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Showing 1 to 13 of 13 for “"Radiation enhanced diffusion"”.
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Radiation-Enhanced Diffusion of Lanthanum in Cerium Dioxide Thin Films
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A systematic study of radiation enhanced diffusion; theoretical improvement and application
A new rate theory model for the radiation enhanced diffusion (RED) has been developed. To improve the traditional mean-field theory, which assumes all defects are produced uniformly and continuously in the form of Frenkel pairs under irradiation, the new model considers more realistic defect …
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Radiation-enhanced diffusion of oxygen-18 in uranium dioxide thin films
Anion radiation enhanced diffusion (RED) and thermal diffusion of a buried 18O tracer layer in thin film UO2 was measured using Secondary-Ion Mass Spectroscopy (SIMS). Thin films were grown using a dedicated magnetron sputtering chamber. Samples were irradiated with 1.8 MeV Kr+ over a temperature …
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Radiation enhanced diffusion of neodymium in single crystal thin film UO2
Radiation-enhanced diffusion (RED) of a Nd buried tracer layer in UO2 thin films was measured with Secondary Ion Mass Spectrometry (SIMS). Samples were irradiated with 1.8 MeV Kr+ over a temperature range from 400 to 800 C. RED in UO2 was found to be in the recombination limited regime. Dose rate …
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Radiation-Enhanced Diffusion and Defect Production During Ion Irradiation of MgO and Al(2)O(3)
Radiation enhanced diffusion of O$\sp{18}$, Ca and Zn buried tracer layers in MBE grown MgO was measured following irradiation with either 2.0 MeV Kr or 1.0 MeV Ne, He or H from 30 to 1500$\sp\circ$C. This represents the first reported RED measurements on an oxide system. Ion beam mixing at …
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Atomic transport mechanisms in irradiated copper(3)-gold alloy
The properties of radiation-induced defects were investigated by examining the radiation-enhanced diffusion and radiation-induced order-disorder kinetics in the ordered intermetallic alloy Cu$\sb3$Au.
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Microstructural evolution of zirconium carbide (ZrCₓ) ceramics under irradiation conditions
… Carbide (ZrC<sub>2</sub>) ceramics under irradiation conditions is required for their successful implementation in advanced Gen-IV gas-cooled nuclear reactors. The research presented in this dissertation focusses on elucidating the ion and electron irradiation response of ZrC<sub>2</sub> …
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Materials Design for Advanced Nuclear Energy Systems: Refractory High Entropy Alloys and Metallic Multilayer Composites
… corrosive environments, and neutron radiation damage. In this thesis, I focus on two approaches to designing better materials for advanced reactors, high entropy alloys (HEAs) and metallic multilayer composites (MMLCs). HEAs are chemically disordered solid solutions combining 4-5 or …
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Irradiation-induced nanoclusters and their evolution in compound forming ni-base and cu-base alloys
… studied for designing materials tolerant to irradiation at high temperatures. The challenge is that nanostructures will often coarsen under elevated temperature irradiation or annealing, owing in part to radiation-enhanced diffusion. In this thesis, we propose a scheme to enhance the stability …
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Compositional modifications in alloys under irradiation
… and subsurface compositions of alloys during irradiation has been investigated theoretically using a phenomenological model that includes preferential sputtering, displacement mixing, radiation-enhanced diffusion, radiation-induced segregation and Gibbsian adsorption. Sample calculations were …
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The effect of irradiation temperature on REBCO Jc degradation and implications for fusion magnets
… do not exist to perform cryogenic neutron irradiations at the present. In addition, reactor studies are costly and activate the samples, requiring long cooldown times and specialized analysis facilities to handle radioactive material. In order to complement reactor irradiation studies of HTS …
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Impact of cellular dislocation structures produced by additive manufacturing on neutron irradiation damage evolution in stainless steel 316L
… features and their potential impact on irradiation-induced damage mechanisms must be studied. Stainless steel 316L (SS-316L) samples were irradiated in the Advanced Test Reactor overa range of fast neutron fluences as part of a grant received by the Colorado School of Mines. …
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Radiation-induced microstructural and mechanical property modifications in advanced alloys
… and sustainable clean energy sources with enhanced energy efficiency and safety features. These improved attributes necessitate advanced structural materials that can withstand harsh reactor environments such as high pressure, high temperature, corrosion, and most importantly, high dose …