Download or read book Microstructural Evolution of Austenitic Stainless Steels Irradiated in a Fast Reactor written by OV. Borodin and published by . This book was released on 1996 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Analysis of the microstructure of the stainless steels 16Cr15Ni3MoNb and 18Cr10NiTi, irradiated at temperatures where changes in phase stability occur due to radiation-induced segregation, shows that the stability of second-phase particles depends on the structure of particle-matrix interface.

Download or read book Microstructural Evolution in Fast neutron irradiated Austenitic Stainless Steels written by and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The present work has focused on the specific problem of fast-neutron-induced radiation damage to austenitic stainless steels. These steels are used as structural materials in current fast fission reactors and are proposed for use in future fusion reactors. Two primary components of the radiation damage are atomic displacements (in units of displacements per atom, or dpa) and the generation of helium by nuclear transmutation reactions. The radiation environment can be characterized by the ratio of helium to displacement production, the so-called He/dpa ratio. Radiation damage is evidenced microscopically by a complex microstructural evolution and macroscopically by density changes and altered mechanical properties. The purpose of this work was to provide additional understanding about mechanisms that determine microstructural evolution in current fast reactor environments and to identify the sensitivity of this evolution to changes in the He/dpa ratio. This latter sensitivity is of interest because the He/dpa ratio in a fusion reactor first wall will be about 30 times that in fast reactor fuel cladding. The approach followed in the present work was to use a combination of theoretical and experimental analysis. The experimental component of the work primarily involved the examination by transmission electron microscopy of specimens of a model austenitic alloy that had been irradiated in the Oak Ridge Research Reactor. A major aspect of the theoretical work was the development of a comprehensive model of microstructural evolution. This included explicit models for the evolution of the major extended defects observed in neutron irradiated steels: cavities, Frank faulted loops and the dislocation network. 340 refs., 95 figs., 18 tabs.

Download or read book A Composite Model of Microstructural Evolution in Austenitic Stainless Steel Under Fast Neutron Irradiation written by GR. Odette and published by . This book was released on 1987 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: A rate-theory-based model has been developed which includes the simultaneous evolution of the dislocation and cavity components of the microstructure of irradiated austenitic stainless steels. Previous work has generally focused on developing models for void swelling while neglecting the time dependence of the dislocation structure. These models have broadened our understanding of the physical processes that give rise to swelling, for example, the role of helium and void formation from critically-sized bubbles. That work has also demonstrated some predictive capability by successful calibration to fit the results of fast reactor swelling data. However, considerable uncertainty about the values of key parameters in these models limits their usefulness as predictive tools. Hence, the use of such models to extrapolate fission reactor swelling data to fusion reactor conditions is compromised.

Download or read book Composite Model of Microstructural Evolution in Austenitic Stainless Steel Under Fast Neutron Irradiation written by and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A rate-theory-based model has been developed which includes the simultaneous evolution of the dislocation and cavity components of the microstructure of irradiated austenitic stainless steels. Previous work has generally focused on developing models for void swelling while neglecting the time dependence of the dislocation structure. These models have broadened our understanding of the physical processes that give rise to swelling, e.g., the role of helium and void formation from critically-sized bubbles. That work has also demonstrated some predictive capability by successful calibration to fit the results of fast reactor swelling data. However, considerable uncertainty about the values of key parameters in these models limits their usefulness as predictive tools. Hence the use of such models to extrapolate fission reactor swelling data to fusion reactor conditions is compromised.

Download or read book Microstructural Evolution in Fast neutron irradiated Austenitic Stainless Steels written by Roger E. Stoller and published by . This book was released on 1987 with total page 357 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Microstructural Evolution in an Austenitic Stainless Steel Fusion Reactor First Wall written by and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A detailed rate-theory-based model of microstructural evolution under fast neutron irradiation has been developed. The prominent new aspect of this model is a treatment of dislocation evolution in which Frank faulted loops nucleate, grow and unfault to provide a source for network dislocations while the dislocation network can be simultaneously annihilated by a climb/glide process. The predictions of this model compare very favorably with the observed dose and temperature dependence of these key microstructural features over a broad range. This new description of dislocation evolution has been coupled with a previously developed model of cavity evolution and good agreement has been obtained between the predictions of the composite model and fast reactor swelling data as well. The results from the composite model also reveal that the various components of the irradiation-induced microstructure evolve in a highly coupled manner. The predictions of the composite model are more sensitive to parametric variations than more simple models. Hence, its value as a tool in data analysis and extrapolation is enhanced.

Download or read book Official Communiqu of the 4821st closed Meeting of the Security Council Held in Private at Headquarters New York on Tuesday 9 September 2003 written by and published by . This book was released on 2003 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Microstructure Evolution in Proton irradiated Austenitic Fe Cr Ni Alloys Under LWR Core Conditions written by Jian Gan and published by . This book was released on 1999 with total page 710 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Observation and Interpretation of Microstructural Evolution and Swelling in Austenitic Steels Under Irradiation written by N. Sekimura and published by . This book was released on 1994 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: Irradiation behavior of model austenitic steels is investigated to establish mechanistic modeling of swelling and other property changes under irradiation. Neutron irradiation experiments were performed using Material Open Test Assembly (MOTA) at 693, 793 and 873 K to 35 to 40 dpa in the Fast Flux Test Facility (FFTF) cycles 10 and 11. Cavity formation and dislocation development were quantitatively estimated to evaluate the effect of temperature history on the microstructural evolution under irradiation in fission reactors. Fine dislocation loops observed in the matrix of the alloys irradiated in cycle 10 were considered to come from the low-temperature irradiation during the reactor shut-down at the end of the cycle. Very few small loops were detected in identical specimens irradiated in FFTF cycle 11 where the reactor power and temperature were simultaneously decreased a short time during the shut-down.

Download or read book Microstructural Development of Titanium Modified Austenitic Stainless Steel Under Neutron Irradiation in HFIR Up to 57 Dpa written by S. Hamada and published by . This book was released on 1990 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Japanese prime candidate alloy (JPCA). a titanium-modified austenitic stainless steel, has shown good performance after irradiation in the high flux isotope reactor (HFIR) up to 34 dpa at 300 to 600°C, but considerable void swelling develops in solution annealed (SA) JPCA after irradiation to 57 dpa at 500°C. However, cold worked (CW) or cold worked and aged (CW + A) JPCA still demonstrates good performance after similar irradiation. Swelling resistance appears to depend strongly on the behavior of fine titanium-rich MC precipitates. This paper describes the microstructural evolution process observed in the JPCA steel during HFIR irradiation. The onset of rapid void swelling was related to MC precipitate dissolution, and the instability of the MC was interpreted in terms of a model involving the build and subsequent effects of a solute segregation zone in the matrix surrounding the precipitate particle.

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 Microstructural Evolution of Type 304 and 316 Stainless Steels Under Neutron Irradiation at LWR Relevant Conditions written by and published by . This book was released on 2015 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Extension of light water reactors' useful life will expose austenitic internal core components to irradiation damage levels beyond 100 displacements per atom (dpa), which will lead to profound microstructural evolution and consequent degradation of macroscopic properties. Microstructural evolution, including Frank loops, cavities, precipitates, and segregation at boundaries and the resultant radiation hardening in type 304 and 316 stainless steel (SS) variants, were studied in this work via experimental characterization and multiple simulation methods. Experimental data for up to 40 heats of type 304SS and 316SS variants irradiated in different reactors to 0.6-120 dpa at 275-375°C were either generated from this work or collected from literature reports. These experimental data were then combined with models of Frank loop and cavity evolution, computational thermodynamics and precipitation, and ab initio and rate theory integrated radiation-induced segregation models to provide insights into microstructural evolution and degradation at higher radiation doses.

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 Microstructural Evolution of Austenitic Stainless Steels Irradiated to 17 Dpa in Spectrally Tailored Experiment of the ORR and HFIR at 400 degrees C written by and published by . This book was released on 1997 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The microstructural evolution of austenitic JPCA aged and solution annealed JPCA, 316R, C, K, and HP steels irradiated at 400°C in spectrally tailored experiments of the ORR and HFIR has been investigated. The helium generation rates were about 12-16 appm He/dpa on the average up to 17.3 dpa. The number densities and average diameters of dislocation loops in the steels have ranges of 3.3 x 1021 m−3 and 15.2-26.3 nm, respectively, except for HP steel for which they are 1.1 x 1023 m−3 and 8.0 nm. Precipitates are formed in all steels except for HP steel, and the number densities and average diameters have ranges of 5.2 x 102° - 7.7 x 1021 m−3 and 3.4- 19.3 nm, respectively. In the 216R, C, and K steels, the precipitates are also formed at grain boundaries, and the mean sizes of these are about 110, 50, and 50 nm, respectively. The number densities of cavities are about 1 x 1022 m−3 in all the steels. The swelling is low in the steels which form the precipitates.

Download or read book Structural Materials for Generation IV Nuclear Reactors written by Pascal Yvon and published by Woodhead Publishing. This book was released on 2016-08-27 with total page 686 pages. Available in PDF, EPUB and Kindle. Book excerpt: Operating at a high level of fuel efficiency, safety, proliferation-resistance, sustainability and cost, generation IV nuclear reactors promise enhanced features to an energy resource which is already seen as an outstanding source of reliable base load power. The performance and reliability of materials when subjected to the higher neutron doses and extremely corrosive higher temperature environments that will be found in generation IV nuclear reactors are essential areas of study, as key considerations for the successful development of generation IV reactors are suitable structural materials for both in-core and out-of-core applications. Structural Materials for Generation IV Nuclear Reactors explores the current state-of-the art in these areas. Part One reviews the materials, requirements and challenges in generation IV systems. Part Two presents the core materials with chapters on irradiation resistant austenitic steels, ODS/FM steels and refractory metals amongst others. Part Three looks at out-of-core materials. Structural Materials for Generation IV Nuclear Reactors is an essential reference text for professional scientists, engineers and postgraduate researchers involved in the development of generation IV nuclear reactors. - Introduces the higher neutron doses and extremely corrosive higher temperature environments that will be found in generation IV nuclear reactors and implications for structural materials - Contains chapters on the key core and out-of-core materials, from steels to advanced micro-laminates - Written by an expert in that particular area

Download or read book The Microstructural Evolution and Swelling Behavior of Type 316 Stainless Steel Irradiated in HFIR written by S. Hamada and published by . This book was released on 1990 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Solution annealed (SA) and 20% cold worked (CW) Type 316 (UNS S 31600) stainless steels were irradiated in the high flux isotope reactor (HFIR) to 55 dpa and to 3445 appm helium at 300 to 500°C. The irradiated specimens were examined by transmission electron microscopy (TEM) to evaluate microstructural evolution. At irradiation temperatures of 400°C and below, there was very little difference in the microstructural and swelling behavior between SA and CW material. A high concentration of fine bubbles was uniformly dispersed in the matrix. Swelling was very low (

Download or read book Microstructural Stability of Fast Reactor Irradiated 10 12 Cr Ferritic Martensitic Stainless Steels written by EA. Little and published by . This book was released on 1982 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: The strength and microstructural stability of three 10-12%Cr ferritic-martensitic stainless steels have been characterised following fast reactor irradiation to damage levels of 30 displacements per atom (dpa) at temperatures in the range 380°-615°C.