Download or read book Fracture Toughness Characterization of Irradiated F82H in the Transition Region written by H. Tanigawa and published by . This book was released on 2004 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ferritic-martensitic steel F82H is a primary candidate low-activation material for fusion applications, and it is being investigated in the joint U.S. Department of Energy-Japan Atomic Energy Research Institute (U.S. DOE-JAERI) collaboration program. As part of this program, two capsules containing a variety of specimen designs were irradiated at two different temperatures in the Oak Ridge National Laboratory (ORNL) High Flux Isotope Reactor (HFIR). The bottom and top parts of these capsules were loaded with disk-shaped compact tension [DC(T)] specimens that were used for fracture toughness characterization. This small (12.5-mm-diam and of 4.6-mm-thick) DC(T) specimen was developed at ORNL for testing irradiated materials. Six specimens were irradiated in each "low-"and "high-" irradiation temperature capsule up to ~3.8 dpa. Irradiation temperatures were measured by thermocouples. In the low-temperature capsule, three specimens were irradiated at an average temperature of 261°C and another three at 240°C; temperature variation during irradiation was within ±19°C for a given specimen. In the high-temperature capsule, all six specimens were irradiated at an average temperature of 377°C in the bottom part of the capsule; temperature variation during irradiation was within ±30°C for a given specimen. All irradiated specimens failed by cleavage instability. From these data, fracture toughness transition temperatures were evaluated for irradiated F82H steel and compared to unirradiated values. Specimens irradiated at the higher temperature exhibited a relatively modest shift of the fracture toughness transition temperature of ~57°C. However, the shift of fracture toughness transition temperature of specimens irradiated at 250°C was much larger, ~191°C. These results are compared with available tensile and impact Charpy data for this material.
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 Post irradiation Fracture Toughness Characterization of Four Lab melt Plates written by A. L. Hiser and published by . This book was released on 1989 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fracture Toughness and Atom Probe Characterization of a Highly Embrittled RPV Weld written by MA. Sokolov and published by . This book was released on 2004 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Heavy-Section Steel Irradiation Program at Oak Ridge National Laboratory (ORNL) includes a task to investigate the shape of the fracture toughness master curve for reactor pressure vessel steel highly embrittled as a consequence of irradiation exposure. A radiation-sensitive reactor pressure vessel (RPV) weld with intentionally enhanced copper content, designated KS-01, is characterized in terms of static initiation (KIc, KJc) and Charpy impact toughness in the unirradiated and irradiated conditions. The objective of this project is to investigate the ability of highly embrittled material to maintain the shape of the unirradiated transition fracture toughness curve, as well as to examine the ability of the Charpy 41-J shift to predict the fracture toughness shift at such a high level of embrittlement. Irradiation of this weld was performed at the University of Michigan Ford Reactor. Specimens of KS-01 weld were irradiated to about 0.74 x 1019 neutron/cm2 at 288°C. Irradiation resulted in Charpy ductile-to-brittle transition temperature (DBTT) shift of 169°C. It was anticipated that this shift would result in a fracture toughness transition temperature (at 100 MPa?m) in the irradiated condition near or slightly above the pressurized thermal shock screening criterion for weld metals, ToPTS = 129°C. The fracture toughness characterization of KS-01 weld in the unirradiated and irradiated conditions was mainly performed by testing 1T C(T), although some 0.5T C(T) and precracked Charpy specimens were used in this study. The master curve analysis showed that this material exhibited shift of reference fracture toughness transition temperature, To, of 165°C as result of radiation, which is in remarkable agreement with Charpy DBTT shift. The absolute value of To in the irradiated condition was determined to be equal to 139°C. This weld exhibited a low ductile initiation toughness (JQ) after irradiation. It left a relatively narrow temperature window to examine the shape of the transition region. Irradiated median fracture toughness values up to 148 MPa?m follow the master curve shape. However, low toughness brittle fractures occurred at temperatures further above To (To + 61°C) than expected with a leveling of the KJc data from the master curve shape. The microstructure of the weld was characterized with the ORNL's energy-compensated optical position-sensitive atom probe. Atom probe tomography revealed a high number density (~3 x 1024m-3) of Cu-, Mn-, Ni-, Si-, and P-enriched precipitates and a lower number density (~1 x 1023 m-3) of P clusters.
Download or read book A Statistical Analysis of Fracture Toughness of Irradiated Low Alloy Steel Plate and Welds written by JJ. McGowan and published by . This book was released on 1987 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studies of the effects of neutron irradiation on fracture toughness properties of steels have generally included a minimum number of tests for each material condition. The present study attempts to apply statistical analyses with multiple testing at selected temperatures to assess the accuracy and reliability of the results. Fracture toughness test specimens were irradiated in the Bulk Shielding Reactor at Oak Ridge National Laboratory at 288°C to target neutron fluences of 2 x 1023 n/m2 (>1 MeV). The materials were ASTM A533 Grade B Class 1 plate (HSST Plate 02) and four submerged-arc welds representing current nuclear pressure vessel fabrication practice. Both unirradiated and irradiated specimens were tested by two separate laboratories, and multiple tests were conducted at selected temperatures. Statistical analyses permitted determination of material and test variability and an interlaboratory comparison. Behavior in both the transition and upper-shelf regions was studied.
Download or read book Post irradiation Fracture Toughness Characterization of Four Lab melt Plates written by and published by . This book was released on 198? with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fracture Toughness of Ferritic Steels in the Ductile to Brittle Transition Region written by Carlos Berejnoi and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Ferritic steels, as other materials, have different failure modes depending on the temperature. At elevated temperatures, they behave as ductile materials, while at low temperatures they are brittle. There is an intermediate temperature region where these alloys have a failure mode resulting from the competition between cleavage and ductile mechanisms. This region is known as the ductile-to-brittle transition zone. The characterization of fracture resistance of ferritic steels in the ductile-to-brittle transition region is problematic due to scatter in results, as well as size and temperature dependences. American Society for Testing and Materials (ASTM) has standardized the determination of a temperature reference (T0) for the fracture toughness characterization of ferritic steels in this region. This chapter presents the evolution of the statistical treatment of fracture toughness data until the present, including some comments on T0 determination, and some aspects that require a deeper analysis.
Download or read book Statistical Characterization of Fracture in the Transition Region written by JD. Landes and published by . This book was released on 1980 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fracture toughness results are measured in the transition region for an ASTM A471 Ni-Cr-Mo-V steel on two specimen sizes 1T compact tension (CT) and 4T-CT. The results are typical for steels in the transition in that the smaller specimen toughness values are greater than the larger specimen results. Two explanations are given for this behavior. One explanation, based on loss of constraint, suggests that small specimens cannot be used to characterize the toughness of a large structure in the transition region. A second explanation, based on a statistical model, suggests that small specimen results when properly analyzed can be used to characterize the toughness of large structures.
Download or read book Characterization of the Master Curve Based Fracture Toughness of ORNL TSE5 Steel and Unirradiated and Irradiated ASTM A203D 3 5 Ni Steel by the IGCAR Procedure written by P. R. Sreenivasan and published by . This book was released on 2012 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Zero Carbon Energy Kyoto 2010 written by Takeshi Yao and published by Springer Science & Business Media. This book was released on 2011-02-14 with total page 318 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since 2008, the Global Center of Excellence (COE) at Kyoto University, Japan, has been engaged in a program called “Energy Science in the Age of Global Warming—Toward a CO2 Zero-Emission Energy System.” Its aim is to establish an international education and research platform to foster educators, researchers, and policy makers who can develop technologies and propose policies for establishing a CO2 zero-emission society no longer dependent on fossil fuels. It is well known that the energy problem cannot simply be labeled a technological one, as it is also deeply involved with social and economic issues. The establishment of a “low-carbon energy science” as an interdisciplinary field integrating social sciences with natural sciences is necessary. The Global COE is setting out a zero-emission technology roadmap and is promoting socioeconomic studies of energy, studies of new technologies for renewable energies, and research for advanced nuclear energy. It has also established the Global COE Unit for Energy Science Education to support young researchers as they apply their skills and knowledge and a broad international perspective to respond to issues of energy and the environment in our societies. Comprising the proceedings of the Second International Symposium of the Global COE Program, this book follows on the earlier volume Zero-Carbon Energy Kyoto 2009, published in March 2010.
Download or read book Advances in Fracture Toughness Characterization Procedures and in Quantitative Interpretations to Fracture safe Design for Structural Steels written by William S. Pellini and published by . This book was released on 1968 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: The state of knowledge of fracture-safe design for steels is examined in relation to the requirements for achieving practical solutions to general engineering problems. Analytical procedures evolved from fracture mechanics theory are demonstrated to provide for quantitative interpretations of engineering fracture toughness tests. It is thus possible to couple the procedural simplicity which is inherent to engineering tests with the analytical advantages of fracture mechanics theory. The coupling of these two approaches provides for practical advances in fracture-safe design which cover the totality of general engineering problems and requirements. The Charpy V test is shown to have applicability for use in the described fashion primarily in relation to the strength transition for high strength steels. The combined diagrams should serve the needs of both the materials and design fields. (Author).
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 Analysis of the Belgian Surveillance Fracture Toughness Database Using Conventional and Advanced Master Curve Approaches written by Enrico Lucon and published by . This book was released on 2009 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: The "classical" regulatory approach to the analysis of surveillance capsules in nuclear power plants entails an indirect estimate of the fracture toughness of the beltline materials, by inferring rather than measuring their toughness properties. Indeed, the irradiation-induced shift of the fracture toughness curve is assumed to be equal to the shift of the Charpy absorbed energy transition curve at a predefined level (41 J). An alternative surveillance approach, primarily based on direct fracture toughness measurements in the ductile-to-brittle transition region using the Master Curve procedure, has been applied to surveillance materials from several Belgian nuclear power plants in the past 15 years. This has led to the establishment of a significant database, consisting of 292 fracture toughness data points for 23 material conditions (unirradiated materials and surveillance capsules). In this study, different temperature normalization approaches are applied to the available data. The analyses show that data clearly follow the Master Curve formalism. Moreover, it is confirmed that both the static (KIc) and the dynamic (KIR) curves of the ASME Code Section XI provide an effective lower bound to the measured results, although more conservatism is evident when using RTNDT as the normalization parameter. Both the conventional (ASTM E1921-08, "Standard Test Method for Determination of Reference Temperature, TO, for Ferritic Steels in the Transition Range") and advanced (Multi-Modal) Master Curve analyses of the database clearly demonstrate that normalizing data by (T-RTT0) provides the best rationalization of the available information and the most effective representation of the experimental scatter.
Download or read book Characterization of Interfacial Fracture Toughness written by Jianmin Qu and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Extrapolation of Fracture Toughness Data for HT9 Irradiated at 360 390 C written by DS. Gelles and published by . This book was released on 2005 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Following irradiation in the FFTF-AC01 test at 360°C to 5.5 × 1022 n/cm2, two HT9 samples tested at 30°C were measured to have fracture toughness levels of 28.2 and 31.9 MPa m1/2, respectively, whereas a third identical specimen tested at 205°C gave 126 MPa m1/2. Based on testing of notched tensile specimens from the same irradiation test, the low toughness was a result of brittle fracture. A similar low level of toughness has also been demonstrated in HT9 following irradiation at 250°C, and therefore such behavior is reproducible. Using ASTM Standard E 1921-02, which characterizes the fracture toughness of ferritic steels that experience onset of cleavage cracking at instabilities, it is shown that these data can be analyzed by a Master Curve approach, and that the trend of the fracture toughness over a wider range of temperatures can be estimated. Master Curve analysis demonstrates that toughness will remain low over a wide range of temperatures near 30°C, but will degrade only slightly when temperatures drop to −10°C.
Download or read book Advances in Fracture Toughness Characterization Procedures and in Quantitative Interpretations to Fracture safe Design for Structural Steels written by W. S. Pellini and published by . This book was released on 1968 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: The state of knowledge of fracture-safe design for steels is examined in relation to the requirements for achieving practical solutions to general engineering problems. Analytical procedures evolved from fracture mechanics theory are demonstrated to provide for quantitative interpretations of engineering fracture toughness tests. It is thus possible to couple the procedural simplicity which is inherent to engineering tests with the analytical advantages of fracture mechanics theory. The coupling of these two approaches provides for practical advances in fracture-safe design which cover the totality of general engineering problems and requirements. The Charpy V test is shown to have applicability for use in the described fashion primarily in relation to the strength transition for high strength steels. The combined diagrams should serve the needs of both the materials and design fields. (Author).
Download or read book Yield and Toughness Transition Predictions for Irradiated Steels Based on Dislocation Mechanics written by M. Wagenhofer and published by . This book was released on 2001 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: An abundance of empirical data supports the use of the Master Curve, as proposed by Wallin, Saario and Törrönen, to describe the fracture toughness transition behavior of ferritic steels, particularly the notion of a curve shape that is invariant with steel microstructure (other than lattice structure). However, nuclear surveillance programs do not always contain samples of the steel that most limits reactor operations, making direct measurement of fracture toughness impossible. This suggests that a purely empirical argument cannot define the limits of applicability of the Master Curve or validate its use for all conditions of interest. In previous papers a microstructural basis for the existence of a single "Master" fracture toughness transition curve for all ferritic steels was established and limits of applicability have begun to be explored from a theoretical viewpoint. These previous papers established that all steels with the same lattice structure and cleavage fracture mechanism should be expected to adhere to transition behavior that can be defined by a single curve shape with variations in microstructure accounting only for a shift in the transition temperature. In this paper we explore the basis for "Master Curve" validity for irradiated steels by exploring how irradiation affects the microstructure and fracture mode and using the Zerilli-Armstrong constitutive model as the basis for predictions of irradiated steel behavior.
