Download or read book Constraint Effects on Fracture Toughness for Circumferentially Oriented Cracks in Reactor Pressure Vessels written by B. R. Bass 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 Constraint Effects in Fracture Theory and Applications written by Mark Kirk and published by ASTM International. This book was released on 1995 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analytical Studies of Transverse Strain Effects on Fracture Toughness for Circumferentially Oriented Cracks written by and published by . This book was released on 1991 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biaxial Loading Effects on Fracture Toughness of Reactor Pressure Vessel Steel written by and published by . This book was released on 1995 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Constraint Due to Out of Plane Stress Field on Fracture of Reactor Pressure Vessel Steel An Experimental and Numerical Study written by D. Detty and published by . This book was released on 1995 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent research on crack-tip constraint on fracture, including the effect of in-plane biaxial stress fields, has led to a two-parameter elastic K-T and elasto-plastic J-Q approach to correlate fracture toughness. These approaches predict a significant influence of biaxial stress state on fracture toughness. In the case of reactor pressure vessels undergoing pressurized thermal shock (PTS), significant stresses induced parallel to the crack front (out-of-plane stresses) offer additional constraint at the crack-tip. In order to evaluate the effect of this out-of-plane stress field on fracture of reactor pressure vessel steels, a unique method for testing a cruciform-type double-edge notch, DEN(T), specimen loaded in biaxial tension was developed. Three-dimensional finite-element analyses were conducted to design the specimen configuration. Details of the experimental and analytical results and the significance of the crack-tip constraint, due to biaxial stress state involving out-of-plane stresses, on the fracture toughness in the transition region are presented.
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Constraint on the Fracture Toughness of Reactor Pressure Vessel Steels written by Geena Kaur Rait and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analytical Modeling of the Effect of Crack Depth Specimen Size and Biaxial Stress on the Fracture Toughness of Reactor Vessel Steels written by and published by . This book was released on 1995 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fracture, toughness values for A533-B reactor pressure vessel (RPV) steel obtained from test programs at Oak Ridge National Laboratory (ORNL) and University of Kansas (KU) are interpreted using the J-A2 analytical model. The analytical model is based on the critical stress concept and takes into consideration the constraint effect using the second parameter A2 in addition to the generally accepted first parameter J which represents the loading level. It is demonstrated that with the constraint level included in the model effects of crack depth (shallow vs deep), specimen size (small vs. large), and loading type (uniaxial vs biaxial) on the fracture toughness from the test programs can be interpreted and predicted.
Download or read book Influence of Crack Depth on the Fracture Toughness of Reactor Pressure Vessel Steel written by JW. Bryson and published by . This book was released on 1993 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Heavy Section Steel Technology Program (HSST) at Oak Ridge National Laboratory (ORNL) is investigating the influence of flaw depth on the fracture toughness of reactor pressure vessel (RPV) steel. Recently, it has been shown that, in notched beam testing, shallow cracks tend to exhibit an elevated toughness as a result of a loss of constraint at the crack tip. The loss of constraint takes place when interaction occurs between the elastic-plastic crack-tip stress field and the specimen surface nearest the crack tip. An increased shallow-crack fracture toughness is of interest to the nuclear industry because probabilistic fracture-mechanics evaluations show that shallow flaws play a dominant role in the probability of vessel failure during postulated pressurized-thermal-shock (PTS) events.
Download or read book Monthly Catalogue United States Public Documents written by and published by . This book was released on 1994-04 with total page 980 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Crack Initiation Under Generalized Plane Strain Conditions written by and published by . This book was released on 1991 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: A method for estimating the decrease in crack-initiation toughness, from a reference plane strain value, due to positive straining along the crack front of a circumferential flaw in a reactor pressure vessel is presented in this study. This method relates crack initiation under generalized plane strain conditions with material failure at points within a distance of a few crack-tip-opening displacements ahead of a crack front, and involves the formulation of a micromechanical crack-initiation model. While this study is intended to address concerns regarding the effects of positive out-of- plane straining on ductile crack initiation, the approach adopted in this work can be extended in a straightforward fashion to examine conditions of macroscopic cleavage crack initiation. Provided single- parameter dominance of near-tip fields exists in the flawed structure, results from this study could be used to examine the appropriateness of applying plane strain fracture toughness to the evaluation of circumferential flaws, in particular to those in ring-forged vessels which have no longitudinal welds. In addition, results from this study could also be applied toward the analysis of the effects of thermal streaming on the fracture resistance of circumferentially oriented flaws in a pressure vessel. 37 refs., 8 figs., 1 tab.
Download or read book Fracture Mechanics written by Walter G. Reuter and published by ASTM International. This book was released on 1995 with total page 842 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Influence of Crack Depth on the Fracture Toughness of Reactor Pressure Vessel Steel written by and published by . This book was released on 1991 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Heavy Section Steel Technology Program (HSST) at Oak Ridge National Laboratory (ORNL) is investigating the influence of flaw depth on the fracture toughness of reactor pressure vessel (RPV) steel. Recently, it has been shown that, in notched beam testing, shallow cracks tend to exhibit an elevated toughness as a result of a loss of constraint at the crack tip. The loss of constraint takes place when interaction occurs between the elastic-plastic crack-tip stress field and the specimen surface nearest the crack tip. An increased shallow-crack fracture toughness is of interest to the nuclear industry because probabilistic fracture-mechanics evaluations show that shallow flaws play a dominant role in the probability of vessel failure during postulated pressurized-thermal-shock (PTS) events. Tests have been performed on beam specimens loaded in 3-point bending using unirradiated reactor pressure vessel material (A533 B). Testing has been conducted using specimens with a constant beam depth (W = 94 mm) and within the lower transition region of the toughness curve for A533 B. Test results indicate a significantly higher fracture toughness associated with the shallow flaw specimens compared to the fracture toughness determined using deep-crack (a/W = 0.5) specimens. Test data also show little influence of thickness on the fracture toughness for the current test temperature ( -60°C). 21 refs., 5 figs., 3 tabs.
Download or read book Crack Initiation Under Generalized Plane Strain Conditions written by JG. Merkle and published by . This book was released on 1993 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: A method for estimating the decrease in crack-initiation toughness, from a reference plane-strain value, due to positive straining along the crack front of a circumferential flaw in a reactor pressure vessel, is presented in this study. This method relates crack initiation under generalized plane-strain conditions with material failure at points within a distance of a few crack-tip-opening displacements ahead of a crack front, and involves the formulation of a micro-mechanical crack-initiation model. While this study is intended to address concerns regarding the effects of positive out-of-plane straining on ductile crack initiation, the approach adopted in this work can be extended in a straightforward fashion to examine conditions of macroscopic cleavage crack initiation. Provided single-parameter dominance of near-tip fields exists in the flawed structure, results from this study could be used to examine the appropriateness of applying plane-strain fracture toughness to the evaluation of circumferential flaws, in particular to those in ring-forged vessels that have no longitudinal welds. In addition, results from this study could also be applied toward the analysis of the effects of thermal streaming on the fracture resistance of circumferentially oriented flaws in a pressure vessel.
Download or read book Fatigue and Fracture Mechanices written by Steven R. Daniewicz and published by ASTM International. This book was released on 2005-09 with total page 591 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Energy Research Abstracts written by and published by . This book was released on 1994-02 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fracture Mechanics of Through cracked Cylindrical Pressure Vessels written by Robert B. Anderson and published by . This book was released on 1966 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: The application of some fracture mechanics concepts to the prediction of the strength of pressure vessels in which cracks have penetrated entirely through the vessel wall is examined. The strength of cylindrical pressure vessels (with longitudinal through-cracks) is related to the geometry of the cylinder, the crack length, the material yield strength, and fracture toughness. An expression for the crack tip stress intensity factor is derived by considering the influence on the stress near the crack tip of membrane stressing in the cylinder and of bending caused by bulging of the partially constrained material on either side of the crack. The form of the derived expression is verified and empirical constants evaluated from burst data at -320 and -423 F of aluminum alloy (2014-T6 A1) and extra-low-interstitial (ELI) titanium alloy (5A1-2. 5Sn-Ti) The analysis, basdd on the Irwin fracture theory, provides a suitable means for the correlation of the strength of flat-sheet specimens with that of cracked pressurized cylinders. The correlation suggests that the fracture strength of through-cracked cylinders of any radius, crack length, and thickness can be determined from material toughness, yield strength, and a bulge coefficient. Neglect of the effect of pressure bulging in the fracture analysis of pressurized cylinders can cause a significant overestimate of the fracture strength.
