... whether this difference in entropy has an impact on the overall Gibbs free energy and stabilization of amorphous chromium-doped ZrO 2 systems. thermodynamics amorphous grain boundaries oxides stability doping alloying elements ZIRCONIUM IN THE NUCLEAR INDUSTRY: 20TH INTERNATIONAL SYMPOSIUM...

... interaction with various microstructural features. Toward that end, we have employed molecular statics, molecular dynamics, and the dimer method of potential surface mapping to study the fate of helium in the vicinity of dislocations and grain boundaries in alpha-iron. Even at very low temperatures...

... be intergranular embrittlement caused by grain boundary phosphorus segregation. A threshold dose was used that accounts for intergranular embrittlement, that occurs after sufficient phosphorus segregation, when the critical stress for intergranular fracture falls below that for cleavage fracture. The modeling...

... (sample surfaces, grain boundaries) point defect sinks has been carried out in order to compare the kinetics and extent of segregation at various point defect sinks. Dilute Fe-P alloys relevant to model and VVER-440 pressure vessel steels were considered. It is shown that the time to reach steady state...

... This paper presents a systematic review of the behavior of phosphorus (P), highlighting the implications of P segregation to grain boundaries under neutron irradiation. The review focuses on Mn-Mo-Ni steels employed in US pressurized water reactors (PWRs), and other PWRs worldwide. Segregation...

... Kinetics of phosphorus accumulation on grain boundaries (GB) in iron-based alloys is treated theoretically, taking into account both the radiation-induced segregation (RIS) in the matrix and the Gibbsian adsorption (GA) at GB. For steady-state conditions analytical expressions are derived...

... and predicted phosphorus intergranular segregation in a range of pressure vessel steels is also discussed. grain boundaries segregation neutron irradiation steels ductile-to-brittle transition analytical electron microscopy Shenhua Song,1Roy G. Faulknerl, and Peter E. J. Flewitt2 Grain Boundary...

... Analytical investigations employing field-emission gun scanning transmission electron microscopy (FEGSTEM) have indicated that the degree of chromium depletion at grain boundaries is less pronounced in AISI type-316 when compared to type-304 stainless steel after neutron irradiation in Boiling...

... A model of the radiation-induced segregation (RIS) and thermal non- equilibrium segregation (TNES) at grain boundaries has been established within a phenomenological theory. This model indicates that the magnitude and extent of segregation is dependent upon the formation of solute-point defect...

..., and • reductions in creep-fatigue endurance. By considering the influence of irradiation temperature and dose level, the results are rationalised in terms of irradiation hardening and grain boundary embrittlement mechanisms. Pressurised Water Reactor Fast Breeder Reactor internal structures irradiation...

... particularly in terms of helium generation rate and recoil energy. copper Cu-Al 2 O 3 600 MeV protons helium multi-displacement cascades grain boundaries twin boundaries bubbles voids cavities Bachu N. Singh I and Andy Horsewell I EFFECTS OF CASCADE DAMAGE AND HELIUM PRODUCTION UNDER 600 MeV...

... interiors, helium flux to and bubble density at grain boundaries are described and discussed. The bubble nucleation in the grain interiors and the helium flux to grain boundaries can be understood within the framework of the di-atomic type homogeneous nucleation. The nucleation in the grain interiors...

... Intergranular corrosion of irradiated austenitic steels has been attributed to compositional changes produced by radiation-induced segregation at grain boundaries, and the effect has been investigated for the 20Cr/25Ni/Nb stainless steel employed as fuel cladding in advanced gas-cooled reactors...

... not only the influence of the large swelling levels attained during irradiation but also the distribution of swelling near grain boundaries. The unique fracture mode in highly voided copper appears to enhance susceptibility to crack propagation and sudden failure without necking, even though the material...

... on the macroscopic, microstructural, and atomic scales. These are taken from work on long- and short-range diffusion of hydrogen in amorphous alloys, grain-boundary sliding in metallic films, and point-defect reorientation in doped layers of silicon. New experimental approaches using the vibrating-membrane...

...; but the low interstitial alloy (E-Brite) hydrogen embrittled transgranularly only when both of these treatments were given in this order. The cracks originated at the surface grain boundaries in 26-1S and at interior precipitate regions in E-Brite. Based on interrupted tests and fractography, the inferred...

... Experimental results are used to determine the dependence of bubble density, at grain boundaries as well as within the grains, on irradiation temperature and helium gen eration rate. The measured flux of helium to grain boundaries is then related to helium generation rate. Finally...

... up to 15 μm from grain boundaries. The magnitude of the enhanced vacancy accumulation varies as a function of distance from the grain boundary. The presence of subgrain boundaries enhances the vacancy accumulation within the subgrain, and the vacancy accumulation varies markedly as a function...

... of the inverse Kirkendall effect. The vacancy gradients driving the diffusion in these experiments are generated not only by the foil surfaces and the electron-generated radial displacement gradient but also by high angle grain boundaries deliberately centered in the middle of the electron beam. This procedure...

... mechanisms then become important components of the swelling These mechanisms include growth by diffusion, for bubbles within grains and on grain boundaries; dislocation nucleation at the bubble surface, or “punchout”; and bubble growth by creep. Analyses of these mechanisms are presented and applied...