Download or read book Influence of Phosphorus on Thermal and Neutron Embrittlement of Pressure Vessel Steels written by H. Horowitz and published by . This book was released on 1993 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: In conjunction with an international study coordinated by the International Atomic Energy Agency (IAEA), a review was made of three Japanese model steels with different phosphorus and copper contents irradiated at 5.1019 n • cm-2 (E > 1 MeV) to explain the influence of phosphorus on the thermal and neutron embrittlement of steels.
Download or read book Influence of Thermal Neutrons on the Hardening and Embrittlement of Plate Steels written by MR. Wootton and published by . This book was released on 2000 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: A series of C-Mn pressure vessel plates and other steels containing various levels of copper, phosphorus and boron were irradiated at 240°C in two differing neutron spectra in the Halden reactor. Hardening and embrittlement data obtained after exposure in a highly thermalised neutron spectrum with dpathermal(>1keV)/dpafast(
Download or read book Radiation Embrittlement of Nuclear Reactor Pressure Vessel Steels written by Lendell E. Steele and published by ASTM International. This book was released on 1993 with total page 405 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Phosphorus Segregation and Intergranular Embrittlement in Thermally Aged and Neutron Irradiated Reactor Pressure Vessel Steels written by Masahide Suzuki and published by . This book was released on 2007 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: A study on phosphorus (P) segregation at grain boundaries and intergranular embrittlement of reactor pressure vessel steels due to thermal aging and neutron irradiation has been performed for A533B steel plates and weld metals doped with different bulk levels of P. The initial P concentration at grain boundaries of these materials determined by scanning Auger microscopy ranged from 9 to 33 %. The materials thermally aged at temperatures ranging from 450 to 550°C for up to 10000 h exhibited increases in P concentration described by the McLean's equation. A linear correlation was obtained between P concentration and Charpy 41 J transition temperature (T41J). Fracture toughness tests in the ductile-to-brittle transition temperature region have been conducted by the Master Curve method using 1T-CT specimens. The material subject to intergranular embrittlement exhibited the dual fracture toughness distributions typically observed in inhomogeneous materials. This was probably due to two types of initiation of cleavage and intergranular fracture. The lower tail analysis based on the Master Curve method enabled conservative fracture toughness estimates by fitting the lower fracture toughness arising from intergranular fracture. The relation between median KJc values estimated from the lower tail analysis and temperature appeared to follow the Master Curve. For neutron irradiated materials up to a fluence of 6.9×1019 n/cm2 (E>1 MeV) at 290°C by the Japan Materials Testing Reactor, an increase in grain boundary P segregation associated with decrease in carbon segregation was observed with increasing fluence. Relative significant hardening was recognized for the material with high bulk P content. Shifts in the reference temperature T0 and T41J were comparable for the thermally aged and irradiated materials.
Download or read book Effects of Microstructure and Thermal Aging on Neutron Irradiation Embrittlement of 21 4Cr 1Mo Steel for a Nuclear Pressure Vessel written by M. Suzuki and published by . This book was released on 1987 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plate, weld, and heat-affected zone (HAZ) materials of 21⁄4Cr-1Mo steels, designated as ASTM A387 Grade 22 Cl.1, and Cl.2 were irradiated at around 400°C to a fluence of about 2 x 1018 n/cm2 (E > 1 MeV). A387 Grade 22 Cl.2 with bainite has a lower susceptibility to neutron irradiation embrittlement than A387 Grade 22 Cl.1 with ferrite plus bainite. The anomalous ductile to brittle transition behavior of A387 Grade 22 Cl.2 was explained by taking into account the parameter ky, which is a constant in the Cottrell-Petch equation. It is concluded that there does not exist any strong interaction between thermal aging embrittlement and neutron irradiation embrittlement.
Download or read book Effects of Nickel on Irradiation Embrittlement of Light Water Reactor Pressure Vessel Steels written by International Atomic Energy Agency and published by IAEA. This book was released on 2005 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication sets out the findings of a co-ordinated research project to determine the influence of the mechanism of the deterioration effect in radiation embrittlement of reactor pressure vessel steels with a high nickel content in nuclear power plants, including procurement of materials, determination of mechanical properties, irradiation and testing of specimens, and microstructural characterisation.
Download or read book Review of Phosphorus Segregation and Intergranular Embrittlement in Reactor Pressure Vessel Steels written by WL. Server and published by . This book was released on 2001 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper presents a systematic review of the behavior of phosphorus (P), highlighting the implications of P segregation to grain boundaries under neutron irradiation. The review focuses on Mn-Mo-Ni steels employed in US pressurized water reactors (PWRs), and other PWRs worldwide. Segregation of P to grain boundaries in reactor pressure vessel (RPV) steels can occur during fabrication (especially during the slow cooling stage of a post-weld heat treatment), and as a result of in-service exposure to high operating temperature and irradiation. This segregation of P to grain boundaries can promote a change in the brittle fracture mode from transgranular (TGF) to intergranular (IGF), and a degradation in the mechanical properties. In US RPV steels, most data are on thermal aging of the heat-affected zone (HAZ). Studies in coarse-grained HAZ have shown that the embrittlement arising from segregation of P to grain boundaries is approximately linearly related to the proportion of the brittle fracture that is IGF, and/or the P concentration at the grain boundary. Data are sparse on the effect of irradiation at 288°C on P segregation, and on the contribution of IGF to the total shift in the 41J transition temperature, T41J. In general, the bulk P content appears to be less than about 0.028 wt% P, with base metals having lower levels than weldments. In addition, the consequences of vessel annealing are considered at temperatures around 475°C. It is certain that the annealing treatment will have the consequence of reducing the irradiation hardening, but may significantly increase the grain boundary phosphorus coverage and the likelihood of IGF.
Download or read book Effects of Radiation on Materials written by Arvind S. Kumar and published by ASTM International. This book was released on 1994 with total page 1319 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Survey of postirradiation heat treatment as a means to mitigate radiation embrittlement of reactor vessel steels written by J. R. Hawthorne and published by . This book was released on 1979 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Temper Embrittlement Irradiation Induced Phosphorus Segregation and Implications for Post Irradiation Annealing of Reactor Pressure Vessels written by CA. English and published by . This book was released on 1999 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: Three steels designated JPB, JPC and JPG from the IAEA Phase 3 Programme containing two copper and phosphorus levels were pre- and post-irradiation Charpy and hardness tested in the as-received (AR), 1200°C/0.5h heat treated (HT) and heat treated and 450°C/2000h aged (HTA) conditions. The HT condition, was designed to simulate coarse grained heat-affected zones (HAZ's) and showed a marked sensitivity to thermal ageing in all three alloys. Embrittlement after thermal ageing was greater in the higher phosphorus alloys JPB and JPG. Charpy shifts due to thermal ageing of between 118 and 209°C were observed and accompanied by pronounced intergranular fracture, due to phosphorus segregation. The irradiation embrittlement response was complex. The low copper alloys, JPC and JPB, in the HT and HTA condition exhibited significant irradiation induced Charpy shift but very low or even negative hardness changes indicating non-hardening embrittlement. The higher copper alloy, JPG, also exhibited irradiation hardening in line with its copper content. Fractographic and microchemical studies indicated irradiation induced phosphorus segregation and a transition from cleavage to intergranular failure at grain boundary phosphorus concentrations above a critical level. The enhanced grain boundary phosphorus level increased with dose in agreement with a kinetic segregation model developed at Harwell.
Download or read book Grain Boundary Phosphorus Segregation Under Irradiation and Thermal Aging and Its Effect on the Ductile to Brittle Transition written by S. Song and published by . This book was released on 2001 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Embrittlement of low-alloy steel components used in the nuclear power industry is classified into hardening embrittlement and non-hardening embrittlement. Hardening embrittlement stems from precipitation of carbides or copper-rich compounds. Non-hardening embrittlement results mainly from grain boundary segregation of phosphorus. To examine the non-hardening embrittlement in 2.25Cr 1Mo steel, phosphorus intergranular segregation in samples subjected to neutron irradiation and thermal aging at 270°C and 400°C is determined by modelling and transmission electron microscopy. The ductile-to-brittle transition temperature for the steel is determined by means of small punch testing with 3 mm diameter disc specimens. It is indicated that there is a reasonable agreement between the behavior of intergranular phosphorus segregation and shifts in the ductile-to-brittle transition temperature. Measured and predicted phosphorus intergranular segregation in a range of pressure vessel steels is also discussed.
Download or read book Radiation Damage of Nuclear Power Plant Pressure Vessel Steels written by Nikolaĭ Nikolaevich Alekseenko and published by . This book was released on 1997 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the current state of knowledge about pressure vessel material selection, fabrication (including welding), the changes in properties in service, and response to high-temperature annealing. In contrast to the bad reports of inadequate attention to reactor safety in the former Soviet Union, this book shows that the question of pressure vessel performance has received proper attention and a strong scientific base underlies the assessment of vessel life. This book should be read by reactor designers and operators and their scientific colleagues throughout the world.
Download or read book Irradiation Embrittlement of Reactor Pressure Vessel Steels written by GE. Lucas and published by . This book was released on 1986 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: A model of irradiation embrittlement is described for predicting the 41-J Charpy V-notch temperature shifts (?T) as a function of metallurgical variables and neutron exposure conditions. This forecasting procedure combines semi-empirical physical models with statistical analyses of test and power reactor data, and calibration against data from fundamental experiments in which both mechanical property and microstructural changes are evaluated. The models are based on the evolution of a damage microstructure, which includes both copper precipitates and a radiation damage component enhanced by nickel. The precipitate volume is also increased by nickel and impurity phosphorus. Predicted hardening and shifts associated with these extended defects are based on empirically validated models. The model is able to self-consistently rationalize a wide array of microstructural and mechanical property data for commercial pressure vessel steels as well as model alloys.
Download or read book Effects of Radiation on Materials written by D. S. Gelles and published by ASTM International. This book was released on 1996 with total page 1169 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigation of Temper Embrittlement in Reactor Pressure Vessel Steels Following Thermal Aging Irradiation and Thermal Annealing written by MA. Sokolov and published by . This book was released on 2001 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Heavy-Section Steel Irradiation Program at Oak Ridge National Laboratory includes a task to investigate the propensity for temper embrittlement in coarse grain regions of heat-affected zones in prototypic reactor pressure vessel (RPV) steel weldments as a consequence of irradiation and thermal annealing. For the present studies, five prototypic RPV steels with specifications of A302 grade B, A302 grade B (modified), A533 grade B class 1, and A508 class 2 were given two different austenitization treatments and various thermal aging treatments. Thermal aging treatments were conducted at 399, 425, 454 and 490°C for times of 168 and 2000 h. Charpy V-notch impact toughness vs temperature curves were developed for each condition with ductile-brittle transition temperatures used as the basis for comparing the effects of the various heat treatments. Very high austenitization heat treatment produced extremely large grains which exhibited a very high propensity for temper embrittlement following thermal aging. Intergranular fracture was the predominant mode of failure in many of the materials and Auger analysis confirmed significant segregation of phosphorus at the grain boundaries. Lower temperature austenitization treatment performed in a super Gleeble to simulate prototypic coarse grain microstructures in submerged-arc weldments produced the expected grain size with varying propensity for temper embrittlement dependent on the material as well as on the thermal aging temperature and time. Although the lower temperature treatment resulted in decreased propensity for temper embrittlement, the results did provide motivation for the investigation of the potential for phosphorus segregation as a consequence of neutron irradiation and post-irradiation thermal annealing at 454°C. One of the A 302 grade B (modified) steels was given the Gleeble treatment, irradiated at 288°C to about 0.8 x 1019n/cm (>1 MeV) and given a thermal annealing treatment at 454°C for 168 h. Charpy impact testing was conducted on the material in both the irradiated and irradiated/annealed conditions, as well as in the as-received condition. The results show that, although the material exhibited a relatively small Charpy impact 41-J temperature shift, the heat-affected zone-simulated material did exhibit significant intergranular fracture in the post-irradiation annealed condition.
Download or read book Effects of Radiation on Materials written by R. K. Nanstad and published by ASTM International. This book was released on 1999 with total page 1135 pages. Available in PDF, EPUB and Kindle. Book excerpt:
