Download or read book Void Swelling in Electron Irradiated Fe Cr Ni Model Alloys written by O. Dimitrov and published by . This book was released on 1987 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: A study of the void swelling produced by 1-MeV electron irradiation in high-purity Fe-Cr-Ni alloys has been performed in order to obtain a better understanding of the composition dependence of swelling in this system. Alloys with 16 wt% chromium and 20 to 75 wt% nickel, with or without helium preinjection, were irradiated in a high-voltage electron microscope, at a displacement rate of 22 dpa/h in the temperature range 370 to 600°C, to maximum damage levels up to 105 dpa. An increase in nickel concentration was found to reduce void density, to increase incubation dose, and to shift the swelling-rate maximum to lower temperatures. A helium preinjection of 70 appm reduces strongly the effect of material composition. The application of a simple void-growth model to the experimental results shows that the changes of point-defect parameters with nickel concentration produce variations of the calculated swelling rate that exhibit the observed trends. However these variations are of only marginal amplitude, as compared with the swelling-rate variations resulting from the observed microstructural changes. The bias factor was found to decrease with decreasing temperature in the 20 wt% Ni alloy; it also decreased at 500°C, with increasing nickel concentration.
Download or read book Radiation induced Changes in Microstructure written by F. A. Garner and published by ASTM International. This book was released on 1987 with total page 919 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Void Swelling in Binary Fe Cr Alloys at 200 DPA written by and published by . This book was released on 1994 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microstructural examinations have been performed on a series of binary Fe-Cr alloys irradiated in the FFTF/MOTA at 425C to 200 dpa. The data represent the highest swelling levels reported in neutron irradiated ferritic alloys. The alloy compositions ranged from 3 to 18% Cr in 3% Cr increments, and the irradiation temperature corresponded to the peak swelling condition for this alloy class. Density measurements showed swelling levels as high as 7.4%, with the highest swelling found in the Fe-9Cr and Fe-6Cr alloys. Microstructural examinations revealed that the highest swelling conditions contained well-developed voids, often as large as 100 nm, and a dislocation network comprised of both 2{sup a}111 and a100 Burgers vectors. Swelling was lower in the other alloys, and the swelling reduction could be correlated with increased precipitation. These results are considered in light of current theories for low swelling in ferritic alloys, but no theory is available to completely explain the results.
Download or read book The Behavior of Solute Segregation and Void Formation in Fe Cr Ni and Fe Cr Mn Steels During Electron Irradiation written by FA. Garner and published by . This book was released on 1987 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: The relative swelling behavior of Fe-Cr-Mn and Fe-Cr-Ni alloys during electron irradiation is shown to be different from that observed in neutron irradiations. This difference appears to be a consequence of the different diffusion behavior of nickel and manganese in response to the operation 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 allows the relative diffusional characteristics of each element to be observed by energy-dispersive X-ray (EDX) measurements across the grain boundary. The influence of helium and minor solutes on swelling was also studied in these experiments and yielded no behavior atypical of that observed in neutron irradiation studies.
Download or read book Behavior of Fe Cr Ni xP yTi Alloys Under Electron He Ion Dual Beam Irradiation written by H. Takahashi and published by . This book was released on 1999 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of helium on microstructural development during dual beam irradiation with electrons/ He+ ions was examined for Fe-16wt%Cr-14wt%Ni-xwt%P-ywt%Ti (x=0, 0.1, y=0, 0.1) model alloys. Irradiation was carried out using a high voltage electron microscope (1000kv) connecting with 300 keV ion accelerator. The simultaneous ion injection rate was 20 at.ppm He/ dpa at 70KeV and irradiation temperatures were 723 K and 773K. In the phosphorus containing alloy, vacancy type dislocation loops were nucleated in the early irradiation stage with electrons beam irradiation. Voids were nucleated from lower dose during electrons/ He+ ions dual beam irradiations. In the titanium contained alloy, under electrons/ He ions dual irradiation, void nucleation was lower comparing to phosphorus containing alloy under electron beam. Furthermore, structural development in alloy containing both titanium and phosphorous was similar to that of alloy with phosphorus and dislocation density was very high. From these results it was clarified that helium strongly influences void nucleation in each alloy as a result of interaction between phosphorus and interstitials.
Download or read book Irradiation Damage in Neutron irradiated Fe Cr Model Alloys written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spinodal like Decomposition and Swelling Induced by Ion Irradiation in Simple Fe Ni and Fe Ni Cr Alloys written by RA. Dodd and published by . This book was released on 1987 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: A previously published correlation between the compositional dependence of neutron-induced swelling at high temperatures in Fe-Ni-Cr alloys and the development of compositional micro-oscillations has also been found in this study of swelling induced by 5-MeV Ni+ ion irradiation. The tendency toward decomposition is strongest in the 35 to 45% nickel range and diminishes in the range of 60 to 75% nickel. Chromium appears to play no role other than as a surrogate for iron. The scale of the micro-oscillation appears to be more sensitive to temperature than displacement rate. One consequence of this decomposition is the occasional formation of precipitate phases upon cooling after irradiation. In Fe-35Ni, cellular martensite is found to form after irradiation at 625, 675, and 725°C. In Fe-60Ni-15Cr irradiated at 625°C an ordered phase that may be Ni3(Fe,Cr) is sometimes formed. The fortuitous formation of these phases allows the visualization of the size and spacing of the compositional modulations.
Download or read book Radiation induced Segregation and the Relationship to Physical Properties in Irradiated Austenitic Alloys written by and published by . This book was released on 2002 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radiation-induced changes in composition are studied because these changes can degrade failure of materials irradiated in nuclear reactors. In this work, the effect of alloy composition on radiation-induced segregation, hardening, and void swelling is presented. Five alloys, Fe-18Cr-8Ni, Fe-16Cr-13Ni, Fe-18Cr-40Ni, Fe-16Cr-13Ni+Mo, and Fe-16Cr-13Ni+Mo+P (all compositions in wt. %), were irradiated with 3.2 MeV protons at 400 C to a dose of 0.5 displacements per atom. The change in grain boundary composition was measured using field emission gun scanning transmission electron microscopy and the hardening was measured using Vickers indentation. Void swelling is calculated from the void size distribution measured using transmission electron microscopy. After irradiation, Cr depletes and Ni enriches at grain boundaries. Increasing bulk Ni concentration causes greater Cr depletion and Ni enrichment at grain boundaries. For alloys with 16 Cr, the addition of P reduces the Cr depletion and Ni enrichment. Hardening does not directly correlate with composition, but a framework for isolating the effect of hardening and segregation on cracking is suggested. The amount of void swelling in the irradiated material is shown to correspond inversely with segregation. Those alloys with greater segregation tend to swell less.
Download or read book NEUTRON INDUCED SWELLING OF Fe Cr BINARY ALLOYS IN FFTF AT 400 DEGREES C written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this effort is to determine the influence of dpa rate, He/dpa ratio and composition on the void swelling of simple binary Fe-Cr alloys. Contrary to the behavior of swelling of model fcc Fe-Cr-Ni alloys irradiated in the same FFTF-MOTA experiment, model bcc Fe-Cr alloys do not exhibit a dependence of swelling on dpa rate at approximately 400 degrees C. This is surprising in that an apparent flux-sensitivity was observed in an earlier comparative irradiation of Fe-Cr binaries conducted in EBR-II and FFTF. The difference in behavior is ascribed to the higher helium generation rates of Fe-Cr alloys in EBR-II compared to that of FFTF, and also the fact that lower dpa rates in FFTF are accompanied by progressively lower helium generation rates.
Download or read book The Question of Saturation of Void Swelling in Fe Cr Ni Austenitic Alloys written by FA. Garner and published by . This book was released on 2000 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Whereas in earlier publications it appeared that a possible saturation of neutron-induced void swelling might be developing at temperatures of 400 and 427°C in annealed Fe-Cr-Ni model alloys in a manner that was dependent on composition, data obtained at higher neutron exposures in EBR-II have led to the conclusion that such an expectation was erroneous. At all temperatures in the range 400-650°C, the neutron induced swelling eventually reaches ~1%/dpa and continues to very high swelling levels thereafter without any hint of saturation.
Download or read book On Radiation induced Segregation and the Compositional Dependence of Swelling in Fe Ni Cr Alloys written by W. G. Wolfer and published by . This book was released on 1982 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1975 with total page 1396 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Radiation on Materials written by R. K. Nanstad and published by ASTM International. This book was released on 1999 with total page 1135 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comprehensive Nuclear Materials written by and published by Elsevier. This book was released on 2020-07-22 with total page 4871 pages. Available in PDF, EPUB and Kindle. Book excerpt: Materials in a nuclear environment are exposed to extreme conditions of radiation, temperature and/or corrosion, and in many cases the combination of these makes the material behavior very different from conventional materials. This is evident for the four major technological challenges the nuclear technology domain is facing currently: (i) long-term operation of existing Generation II nuclear power plants, (ii) the design of the next generation reactors (Generation IV), (iii) the construction of the ITER fusion reactor in Cadarache (France), (iv) and the intermediate and final disposal of nuclear waste. In order to address these challenges, engineers and designers need to know the properties of a wide variety of materials under these conditions and to understand the underlying processes affecting changes in their behavior, in order to assess their performance and to determine the limits of operation. Comprehensive Nuclear Materials, Second Edition, Seven Volume Set provides broad ranging, validated summaries of all the major topics in the field of nuclear material research for fission as well as fusion reactor systems. Attention is given to the fundamental scientific aspects of nuclear materials: fuel and structural materials for fission reactors, waste materials, and materials for fusion reactors. The articles are written at a level that allows undergraduate students to understand the material, while providing active researchers with a ready reference resource of information. Most of the chapters from the first Edition have been revised and updated and a significant number of new topics are covered in completely new material. During the ten years between the two editions, the challenge for applications of nuclear materials has been significantly impacted by world events, public awareness, and technological innovation. Materials play a key role as enablers of new technologies, and we trust that this new edition of Comprehensive Nuclear Materials has captured the key recent developments. Critically reviews the major classes and functions of materials, supporting the selection, assessment, validation and engineering of materials in extreme nuclear environments Comprehensive resource for up-to-date and authoritative information which is not always available elsewhere, even in journals Provides an in-depth treatment of materials modeling and simulation, with a specific focus on nuclear issues Serves as an excellent entry point for students and researchers new to the field
Download or read book Energy Research Abstracts written by and published by . This book was released on 1994-05 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Irradiation Effects on the Microstructure on Properties of Metals written by ASTM International Symposium on Effects of Radiation on Structural Materials and published by ASTM International. This book was released on 1976 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Radiation on Materials written by N. H. Packan and published by ASTM International. This book was released on 1990 with total page 679 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation Effects of Radiation on Materials: Fourteenth International Symposium was presented at Andover, MA, June 1988. The symposium was sponsored by ASTM Committee E-10 on Nuclear Technology and Applications. The papers from the first three days of the symposium appear in the two volumes of this publication. Volume I encompasses radiation damage- induced microstructures; point defect, solute, and gas atom effects; atomic-level measurement techniques; and applications of theory. Volume II includes mechanical behavior, all papers dealing with pressure-vessel steels, breeder reactor components, dosimetry, and nuclear fuels. The fourth day of the symposium was devoted to the single topic of reduced-activation materials (see TK9204). The two volumes are separately sold at $127 and $128 respectively; each is independently indexed. Annotation copyrighted by Book News, Inc., Portland, OR.
