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Heavy-section steel irradiation program. Semiannual progress report, October 1996--March 1997

Description: Maintaining the integrity of the reactor pressure vessel (RPV) in a light-water-cooled nuclear power plant is crucial in preventing and controlling severe accidents that have the potential for major contamination release. Because the RPV is the only key safety-related component of the plant for which a redundant backup system does not exist, it is imperative to fully understand the degree of irradiation-induced degradation of the RPV`s fracture resistance that occurs during service. For this reason, the Heavy-Section Steel Irradiation (HSSI) Program has been established. Its primary goal is to provide a thorough, quantitative assessment of the effects of neutron irradiation on the material behavior and, in particular, the fracture toughness properties of typical pressure-vessel steels as they relate to light-water RPV integrity. Effects of specimen size; material chemistry; product form and microstructure; irradiation fluence, flux, temperature, and spectrum; and postirradiation annealing are being examined on a wide range of fracture properties. The HSSI Program is arranged into eight tasks: (1) program management, (2) irradiation effects in engineering materials, (3) annealing, (4) microstructural analysis of radiation effects, (5) in-service irradiated and aged material evaluations, (6) fracture toughness curve shift method, (7) special technical assistance, and (8) foreign research interactions. The work is performed by the Oak Ridge National Laboratory.
Date: February 1, 1998
Creator: Rosseel, T.M.
Partner: UNT Libraries Government Documents Department

Heavy-Section Steel Irradiation (HSSI) Program (W6953) Monthly Letter Status Report - March 2001 - ORNL/HSSI (W6953) MLSR-2001/6.

Description: The primary goal of the Heavy-Section Steel Irradiation (HSSI) Program is to provide a thorough, quantitative assessment of the effects of neutron irradiation on the material behavior, and in particular the fracture toughness properties, of typical pressure vessel steels as they relate to light-water reactor pressure vessel (RPV) integrity. The program includes studies of the effects of irradiation on the degradation of mechanical and fracture properties of vessel materials augmented by enhanced examinations and modeling of the accompanying microstructural changes. Effects of specimen size; material chemistry; product form and microstructure; irradiation fluence, flux, temperature, and spectrum; and post-irradiation mitigation are being examined on a wide range of fracture properties. This program will also maintain and upgrade computerized databases, calculational procedures, and standards relating to RPV fluence-spectra determinations and embrittlement assessments. Results from the HSSI studies will be incorporated into codes and standards directly applicable to resolving major regulatory issues that involve RPV irradiation embrittlement such as pressurized-thermal shock, operating pressure-temperature limits, low-temperature overpressurization, and the specialized problems associated with low upper-shelf welds. Six technical tasks and one for program management are now contained in the HSSI Program.
Date: April 20, 2001
Creator: Rosseel, T. M.
Partner: UNT Libraries Government Documents Department

HSSI Monthly Letter Status Report for (W6953) December 2000.

Description: This report is issued monthly by the staff of the Heavy-Section Steel Irradiation (HSSI) Program (JCN:W6953) to provide the Nuclear Regulatory Commission (NRC) staff with summaries of technical highlights, important issues, and financial and milestone status within the program. This report gives information on several topics corresponding to events during the reporting month: (1) overall project objective, (2) technical activities, (3) meetings and trips, (4) publications and presentations, (5) property acquired, (6) problem areas, and (7) plans for the next reporting period. Next the report gives a breakdown of overall program costs as well as cost summaries and earned-value-based estimates for performance for the total program and for each of the eight program tasks. The seven tasks correspond to the 189, dated March 23, 1998, and modified by the inclusion of the former ''Embrittlement Data Base and Dosimetry Evaluation'' Program, JCN 6164 in March, 1999. The final part of the report provides financial status for all tasks and status reports for selected milestones within each task. The task milestones address the period from April 1998 to December 2000, while the individual task budgets address the period from October 1999 to December 2000. Beginning in October, 1992, the monthly business calendar of the Oak Ridge National Laboratory was changed and no longer coincides with the Gregorian/Julian calendar. The business month now ends earlier than the last day of the calendar month to allow adequate time for processing required financial reports to the Department of Energy. The precise reporting period for each month is indicated on the financial and milestone charts by including the exact start and finish dates for the current business month.
Date: February 1, 2001
Creator: Rosseel, T. M.
Partner: UNT Libraries Government Documents Department

Heavy-Section Steel Irradiation Program

Description: Maintaining the integrity of the reactor pressure vessel (RPV) in a light-water-cooled nuclear power plant is crucial in preventing and controlling severe accidents that have the potential for major contamination release. Because the RPV is the only key safety-related component of the plant for which a redundant backup system does not exist, it is imperative to fully understand the degree of irradiation-induced degradation of the RPV's fracture resistance that occurs during service. For this reason, the Heavy-Section Steel Irradiation (HSSI) Program has been established.
Date: April 2000
Creator: Rosseel, T. M.
Partner: UNT Libraries Government Documents Department

U.S. NRC Embrittlement Data Base (EDB)

Description: Large amounts of data obtained from surveillance capsules and test reactor experiments are needed, comprising many different materials and different irradiation conditions, to develop generally applicable damage prediction models that can be used for industry standards and regulatory guides. Version 1 of the Embrittlement Data Base (EDB) [I] is such a comprehensive collection of such data resulting from the merging of the Power Reactor Embrittlement Data Base (PR-EDB) [2] and the Test Reactor Embrittlement Data Base (TR-EDB) [3]. Fracture toughness data were also integrated into Version 1 of the EDB. The EDB data files are in dBASE format and can be accessed with a personal computer using the DOS or WINDOWS operating system. A utility program has been written to investigate radiation embrittlement using this data base. The utility program is used to retrieve and select specific data, manipulate data, display data to the screen or printer, and to tit and plot Charpy impact data.
Date: September 12, 1999
Creator: Pace, J.V.; Rosseel, T.M. & Wang, J.A.
Partner: UNT Libraries Government Documents Department

Heavy-Section Steel Irradiation (HSSI) Program (W6953) Monthly Letter Status Report - February 2001 - ORNL/HSSI (6953) MLSR-2001/5.

Description: The primary goal of the Heavy-Section Steel Irradiation (HSSI) Program is to provide a thorough, quantitative assessment of the effects of neutron irradiation on the material behavior, and in particular the fracture toughness properties, of typical pressure vessel steels as they relate to light-water reactor pressure vessel (RPV) integrity. The program includes studies of the effects of irradiation on the degradation of mechanical and fracture properties of vessel materials augmented by enhanced examinations and modeling of the accompanying microstructural changes. Effects of specimen size; material chemistry; product form and microstructure; irradiation fluence, flux, temperature, and spectrum; and post-irradiation mitigation are being examined on a wide range of fracture properties. This program will also maintain and upgrade computerized databases, calculational procedures, and standards relating to RPV fluence-spectra determinations and embrittlement assessments. Results from the HSSI studies will be incorporated into codes and standards directly applicable to resolving major regulatory issues that involve RPV irradiation embrittlement such as pressurized-thermal shock, operating pressure-temperature limits, low-temperature overpressurization, and the specialized problems associated with low upper-shelf welds. Six technical tasks and one for program management are now contained in the HSSI Program.
Date: March 26, 2001
Creator: Rosseel, T. M.
Partner: UNT Libraries Government Documents Department

Heavy-Section Steel Irradiation (HSSI) Program (W6953) Monthly Letter Status Report - January 2001 - ORNL/HSSI (6953) MLSR-2001/4

Description: This report is issued monthly by the staff of the Heavy-Section Steel Irradiation (HSSI) Program (JCN:W6953) to provide the Nuclear Regulatory Commission (NRC) staff with summaries of technical highlights, important issues, and financial and milestone status within the program. This report gives information on several topics corresponding to events during the reporting month: (1) overall project objective, (2) technical activities, (3) meetings and trips, (4) publications and presentations, (5) property acquired, (6) problem areas, and (7) plans for the next reporting period. Next the report gives a breakdown of overall program costs as well as cost summaries and earned-value-based estimates for performance for the total program and for each of the eight program tasks. The seven tasks correspond to the 189, dated March 23, 1998, and modified by the inclusion of the former ''Embrittlement Data Base and Dosimetry Evaluation'' Program, JCN 6164 in March, 1999. The final part of the report provides financial status for all tasks and status reports for selected milestones within each task. The task milestones address the period from October 2000 to March 2003, while the individual task budgets address the period from October 2000 to February 2001. Beginning in October, 1992, the monthly business calendar of the Oak Ridge National Laboratory was changed and no longer coincides with the Gregorian/Julian calendar. The business month now ends earlier than the last day of the calendar month to allow adequate time for processing required financial reports to the Department of Energy. The precise reporting period for each month is indicated on the financial and milestone charts by including the exact start and finish dates for the current business month.
Date: February 20, 2001
Creator: Rosseel, T. M.
Partner: UNT Libraries Government Documents Department

Synchrotron radiation as a source for quantitative XPS: advantages and consequences

Description: Synchrotron radiation (SR) has a variety of properties which make it an attractive source for quantitative x-ray photoelectron spectroscopy (XPS). Among the most significant are high intensity and tunability. In addition, the intensity of the dispersed radiation is comparable to laboratory line sources. Synchrotron radiation is also a clean source, i.e., it will not contaminate the sample, because it operates under ultra-high vacuum conditions. We have used these properties to demonstrate the advantages of SR as a source for quantitative XPS. We have also found several consequences associated with this source which can either limit its use or provide unique opportunities for analysis and research. Using the tunability of SR, we have measured the energy dependence of the 3p photoionization cross sections of Ti, Cr, and Mn from 50 to 150 eV above threshold at the University of Wisconsin's Tantalus electron-storage ring.
Date: January 1, 1986
Creator: Rosseel, T.M.; Carlson, T.A.; Negri, R.E.; Beall, C.E. & Taylor, J.W.
Partner: UNT Libraries Government Documents Department

Heavy-ion-induced x-ray satellite emission as a chemical probe

Description: Advances in energy technology often require correspondidng advances in materials fabrication and characterization. Among the new techniques being developed for the improved characterization of materials is an x-ray fluorescence method which uses heavy ions for excitation. High resolution measurements of heavy-ion excited x-ray spectra have revealed a series of prominent satellite lines in addition to the normal emission lines. It has been shown that these satellites display intensity variations indicative of the chemical state or environment of the emitting target atom and the projectile velocity. In order to evaluate heavy-ion induced x-ray satellite emission (HIXSE) as a chemical probe, we have examined a series of sulfur compounds and titanium, vanadium and molybdenum alloys and compounds. Results will be presented which demonstrate the chemical sensitivity of this technique, the range of elements which can be analyzed and the potential for applications to real chemical and materials problems.
Date: January 1, 1983
Creator: Rosseel, T.M.; Dale, J.M.; Hulett, L.D.; Krause, H.F.; Raman, S.; Vane, C.R. et al.
Partner: UNT Libraries Government Documents Department

Surface areas by positron annihilation spectroscopy

Description: Positron annihilation spectroscopy (PAS) is a technique for measuring the length of time that a positron exists after being injected into a specific material. Lifetime measurements have been used for studying defects in metals. These imperfections affect the localized electron densities which in turn influence the lifetime of the positron before annihilation occurs. Electron density differences are also associated with surfaces. This paper describes the PAS technique and shows a correlation between positron annihilation intensities and surface areas of some fumed amorphous silicas.
Date: January 1, 1985
Creator: Dale, J.M.; Rosseel, T.M.; Hulett, L.D.; Venkateswaran, K.; Jean, Y.C. & Fuller, E.L.
Partner: UNT Libraries Government Documents Department

Preliminary results from Charpy impact testing of irradiated JPDR weld metal and commissioning of a facility for machining of irradiated materials

Description: Forty two full-size Charpy specimens were machined from eight trepans that originated from the Japan Power Demonstration Reactor (JPDR). They were also successfully tested and the preliminary results are presented in this report. The trends appear to be reasonable with respect to the location of the specimens with regards to whether they originated from the beltline or the core regions of the vessel, and also whether they were from the inside or outside regions of the vessel wall. A short synopsis regarding commissioning of the facility to machine irradiated materials is also provided.
Date: September 1, 1999
Creator: Iskander, S.K.; Hutton, J.T.; Creech, L.E.; Nanstad, R.K.; Manneschmidt, E.T.; Rosseel, T.M. et al.
Partner: UNT Libraries Government Documents Department

Advances in high-resolution studies of the chemical effects in the molybdenum L heavy-ion-induced x-ray satellite emission (HIXSE) spectra

Description: High-resolution measurements of the molybdenum L heavy-ion-induced x-ray satellite emission (HIXSE) spectra of a series of Mo alloys and compounds have been obtained with a new, high-efficiency, high-resolution Bragg crystal spectrometer in the von Hamos geometry. The improved resolution (5 eV at 2.3 keV) is sufficient to reveal the L/sup n/M/sup m/ configuration lines in the L..cap alpha.. and L..beta.. hypersatellite bands. Both sets of lines exhibit the same trend in the variation of the relative yield distribution with the chemical environment as was observed for KL/sup n/ lines of lower Z targets. Difference spectra, using elemental molybdenum as a subtrahend, enhance the systematic variation. These results confirm the analysis and conclusions of lower resolution studies. They also indicate a potential for even greater sensitivity to the chemical environment.
Date: January 1, 1986
Creator: Rosseel, T.M.; Dale, J.M.; Hulett, L.D.; Pepmiller, P.L.; Vane, C.R.; Walkiewicz, T.A. et al.
Partner: UNT Libraries Government Documents Department

Electron ion interactions in crystal channels: Collisions in ultra-dense electron media

Description: Dielectronic excitation of H-like S, Ca and Ti is shown to occur in the dense electron gas of a crystal channel. Cross sections for collisional ionization of the short lived excited states can then be determined. Ionic excitation can also be achieved by resonant coherent excitation in which case specific m states can be excited for further study. 12 refs., 8 figs.
Date: January 1, 1990
Creator: Datz, S.; Dittner, P.F.; Gomez del Campo, J.; Krause, H.F.; Rosseel, T.M. & Vane, C.R.
Partner: UNT Libraries Government Documents Department

L-shell x-ray production cross sections in Nd, Gd, Ho, Yb, Au and Pb for 25-MeV carbon and 32-MeV oxygen ions

Description: L-shell x-ray production cross sections in /sub 60/Nd, /sub 64/Gd, /sub 67/Ho, /sub 70/Yb, /sub 79/Au and /sub 82/Pb have been measured for incident 25 MeV /sub 6//sup 12/C/sup +q/(q = 4,5,6) and 32 MeV /sub 8//sup 16/O/sup +q/(q = 5,7,8) ions. Measurements were made on targets ranging in thickness from 1 to 100 ..mu..g/cm/sup 2/. Echancement in the L-shell x-ray production cross section for projectiles with one or two K-shell vacancies over those for projectiles with no K-shell vacancies is observed. The sum of direct ionization to the continuum (DI) plus electron capture (EC) to the L,M,N ... shells and EC to the K-shell of the projectile have been extracted from the data. Calculations in the first Born approximation are approx. 10 times larger than the data. Predictions of the ECPSSR theory that accounts for the energy-loss, Coulomb deflection, perturbed-stationary state, and relativistic effects are in good agreement with the data for both ions.
Date: January 1, 1984
Creator: Andrews, M.C.; McDaniel, F.D.; Duggan, J.L.; Mehta, R.; Lapicki, G.; Miller, P.D. et al.
Partner: UNT Libraries Government Documents Department

L- and M-shell x-ray production cross sections of Nd, Gd, Ho, Yb, Au, and Pb by 25-MeV carbon and 32-MeV oxygen ions

Description: Article discussing research on L- and M-shell x-ray production cross sections of Nd, Gd, Ho, Yb, Au, and Pb by 25-MeV carbon and 32-MeV oxygen ions.
Date: October 15, 1987
Creator: Andrews, M. C.; McDaniel, Floyd Del. (Floyd Delbert), 1942-; Duggan, Jerome L.; Miller, P. D.; Pepmiller, P. L.; Krause, H. F. et al.
Partner: UNT College of Arts and Sciences

High-resolution heavy-ion-induced x-ray satellite emission study of implanted sulfur as a probe of co-implanted oxygen in an oxide substrate

Description: Using high-resolution measurements, the relative fluorescence yields of the sulfur K{sub {alpha}}L{sup n} x-ray satellite lines produced by 24 MeV Si{sup q+} ion irradiation of a series of quartz glass targets co-implanted to equal doses and depths of sulfur and oxygen have been obtained and compared to the yields from a series of quartz glass targets implanted to the same depth with sulfur only. The data exhibit lower yields in the higher-order KL{sup n} satellite lines for the co-implanted oxygen targets but similar dose dependent curves. These results are consistent with oxygen increasing the valence electron density of the local sulfur environment. It also suggests that, with an appropriate choice of a probe ion, HIXSE may be capable of detecting impurity ions in matrices that normally mask the impurity, e.g., oxygen in oxide substrates. 10 refs., 3 figs.
Date: January 1, 1990
Creator: Rosseel, T.M.; Young, J.P.; Vane, C.R.; Zuhr, R.A. (Oak Ridge National Lab., TN (USA)) & Peterson, R.S. (University of the South, Sewanee, TN (USA). Dept. of Physics)
Partner: UNT Libraries Government Documents Department

Implications of heavy-ion-induced satellite x-ray emission. III. Chemical effects in high resolution sulfur K/sub. cap alpha. / x-ray spectra

Description: High resolution (approx. 7 eV at 2.3 keV) sulfur K/sub ..cap alpha../ x-ray spectra have been obtained for a series of sulfur compound targets under heavy ion impact at the Holified Heavy Ion Facility. The spectra observed are dominated by a series of satellite peaks arising from varying degrees of L-shell ionization at the time of x-ray emission. Each spectral profile has been parameterized by a single variable p/sub L/, the apparent average L-shell ionization probability. Correlations are evident between p/sub L/ and the corresponding sulfur atom chemical environment. Much stronger correlations are however found for variations of some individual peak intensities with specific chemical parameters. Comparison of results for Ar/sup q+/ and Kr/sup q+/ projectiles shows that while L-shell ionization probability has increased, chemical sensitivity has apparently saturated.
Date: January 1, 1983
Creator: Vane, C.R.; Hulett, L.D. Jr.; Kahane, S.; McDaniel, F.D.; Milner, W.T.; Raman, S. et al.
Partner: UNT Libraries Government Documents Department

Resonant coherent excitation of Mg sup 11+ : Electronic collisions of state specified short-lived excited states in a crystal channel

Description: Hydrogenic ions passing through axial and planar channels can be excited from n = 1 to n = 2 when the frequency of perturbation by the atoms in the crystal spaced a distance d apart comes into resonance with the spacing between eigenstates i and j {Delta}E{sub ij} = hK(v{sub i}/d) where K is a harmonic 1,2,3{hor ellipsis} of the (v{sub i}/d) frequency. The degeneracy in the n = 2 levels is removed; first by the assymetry in the crystal field and second by Stark mixing of 2s with 2p{sub x} which is caused by the wake field. Thus, the resonant frequency, and hence velocity, for excitation to 2p{sub x,y} is different than that for 2p{sub x} and they can be excited selectively. In the present work we used Mg{sup 11+}, where the n = 2 ionization cross section is small enough to permit escape of some of the excited ions from the crystal without being ionized by subsequent collisions and with the subsequent emission of radiation. Since we can excite different orientations of the ion selectively by varying the velocity we can measure the separate ionization cross sections for these states by determining the yields of totally stripped ions compared to those which emit a Ly {alpha} x-ray. A comparison of the two channels shows that the probability of escape from the crystal without ionizations is greater for ions in the 2p{sub x} state than those in the 2p{sub x,y} state. These RCE data and are presented as proof of principal for experiments which measure electron bombardment ionization cross sections for short lived excited states with specific polarization.
Date: January 1, 1990
Creator: Datz, S.; Dittner, P.F.; Gomez del Campo, J.; Krause, H.F.; Rosseel, T.M.; Vane, C.R. (Oak Ridge National Lab., TN (USA)) et al.
Partner: UNT Libraries Government Documents Department