Download or read book Determination of the Lower Temperature Limit of Void Swelling of Stainless Steels at PWR Relevant Displacement Rates written by SI. Porollo and published by . This book was released on 2004 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent studies associated with light water reactors (LWR) in both the USA and Russia have raised the question of void swelling in austenitic components of core internals. One question of particular interest is the range of temperatures over which voids can develop, especially the lowest temperature. To address this question a flow restrictor component manufactured from annealed X18H9T was removed from the reflector region of the BN-350 fast reactor, located in Kazakhstan. During operation this component spanned temperatures and dpa rates of direct interest to pressurized water reactors (PWRs) in the West and VVERs in Russia. This steel is analogous to AISI 321 and is used in Russian reactors for applications where AISI 304 would be used in the West and in Japan.
Download or read book Determination of the Lower Temperature Limit of Void Swelling of Stainless Steels at Relatively Low Displacement Rates written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: An issue of current interest to PWRs is the possibility that void swelling of austenitic near-core internal components may exert some deleterious effect on component functionality, particularly during extended operation to 60 years. A similar concern has also been raised for water-cooled fusion devices. One question of particular interest is the range of temperature over which void swelling can occur, since the internal components experience temperatures from ~290 to perhaps as high as 390 degrees C in some limited locations. This question was addressed using a flow restrictor component from the low-flux breeder zone of the BN-350 fast reactor in Kazakhstan. This component was constructed of annealed 12X18H10T, an alloy similar to AISI 321 which is used in Russian reactors for applications where AISI 304L would be used in comparable Western and Japanese reactors. Extensive sectioning to produce 114 separate specimens, followed by examination of the radiation-induced microstructure showed that void swelling in the range of temperatures and dpa rates of PWR interest occurs down to ~305 degrees C. At 330 degrees C the swelling reached ~1% at 20 dpa. Comparison of these data with other published results from Russian LWR reactors at
Download or read book Proceedings of the 18th International Conference on Environmental Degradation of Materials in Nuclear Power Systems Water Reactors written by John H. Jackson and published by Springer. This book was released on 2018-12-20 with total page 2460 pages. Available in PDF, EPUB and Kindle. Book excerpt: This two-volume set represents a collection of papers presented at the 18th International Conference on Environmental Degradation of Materials in Nuclear Power Systems – Water Reactors. The purpose of this conference series is to foster an exchange of ideas about problems and their remedies in water-cooled nuclear power plants of today and the future. Contributions cover problems facing nickel-based alloys, stainless steels, pressure vessel and piping steels, zirconium alloys, and other alloys in water environments of relevance. Components covered include pressure boundary components, reactor vessels and internals, steam generators, fuel cladding, irradiated components, fuel storage containers, and balance of plant components and systems.
Download or read book Understanding and Mitigating Ageing in Nuclear Power Plants written by Philip G Tipping and published by Elsevier. This book was released on 2010-10-26 with total page 953 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plant life management (PLiM) is a methodology focussed on the safety-first management of nuclear power plants over their entire lifetime. It incorporates and builds upon the usual periodic safety reviews and licence renewals as part of an overall framework designed to assist plant operators and regulators in assessing the operating conditions of a nuclear power plant, and establishing the technical and economic requirements for safe, long-term operation. Understanding and mitigating ageing in nuclear power plants critically reviews the fundamental ageing-degradation mechanisms of materials used in nuclear power plant structures, systems and components (SSC), along with their relevant analysis and mitigation paths, as well as reactor-type specific PLiM practices. Obsolescence and other less obvious ageing-related aspects in nuclear power plant operation are also examined in depth. Part one introduces the reader to the role of nuclear power in the global energy mix, and the importance and relevance of plant life management for the safety regulation and economics of nuclear power plants. Key ageing degradation mechanisms and their effects in nuclear power plant systems, structures and components are reviewed in part two, along with routes taken to characterise and analyse the ageing of materials and to mitigate or eliminate ageing degradation effects. Part three reviews analysis, monitoring and modelling techniques applicable to the study of nuclear power plant materials, as well as the application of advanced systems, structures and components in nuclear power plants. Finally, Part IV reviews the particular ageing degradation issues, plant designs, and application of plant life management (PLiM) practices in a range of commercial nuclear reactor types. With its distinguished international team of contributors, Understanding and mitigating ageing in nuclear power plants is a standard reference for all nuclear plant designers, operators, and nuclear safety and materials professionals and researchers. Introduces the reader to the role of nuclear power in the global energy mix Reviews the fundamental ageing-degradation mechanisms of materials used in nuclear power plant structures, systems and components (SSC) Examines topics including elimination of ageing effects, plant design, and the application of plant life management (PLiM) practices in a range of commercial nuclear reactor types
Download or read book Effects of Radiation on Materials written by Martin L. Grossbeck and published by ASTM International. This book was released on 2004 with total page 767 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Void Swelling at Low Displacement Rates in Annealed X18H10T Stainless Steel at 4 to 56 DPA and 280 332 Degrees Centigrade written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Various components of pressurized water power reactors (PWRs) and some proposed fusion devices such as ITER will operate at lower temperatures and displacement rates than are encountered in many test reactors such as EBR-II, FFTF and HFIR. The question arises if the presence and magnitude of void swelling can be predicted for such irradiation environments. Data on Russian steel can be used to address part of this question. In reactor applications where Western countries typically use annealed AISI 304 stainless steel, it is the Russian practice to use annealed X18H10T, a titanium-stabilized 18Cr-10Ni stainless steel analogous to AISI 321. Using a flow restrictor component from the low-flux breeder zone of the BN-350 reactor in Kazakhstan, it was possible to examine the behavior of void swelling at relatively low temperatures and low displacement rates after 12 years of irradiation. The temperature of this component ranged from 270-340 degrees centigrade with a peak dose rate of 1.6 x 10−7 power dpa/sec and a peak dose of 56 dpa. Careful sectioning of the component has yielded a large number of microscopy specimens over a ITER-relevant range of temperatures and displacement rates. Microstructural data are presented and show that void swelling at 10 to 50 dpa persists down to (almost equal to)306 degrees centigrade for dose rates on the order of 1 x 10−7 power dpa/sec.
Download or read book Assessment of Void Swelling in Austenitic Stainless Steel PWR Core Internals written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: As many pressurized water reactors (PWRs) age and life extension of the aged plants is considered, void swelling behavior of austenitic stainless steel (SS) core internals has become the subject of increasing attention. In this report, the available database on void swelling and density change of austenitic SSs was critically reviewed. Irradiation conditions, test procedures, and microstructural characteristics were carefully examined, and key factors that are important to determine the relevance of the database to PWR conditions were evaluated. Most swelling data were obtained from steels irradiated in fast breeder reactors at temperatures>385 C and at dose rates that are orders of magnitude higher than PWR dose rates. Even for a given irradiation temperature and given steel, the integral effects of dose and dose rate on void swelling should not be separated. It is incorrect to extrapolate swelling data on the basis of 'progressive compounded multiplication' of separate effects of factors such as dose, dose rate, temperature, steel composition, and fabrication procedure. Therefore, the fast reactor data should not be extrapolated to determine credible void swelling behavior for PWR end-of-life (EOL) or life-extension conditions. Although the void swelling data extracted from fast reactor studies is extensive and conclusive, only limited amounts of swelling data and information have been obtained on microstructural characteristics from discharged PWR internals or steels irradiated at temperatures and at dose rates comparable to those of a PWR. Based on this relatively small amount of information, swelling in thin-walled tubes and baffle bolts in a PWR is not considered a concern. As additional data and relevant research becomes available, the newer results should be integrated with existing data, and the worthiness of this conclusion should continue to be scrutinized. PWR baffle reentrant corners are the most likely location to experience high swelling rates, and hence, high swelling at EOL, especially in internal regions of small volume where irradiation temperature is high. However, it is considered unlikely that void swelling in a reentrant corner will exceed the threshold level of (almost equal to)4% beyond which the swelling rate reaches the steady state rate of 1%/dpa. However, this estimation is only preliminary, and a more accurate quantification of maximum temperature of reentrant corners at EOL and life-extension situations would be useful.
Download or read book Void Swelling Behavior of Types 304 and 316 Stainless Steel Irradiated with 4 MeV Ni Ions written by SG. McDonald and published by . This book was released on 1973 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: A detailed study has been made of the void and dislocation microstructure of Types 304 and 316 stainless steel irradiated with 4-MeV 58N+ at a displacement rate of 5 x 10-3 dpa/s-1. The range of dosages investigated were 20 to 350 dpa at 525 C (977 F) and 20 to 250 dpa at 600 C (1112 F) for Type 304 stainless steel and 20 to 250 dpa at 525 C for Type 316. The maximum swelling data for Type 304 stainless steel may be represented by a power-law dependence on-dosage with exponents of 1.4 and 1.8 at 525 and 600 C, respectively. The swelling at 600 C, which is much greater than that at 525 C, is due to the more rapid growth of voids at the higher temperature. No evidence of a reduction in swelling rate at high dosages was found at either temperature. The swelling of Type 316 stainless steel shows a tendency to be lower than that of Type 304 and, at higher dosages, is a factor of two less. In 20 percent cold-worked Type 316 stainless steel, swelling was suppressed until the dislocation structure was recovered.
Download or read book Temperature Shift of Void Swelling Observed in Annealed Fe 18Cr 10Ni Ti Stainless Steel Irradiated in the Reflector Region of BOR 60 written by VK. Shamardin and published by . This book was released on 2000 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: Evidence has been provided to support the "temperature-shift" concept of swelling. The swelling of annealed X18H10T stainless steel in the BOR-60 fast reactor at PWR-relevant dpa rates was found to be higher than predicted by a swelling equation developed from data obtained at dpa rates almost an order of magnitude higher. These data were derived from identical hexagonal wrappers irradiated in both in-core and reflector positions. Based on these results, irradiation in PWRs would yield higher swelling to lower temperatures than would occur in core regions of fast reactors.
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1976 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modeling of Void Swelling in Irradiated Steels written by BB. Glasgow and published by . This book was released on 1985 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: The theory of void swelling in irradiated steels has been critically re-examined and a model has been developed from first principles for such fundamental parameters as the bias factors for dislocations and voids, relaxation volumes for interstitials and vacancies, and migration and formation energies for interstitials and vacancies. Four types of growth mechanisms are modeled: self-interstitial emission, loop punching, thermal vacancy exchange, and bias driven growth. The net bias of the system is allowed to change continuously with the evolving microstructure. Combining these growth mechanisms has resulted in a swelling model capable of reproducing some important features of the observed swelling behavior in austenitic stainless steels. For austenitic stainless steels, the model predicts bias driven growth for temperatures between 300°C and 600°C. The long-term swelling rate in this temperature range is roughly independent of temperature and helium concentration and is between 0.7%/dpa (displacements per atom) and 1.3%/dpa. For ferrite phase, the model predicts bias driven growth for temperatures between 300°C and 500°C. However, for this class of steel, the swelling rate is at or below 0.3%/dpa. For bias driven growth, it has been shown that the interstitial and vacancy relaxation volumes ultimately determine the maximum possible swelling rate. It is for this reason that the model predicts a much lower swelling rate for ferrite phase than for austenitic stainless steels.
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1972 with total page 1036 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effects of Radiation on Materials written by Margaret L. Hamilton and published by ASTM International. This book was released on 2000 with total page 1266 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Low Temperature Swelling in Austenitic Stainless Steels written by Y. Katoh and published by . This book was released on 1999 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Major portions of structural materials of near-term fusion blankets and light water reactor core components are subject to neutron irradiation at low temperatures and low fluxes compared to those in typical void swelling studies using fast reactors. Observed swelling in austenitic stainless steels at temperatures below 673K are generally very small under typical fast reactor irradiation conditions, however, the amount of swelling might be significantly influenced by neutron flux, helium generation rate, etc. In this work, using a reaction rate theory model of swelling, the influences of such key irradiation parameters on low temperature swelling behavior in austenitic stainless steels will be demonstrated to aid the evaluation of swelling at low temperature and low neutron flux conditions.
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 Swelling of AISI Type 304L Stainless Steel in Response to Simultaneous Variations in Stress and Displacement Rate written by FA. Garner and published by . This book was released on 1985 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: The void swelling of annealed AISI Type 304L stainless steel was studied to determine the effects of simultaneous variations in several environmental variables, namely, applied stress and displacement rate. It was found that the transient regime of swelling was modified by both variables in much the same way as previously observed in single-variable experiments. Lower displacement rates and applied tensile stresses shortened the transient regime of swelling. In addition, it was discovered that the simultaneous application of lower dose rates and applied stresses shortened the transient regime to no lower than that observed in the unstressed pure iron-nickel-chromium ternary system, or ~10 displacements per atom (dpa). This implies that the 10 dpa transient may be a generic minimum for iron-based austenitic alloys. Stress and displacement rate appear to act on a common swelling control mechanism, most likely the effectiveness of swelling-inhibitive solutes on void nucleation.
Download or read book Physics Briefs written by and published by . This book was released on 1994 with total page 916 pages. Available in PDF, EPUB and Kindle. Book excerpt:
