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Comparison of the Relative Importance of Helium and Vacancy Accumulation in Void Nucleation

Description: Void nucleation in irradiated austenitic stainless steels generally requires the presence of either residual or transmutant gases. Classical nucleation rates are much too low to account for the number of voids observed at temperatures greater than about 450/sup 0/C. An alternate path is generally believed to be responsible for void formation; viz. the growth of gas-stabilized bubbles until they reach a critical size beyond which further gas accumulation is not required to promote growth. Two li… more
Date: June 1, 1986
Creator: Stoller, R. E. & Odette, G. R.
Partner: UNT Libraries Government Documents Department
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Test methods for selection of materials of construction for high-level radioactive waste vitrification. Revision

Description: Candidate materials of construction were evaluated for a facility at the Department of Energy's Savannah River Plant to vitrify high-level radioactive waste. Limited operating experience was available under the corrosive conditions of the complex vitrification process. The objective of the testing program was to provide a high degree of assurance that equipment will meet or exceed design lifetimes. To meet this objective in reasonable time and minimum cost, a program was designed consistin… more
Date: January 1, 1986
Creator: Bickford, D F; Corbett, R A & Morrison, W S
Partner: UNT Libraries Government Documents Department
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Composite Model of Microstructural Evolution in Austenitic Stainless Steel Under Fast Neutron Irradiation

Description: A rate-theory-based model has been developed which includes the simultaneous evolution of the dislocation and cavity components of the microstructure of irradiated austenitic stainless steels. Previous work has generally focused on developing models for void swelling while neglecting the time dependence of the dislocation structure. These models have broadened our understanding of the physical processes that give rise to swelling, e.g., the role of helium and void formation from critically-size… more
Date: January 1, 1986
Creator: Stoller, R. E. & Odette, G. R.
Partner: UNT Libraries Government Documents Department
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Void-precipitate association during neutron irradiation of austenitic stainless steel

Description: Microstructural data has recently become available on a single heat of 316 stainless steel irradiated in EBR-II and HFIR, over a wide range of irradiation temperature (55 to 750/sup 0/C), dose (7 to 75 dpa), and helium generation rate (0.5 to 55 at. ppM He/dpa). Extensive information on precipitate compositions and characteristics are included. The data reveal several important relationships between the development of voids and precipitation. Precipitate associated voids dominate the swelling o… more
Date: January 1, 1986
Creator: Pedraza, D. F. & Maziasz, P. J.
Partner: UNT Libraries Government Documents Department
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Materials surface modification by plasma bombardment under simultaneous erosion and redeposition conditions

Description: The first in-depth investigation of surface modification of materials by continuous, high-flux argon plasma bombardment under simultaneous erosion and redeposition conditions have been carried out for copper and 304 stainless steel using the PISCES facility. The plasma bombardment conditions are: incident ion flux range from 10/sup 17/ to 10/sup 19/ ions sec/sup -1/cm/sup -2/, total ion fluence is controlled between 10/sup 19/ and 10/sup 22/ ions cm/sup -2/, electron temperature range from 5 to… more
Date: July 1, 1986
Creator: Hirooka, Y.; Goebel, D. M.; Conn, R. W.; Campbell, G. A.; Leung, W. K.; Wilson, K. L. et al.
Partner: UNT Libraries Government Documents Department
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Status of ANL out-of-pile investigations of severe accident phenomena for liquid metal reactors

Description: Research addressing LMFBR whole core accidents has been terminated, and there is now emphasis on quantifying reactivity feedbacks, and in particular enhancing negative feedback, so that advanced LMR designs will provide inherently safe operation. The status of recent HCDA-related laboratory research performed at ANL, up to the time that such activities were no longer needed to support CRBR licensing, is described. Included are descriptions of programs addressing sodium channel voiding, fuel swe… more
Date: January 1, 1986
Creator: Spencer, B. W.; Marchaterre, J. F.; Anderson, R. P.; Armstrong, D. R.; Baker, L.; Cho, D. H. et al.
Partner: UNT Libraries Government Documents Department
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Technical report on material selection and processing guidelines for BWR coolant pressure boundary piping. Draft report. Revision 2

Description: This report updates and supersedes the technical positions NRC established in NUREG-0313, ''Technical Report on Material Selection and Processing Guidelines for BWR Coolant Pressure Boundary Piping,'' published in July 1977, and its subsequent revision published in July 1980. This report sets forth the NRC staff's revised acceptable methods to control the intergranular stress corrosion cracking susceptibility of BWR ASME Code Class 1, 2, and 3 pressure boundary piping and safe ends. For piping … more
Date: June 1, 1986
Creator: Hazelton, W.S.
Partner: UNT Libraries Government Documents Department
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Infrared Sensing Techniques for Adaptive Robotic Welding

Description: The objective of this research is to investigate the feasibility of using infrared sensors to monitor the welding process. Data were gathered using an infrared camera which was trained on the molten metal pool during the welding operation. Several types of process perturbations which result in weld defects were then intentionally induced and the resulting thermal images monitored. Gas tungsten arc using ac and dc currents and gas metal arc welding processes were investigated using steel, alumin… more
Date: January 1, 1986
Creator: Lin, T. T.; Groom, K.; Madsen, N. H. & Chin, B. A.
Partner: UNT Libraries Government Documents Department
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Attenuation of shock waves in copper and stainless steel

Description: By using shock pins, data were gathered on the trajectories of shock waves in stainless steel (SS-304L) and oxygen-free-high-conductivity copper (OFHC-Cu). Shock pressures were generated in these materials by impacting the appropriate target with thin (approx.1.5 mm) flying plates. The flying plates in these experiments were accelerated to high velocities (approx.4 km/s) by high explosives. Six experiments were conducted, three using SS-304L as the target material and three experiments using OF… more
Date: June 1, 1986
Creator: Harvey, W.B.
Partner: UNT Libraries Government Documents Department
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Cross Section Evaluation Working Group benchmark specifications. Volume 2. Supplement

Description: Neutron and photon flux spectra have been measured and calculated for the case of neutrons produced by D-T reactions streaming through a cylindrical iron duct surrounded by concrete. Measurements and calculations have also been obtained when the iron duct is partially filled by a laminated stainless steel and borated polyethylene shadow bar. Schematic diagrams of the experimental apparatus is included.
Date: September 1, 1986
Partner: UNT Libraries Government Documents Department
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Initiation of stress corrosion cracking of sensitized type 304 stainless steel

Description: The corrosion potential of stressed sensitized Type 304 stainless steels were studied in oxygen-containing solutions to determine the relation between potential fluctuations and the initiation of stress-corrosion cracking. An in situ scanning vibrating electrode technique was shown to detect currents coming from growing stress corrosion cracks in dilute thiosulfate solutions at temperatures below 90/sup 0/C. The onset of the cracking was clearly indicted by rapid decreases in the potential. It … more
Date: January 1, 1986
Creator: Isaacs, H. S.
Partner: UNT Libraries Government Documents Department
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Tritium permeation in passivated 304L stainless steels

Description: Tritium permeation is controlled by surface permeation (e.g., cleaning, Pd coating). Tritium at the surface is disassociated. Various 304-L ss after various treatments were characterized, and tritium permeation studies were carried out at Los Alamos. Results were used to order the passivation treatments with regard to permeation resistance.
Date: January 1, 1986
Creator: Rising, T.L.
Partner: UNT Libraries Government Documents Department
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Materials erosion and redeposition studies at the PISCES-facility: net erosion under redeposition

Description: Simultaneous erosion and redeposition of copper and 304 stainless steel under controlled and continuous plasma (D,He,Ar) bombardment has been investigated in the PISCES-facility, which generates typical edge-plasma conditions of magnetic fusion devices. The plasma bombardment conditions are: incident ion flux in the range from 10/sup 17/ to 10/sup 18/ ions/sec/cm/sup 2/, ion bombarding energy of 100 eV, electron temperature in the range from 5 to 15 eV, plasma density in the range from 10/sup 1… more
Date: May 1, 1986
Creator: Hirooka, Y.; Goebel, D. M.; Conn, R. W.; Leung, W. K. & Campbell, G. A.
Partner: UNT Libraries Government Documents Department
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Microstructural characterization of primary coolant pipe steel

Description: Atom probe field-ion microscopy, analytical electron microscopy, and optical microscopy have been used to investigate the changes that occur in the microstructure of cast CF 8 primary coolant pipe stainless steel after long term thermal aging. The cast duplex microstructure consisted of austenite with 15% delta-ferrite. Investigation of the aged material revealed that the ferrite spinodally decomposed into a fine scaled network of ..cap alpha.. and ..cap alpha..'. A fine G-phase precipitate was… more
Date: January 1, 1986
Creator: Miller, M. K. & Bentley, J.
Partner: UNT Libraries Government Documents Department
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Cladding separate effects study: HSST seventh irradiation series

Description: The existence of a layer of tough weld overlay cladding on the interior of a light-water reactor pressure vessel could mitigate the damage caused during certain overcooling transients. This would occur if the cladding can keep a short surface flaw, which would otherwise become long, from growing either by impeding crack initiation or by arresting a running crack. Two aspects of cladding behavior critical to assessing its potential benefit are being examined within the HSST Program: irradiation … more
Date: January 1, 1986
Creator: Corwin, W.R.
Partner: UNT Libraries Government Documents Department
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Modeling a hydroform springback problem

Description: A shallow stretch - draw sheet forming operation performed on a hydroform machine was modeled with the finite element codes NIKE2D and ADINA78. The forming process produces a a thin spherical shell segment with a flange. The final shape of the part differs substantially from the die because of springback, yet the part must be very accurate to meet the specified tolerance. This difficult problem was chosen specifically to determine the limits of accuracy of currently available codes. NIKE2D prod… more
Date: January 1, 1986
Creator: Korzekwa, D. A. & Guerra, F. M.
Partner: UNT Libraries Government Documents Department
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Corrosion of Fe-Cr-Mn alloys in thermally convective lithium

Description: A series of austenitic Fe-Cr-Mn steels was exposed to circulating lithium at temperatures up to 500/sup 0/C. Two groups of the alloys, which contained 12 to 30 wt % Mn and 2 to 20 wt % Cr, were sequentially exposed for periods greater than 3000 h in a type 316 stainless steel thermal convection loop. Mass transfer of manganese caused very large weight losses from the steels containing 30 wt % Mn. However, the actual magnitude of corrosion losses for alloys containing 12 to 20 wt % Mn was diffic… more
Date: January 1, 1986
Creator: Tortorelli, P. F. & DeVan, J. H.
Partner: UNT Libraries Government Documents Department
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Comparison of swelling for structural materials on neutron and ion irradiation

Description: The swelling of V-base alloys, Type 316 stainless steel, Fe-25Ni-15Cr alloys, ferritic steels, Cu, Ni, Nb-1% Zr, and Mo on neutron irradiation is compared with the swelling for these materials on ion irradiation. The results of this comparison show that utilization of the ion-irradiation technique provides for a discriminative assessment of the potential for swelling of candidate materials for fusion reactors.
Date: March 1, 1986
Creator: Loomis, B. A.
Partner: UNT Libraries Government Documents Department
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Program of United States-Japan collaborative testing in HFIR and ORR

Description: The objective of the program of US-Japan collaborative testing in HFIR and ORR is to investigate the response of austenitic stainless steels to levels of neutron radiation damage anticipated in fusion reactors. Emphasis is placed on United States and Japanese type 316 stainless steels and prime candidate alloys (PCA), but improved alloys are also included. The program consists of eight HFIR target capsules and two ORR spectral tailoring capsules with test temperatures of 60 to 600/sup 0/C and f… more
Date: 1986~
Creator: Scott, J.L.; Grossbeck, M.L.; Hishinuma, A.; Kondo, T.; Rowcliffe, A.F. & Tanaka, M.P.
Partner: UNT Libraries Government Documents Department
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Technique for megabar controlled strain experiments

Description: This design allows in one shot one experiment a range of pressures from 12 to 170 GPa and a selectable strain range (0 to 55%) in 304 stainless steel with 100% recovery. Development of the application of griding has enabled correlation, locally, of pressure and strain with structure and properties at a strain rate of 10/sup 6//s. Appropriate variations in momentum trap design can control strain in cylindrical implosion shock experiments. Pedestal type traps have shown significant improvement in… more
Date: January 1, 1986
Creator: Staudhammer, K.P. & Johnson, K.A.
Partner: UNT Libraries Government Documents Department
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Operation of the ORNL ECR source

Description: During the past year, the ORNL ECR source has fully demonstrated its capability for providing the high charge state, high current beams required for our group's atomic physics research program. The ECR source, which is dedicated completely for use in our investigations of the collisional properties of multicharged ions, has permitted considerable expansion of research in some areas, and has opened other areas that were experimentally unaccessible to us previously. A partial list of publications… more
Date: January 1, 1986
Creator: Meyer, F.W.
Partner: UNT Libraries Government Documents Department
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Design rule for fatigue of welded joints in elevated-temperature nuclear components

Description: Elevated-temperature weldment fatigue failures have occurred in several operating liquid-metal reactor plants. Yet, ASME Code Case N-47, which governs the design of such plants in the United States, does not currently address the Code Subgroup on Elevated Temperature Design recently proposed a fatigue strength reduction factor for austenitic and ferritic steel weldments. The factor is based on a variety of weld metal and weldment fatigue data generated in the United States, Europe, and Japan. T… more
Date: January 1, 1986
Creator: O'Connor, D.G. & Corum, J.M.
Partner: UNT Libraries Government Documents Department
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Independent analysis of selected core-concrete interaction and fission product release experiments with CORCON-MOD2 and VANESA

Description: The discrepancies between experimental findings and the Reactor Safety Study predictions, as well as the rapidly developing data base enabling phenomenological modeling of core-concrete interactions and ex-vessel fission product release, have prompted the development of several new computer models of core-concrete interactions and fission product release during severe accidents. Two such models are the CORCON-MOD2 model of core-concrete interactions and the VANESA model of ex-vessel aerosol and… more
Date: January 1, 1986
Creator: Greene, G.A. & Sanborn, Y.
Partner: UNT Libraries Government Documents Department
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FY 1984 and FY 1985 geochemistry and materials studies in support of the Magma Energy Extraction Program

Description: Geochemistry and materials studies are being performed in support of the Magma Energy Extraction Program. The work is largely restricted to: (1) characterizing magmatic environments at sites of interest, (2) testing engineering materials in laboratory simulated magmatic environments, (3) investigating chemical mass transport effects inherent in designs for direct contact heat exchangers, and (4) evaluating degassing hazards associated with drilling into and extracting energy from shallow magma.… more
Date: April 1, 1986
Creator: Westrich, H. R.; Weirick, L. J.; Cygan, R. T.; Reece, M.; Hlava, P. F.; Stockman, H. W. et al.
Partner: UNT Libraries Government Documents Department
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