic instability in the PLC effect and …
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Modeling of Effect of Alloying Elements on Radiation Damage in Metallic Alloys
… Fe-based alloys, including defect production and dislocation loop transformations, and their connections with defect thermodynamics. First, effects of alloying elements on the primary damage in three Fe-based ferritic alloy systems were studied, with a particular focus on the production behaviors …
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Radiation damage in copper indium diselenide
… amorphisation have beenexplored. In particular, dislocation loops have been characterised and theinfluence of composition and temperature on amorphisation has been investigated.In situ and ex situ transmission electron microscopy (TEM) have been used toexamine the effects on CIS of irradiation …
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Advanced characterization of the early-stage evolution of microstructures and mechanical properties in neutron-irradiated commercial steels
… (EDS), the nucleation, growth and stability of dislocation loops, G phase, α’ phase, and other precipitates were quantitatively analyzed. The irradiation hardening in these two materials were characterized using nanoindentation technique. The hardening behaviors were carefully analyzed against …
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Fission gas transport and its interactions with irradiation-induced defects in lanthanum doped ceria
… the formation of complex microstructures with dislocation loops, voids or bubbles, and dislocation networks at higher doses. The Burgers vectors of the dislocation loops were determined and the loops were found to be mainly [111] type Burgers vector pure edge loops. They have been tentatively …
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Fission Gas Transport and Its Interaction With Irradiation Induced Defects in Lanthanum Doped Ceria
… results include size and size distributions of dislocation loops, voids and gas bubble structures created by irradiation. More importantly, this systematic experimental work has provided key insights into the understanding of the mechanisms of defect evolution in the materials investigated. A …
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Heavy-ion damage in copper, nickel and dilute nickel alloys
… resulted in the formation of vacancy dislocation loops which were examined in a transmission electron microscope (TEM) and characterized by their size, Burgers vector, and formation probability. For some of the irradiations, the HVEM-Accelerator Facility and Argonne National Laboratory …
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Development and characterization of nanostructured steels and high entropy alloys for nuclear applications
… diffusion which prevents large voids and dislocation loops from forming in addition to their good phase stability. Most HEA compositions, however, contain Co which activates under irradiation and can cause concerns over waste management. This work studies two compositions of Co-free HEAs …
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Deformation at Low Temperatures in Single Crystal Ni-base Superalloys
… were observed, including planar faults, dislocation loops and dipoles. These defects were common to all alloys studied, but changed in an alloy-specific manner as a function of temperature. Large numbers of fine-scale dislocation loops were observed from 350 °C to 650 °C, with greater …
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Radiation damage in nickel(3) aluminum
… damage structure (namely, disordered zones and dislocation loops) were examined as a function of ion mass (Ar$\sp+$, Kr$\sp+$, Xe$\sp+$), ion energy (30 and 50 keV), and irradiation temperature (30, 300, 350 and 400K). At room temperature and at constant ion energy, the average size of the …
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Low Energy Ion Bombardment Effects in Supersaturated Copper-Indium Alloys
… regions containing residual damage such as dislocation loops. The measured widths of the compositionally altered layers were on the order of the ion penetration range.
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Plasma induced damage to Si and SiGe devices and materials
… centers. The TEM analysis revealed the dislocation loops in Si/Si_{1-x}Ge_x/Si outside the aluminum contact region due to the ion bombardment stress. The O_2 plasma ashing has moderate effect to Si_{1-x}Ge_x device when the device was protected by aluminum contact layer. The C-V …
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Relationship between flow stress recovery and dislocation structure in polycrystalline alpha-titanium
… 6 hours and (2) a leveling off after 6 hours. Dislocation structure was studied by using transmission electron microscopy. During the first stage of recovery, significant rearrangement of dislocations took place. At this stage fairly regular dislocation loops appeared to surround the subgrains. …
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Radiation-induced microstructural and mechanical property modifications in advanced alloys
… the microstructure can be modified in many ways: dislocation loops are formed due to the aggregation of self-interstitial atoms (SIA), the accumulation of vacancies leads to the nucleation of voids, preferential coupling between alloying elements and the defect fluxes results in the elemental …
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Quantifying radiation damage through stored energy released during defect annealing in metals
… and show that the point defect induced glide of dislocation loops contributes significantly to recovery. Our characterisation techniques are combined to propose a new mechanism for the recovery of irradiation-induced defects at elevated temperatures. In order to probe even smaller quantities of …
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Sintering behavior of Ag-Sn alloys prepared via cryogenic high-energy ball milling
… to the presence of stacking faults and dislocation loops. These alloys prove to sinter better and achieve higher densification than pure Ag. The 15at%Sn alloy achieves a density of 65% when compacted at 350◦C for 1hr under 7 MPa applied load, compared to 54% for pure Ag under similar …
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Phonon scattering from substitutional impurities and lattice defects in silver chloride
… that the phonon scattering is mainly due to dislocations and that diffusive boundary scattering is perhaps due to the dynamical dislocation loops beneath the surface. The pure single crystal thermal conductivity curve was fitted by using the Debye thermal conductivity integral. Due to the …
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