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Environmentally Assisted Cracking in Light Water Reactors - Annual Report, January-December 2001.

Description: This report summarizes work performed by Argonne National Laboratory on fatigue and environmentally assisted cracking (EAC) in light water reactors (LWRs) from January to December 2001. Topics that have been investigated include (a) environmental effects on fatigue S-N behavior of austenitic stainless steels (SSs), (b) irradiation-assisted stress corrosion cracking (IASCC) of austenitic SSs, and (c) EAC of Alloy 600. The effects of key material and loading variables, such as strain amplitude, s… more
Date: June 1, 2003
Creator: Chopra, O. K.; Chung, H. M.; Clark, R. W.; Gruber, E. E; Hiller, R. W.; Shack, W. J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Use of composite materials, health monitoring and self-healing concepts to refurbish our civil and military infrastructure.

Description: An unavoidable by-product of a metallic structure's use is the appearance of crack, corrosion, erosion and other flaws. Economic barriers to the replacement of these structures have created an aging civil and military infrastructure and placed even greater demands on efficient and safe repair and inspection methods. As a result of Homeland Security issues and these aging infrastructure concerns, increased attention has been focused on the rapid repair and preemptive reinforcement of structures … more
Date: September 1, 2007
Creator: Roach, Dennis Patrick; Delong, Waylon Anthony; White, Scott (University of Illinois, Urbana, Illinois); Yepez, Esteban; Rackow, Kirk A. & Reedy, Earl David, Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A STRUCTURAL IMPACT ASSESSMENT OF FLAWS DETECTED DURING ULTRASONIC EXAMINATION OF TANK 15

Description: Ultrasonic (UT) inspection of Tank 15 was conducted between April and July 2007 in accordance with the Tank 15 UT inspection plan. This was a planned re-inspection of this tank, the previous one was performed in 2002. Ten cracks were characterized in the previous examination. The re-inspection was performed to verify the present models and understanding for stress corrosion cracking. During this re-examination, one indication that was initially reported as a 'possible perpendicular crack <25… more
Date: August 21, 2008
Creator: Wiersma, B & James Elder, J
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Multiple-code simulation study of the long-term EDZ evolution of geological nuclear waste repositories

Description: This simulation study shows how widely different model approaches can be adapted to model the evolution of the excavation disturbed zone (EDZ) around a heated nuclear waste emplacement drift in fractured rock. The study includes modeling of coupled thermal-hydrological-mechanical (THM) processes, with simplified consideration of chemical coupling in terms of time-dependent strength degradation or subcritical crack growth. The different model approaches applied in this study include boundary ele… more
Date: October 23, 2008
Creator: Rutqvist, J.; Backstrom, A.; Chijimatsu, M.; Feng, X. T.; Pan, P. Z.; Hudson, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Stress Corrosion Cracking Response of 304 Stainless Steel in ASerated and Dearated Water

Description: Scoping stress corrosion cracking (SCC) tests of 304 stainless steel (SS) were performed in 75 C and 250 C aerated pressurized water (APW) and 250 C deaerated pressurized water (DPW). The 250 C APW environment was used to initiate intergranular stress corrosion cracking (IGSCC) and then the water was deaerated and hydrogenated to see if IGSCC continued in 250 C DPW. Tests were performed with and without 200 ppb SO{sub 4}{sup =}. The 304 SS test materials were evaluated in either the as-received… more
Date: April 30, 2007
Creator: Mills, W. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Environmentally Assisted Cracking in Light Water Reactors : Semiannual Report, July 2000 - December 2000.

Description: This report summarizes work performed by Argonne National Laboratory on fatigue and environmentally assisted cracking (EAC) in light water reactors (LWRs) from July 2000 to December 2000. Topics that have been investigated include (a) environmental effects on fatigue S-N behavior of primary pressure boundary materials, (b) irradiation-assisted stress corrosion cracking (IASCC) of austenitic stainless steels (SSs), and (c) EAC of Alloys 600 and 690. The fatigue strain-vs.-life data are summarize… more
Date: April 1, 2002
Creator: Chopra, O. K.; Chung, H. M.; Gruber, E. E.; Shack, W. J.; Soppet, W. K.; Strain, R. V. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Rolling Contact Fatigue of Ceramics

Description: High hardness, low coefficient of thermal expansion and high temperature capability are properties also suited to rolling element materials. Silicon nitride (Si{sub 3}N{sub 4}) has been found to have a good combination of properties suitable for these applications. However, much is still not known about rolling contact fatigue (RCF) behavior, which is fundamental information to assess the lifetime of the material. Additionally, there are several test techniques that are employed internationally… more
Date: September 1, 2006
Creator: Wereszczak, Andrew A.; Wang, W.; Wang, Y.; Hadfield, M.; Kanematsu, W.; Kirkland, Timothy Philip et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies on the disbonding initiation of interfacial cracks.

Description: With the continuing trend of decreasing feature sizes in flip-chip assemblies, the reliability tolerance to interfacial flaws is also decreasing. Small-scale disbonds will become more of a concern, pointing to the need for a better understanding of the initiation stage of interfacial delamination. With most accepted adhesion metric methodologies tailored to predict failure under the prior existence of a disbond, the study of the initiation phenomenon is open to development and standardization o… more
Date: August 1, 2005
Creator: McAdams, Brian J. (Lehigh University, Bethlehem, PA) & Pearson, Raymond A. (Lehigh University, Bethlehem, PA)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Simulating the pervasive fracture and fragmentation of materials and structures using randomly close-packed Voronoi tessellations.

Description: Under extreme loading conditions most often the extent of material and structural fracture is pervasive in the sense that a multitude of cracks are nucleating, propagating in arbitrary directions, coalescing, and branching. Pervasive fracture is a highly nonlinear process involving complex material constitutive behavior, material softening, localization, surface generation, and ubiquitous contact. Two primary applications in which pervasive fracture is encountered are (1) weapons effects on str… more
Date: September 1, 2008
Creator: Bishop, Joseph E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mitigation of Laser Damage Growth in Fused Silica with a Galvanometer Scanned CO2 Laser

Description: At the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL), mitigation of laser surface damage growth on fused silica using single and multiple CO{sub 2} laser pulses has been consistently successful for damage sites whose lateral dimensions are less than 100 {micro}m, but has not been for larger sites. Cracks would often radiate outward from the damage when a CO{sub 2} pulse was applied to the larger sites. An investigation was conducted to mitigate large surf… more
Date: October 28, 2005
Creator: Bass, I L; Guss, G M & Hackel, R P
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Increasing Safety and Reducing Environmental Damage Risk from Aging High-Level Radioactive Waste Tanks

Description: Cracks of various shapes and sizes exist in large high-level waste (HLW) tanks at several DOE sites. There is justifiable concern that these cracks could grow to become unstable causing a substantial release of liquid contaminants to the environment. Accurate prediction of crack growth behavior in the tanks, especially during accident scenarios, is not possible with existing analysis methodologies. This research project responds to this problem by developing an improved ability to predict crack… more
Date: June 1, 2005
Creator: Steffler, Eric D.; McClintock, Frank A.; Lloyd, W. Randolph; Rashid, Mark M. & Williamson, Richard L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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FRACTURE BEHAVIOR OF ALLOY 600, ALLOY 690, EN82H WELDS AND EN52 WELDS IN WATER

Description: The cracking resistance of Alloy 600, Alloy 690 and their welds, EN82H and EN52, was characterized by conducting J{sub IC} rising load tests in air and hydrogenated water and cooldown testing in water under constant-displacement conditions. All test materials displayed excellent toughness in air and high temperature water, but Alloy 690 and the two welds were severely embrittled in low temperature water. In 54 C water with 150 cc H{sub 2}/kg H{sub 2}O, J{sub IC} values were reduced by 70% to 95… more
Date: January 11, 2000
Creator: Mills, W.J., Brown, C.M. and Burke, M.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Crack growth rates and fracture toughness of irradiated austenitic stainless steels in BWR environments.

Description: In light water reactors, austenitic stainless steels (SSs) are used extensively as structural alloys in reactor core internal components because of their high strength, ductility, and fracture toughness. However, exposure to high levels of neutron irradiation for extended periods degrades the fracture properties of these steels by changing the material microstructure (e.g., radiation hardening) and microchemistry (e.g., radiation-induced segregation). Experimental data are presented on the frac… more
Date: January 21, 2008
Creator: Chopra, O. K. & Shack, W. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A micromechanical basis for partitioning the evolution of grainbridging in brittle materials

Description: A micromechanical model is developed for grain bridging inmonolithic ceramics. Specifically, bridge formation of a single,non-equiaxed grain spanning adjacent grains is addressed. A cohesive zoneframework enables crack initiation and propagation along grainboundaries. The evolution of the bridge is investigated through avariance in both grain angle and aspect ratio. We propose that thebridging process can be partitioned into five distinct regimes ofresistance: propagate, kink, arrest, stall, an… more
Date: October 9, 2006
Creator: Foulk, J. W., III; Cannon, R. M.; Johnson, G. C.; Klein, P. A. & Ritchie, R. O.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Oxygen Transport Ceramic Membranes

Description: In the present quarter, experiments are presented on ceramic/metal interactions of Zirconia/ Ni-B-Si system and with a thin Ti coating deposited on zirconia surface. Existing facilities were modified for evaluation of environmental assisted slow crack growth and creep in flexural mode. Processing of perovskites of LSC, LSF and LSCF composition were continued for evaluation of mechanical properties as a function of environment. These studies in parallel to those on the LSFCO composition is expec… more
Date: August 7, 2003
Creator: Bandopadhyay, S. & Nagabhushana, N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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In-situ Fracture Studies and Modeling of the Toughening Mechanism Present in Wrought LCAC, TZM, and ODS Molybdenum Flat Products

Description: In-situ testing, ultrasonic C-scans, and metallography were used to show that a crack-divider delamination form of thin-sheet toughening occurs in wrought Low Carbon Arc Cast (LCAC) unalloyed molybdenum, Oxide Dispersion Strengthened (ODS) molybdenum, and TZM molybdenum at temperatures {ge} the Ductile to Brittle Transition Temperature (DBTT). Cracking along boundaries relieves mechanical constraint to free ligaments that may plastically stretch to produce toughening. Anisotropy in fracture tou… more
Date: July 1, 2007
Creator: Cockerman, B. V. and Chan, K. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effects of Alloy Chemistry, Cold Work, and Water Chemistry on Corrosion Fatigue and Stress Corrosion Cracking of Nickel Alloys and Welds.

Description: Reactor vessel internal components made of nickel-base alloys are susceptible to environmentally assisted cracking (EAC). A better understanding of the causes and mechanisms of this cracking may permit less conservative estimates of damage accumulation and requirements on inspection intervals. The objective of this work is to evaluate and compare the resistance of Alloys 600 and 690 and their welds, such as Alloys 82, 182, 52, and 152, to EAC in simulated light water reactor environments. The e… more
Date: April 1, 2001
Creator: Chopra, O. K.; Soppet, W. K.; Shack, W. J. & Technology, Energy
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Environmentally Assisted Cracking in Light Water Reactors Annual Report January - December 2005.A

Description: This report summarizes work performed from January to December 2005 by Argonne National Laboratory on fatigue and environmentally assisted cracking in light water reactors (LWRs). Existing statistical models for estimating the fatigue life of carbon and low-alloy steels and austenitic stainless steels (SSs) as a function of material, loading, and environmental conditions were updated. Also, the ASME Code fatigue adjustment factors of 2 on stress and 20 on life were critically reviewed to assess… more
Date: August 31, 2007
Creator: Alexandreanu, B.; Chen, Y.; Chopra, O. K.; Chung, H. M.; Gruber, E. E.; Shack, W. J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Crack growth rates and metallographic examinations of Alloy 600 and Alloy 82/182 from field components and laboratory materials tested in PWR environments.

Description: In light water reactors, components made of nickel-base alloys are susceptible to environmentally assisted cracking. This report summarizes the crack growth rate results and related metallography for field and laboratory-procured Alloy 600 and its weld alloys tested in pressurized water reactor (PWR) environments. The report also presents crack growth rate (CGR) results for a shielded-metal-arc weld of Alloy 182 in a simulated PWR environment as a function of temperature between 290 C and 350 C… more
Date: May 5, 2008
Creator: Alexandreanu, B.; Chopra, O. K. & Shack, W. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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EXPERT PANEL OVERSIGHT COMMITTEE ASSESSMENT OF FY2008 CORROSION AND STRESS CORROSION CRACKING SIMULANT TESTING PROGRAM

Description: The Expert Panel Oversight Committee (EPOC) has been overseeing the implementation of selected parts of Recommendation III of the final report, Expert Panel workshop for Hanford Site Double-Shell Tank Waste Chemistry Optimization, RPP-RPT-22126. Recommendation III provided four specific requirements necessary for Panel approval of a proposal to revise the chemistry control limits for the Double-Shell Tanks (DSTs). One of the more significant requirements was successful performance of an acceler… more
Date: January 8, 2009
Creator: KD, BOOMER
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Simulations of dynamic crack propagation in brittle materials using nodal cohesive forces and continuum damage mechanics in the distinct element code LDEC

Description: Experimental data indicates that the limiting crack speed in brittle materials is less than the Rayleigh wave speed. One reason for this is that dynamic instabilities produce surface roughness and microcracks that branch from the main crack. These processes increase dissipation near the crack tip over a range of crack speeds. When the scale of observation (or mesh resolution) becomes much larger than the typical sizes of these features, effective-medium theories are required to predict the coar… more
Date: August 23, 2006
Creator: Block, G I; Rubin, M B; Morris, J P & Berryman, J G
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Crack growth rates of irradiated austenitic stainless steel weld heat affected zone in BWR environments.

Description: Austenitic stainless steels (SSs) are used extensively as structural alloys in the internal components of reactor pressure vessels because of their superior fracture toughness. However, exposure to high levels of neutron irradiation for extended periods can exacerbate the corrosion fatigue and stress corrosion cracking (SCC) behavior of these steels by affecting the material microchemistry, material microstructure, and water chemistry. Experimental data are presented on crack growth rates of th… more
Date: January 31, 2006
Creator: Chopra, O. K.; Alexandreanu, B.; Gruber, E. E.; Daum, R. S.; Shack, W. J. & Technology, Energy
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Application of Reliability-Based Design Factors In Stress Corrosion Cracking Evaluations

Description: First-order reliability methodology (FORM) is used to develop reliability-based design factors for deterministic analyses of stress corrosion cracking. The basic elements of FORM as applied to structural reliability problems are reviewed and then employed specifically to stress corrosion cracking evaluations. Failure due to stress corrosion cracking is defined as crack initiation followed by crack growth to a critical depth. The stress corrosion cracking process is thus represented in terms of … more
Date: December 20, 2001
Creator: Friedman, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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EFFECTS OF CHEMISTRY AND OTHER VARIABLES ON CORROSION AND STRESS CORROSION CRACKING IN HANFORD DOUBLE SHELL TANKS

Description: Laboratory testing was performed to develop a comprehensive understanding of the corrosivity of the tank wastes stored in Double-Shell Tanks using simulants primarily from Tanks 241-AP-105, 241-SY-103 and 241-AW-105. Additional tests were conducted using simulants of the waste stored in 241-AZ-102, 241-SY-101, 241-AN-107, and 241-AY-101. This test program placed particular emphasis on defining the range of tank waste chemistries that do not induce the onset of localized forms of corrosion, part… more
Date: November 13, 2008
Creator: MH, BROWN
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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