Showing papers on "Zirconium alloy published in 2014"
TL;DR: In this article, three general strategies for accident tolerant fuels are explored: modification of current state-of-the-art zirconium alloy cladding to further improve oxidation resistance (including use of coatings), replacement of Zr Alloy cladding with an alternative oxidation resistant high-performance cladding, and replacement of the monolithic ceramic oxide fuel with alternative fuel forms.
695 citations
TL;DR: In this article, an application of advanced oxidation-resistant iron alloys as light water reactor fuel cladding is proposed, based on specific limitations associated with zirconium alloys.
397 citations
TL;DR: In this article, a detailed characterization of nanostructured thin zirconium oxide films formed during aqueous corrosion of a nuclear-grade ZrConium alloy (Zircaloy-4) has been carried out by means of two novel, ultra-high-spatial-resolution grain mapping techniques, namely automated crystal orientation mapping in the transmission electron microscope (TEM) and transmission electron backscatter diffraction (t-EBSD).
116 citations
TL;DR: In this paper, the effects of alloying elements, microstructure and corrosion kinetics on hydrogen uptake were investigated in zirconium-based alloys used for nuclear fuel cladding.
114 citations
TL;DR: In this paper, the authors addressed the feasibility issues facing the application of SiC-matrix microenculated fuels for light water reactor application and found that the SiC matrix was quite stable with behavior similar to that of CVD SiC.
84 citations
TL;DR: In this paper, thin films of TiN and Ti0.35Al 0.65N nanocomposite were deposited on polished Zircaloy-4 tubes, and after exposure to supercritical water for 48 h, the coated tubes are remarkably intact, while the bare uncoated tube shows severe oxidation and breakaway corrosion.
71 citations
TL;DR: In this paper, a 3D fuel performance code BISON is implemented in order to calculate the hydrogen distribution for arbitrary geometries, such as a nuclear fuel rod, and is now available for BISON users.
57 citations
TL;DR: In this article, the authors investigated the link between the tetragonal to monoclinic oxide phase transformation and degradation of the protective character of the oxide layer, and used the maximum principal stress as an indication of fracture in the surrounding oxide layer.
55 citations
TL;DR: An atom probe tomography study of the microstructure of a Zircaloy-2 material subjected to 9 annual cycles of BWR exposure has been conducted in this paper, where Fe and Cr are seen to reprecipitate in large numbers of clusters and particles of 1-5 nm sizes throughout the Zr metal matrix Fe and Sn were observed to segregate to ring-shaped features in the metal that are interpreted to be -component vacancy loops.
55 citations
TL;DR: In this paper, Zr-12Mo-xTi alloys with required properties have been designed and prepared using vacuum arc melting method for the first time, and phase analysis and microstructural observation shows that all the as-cast samples consist of equiaxed β-Zr phase.
44 citations
TL;DR: In this paper, compositional changes in second phase particles in Low Tin ZIRLO™ after neutron and proton irradiation using energy dispersive X-ray (EDX) spectroscopy were investigated.
TL;DR: In this paper, the authors investigated the chemical state evolution of two alloying elements, Fe and Nb, when incorporated into the growing oxide layers of various production zirconium alloys, including Zircaloy-4, ZIRLO® and Zr 2.5Nb.
TL;DR: In this article, the behavior of water droplets near the Leidenfrost point (LFP) on zirconium alloy surfaces with anodizing treatment and investigated the droplet cooling performance.
TL;DR: In this article, a special emphasis was placed upon the role of zirconium suboxides in hydrogen uptake reduction and the atomic mechanisms of oxidation, and computational thermodynamics calculations were conducted concurrently with first-principles atomistic modeling.
TL;DR: In this paper, a nodal dislocation dynamics code adapted to Hexagonal Close Packed metals has been used to investigate the interaction mechanisms between gliding dislocations and loops in zirconium.
TL;DR: In this article, the phase transformation behavior of U-Zr alloys was observed using differential scanning calorimetry (DSC) with thermogravimetric analysis (TGA).
01 Jan 2014
TL;DR: In this paper, various zirconium alloys are discussed in terms of their physical and mechanical properties, microstructure, chemical properties, and corrosion properties, the effect of manufacturing processes like fabrication, handling, welding, heat treatment, and chemical cleaning etc., on the corrosion behavior of the ZIRCONIUM alloys is discussed.
Abstract: Zirconium alloys are used in nuclear application due to good corrosion resistance, resistance to irradiation damage, adequate mechanical properties and transparency to thermal neutrons. Chemical process industry application arises from excellent resistance to a broad range of corrosives. In this paper, various zirconium alloys are discussed in terms of their physical and mechanical properties, microstructure, chemical properties, and corrosion properties. The effect of manufacturing processes like fabrication, handling, welding, heat treatment, and chemical cleaning etc., on the corrosion behavior of the zirconium alloys is discussed. Different kinds of corrosion of zirconium alloys in various environments are reported.
TL;DR: In this paper, the formation of hydride blisters in zirconium alloys was studied from an experimental and theoretical standpoint, and their characterization in terms of morphology, hydrides crystallographic phases, hardness and hydrogen concentration.
TL;DR: In this paper, the behavior of the precipitate in a Zr-1.6Sn−0.1Cr alloy under a 2-MeV proton irradiation was studied by transmission electron microscopy (TEM).
TL;DR: In this article, a detailed microstructure and texture study of various hydrided Zircaloy-4 materials by neutron diffraction and microscopy is presented, and it is shown that the precipitated δ-ZrH1.66 generally follows the δ(111)//α(0001) and δ[1{\overline 1}0]//α[11{overline 2} 0] orientation relationship with the α −Zr matrix, which contributes to the accommodation of the substantial misfit strains associated with hydride precipitation in
Abstract: This work presents a detailed microstructure and texture study of various hydrided Zircaloy-4 materials by neutron diffraction and microscopy. The results show that the precipitated δ-ZrH1.66 generally follows the δ(111)//α(0001) and δ[1{\overline 1}0]//α[11{\overline 2}0] orientation relationship with the α-Zr matrix. The δ-hydride displays a weak texture that is determined by the texture of the α-Zr matrix, and this dependence essentially originates from the observed orientation correlation between α-Zr and δ-hydride. Neutron diffraction line profile analysis and high-resolution transmission electron microscopy observations reveal a significant number of dislocations present in the δ-hydride, with an estimated average density one order of magnitude higher than that in the α-Zr matrix, which contributes to the accommodation of the substantial misfit strains associated with hydride precipitation in the α-Zr matrix. The present observations provide an insight into the behaviour of δ-hydride precipitation in zirconium alloys and may help with understanding the induced embrittling effect of hydrides.
TL;DR: In this paper, a polycrystalline diamond layer was used for protection of zirconium alloy nuclear fuel cladding against undesirable oxidation with no loss of chemical stability and preservation of its functionality.
TL;DR: In this paper, the formation mechanism of the hydride network with a high degree of continuity and its influence on the ductile-to-brittle transition of zirconium alloys are investigated.
TL;DR: In this article, the ternary Al-Sc-Zr diagram, solidification conditions, features of aluminum solid solution of scandium and zirconium, and recrystallization are considered.
Abstract: Scandium is introduced into commercial aluminum alloys together with zirconium, which stabilizes and strengthens the favorable effect of scandium. The nature of this phenomenon, including analysis of the ternary Al – Sc – Zr diagram, solidification conditions, features of aluminum solid solution of scandium and zirconium, and recrystallization, are considered in this article.
TL;DR: In this article, a thermal-mechanical test was proposed to determine the minimum hoop stress required to precipitate radial hydride and a maximum stress above which, all hydrides precipitate in the radial direction.
TL;DR: In this article, the authors developed a mathematical model and carried out numerical simulation of one-dimensional heat conduction with phase change in a nuclear fuel rod including two regions: uranium dioxide fuel pellet and zirconium alloy cladding.
TL;DR: This study evaluates the solid-phase speciation of zirconium and fluoride in Hanford Site waste using X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS).
TL;DR: In this paper, the effect of hydrogen on the creep behavior of Zirconium alloys used in the water reactors is discussed and a detailed review of the effects of hydrogen in Zr alloys is presented.
Abstract: Zirconium (Zr) alloys are the primary structural materials of most water reactors. Creep is considered to be one of the important degradation mechanisms of Zr alloys during reactor operating and repository conditions. Zr alloys pick up hydrogen (H2) during their service from the coolant water. Hydrogen can be present in solid solution or precipitated hydride form in Zr alloys depending upon the temperature and concentration. This study reviews the effect of hydrogen on creep behavior of Zr alloys used in the water reactors.
TL;DR: In this paper, a trade-off between doping concentration and photovoltaic properties was investigated by using X-ray diffraction measurements, which showed that homovalent substitution of Zr in TiO2 increased the chemical capacitance and electron diffusion coefficient which in turn decreased charge transport resistance and charge transit time.
Abstract: Zirconium (Zr) is doped up to 5 at. % in anatase TiO2 nanowires by electrospinning and used as working electrode in dye-sensitized solar cells. Variations observed in the photovoltaic parameters were correlated by electrochemical impedance spectroscopy, open circuit voltage decay, and X-ray diffraction measurements. Results show that homovalent substitution of Zr in TiO2 increased the chemical capacitance and electron diffusion coefficient which in turn decreased charge transport resistance and charge transit time. However, lattice strain due to size mismatch between the Zr4+ and Ti4+ ions decreased open circuit voltage and fill factor thereby setting a trade-off between doping concentration and photovoltaic properties.
TL;DR: In this paper, the parabolic rate constant for Zircaloy-4 tubing samples at 1200°C was determined to be k ǫ = 2.173 −1.173 × 10 7 −1/cm 4 /s, in excellent agreement with the Cathcart-Pawel correlation.