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Crack-growth-rate testing of candidate waste container materials

Description: Fracture-mechanics crack growth tests were conducted on 25.4-mm-thick compact tension specimens of Types 304L and 316L stainless steel (SS) and Incoloy 825 at 93{degree}C and 1 atmosphere of pressure is simulated J-13 well water, which is representative of the groundwater at the Yucca Mountain site in Nevada that is proposed for a high-level nuclear waste repository. Crack growth rates were measured under various load conditions: load ratios (R) of 0.5--1.0, frequencies of 10{sup {minus}3}{minus}1 Hz, rise times of 1--1000 s, and peak stress intensities of 25--40 MPa{center_dot}m{sup 1/2}. The measured crack growth rates are bounded by the predicted rates from the current ASME Section XI correlation for fatigue crack growth rates of austenitic stainless steel in air. Environmentally accelerated crack growth was not evident in any of the three materials under the test conditions investigated.
Date: December 31, 1991
Creator: Park, J.Y.; Shack, W.J. & Diercks, D.R.
Partner: UNT Libraries Government Documents Department

Microstructural and solidification cracking evaluation of electron beam welds in 304L

Description: Weld hot cracking of stainless steels is a major materials-related problem in the welding industry. This present investigation evaluates the crack susceptibility of highly-constrained EB welds made in materials whose DeLong ferrite potentials range from zero to nine FN. In addition, the effect of piece part strength level on cracking is examined. This study has revealed that these deep penetration EB welds have regions that solidify as primary austenite, even when the DeLong ferrite potential is as high as 9 FN. This points out the critical role that solidification rate plays in the crack susceptibility of these highly restrained welds. In addition, 0 FN to 0 FN welds had primarily transverse cracks while 6 FN to 0 FN welds had primarily centerline cracks. Of particular interest is the observation that cracks still occur if a high ferrite (greater than 6 FN) component is welded to a zero FN component. Cracking is always associated with regions which solidify as primary austenite and these cracks occur because there are areas in the weld which do not mix. Thus it is not a recommended production practice to compensate for low ferrite in one piece part with high ferrite in its mate. Finally, it is shown that a DeLong FN threshold of 4 to prevent cracking in EB welds in not valid. 21 refs., 16 figs.
Date: January 1, 1991
Creator: Sturgill, P.L.; Campbell, R.D. & Henningsen, J.L.
Partner: UNT Libraries Government Documents Department

Reactor Materials Program: Mechanical properties of irradiated Types 304 and 304L stainless steel weldment components

Description: The vessels (reactor tanks) of the Savannah River Site nuclear production reactors constructed in the 1950's are comprised of Type 304 stainless steel with Type 308 stainless steel weld filler. Irradiation exposure to the reactor tank sidewalls through reactor operation has caused a change in the mechanical properties of these materials. A database of as-irradiated mechanical properties for site-specific materials and irradiation conditions has been produced for reactor tank structural analyses and to quantify the effects of radiation-induced materials degradation for evaluating reactor service life. The data has been collected from the SRL Reactor Materials Program (RMP) irradiations and testing of archival stainless steel weldment components and from previous SRL programs to measure properties of irradiated reactor Thermal Shield weldments and reactor tank (R-tank) sidewall material. Irradiation programs of the RMP are designed to quantify mechanical properties at tank operating temperatures following irradiation to present and future tank wall maximum exposure conditions. The exposure conditions are characterized in terms of fast neutron fluence (E{sub n} > 0.1 MeV) and displacements per atom (dpa){sup 3}. Tensile properties, Charpy-V notch toughness, and elastic-plastic fracture toughness were measured for base, weld, and weld heat-affected zone (HAZ) weldment components from archival piping specimens following a Screening Irradiation in the University of Buffalo Reactor (UBR) and following a Full-Term Irradiation in the High Flux Isotope Reactor (HFIR).
Date: December 1, 1991
Creator: Sindelar, R.L. & Caskey, G.R. Jr.
Partner: UNT Libraries Government Documents Department

Fabrication and closure development of nuclear waste disposal containers for the Yucca Mountain Project: Status report

Description: In GFY 89, a project was underway to determine and demonstrate a suitable method for fabricating thin-walled monolithic waste containers for service within the potential repository at Yucca Mountain. A concurrent project was underway to determine and demonstrate a suitable closure process for these containers after they have been filled with high-level nuclear waste. Phase 1 for both the fabrication and closure projects was a screening phase in which candidate processes were selected for further laboratory testing in Phase 2. This report describes the final results of the Phase 1 efforts. It also describes the preliminary results of Phase 2 efforts.
Date: September 1, 1991
Creator: Domian, H.A.; Robitz, E.S.; Conrardy, C.C.; LaCount, D.F.; McAninch, M.D.; Fish, R.L. et al.
Partner: UNT Libraries Government Documents Department

The effects of tritium and decay helium on the fracture toughness properties of stainless steels

Description: J-integral fracture mechanics techniques and scanning electron microscopy observations were used to investigate the effects of tritium and its decay product, helium-3, on Types 304L, 316L, 21-6-9, A286, and JBK-75 (Modified A286) stainless steels. Tritium-exposed samples of each steel had lower fracture toughness values and less resistance to stable crack growth than control samples. Type 316L stainless steel was more resistant to the embrittling effects of tritium and decay helium than the other steels.
Date: December 31, 1991
Creator: Morgan, M. J.
Partner: UNT Libraries Government Documents Department

Evaluation of remote smearing of DWPF canistered waste forms

Description: The Savannah River Site (SRS) is evaluating the variables of the remote smearing process for monitoring transferable contamination on the waste glass canisters at the Defense Waste Processing Facility (DWPF). Smearing for transferable contamination is typically done by hand, but in this case, due to the nature of the high level waste within the canisters, remote smearing is required. The effectiveness of the smear pad was determined under varying conditions (distance traveled, force applied, and canister surface), as well as the relative importance of these factors. It was concluded that the remote smear is more reliable than the hand smear.
Date: December 31, 1991
Creator: Payne, C. H. & Rankin, W. N.
Partner: UNT Libraries Government Documents Department

Corrosion testing of Type 304L stainless steel for waste tank applications

Description: AISI Type 304L stainless steel will be the material of construction for hazardous waste storage tanks. The corrosion behavior of 304L was characterized in simulated waste solutions using potentiodynamic polarization, electrochemical impedance spectroscopy and long term immersion tests. The results were correlated to assess the use of corrosion characteristics determined by electrochemical techniques for predicting long term corrosion behavior. The corrosion behaviors of Type A537 carbon steel and Incoloy 825 were also evaluated. A good correlation was found between the results from the electrochemical techniques and the immersion tests.
Date: December 31, 1991
Creator: Wiersma, B. J. & Mickalonis, J. I.
Partner: UNT Libraries Government Documents Department

Corrosion of 304L and 316 in gadolinium nitrate neutron poison solutions

Description: Pitting corrosion has occurred on AISI Type 304L stainless steel (304L) conductivity probes used to monitor liquid levels of gadolinium nitrate neutron poison solutions (GPS). An electrochemical and immersion test program has led to a better understanding of the cause of corrosion of 304L probes. Results indicate that the alternating voltage applied to the probes to monitor contact with solution is the primary factor in the corrosion of the probes. A chloride-containing dye and low pH also contribute to the corrosion process, but appear to play a secondary role. AISI Type 316 stainless steel (316) was found to behave similarly to 304L in GPS, while nickel-based alloys such as Hastelloy G30, Hastelloy C22, and Inconel 625 were found to be more susceptible to corrosion as compared to 304L.
Date: December 31, 1991
Creator: Chandler, G. T. & Anderson, M. H.
Partner: UNT Libraries Government Documents Department

Reactor Materials Program: Mechanical properties of irradiated Types 304 and 304L stainless steel weldment components

Description: The vessels (reactor tanks) of the Savannah River Site nuclear production reactors constructed in the 1950`s are comprised of Type 304 stainless steel with Type 308 stainless steel weld filler. Irradiation exposure to the reactor tank sidewalls through reactor operation has caused a change in the mechanical properties of these materials. A database of as-irradiated mechanical properties for site-specific materials and irradiation conditions has been produced for reactor tank structural analyses and to quantify the effects of radiation-induced materials degradation for evaluating reactor service life. The data has been collected from the SRL Reactor Materials Program (RMP) irradiations and testing of archival stainless steel weldment components and from previous SRL programs to measure properties of irradiated reactor Thermal Shield weldments and reactor tank (R-tank) sidewall material. Irradiation programs of the RMP are designed to quantify mechanical properties at tank operating temperatures following irradiation to present and future tank wall maximum exposure conditions. The exposure conditions are characterized in terms of fast neutron fluence (E{sub n} > 0.1 MeV) and displacements per atom (dpa){sup 3}. Tensile properties, Charpy-V notch toughness, and elastic-plastic fracture toughness were measured for base, weld, and weld heat-affected zone (HAZ) weldment components from archival piping specimens following a Screening Irradiation in the University of Buffalo Reactor (UBR) and following a Full-Term Irradiation in the High Flux Isotope Reactor (HFIR).
Date: December 1, 1991
Creator: Sindelar, R. L. & Caskey, G. R. Jr.
Partner: UNT Libraries Government Documents Department

Supplementary safety system corrosion studies

Description: This memorandum presents experimental data from electrochemical and immersion tests to support the continued use of two sections of nonconforming steel in the Supplementary Safety System. The Reactor Corrosion Mitigation Committee met on May 16, 1991 to evaluate materials that had been installed in the SSS. The materials lacked complete Corrosion Evaluation (CE) and/or Certified Mill Test Reports and had been installed during recent modifications (Project S-4332). Items that lacked proper documentation included AISI Type 304 stainless steel (304) instrument tubing (0.375`` OD) associated with the pressure transmitters and a two-foot section of 304 pipe located on the far side of the system downstream of the pneumatic valves. Cyclic potentiodynamic polarization scans were performed on sensitized and solution-annealed 304 samples in as-mixed and acidified Gd(NO{sub 3}){sub 3}, or ``ink``, solutions at room temperature to determine the susceptibility of 304 to localized corrosion in this environment. No localized attack was observed on the solution annealed or sensitized 304 in the Gd(NO{sub 3}){sub 3} solution. These tests revealed no significant differences in the behavior of the sensitized and solution-annealed 304 in gadolinium nitrate solution. Therefore, localized corrosion of the nonconforming components is not anticipated, and the performance of the nonconforming components should not differ from that of corrosion evaluated and certified materials. Previous studies have shown that AISI Type 304L stainless steel (304L) did not pit during a three-month exposure in gadolinium nitrate solutions of pH 2 or 5. These combined results support the continued use of the nonconforming steels until replacement can be made at the next scheduled long shut-down.
Date: May 21, 1991
Creator: Anderson, M. H. & Wiersma, B. J.
Partner: UNT Libraries Government Documents Department

Corrosion testing of Type 304L stainless steel for waste tank applications

Description: AISI Type 304L stainless steel will be the material of construction for hazardous waste storage tanks. The corrosion behavior of 304L was characterized in simulated waste solutions using potentiodynamic polarization, electrochemical impedance spectroscopy and long term immersion tests. The results were correlated to assess the use of corrosion characteristics determined by electrochemical techniques for predicting long term corrosion behavior. The corrosion behaviors of Type A537 carbon steel and Incoloy 825 were also evaluated. A good correlation was found between the results from the electrochemical techniques and the immersion tests.
Date: January 1, 1991
Creator: Wiersma, B.J. & Mickalonis, J.I.
Partner: UNT Libraries Government Documents Department

The effect of yield strength on side-bonding upset welds

Description: During the course of 9{degree} tapered side-bonding resistance upset weld development at Mound, various studies have been conducted to evaluate the effect of yield strength on welds in 304L stainless steel. The results of these studies have concluded that at high yield strengths there may be a minor reduction in the length of Class 2 or better bond. Satisfactory welds have been produced with materials having yield strengths ranging from 36.0 to 141.0 ksi. However, when body yield strengths exceed 80.0 ksi a minor decrease in bond lengths begins. A significant inverse relationship between stem yield strength and bond length was shown to exist. 8 refs., 9 figs., 10 tabs.
Date: September 24, 1991
Creator: Miller, R.G. & Perkins, M.A.
Partner: UNT Libraries Government Documents Department

Corrosion of 304L and 316 in gadolinium nitrate neutron poison solutions

Description: Pitting corrosion has occurred on AISI Type 304L stainless steel (304L) conductivity probes used to monitor liquid levels of gadolinium nitrate neutron poison solutions (GPS). An electrochemical and immersion test program has led to a better understanding of the cause of corrosion of 304L probes. Results indicate that the alternating voltage applied to the probes to monitor contact with solution is the primary factor in the corrosion of the probes. A chloride-containing dye and low pH also contribute to the corrosion process, but appear to play a secondary role. AISI Type 316 stainless steel (316) was found to behave similarly to 304L in GPS, while nickel-based alloys such as Hastelloy G30, Hastelloy C22, and Inconel 625 were found to be more susceptible to corrosion as compared to 304L.
Date: January 1, 1991
Creator: Chandler, G.T. & Anderson, M.H.
Partner: UNT Libraries Government Documents Department

Evaluation of remote smearing of DWPF canistered waste forms

Description: The Savannah River Site (SRS) is evaluating the variables of the remote smearing process for monitoring transferable contamination on the waste glass canisters at the Defense Waste Processing Facility (DWPF). Smearing for transferable contamination is typically done by hand, but in this case, due to the nature of the high level waste within the canisters, remote smearing is required. The effectiveness of the smear pad was determined under varying conditions (distance traveled, force applied, and canister surface), as well as the relative importance of these factors. It was concluded that the remote smear is more reliable than the hand smear.
Date: January 1, 1991
Creator: Payne, C.H. & Rankin, W.N.
Partner: UNT Libraries Government Documents Department

Identification of colloids in nuclear waste glass reactions

Description: Characterization data for particulates formed under a variety of laboratory leaching conditions that simulate glass reaction in a repository environment are presented. Data on the particle size distributions and filterable fractions for neptunium, plutonium, americium, and curium were obtained by filtrations through a series of filters with pore sizes ranging from 1 {mu}m to 3.8 nm. The neptunium was found to be largely nonfilterable. Americium and plutonium were associated with filterable particles. The particles with which the americium, plutonium, and curium were associated were characterized using transmission electron microscopy (TEM) examination techniques. 8 refs., 1 fig., 2 tabs.
Date: January 1, 1991
Creator: Cunnane, J.C. & Bates, J.K.
Partner: UNT Libraries Government Documents Department

The effects of tritium and decay helium on the fracture toughness properties of stainless steels

Description: J-integral fracture mechanics techniques and scanning electron microscopy observations were used to investigate the effects of tritium and its decay product, helium-3, on Types 304L, 316L, 21-6-9, A286, and JBK-75 (Modified A286) stainless steels. Tritium-exposed samples of each steel had lower fracture toughness values and less resistance to stable crack growth than control samples. Type 316L stainless steel was more resistant to the embrittling effects of tritium and decay helium than the other steels.
Date: January 1, 1991
Creator: Morgan, M.J.
Partner: UNT Libraries Government Documents Department