Download or read book Final Results from the Crack Initiation and Arrest of Irradiated Steel Materials Project on Fracture Mechanical Assessments of Pre Irradiated RPV Steels Used in German PWR written by H. Hein and published by . This book was released on 2009 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pre-irradiated original reactor pressure vessel (RPV) materials covering all four German pressurized water reactors (PWR) construction lines were tested in the Crack Initiation and Arrest of Irradiated Steel Materials program to create a database of fracture toughness and arrest values for neutron fluences beyond the end of life range. The new database comprises data from both unirradiated and irradiated RPV base and weld materials generated by tensile, Charpy-V impact, fracture toughness KJc, and crack arrest KIa tests. The test matrix consists of materials with optimized chemical composition and with high Copper or high Nickel content, respectively. Based on the generated and already existing data the RTNDT and the RTT0 (Master Curve) concepts are applied with specific view on reference temperatures, transition temperature shifts, and on possible correlations between the criteria used in both concepts. In this context the consequences of some influencing factors like type and chemical composition of the RPV steel, its manufacturing conditions, and the specimen type and size on the reference temperatures are discussed. Moreover, the test results are assessed with respect to the American Society of Mechanical Engineers (ASME) code and German Nuclear Safety Standards Commission safety standards. The crack arrest characteristics for these typical RPV materials are also determined in a twofold way by testing Compact Crack Arrest specimens and by evaluation of instrumented Charpy-V impact test data. The available results made a good point that crack arrest is a reliable phenomenon that doubtless exists. It is also shown that the obtained KIa data can be enveloped by applying the ASME KIc lower bound curve indexed by different reference temperatures. Finally, the results show that the used RPV materials are well designed in terms of material behavior under irradiated conditions and that optimized manufacture specifications are of great benefit particularly after long operation times.
Download or read book Final Results from the CARINA Project on Crack Initiation and Arrest of Irradiated German RPV Steels for Neutron Fluences in the Upper Bound written by M. Widera and published by . This book was released on 2014 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Comprehensive crack initiation and crack arrest tests were performed, up to neutron fluences far beyond the end of life range, on irradiated original reactor pressure vessel (RPV) steel specimens from German pressurized water reactors (PWR). The neutron fluences applied to the specimen materials under light water reactor conditions were between 5.44 x 1018n/cm2 and 7.67 x 1019n/cm2 (E > 1 MeV) with a neutron flux from 2.64 x 1010n/cm2s to 2.55 x 1012n/cm2s. The objective was to extend the already existing experimental database to reach a final comparative assessment of both the RTNDT and the RTT0 (Master Curve) concepts for proof of sufficient margin against RPV brittle fracture and to assess the impact of important factors such as neutron flux, manufacturing effects and specific irradiation effects such as late blooming effects. The test data show that most of the measured fracture toughness data are enveloped by the "lower bound" ASME KIc-curve for crack initiation and that the RTT0 concept compared to the RTNDT concept leads to lower reference temperatures for the base materials. However, for the weld materials, the general trend of RTNDT > RTT0 is less or not at all pronounced. It was also found that the measured ?T41 and ?T0 data show a good correlation and that the RTT0 of heat affected zone (HAZ) materials is lower compared to the base materials. Finally, the applicability of both the RTNDT and the Master curve concepts for crack arrest was confirmed, except the alternative use of RTT0 for indexing of the KIa fracture toughness curve could not be confirmed by the measured data. The application of a so-called duplex specimen geometry for crack arrest testing led to essential improvements; however, further optimizations of the specimens' fabrication process are still recommended. Finally, the complete database is assessed with respect to benefits for future RPV safety analyses.
Download or read book Flaw Evaluation Service Experience and Materials for Hydrogen Service written by Yong-Yi Wang and published by . This book was released on 2004 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Brittle Fracture of Steel 1950 1961 written by and published by . This book was released on 1961 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: The bibliography has been compiled from the unclassified literature for the period January 1950 through November 15, 1961. Reviews and bibliographies which have been listed furnish references to historical reviews and earlier studies on brittle fracture. An author and a subject index are included.
Download or read book Specimen Size Considerations in Crack Arrest Testing of Irradiated RPV Steels written by MP. Landow and published by . This book was released on 1986 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Few crack-arrest data are available for irradiated reactor pressure vessel steels, in part because the specimens commonly used to investigate crack-arrest behavior are relatively large (200 mm square by 50 mm thick). This paper addresses the question of specimen-size requirements for crack-arrest testing of irradiated RPV steels and offers several recommendations with regard to specimen size, specimen design, and testing procedures for efficient utilization of the limited space available in irradiation capsules.
Download or read book Integrity of Reactor Pressure Vessels in Nuclear Power Plants written by and published by . This book was released on 2009 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication is intended to assist nuclear utilities in optimizing the service life of nuclear power plants. It reviews the latest research on the effects of neutron irradiation on the steels and welds of reactor pressure vessels within light water cooled and moderated reactors.
Download or read book Energy Research Abstracts written by and published by . This book was released on 1992 with total page 784 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Irradiated Dynamic and Arrest Fracture Toughness Compared to Lower Bound Predictions written by TR. Mager and published by . This book was released on 1992 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pressure-temperature operating curves for nuclear reactor pressure vessels are based upon a lower-bound fracture toughness curve which bounds rapid load dynamic initiation and crack arrest fracture toughness data. The ASME Boiler and Pressure Vessel Code defines the reference toughness (KIR) curve as this lower bound, and this KIR curve was developed solely from unirradiated dynamic and arrest fracture toughness data from one heat of SA533B-1 steel (HSST Plate 02) and two heats of SA508-2 steel. The effects of radiation embrittlement on the shape and shift of the KIR curve to account for the increase in reference temperature is thought to be conservative, but this conservatism has not been fully verified. This study reviews available data from past dynamic and arrest toughness tests on irradiated vessel steels from test reactor irradiations and compares the data to the shifted KIR curve using the transition temperature shift approach detailed in Regulatory Guide 1.99, Revision 2. Dynamic initiation and crack arrest fracture toughness data are available from only a few irradiated large specimen tests (that is, test specimens with thicknesses greater than about 51 mm [2 in.]); small specimen tests (including precracked Charpy) are used for the other comparisons. The limited results indicate that the Regulatory approach for shifting the KIR curve is very conservative even when the Regulatory Guide 1.99, Revision 2 "margin term" is not used and a correction for fluence rate is ignored. No change in shape for the dynamic toughness and arrest data (in particular for low upper shelf materials) was observed.
Download or read book Fracture Resistance of Irradiated Stainless Steel Clad Vessels written by Donald E. McCabe and published by . This book was released on 1990 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: A surface crack embedded in the clad layer of a reactor pressure vessel (RPV) has been identified as a critical safety assessment criterion in a pressurized thermal shock accident. This project was initiated to determine the severity of such cracks experimentally by using irradiated material, and to identify the material properties and stress conditions in the local region of the crack that are significant to the analysis. Bend bar tests provided an experimental simulation of the subject RPV surface crack. This report covers the analysis techniques used and presents the findings indicated by the experimental results for irradiated and unirradiated materials.
Download or read book Fracture Toughness and Impact Tests on Neutron Irradiated Ferritic Steels written by S. Chatterjee and published by . This book was released on 1994 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: Four A533B pressure vessel steels containing 0.16 wt% copper, nickel and phosphorous ranging from 0.10 to 0.82 wt% and 0.006 to 0.02 wt% respectively, and a AISI 403 stainless steel, a typical end fitting material used in pressurised heavy water reactors, in the unirradiated condition, were evaluated by instrumented impact testing to determine the crack initiation energy (CVNi), total absorbed energy (CVN), ductilebrittle transition temperature (T41J,T0.89mm), dynamic yield strength (?yd) and dynamic initiation fracture toughness (Kid). Three of these steels were irradiated at 563K to a nominal fast fluence of 1x1019, n/cm2 (E > 1 MeV) and the corresponding parameters were evaluated.
Download or read book Results of Crack arrest Tests on Irradiated A 508 Class 3 Steel written by S. K. Iskander and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book RESULTS OF CRACK ARREST TESTS ON IRRADIATED A 508 CLASS 3 STEEL NUREG CR 6447 U S NUCLEAR REGULATORY COMMISSION written by U.S. Nuclear Regulatory Commission and published by . This book was released on 1999* with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Results of Crack Arrest Tests on Irradiated A 508 Class 3 Steel written by S. K. Iskander and published by . This book was released on 1998-02-01 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book INIS Atomindex written by and published by . This book was released on 1988 with total page 860 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Crack Arrest Testing of Irradiated Nuclear Reactor Pressure Vessel Steels at the Oak Ridge National Laboratory written by SK. Iskander and published by . This book was released on 1998 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crack-arrest testing of nuclear pressure vessel steels has been conducted at Oak Ridge National Laboratory for many years. Four methods have been used to initiate fast-running cracks in crackarrest specimens: (1) the deposition of a brittle weld bead using hardfacing weld electrodes, (2) water quenching a chevron crack tip, (3) quenching the crack tip by discharging a large current into the crack tip region, and (4) the use of duplex specimens. A problem often encountered with Methods 1 and 4 is the control of the width of the heat-affected zone (HAZ). The HAZ is generally tough and can arrest crack propagation before it has run into the test section. Irradiated crack-arrest specimens were prepared using Methods 1, 3, and 4. Method 1 was the most successful, while Method 4 was the least successful. This paper will discuss some of the reasons for the success, or lack of, as well as the results of testing both a high-copper weldment and a low-copper forging in terms of the shift and shape of the Ka toughness curve compared to the Charpy V-notch shift. The present ASTM Test Method for Determining Plane-Strain Crack-Arrest Fracture Toughness, KIa, of Ferritic Steels (E 1221-88) validity criteria will also be discussed in light of the results.
Download or read book Acoustic Emission written by Zinoviy Nazarchuk and published by Springer. This book was released on 2017-01-23 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph analyses in detail the physical aspects of the elastic waves radiation during deformation or fracture of materials. It presents the methodological bases for the practical use of acoustic emission device, and describes the results of theoretical and experimental researches of evaluation of the crack growth resistance of materials, selection of the useful AE signals. The efficiency of this methodology is shown through the diagnostics of various-purpose industrial objects. The authors obtain results of experimental researches with the help of the new methods and facilities.
Download or read book Crack Arrest written by Lars Dahlberg and published by . This book was released on 1989 with total page 60 pages. Available in PDF, EPUB and Kindle. Book excerpt:
