Download or read book Radiation and Thermally Induced Phosphorus Inter Granular Segregation in Pressure Vessel Steels written by Z. Lu and published by . This book was released on 2005 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: A survey of neutron- and thermally-induced phosphorus inter-granular segregation behavior in C-Mn welds, LWR plates, LWR HAZ materials, and VVER steels is described in this paper. The materials were irradiated up to doses of 0.13 dpa (fast neutron energy > 1 MeV), with dose rates ranging from 1.75 × 10−8 dpa/s to 10−12 dpa/s, at temperatures between 190°C and 400°C. Irradiation-induced P inter-granular segregation has been found in LWR and VVER materials at high doses (generally 10-130 mdpa) but is absent in all Magnox C-Mn submerged-arc welds at lower doses (1.5-13 mdpa). The dose sensitivity of the irradiation-induced P monolayer coverage depends on the material examined, being highest for VVER plates and weld, lower for the LWR materials, and zero for the C-Mn welds. There are high initial P segregations (arising from pre-heat-treatment) in C-Mn weld and LWR HAZ materials and low initial P segregation in LWR and VVER steels. Comparisons of the experimental data with model predictions are made. The amount of phosphorus segregation is shown via site competition models to be related to free carbon concentration. The model results show a good agreement with experimental measurements.

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 Radiation on Materials written by Todd R. Allen and published by ASTM International. This book was released on 2006 with total page 411 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Irradiation Embrittlement of Reactor Pressure Vessels RPVs in Nuclear Power Plants written by Naoki Soneda and published by Elsevier. This book was released on 2014-09-01 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reactor Pressure Vessels (RPVs) contain the fuel and therefore the reaction at the heart of nuclear power plants. They are a life-determining structural component: if they suffer serious damage, the continued operation of the plant is in jeopardy. This book critically reviews irradiation embrittlement, the main degradation mechanism affecting RPV steels, and mitigation routes for managing the RPV lifetime. Part I reviews RPV design and fabrication in different countries, with an emphasis on the materials required, their important properties, and manufacturing technologies. Part II then considers RVP embrittlement in operational nuclear power plants using different reactors. Chapters are devoted to embrittlement in light-water reactors, including WWER-type reactors and Magnox reactors. Finally, Part III presents techniques for studying embrittlement, including irradiation simulation techniques, microstructural characterisation techniques, and probabilistic fracture mechanics. Irradiation Embrittlement of Reactor Pressure Vessels (RPVs) in Nuclear Power Plants provides a thorough review of an issue that is central to the safety of nuclear power generation. The book includes contributions from an international team of experts, and will be a useful resource for nuclear plant operators and managers, relevant regulatory and safety bodies, nuclear metallurgists and other academics in this field - Discusses reactor pressure vessel (RPV) design and the effect irradiation embrittlement can have, the main degradation mechanism affecting RPVs - Examines embrittlement processes in RPVs in different reactor types, as well as techniques for studying RPV embrittlement

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 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 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:

Download or read book Radiation Induced Grain Boundary Segregation of Phosphorus in ASME SA533B Ferritic Pressure Vessel Steel written by D. Meade and published by . This book was released on 2000 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: The segregation of phosphorus to grain boundaries is well known to cause embrittlement in a range of ferritic pressure vessel steels. Modelling of segregation is therefore useful in predicting the service life of pressure vessels, particularly in those pressure vessels used in nuclear reactor power generating plant where significant cost savings can be made. In this paper, predictions of the radiation induced grain boundary segregation of phosphorus in ASME SA533B pressure vessel steels are made using an analytical model for impurity segregation in dilute ternary alloys. The model takes into account equilibrium-type segregation, together with a newly adopted approach incorporating the site competition effects that exist between phosphorus and carbon. The site competition effect causes the predicted phosphorus segregation to fall to levels significantly lower than the predictions obtained from models of dilute binary alloys. The predictions are compared to FEGSTEM results of samples irradiated at between 255°C and 315°C, doses between 1.5 and 38mdpa and dose rates ranging from 6x10-9 to 8.9x10-11 dpa/s. The predictions obtained from the model are in close agreement to the experimentally observed segregated phosphorus results.

Download or read book The Modeling of Radiation Induced Phosphorus Segregation at Point Defect Sinks in Dilute Fe P Alloys written by IA. Stepanov and published by . This book was released on 2004 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Both the intergranular and intragranular segregation of phosphorus may significantly contribute to irradiation embrittlement of reactor pressure vessel steels. The modeling of phosphorus radiation-induced segregation at cylindrical (dislocations), spherical (precipitates and voids) and flat (sample surfaces, grain boundaries) point defect sinks has been carried out in order to compare the kinetics and extent of segregation at various point defect sinks. Dilute Fe-P alloys relevant to model and VVER-440 pressure vessel steels were considered.

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 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 Review of Phosphorus Segregation and Intergranular Embrittlement in Reactor Pressure Vessel Steels PWRMRP 19 written by S. Rosinski and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Radiation on Materials written by Stan T. Rosinski and published by ASTM International. This book was released on 2001 with total page 879 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Modelling of Irradiation Enhanced Phosphorus Segregation in Neutron Irradiated Reactor Pressure Vessel Submerged Arc Welds written by CJ. Bolton and published by . This book was released on 1996 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent results on neutron-irradiated RPV submerged-arc welds have revealed grain boundary segregation of phosphorus during irradiation, which may lead to intergranular fracture. However, the experimental database is insufficient to define the dependence of the process on variables such as dose, dose-rate and temperature. This paper describes work in which two existing models of phosphorus segregation, under thermal or irradiation conditions, have been developed to obtain predictions of these dependencies.

Download or read book Effects of Radiation on Materials written by N. H. Packan and published by ASTM International. This book was released on 1990 with total page 679 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation Effects of Radiation on Materials: Fourteenth International Symposium was presented at Andover, MA, June 1988. The symposium was sponsored by ASTM Committee E-10 on Nuclear Technology and Applications. The papers from the first three days of the symposium appear in the two volumes of this publication. Volume I encompasses radiation damage- induced microstructures; point defect, solute, and gas atom effects; atomic-level measurement techniques; and applications of theory. Volume II includes mechanical behavior, all papers dealing with pressure-vessel steels, breeder reactor components, dosimetry, and nuclear fuels. The fourth day of the symposium was devoted to the single topic of reduced-activation materials (see TK9204). The two volumes are separately sold at $127 and $128 respectively; each is independently indexed. Annotation copyrighted by Book News, Inc., Portland, OR.

Download or read book Nuclear Materials under Irradiation written by Serge Bouffard and published by John Wiley & Sons. This book was released on 2024-01-11 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: At every stage of the fuel cycle, the materials used are at the heart of nuclear energy safety issues. These materials, which range from steel to polymers, including ceramics, glass, concrete and graphite, are submitted to extreme stresses combining mechanical, thermal and irradiation constraints. The objective of this book is to provide a basis for the research of nuclear materials subjected to irradiation, with the desire to contextualize them in the industrial environment. Therefore, most of the chapters are co-authored and contain a mix of basic and applied research. The reader will find chapters on nuclear reactor materials (structural materials, neutron absorbers, moderators and nuclear fuel) and on materials in waste management (glass, concrete and organic materials). These material chapters are complemented by more general information on defects and their creation, radiolysis and irradiation and characterization tools.

Download or read book Comprehensive Structural Integrity written by Ian Milne and published by Elsevier. This book was released on 2003-07-25 with total page 4647 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this major reference work is to provide a first point of entry to the literature for the researchers in any field relating to structural integrity in the form of a definitive research/reference tool which links the various sub-disciplines that comprise the whole of structural integrity. Special emphasis will be given to the interaction between mechanics and materials and structural integrity applications. Because of the interdisciplinary and applied nature of the work, it will be of interest to mechanical engineers and materials scientists from both academic and industrial backgrounds including bioengineering, interface engineering and nanotechnology. The scope of this work encompasses, but is not restricted to: fracture mechanics, fatigue, creep, materials, dynamics, environmental degradation, numerical methods, failure mechanisms and damage mechanics, interfacial fracture and nano-technology, structural analysis, surface behaviour and heart valves. The structures under consideration include: pressure vessels and piping, off-shore structures, gas installations and pipelines, chemical plants, aircraft, railways, bridges, plates and shells, electronic circuits, interfaces, nanotechnology, artificial organs, biomaterial prostheses, cast structures, mining... and more. Case studies will form an integral part of the work.