Download or read book Irradiation Effects on Fe Distributions in Zircaloy 2 and Zr 2 5Nb written by Chalk River Nuclear Laboratories. Reactor Materials Research Branch and published by Chalk River, Ont. : Reactor Materials Research Branch, Chalk River Laboratories. This book was released on 1995 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of In PWR Irradiation on Size Structure and Composition of Intermetallic Precipitates of Zr Alloys written by F. Garzarolli and published by . This book was released on 1996 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: The corrosion behavior of Zr alloys depends on the kind, size, and distribution of the intermetallic second-phase particles. TEM examinations of Zr-Sn-Fe-Cr alloys irradiated in PWRs at temperatures between 300 and 370°C and fast fluences in the range of 5E21 to 1.3E22 cm-2 have been performed to study the irradiation-induced effects on the precipitates. The alloys contained different types of second-phase particles such as Zr(Fe,Cr)2, Zr2(Fe,Si), and Zr3Fe before irradiation. The influence of irradiation was found to depend on temperature and type of second-phase particles.

Download or read book Zirconium in the Nuclear Industry written by George P. Sabol and published by ASTM International. This book was released on 1996 with total page 907 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Irradiation of Zircaloy 2 Impact Specimens Containing Hydrogen written by R. G. Wheeler and published by . This book was released on 1955 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Irradiation Induced Growth and Microstructure of Recrystallized Cold Worked and Quenched Zircaloy 2 NSF and E635 Alloys written by D. W. White and published by . This book was released on 2008 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper is devoted to the study of the effect of the texture, phase composition, and microstructure on the irradiation-induced growth strain (GS) of zirconium-based alloys. GS measurements and TEM microstructural examinations were performed on Zry-2, NSF, and E635 samples in the recrystallized, beta quenched and cold-worked (CW) conditions. The samples were irradiated in the BOR-60 reactor in the temperature range of 315-325°C up to a neutron fluence level of 1.1 x 1026 n/m2 (E>1MeV), i.e., up to a damage dose of 23 dpa. Growth strains of NSF and E635 alloys in all states and in the longitudinal and transverse directions are lower as compared to those of Zry-2, and do not exceed 0.2 % even at the maximum fluence level. As for recrystallized Zry-2, the GS kinetics are characterized by the appearance of the accelerated growth stage. A combination of a certain amount of Nb, Fe, and Sn in the matrix content plays a key role in GS kinetics. The higher the degree of CW, the higher the irradiation growth but its rate of increase with increasing fluence is different for alloys of different compositions. The maximum GS, reaching 0.72 %, is observed in the 20 % CW Zry-2 samples. Texture, along with the alloy composition, is one of the main GS-determining factors. Irradiation growth of the transversal samples is lower as compared to the longitudinal ones because of texture. As for quenched alloys, the texture is practically isotropic and GS values are low, independent of the alloy composition. In CW materials, the density of ‹c›- dislocations greatly affects the irradiation growth strain. Particles of Zr(Fe,Cr)2 and Zr2(Fe,Ni) phases in Zry-2 as well as Zr(Nb,Fe)2 in NSF and E635 are depleted in iron under irradiation. The Fe goes into the matrix and modifies its properties. The HCP lattice structure in the Laves phases in NSF and E635 changes into BCC (?-Nb-type). FCC (Zr,Nb)2Fe precipitates preserve on the whole their composition and structure; no amorphization of the Nb-containing precipitates is observed. The Zr2(Fe,Ni) precipitates with a BCT lattice remain crystalline, and HCP Zr(Cr,Fe)2 precipitates undergo amorphization. The average particle size in the irradiated alloys is larger and the concentration is a little lower as compared to the unirradiated ones. Irradiation-induced fine dispersed precipitates about 3 nm in size, probably enriched in niobium, appear in NSF and E635. The observed changes of microhardness are discussed from the viewpoint of generation of radiation defects (clusters, dislocation loops), evolution of the initial dislocation structure, and matrix composition (enrichment in Fe, Cr, and, probably, Nb).

Download or read book The Effect of Iron on Dislocation Evolution in Model and Commercial Zirconium Alloys written by Matthew Topping and published by . This book was released on 2018 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: Although the evolution of irradiation-induced dislocation loops has been well correlated with irradiation-induced growth phenomena, the effect of alloying elements on this evolution remains elusive, especially at low fluences. To develop a more mechanistic understanding of the role iron has on loop formation, we used state-of-the-art techniques to study a proton-irradiated Zr-0.1Fe alloy and proton- and neutron-irradiated Zircaloy-2. The two alloys were irradiated with 2-MeV protons up to 7 dpa at 350°C and Zircaloy-2 up to 14.7 x 1025 n . m-2, approximately 24 dpa, in a boiling water reactor at approximately 300°C. Baseline transmission electron microscopy showed that the Zr3Fe secondary-phase particles in the binary system were larger and fewer in number than the Zr(Fe,Cr)2 and Zr2(Fe,Ni) particles in Zircaloy-2. An analysis of the irradiated binary alloy revealed only limited dissolution of Ze3Fe, suggesting little dispersion of iron into the matrix, while at the same time a higher a-loop density was observed compared with Zircaloy-2 at equivalent proton dose levels. We also found that the redistribution of iron during irradiation led to the formation of iron nanoclusters. A delay in the onset of c-loop nucleation in proton-irradiated Zircaloy-2 compared with the binary alloy was observed. The effect of iron redistributed from secondary-phase particles because of dissolution on the density and morphology of a and c loops is described. The implication this may have on irradiation-induced growth of zirconium fuel cladding is also discussed.

Download or read book The Effects of Anisotropy and Irradiation on the Deformationbehavior of Zircaloy 2 written by Electric Power Research Inst., Palo Alto, CA (USA) and published by . This book was released on 1979 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Irradiation Effects on Zircaloy 2 uranium Bonds written by J. W. Goffard and published by . This book was released on 1960 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Amorphization Kinetics of Zr Cr Fe 2 Under Ion Irradiation written by Arthur T. Motta and published by Chalk River, Ont. : Reactor Materials Research Branch. This book was released on 1994-01-01 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Irradiation induced Phase Transformations in Zirconium Alloys written by and published by . This book was released on 1994 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: 4°Ar and 2°9Bi ion irradiations of Zr3Fe were performed at 35--725 K using 15-1500 keV ions. Results are presented on role of deposited-energy density on nature of the damaged regions in individual cascades produced by ion bombardment of Zr3Fe. Comparison is also made between irradiation-induced amorphization of Zr3Fe during electron irradiation and under ion bombardments. Dependence of damage production on incident electron energy in Zr3Fe was also determined. Preliminary results are also discussed for amorphization of ZrFe2, Zr(Cr, Fe)2 and ZrCr2 by electron irradiation. Results of a recent investigation on amorphization of Zr(Cr, Fe)2 and Zr2(Ni, Fe) precipitates in Zircaloy-4 are discussed in context of previous experimental results of neutron and electron irradiations and likely amorphization mechanisms are proposed.

Download or read book Amorphization Kinetics of Zr Cr Fe 2 Under Ion Irradiation written by and published by . This book was released on 1992 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thin foils of Zircaloy-4 were irradiated with 350 KeV 4°Ar ions in the dual ion beam/HVEM facility at Argonne National Laboratory at 300--650 K. The irradiation-induced amorphization of the intermetallic precipitates Zr (Cr; Fe)2 and Zr2 (Ni, Fe) was studied in-situ. For Zr (Cr, Fe)2 precipitates the dose-to-amorphization was found to increase exponentially with temperature, with a critical temperature of about 650 K. The amorphization morphology was shown to be homogeneous, with no preferential site for nucleation, in contrast to neutron-irradiation amorphization which started at the precipitate-matrix interface. For Zr2 (Ni, Fe) precipitates it was found that amorphization occurred at 550 and 600 K, whereas in neutron irradiation no amorphization has been observed at those temperatures. The results are discussed in context of previous neutron and electron irradiations and likely amorphization mechanisms are proposed.

Download or read book Electron Irradiation Induced Amorphization of Precipitates in Zircaloy 2 written by AJ. Machiels and published by . This book was released on 1990 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: The crystalline-amorphous transformation of Zr2(Ni,Fe) precipitates in Zircaloy by electron irradiation has been studied in the high voltage electron microscope at temperatures ranging from 92 to 283 K and dose rates between 10-3 and 4 x 10-2 dpa/s. The dose-to-amorphization was found to increase exponentially with temperature and to decrease with increasing dose rate. The occurrence of the transformation was modeled by calculating the increase in free energy because of irradiation effects: accumulation of point defects and lattice disordering. The time-dependent diffusion equation with recombination was solved to find the interstitial and vacancy concentrations as functions of dose, dose rate, and temperature. Random recombination was the assumed disordering mechanism. The transformation was assumed to occur when the free energy increase of the crystalline phase became equal to the difference in free energy between the amorphous state and the unirradiated crystal. The dose-to-amor phization predicted by the model agreed well with experimental results for reasonable values of the fitting parameters.

Download or read book Effect of Irradiation at 588 K on Mechanical Properties and Deformation Behavior of Zirconium Alloy Strip written by J. Baicry and published by . This book was released on 1987 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: Irradiation tests conducted for the Advanced Fuel Assembly (AFA) grid development allowed the measurement of the mechanical characteristics, growth, and relaxation of the following materials: stress-relieved, ?-annealed, and ?-quenched Zircaloy-4, and ?-annealed Zr-3Sn-1Mo. The mechanical characteristics of the zirconium alloys approached a limit value as early as 5 x 1024 n m-2, except for the ?-quenched Zircaloy-4 for which the limit value was reached later at about 5 x 1025 n m-2. Uniform elongation at 588 K showed a minimum at about 5 x 1024 n m-2; beyond this fluence, stress-relieved Zircaloy-4 presented the most marked tendency to increase. Longitudinal direction growth of annealed Zircaloy-4 and longitudinal and transverse direction growth of stress-relieved Zircaloy-4 may be expressed by the formula ? = A(?t)n where n = 0.67 (stress-relieved Zircaloy-4) and n = 0.4 (annealed Zircaloy-4). It is doubtful that the growth is associated with a density change. The stress-relaxation of the zirconium base materials is nearly complete for 4 x 1025 n m-2, with the exception of Zr-1Nb which has an intermediate behavior between those of Zircaloy-4 and Inconel 718.

Download or read book The effects of intergranular constraints on irradiation growth of zircaloy 2 at 320 k written by R. A. Holt and published by . This book was released on 1987 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Amorphization of Precipitates in Zircaloy Under Neutron and Charged Particle Irradiation written by AT. Motta and published by . This book was released on 1991 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: The crystalline-amorphous transformation of the intermetallic precipitates Zr(Cr,Fe)2 and Zr2(Ni,Fe) in Zircaloy under charged-particle and neutron irradiation is studied.

Download or read book The Effects of Anisotropy and Irradiation on the Deformation Behavior of Zircaloy 2 written by and published by . This book was released on 1979 with total page 305 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Corrosion of Electron Irradiated Zr 2 5Nb and Zircaloy 2 written by OT. Woo and published by . This book was released on 2000 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: We used 10-MeV electrons to rapidly produce radiation damage in zirconium alloys, investigated whether electrons produced the same microstructural changes as neutrons, then performed post-irradiation corrosion tests to determine whether electron-irradiated materials displayed similar corrosion behavior to neutron-irradiated materials.