Download or read book Neutron Irradiation Effects on the Ductile brittle Transition of Ferritic written by and published by . This book was released on 1997 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ferritic/martensitic steels such as the conventional 9Cr-1MoVNb (Fe-9Cr-1Mo-0.25V-0.06Nb-0.1C) and 12Cr-1MoVW (Fe-12Cr-1Mo-0.25V-0.5W-0.5Ni-0.2C) steels have been considered potential structural materials for future fusion power plants. The major obstacle to their use is embrittlement caused by neutron irradiation. Observations on this irradiation embrittlement will be reviewed. Below 425-450°C, neutron irradiation hardens the steels. Hardening reduces ductility, but the major effect is an increase in the ductile-brittle transition temperature (DBTT) and a decrease in the upper-shelf energy, as measured by a Charpy impact test. After irradiation, DBTT values can increase to well above room temperature, thus increasing the chances of brittle rather than ductile fracture. In addition to irradiation hardening, neutrons from the fusion reaction will produce large amounts of helium in the steels used to construct fusion power plant components. Tests to simulate the fusion environment indicate that helium can also affect the toughness. Steels are being developed for fusion applications that have a low DBTT prior to irradiation and then show only a small shift after irradiation. A martensitic 9Cr-2WVTa (nominally Fe-9Cr-2W-0.25V-0.07Ta-0.1C) steel had a much lower DBTT than the conventional 9Cr-1MoVNb steel prior to neutron irradiation and showed a much smaller increase in DBTT after irradiation. 27 refs., 5 figs., 1 tab.

Download or read book Neutron Irradiation Effects on the Ductile brittle Transition of Ferritic martensitic Steels written by and published by . This book was released on 1997 with total page 129 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ferritic/martensitic steels such as the conventional 9Cr-1MoVNb (Fe-9Cr-1Mo-0.25V-0.06Nb-0.1C) and 12Cr-1MoVW (Fe-12Cr-1Mo-0.25V-0.5W-0.5Ni-0.2C) steels have been considered potential structural materials for future fusion power plants. The major obstacle to their use is embrittlement caused by neutron irradiation. Observations on this irradiation embrittlement is reviewed. Below 425-450°C, neutron irradiation hardens the steels. Hardening reduces ductility, but the major effect is an increase in the ductile-brittle transition temperature (DBTT) and a decrease in the upper-shelf energy, as measured by a Charpy impact test. After irradiation, DBTT values can increase to well above room temperature, thus increasing the chances of brittle rather than ductile fracture.

Download or read book The Ductile to Brittle Transition Behavior of Martensitic Steels Neutron Irradiated to 26 Dpa written by W-L Hu and published by . This book was released on 1987 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Charpy impact tests were conducted on specimens made of HT-9 and 9Cr-1Mo in various heat treatment conditions that were irradiated in EBR-II to 26 dpa at 390 to 500°C. The results are compared with previous results on specimens irradiated to 13 dpa. HT-9 base metal irradiated at low temperatures showed a small additional increase in ductile brittle transition temperature and a decrease in upper shelf energy from 13 to 26 dpa. No fluence effect was observed in 9Cr-1Mo base metal. The 9Cr-1Mo weldment showed degraded ductile-to-brittle transition temperature (DBTT) but improved upper shelf energy (USE) response compared to base metal, contrary to previous findings on HT-9. Significant differences were observed in HT-9 base metal between mill annealed material and normalized and tempered material. The highest DBTT for HT-9 alloys was 50°C higher than for the worst case in 9Cr-1Mo alloys. Fractography and hardness measurements were also obtained. Significant differences in fracture appearance were observed in different product forms, although no dependence on fluence was observed. Failure was controlled by the preirradiation microstructure.

Download or read book Report on the Effects of Neutron Radiation on Structural Materials written by M. Kangilaski and published by . This book was released on 1967 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radiation Effects on Toughness of Ferritic Steels for Reactor Vessels written by L. P. Trudeau and published by . This book was released on 1964 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Irradiation Effects on Structural Alloys for Nuclear Reactor Applications written by A. L. Bement and published by ASTM International. This book was released on 1971 with total page 571 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Neutron Irradiation on the Notch Ductility of 15MnTi Steel written by YJ. Aixin and published by . This book was released on 1994 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: 15MnTi steel as a support plate must withstand both the weight of the reactor core of about 100 tons and dynamic loads at 40°C to 50°C. In this study, the steel was embrittled by the neutron irradiation from the reactor core. The ductile-brittle transition temperature was also increased.

Download or read book The Effects of Neutron Irradiation on the Ductile Brittle Transition Temperatures of Weldable Structural Steel Plates written by R. C. Burnett and published by . This book was released on 1958 with total page 18 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 Effects of Radiation on Materials written by Roger E. Stoller and published by ASTM International. This book was released on 1992 with total page 1315 pages. Available in PDF, EPUB and Kindle. Book excerpt: Symposium held in Nashville, Tennessee, June 1990. Almost two-thirds of these 91 papers are authored by researchers outside of the US (including information on research in the former USSR, Japan, and Europe). Topics include: current commercial power reactor systems; microstructural characterization

Download or read book Irradiation Damage of Ferritic written by and published by . This book was released on 1997 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ferritic/martensitic steels were chosen as candidates for future fusion power plants because of their superior swelling resistance and better thermal properties than austenitic stainless steels. For the same reasons, these steels are being considered for the target structure of a spallation neutron source, where the structural materials will experience even more extreme irradiation conditions than expected in a fusion power plant first wall (i.e., high-energy neutrons that produce large amounts of displacement damage and transmutation helium). Extensive studies on the effects of neutron irradiation on the mechanical properties of ferritic/martensitic steels indicate that the major problem involves the effect of irradiation on fracture, as determined by a Charpy impact test. There are indications that helium can affect the impact behavior. Even more helium will be produced in a spallation neutron target material than in the first wall of a fusion power plant, making helium effects a prime concern for both applications. 39 refs., 10 figs.

Download or read book Microstructural Effects of Neutron Irradiation on Ferritic martensitic Stainless Steels written by Terence Stuart Morgan 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 Properties of Reactor Structural Alloys After Neutron Or Particle Irradiation written by C. J. Baroch and published by ASTM International. This book was released on 1975 with total page 625 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mechanical Properties of Four 7 9 Cr Reduced Activation Martensitic Steels After 2 5 Dpa 300 C Irradiation written by E. van Osch and published by . This book was released on 2000 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reduced Activation Ferritic/Martensitic alloys are being developed for application in future thermonuclear fusion reactors. The behavior of the reduced activation martensitic steel F82H-mod was compared with small amounts of related alloys JLF-1, JLF-1B and ORNL-9Cr2WVTa, following irradiation in the High Flux Reactor (HFR) in Petten. Tensile, KLST-type Charpy impact and CT fracture toughness mechanical properties specimens, were neutron irradiated to a dose level of 2-3 dpa at 300°C. Results of post irradiation tensile, miniaturized charpy impact, and static fracture toughness tests are presented and interpreted in terms of irradiation hardening and irradiation induced shift of ductile to brittle transition temperature (DBTT) and reduction of upper shelf energy (USE). The observed irradiation hardening (140 - 170 MPa at 300°C) is moderate, whereas the observed radiation induced shift in DBTT is approximately 150°C for KLST-type impact test specimens for F82H. Similar observations are made for the static fracture toughness tests. For JLF-1B the irradiation hardening is one third higher than for JLF-1, and shift in DBTT for JLF-1B is almost 70% larger than for JLF-1. The difference is attributed to the tenfold larger boron content prior to irradiation.

Download or read book Irradiation Induced Grain Boundary Solute Segregation and Its Effect on Ductile to Brittle Transition Temperature in Reactor Pressure Vessel Steels written by Masatake Yamaguchi and published by . This book was released on 2009 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: A study on grain-boundary segregation and embrittlement in terms of the Charpy ductile-to-brittle transition temperature (DBTT) has been performed for the neutron-irradiated A533B steels with typical contents of impurities of Japanese reactor pressure vessel ones. The neutron irradiation was conducted at 563 K to a fluence of 1.3 x 1024n/m2 (E>1 MeV) using material testing reactors. The neutron irradiation induced the P and Ni segregation and the reduction in C in some cases at grain-boundaries. The increase in the P segregation at high fluence (>5 x 10 23n/m2, E>1 MeV) was less than 0.1 in monolayer coverage for the steels with the bulk content of P not exceeding 0.02 wt%. The hardening more strongly affected the DBTT shift than the P segregation for those steels. The reduction in segregated C that enhances the grain-boundary cohesion by neutron fluence is not large enough to cause the DBTT shift.

Download or read book Effects of Neutron Irradiation and Hydrogen on Ductile brittle Transition Temperatures of V Cr Ti Alloys written by and published by . This book was released on 1993 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of neutron irradiation and hydrogen on the ductile- brittle transition temperatures (DBTTs) of unalloyed vanadium and V-Cr-Ti alloys were determined from Charpy-impact tests on 1/3 ASTM standard size specimens and from impact tests on 3-mm diameter discs. The tests were conducted on specimens containing

Download or read book The Effect of Nuclear Radiation on Structural Metals written by Frederic R. Shober and published by . This book was released on 1961 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of fast-neutron (>1 Mev) irradiation on the mechanical properties of structural metals and alloys was studied. Although the yield strengths and ultimate tensile strengths are increased su stantially for most materials, the ductility suffers severe decreases. This report presents these changes in properties of several structural metals for a number of neutron exposures within the 1.0 x 10 to the 18th power to 5.0 x 10 to the 21st power n/sq cm range. Data summarizing these effects on several classes of materials such as carbon steels, low-alloy steels, stainless steels, Zr-base alloys, ni-base alloys, Al-base alloys, and Ta are given. Additional data which show the influence f irradiation temperatures and of post-irradiation annealing on the radiation-induced property changes are also given and discussed. Increases as great as 175% in yield strength, 100% in ultimate strength, and decreases of 80% in total elongation are reported for fast-neutron exposures as great as 5 10 to the 21st power n/sq cm. (Author).