Download or read book Fracture Toughness of the IEA Heat of F82H Ferritic martensitic Stainless Steel as a Function of Loading Mode written by and published by . This book was released on 1997 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mode I and mixed-mode I/III fracture toughness tests were performed for the IEA heat of the reduced activation ferritic/martensitic stainless steel F82H at ambient temperature in order to provide comparison with previous measurements on a small heat given a different heat treatment. The results showed that heat to heat variations and heat treatment had negligible consequences on Mode I fracture toughness, but behavior during mixed-mode testing showed unexpected instabilities.

Download or read book Effect of Loading Mode on the Fracture Toughness of a Reduced Activation Ferritic martensitic Stainless Steel written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The critical J integrals of mode I (J[sub IC]), mixed-mode I/III (J[sub MC]), and mode III (J[sub IIIC]) were examined for a ferritic stainless steel (F-82H) at ambient temperature. A determination of J[sub MC] was made using modified compact-tension specimens. Different ratios of tension/shear stress were achieved by varying the principal axis of the crack plane between 0 and 55 degrees from the load line. The results showed that J[sub MC]s and tearing moduli (T[sub M]) varied with the crack angles and were lower than their mode I and mode III counterparts. Both the minimum J[sub MC] and T[sub M] occurred at a crack angle between 40 and 50 degrees, where [sigma][sub i]/[sigma][sub iii] was 1.2 to 0.84. The J[sub min] was 240 kJ/m[sup 2], and ratios of J[sub IC]/J[sub min] and J[sub IIIC]/J[sub min] were about 2.1 and 1.9, respectively. Morphology of fracture surfaces was consistent with the change of J[sub MC] and T[sub M] values. While the upper shelf-fracture toughness of F-82H depends on loading mode, the J[sub min] remains very high. Other important considerations include the effect of mixed-mode loading on the DBT temperature, and effects of hydrogen and irradiation on J[sub min].

Download or read book Mixed mode I III Fracture Toughness of a Ferritic martensitic Stainless Steel written by and published by . This book was released on 1993 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: The critical J-integrals of mode I (J{sub IC}), mixed-mode I/III (J{sub MC}), and mode III (J{sub IIIC}) were examined for a ferritic stainless steel (F-82H) at ambient temperature. A determination of J{sub MC} was made using modified compact-tension specimens. Different ratios of tension/shear stress were achieved by varying the principal axis of the crack plane between 0 and 55 degrees from the load line. Results showed that J{sub MC} and tearing modulus (T{sub M}) values varied with the crack angles and were lower than their mode I and mode III counterparts. Both the minimum J{sub MC} and T{sub M} values occurred at a crack angle between 40 and 50 degrees, where the load ratio of [sigma]{sub i}/[sigma]{sub iii} was 1.2 to 0.84. The J{sub min} was 240 Kj/M2, and ratios of J{sub IC}/J{sub min} and J{sub IIIC}/J{sub min} were 2.1 and 1.9, respectively. The morphology of fracture surfaces was consistent with the change of J{sub MC} and T{sub M} values. While the upper shelf-fracture toughness of F-82H depends on loading mode, the J{sub min} remains very high. Other important considerations include the effect of mixed-mode loading on the DBT temperature, and effects of hydrogen and irradiation on J{sub min}.

Download or read book Dependence of Mode I and Mixed Mode I III Fracture Toughness on Temperature for a Ferritic martensitic Stainless Steel written by and published by . This book was released on 1995 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective is to investigate the dependence of mode I and mixed mode I/III fracture toughness on temperature in the range of -95°C to 25°C for a low activation ferritic/martensitic stainless steel (F82-H). Mode I and mixed Mode I/III fracture toughnesses were investigated in the range of -95 to 25°C for a F82-H steel heat-treated in the following way; 1000°C/20 h/air-cooled (AC), 1100°C/7 min/AC, and 700°C/2 h/AC. The results indicate that crack tip plasticity was increased by mixed mode loading, and suggest that at low temperature, mode I fracture toughness is the critical design parameter, but at temperatures above room temperature, expecially concerning fatigure and creep-fatigue crack growth rate, a mixed mode loading may be more harmful than a mode I loading for this steel because a mixed mode loading results in lower fracture toughness and higher crack tip plasticity (or dislocation activity).

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 A Discussion of the Fracture Toughness of Several Stainless Steels in Sheet Form written by F. J. Barone and published by . This book was released on 1963 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Metallurgical Variables Affecting Fracture Toughness in High strength Sheet Alloys written by Carl E. Hartbower and published by . This book was released on 1963 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Using precracked Charpy tests supplemented by center-notched tensile tests, the fracture toughness of five low-alloy and three stainless steel high-strength alloys in sheet form was measured primarily as a function of heat treatment variables such as austenitizing and tempering temperatures. The low alloy steels studied were D6AC (two heats)4340 (martensitic and bainitic conditions), X200 (0.35 and 0.40% carbon), 300M and H11; and the stainless steels were AM 355, PH 15-7Mo and 301. For 4340, in the bainitic condition, the influence of subsequent deformation and aging on fracture toughness was also determined. In addition, preliminary studies of the effect of welding both before and after heat treatment on the toughness of H11, 300M and 4340 were carried out. (Author).

Download or read book Effect of Loading Rate and Thermal Aging on the Fracture Toughness of Stainless Steel Alloys written by WJ. Mills and published by . This book was released on 1989 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of loading rate on the fracture toughness of Types 304 and 316 stainless-steel plate and Type 308 weld before and after thermal aging was characterized using both fracture mechanics and Charpy specimens. Aging at 566°C for 10 000 h reduced static Jc initiation toughness values for both wrought and weld metals by 10 to 20%, and tearing moduli were reduced by 20 to 30%. Under semi-dynamic and dynamic loading conditions, the fracture resistance was not decreased below the static response for either unaged or aged materials. The present results also demonstrated that the large degradation in Charpy V-notch impact energy after aging was not representative of the impact resistance for stainless-steel components containing cracks or crack-life defects. Fractographic examinations revealed that the large loss in Charpy energy was associated with aging-induced microstructural changes that substantially decreased the energy required to initiate a crack from a blunt notch. At very slow strain rates, creep crack growth was found to cause a significant degradation in fracture toughness.

Download or read book A Closer Look at Effects of the Loading Rate on Fracture Toughness in the Ductile to Brittle Transition Regime of a Ferritic Steel written by Hans-Jakob Schindler and published by . This book was released on 2015 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: An increased loading rate causes not only a shift of the ductile-to-brittle transition curve, but also a slight change of the shape of this curve. The latter tends to become steeper as the loading rate increases. This effect was observed even at loading rates that are considered to be quasi-static according to ASTM E1921-13: Standard Test Method for Determination of Reference Temperature, T0, for Ferritic Steels in the Transition Range, Annual Book of ASTM Standards, ASTM International, West Conshohocken, PA, 2013. Actually, the coefficient 0.019 in the exponent of the MC turned out to be substantially higher at elevated loading rates. This means that a basic assumption of the evaluation procedure of ASTM E1921 is not met, which leads to an increased uncertainty of T0 or T0,x, respectively. This effect of is most pronounced in testing at elevated loading rates using the single-temperature option. An improved method to determine the reference temperature is proposed, where the exponent in the median transition curve in ASTM E1921 is considered to be an open parameter. The resulting reference temperatures, denoted as T100 andT100,x, respectively, are expected to be more accurate than standard T0, which is confirmed by comparison with experimental data. Furthermore, the validity requirements for T100 are less restrictive and more suitable than those in ASTM E1921, since they do not depend on the outcome of the tests. Based on the improved data, an improved estimation formula for the rate-induced shift of T0 is derived. Suggestions are made for improvement of ASTM E1921.

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 Development of High Strength and Fracture Toughness in Steels Through Strain Induced Transformations written by J. D. Morrison and published by . This book was released on 1962 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: An investigation was made to determine the effects of variations in alloy content, coldworking temperature, and amount of cold work, on the tensile and toughness properties of metastable austenitic stainless steels. The purpose of this program was to arrive at an alloy composition and processing procedure that results in an optimum combination of strength and toughness in a structural sheet material that can be used in the fabrication of highly stressed structures, such as rocket motor casings. It was found that the optimum combination of high yield strength and fracture toughness is obtained by cold working alloys containing about 0.04% to0.05% carbon. The effect of post-deformation heat treatments on the properties of the cold-worked stainless steels was found to be a function of the amount of deformation. In standard Type 301 stainless steel cold reduced 40% to 50%, precipitation of fine carbides in transformed (martensitic) areas was evident after exposure to 800 F for 24 hr. (Author).

Download or read book Development of High Fracture Toughness in Maraging Steels written by Stephen D. Antolovich and published by . This book was released on 1975 with total page 53 pages. Available in PDF, EPUB and Kindle. Book excerpt: If 300 grade maraging steel is heat-treated to contain a distribution of tough austenite in an aged martensitic matrix, the fracture toughness can be improved significantly with only minimal decreases in the ultimate tensile strength. Studies have been carried out to determine the reasons for this increase. In particular the structure has been characterized by scanning (SEM) and transmission electron microscopy (TEM), plastic zone sizes and shapes have been determined by microhardness and etching techniques, plane-strain crack tip opening displacements have been measured under loading, and fracture surfaces have been examined both by scanning and replica electron fractography. In addition, a survey of the fatigue crack propagation (FCP) characteristics have been carried out. Some testing was done at -196 C. The fracture toughness of the specially treated steel was equivalent to what was obtained for conventionally treated steel at room temperature. This process was extended to the ultra high strength 350 grade steel and again a significant improvement in toughness was obtained although the magnitude of the increase was not as large as was obtained for the 300 grade steel. A model based on the energy absorbed during plastic deformation of the austenite in the plastic enclave ahead of the crack tip has been proposed and is in good agreement with the experimental results. In some cases, heat treatments were used that result in formation of metastable austenite which transforms to martensite at crack tip on loading. This is a mode of plastic deformation that is responsible for very high toughness.

Download or read book Structural Alloys for Nuclear Energy Applications written by Robert Odette and published by Newnes. This book was released on 2019-08-15 with total page 673 pages. Available in PDF, EPUB and Kindle. Book excerpt: High-performance alloys that can withstand operation in hazardous nuclear environments are critical to presentday in-service reactor support and maintenance and are foundational for reactor concepts of the future. With commercial nuclear energy vendors and operators facing the retirement of staff during the coming decades, much of the scholarly knowledge of nuclear materials pursuant to appropriate, impactful, and safe usage is at risk. Led by the multi-award winning editorial team of G. Robert Odette (UCSB) and Steven J. Zinkle (UTK/ORNL) and with contributions from leaders of each alloy discipline, Structural Alloys for Nuclear Energy Applications aids the next generation of researchers and industry staff developing and maintaining steels, nickel-base alloys, zirconium alloys, and other structural alloys in nuclear energy applications. This authoritative reference is a critical acquisition for institutions and individuals seeking state-of-the-art knowledge aided by the editors’ unique personal insight from decades of frontline research, engineering and management. Focuses on in-service irradiation, thermal, mechanical, and chemical performance capabilities. Covers the use of steels and other structural alloys in current fission technology, leading edge Generation-IV fission reactors, and future fusion power reactors. Provides a critical and comprehensive review of the state-of-the-art experimental knowledge base of reactor materials, for applications ranging from engineering safety and lifetime assessments to supporting the development of advanced computational models.

Download or read book Status of Accelerator Driven Systems Research and Technology Development written by International Atomic Energy Agency and published by IAEA Tecdoc. This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the greatest challenges for nuclear energy is how to properly manage the highly radioactive waste generated during irradiation in nuclear reactors. Accelerator Driven Systems (ADSs) may offer new prospects and advantages for the transmutation of such high level nuclear waste. ADS or accelerator driven transmutation of waste (ATW) consists of a high power proton accelerator, a heavy metal spallation target that produces neutrons when bombarded by the high power beam, and a sub-critical core that is neutronically coupled to the spallation target. This publication provides a comprehensive state of the art of the ADS technology by representing the different ADS concepts proposed worldwide in the last 15 years, as well as the related R&D activities and demonstration initiatives carried out at national international level.

Download or read book Magnetic Fusion Technology written by Thomas J. Dolan and published by Springer Science & Business Media. This book was released on 2014-02-10 with total page 816 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetic Fusion Technology describes the technologies that are required for successful development of nuclear fusion power plants using strong magnetic fields. These technologies include: • magnet systems, • plasma heating systems, • control systems, • energy conversion systems, • advanced materials development, • vacuum systems, • cryogenic systems, • plasma diagnostics, • safety systems, and • power plant design studies. Magnetic Fusion Technology will be useful to students and to specialists working in energy research.

Download or read book Fundamentals of Magnetic Thermonuclear Reactor Design written by Vasilij A. Glukhikh and published by Woodhead Publishing. This book was released on 2018-05-21 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fundamentals of Magnetic Thermonuclear Reactor Design is a comprehensive resource on fusion technology and energy systems written by renowned scientists and engineers from the Russian nuclear industry. It brings together a wealth of invaluable experience and knowledge on controlled thermonuclear fusion (CTF) facilities with magnetic plasma confinement – from the first semi-commercial tokamak T-3, to the multi-billion international experimental thermonuclear reactor ITER, now in construction in France. As the INTOR and ITER projects have made an immense contribution in the past few decades, this book focuses on its practical engineering aspects and the basics of technical physics and electrical engineering. Users will gain an understanding of the key ratios between plasma and technical parameters, design streamlining algorithms and engineering solutions. Written by a team of qualified experts who have been involved in the design of thermonuclear reactors for over 50 years Outlines the most important features of the ITER project in France which is building the largest tokamak, including the design, material selection, safety and economic considerations Includes data on how to design magnetic fusion reactors using CAD tools, along with relevant regulatory documents

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