Brine migration in salt and its implications in the geologic disposal of nuclear waste (open access)

Brine migration in salt and its implications in the geologic disposal of nuclear waste

This report respresents a comprehensive review and analysis of available information relating to brine migration in salt surrounding radioactive waste in a salt repository. The topics covered relate to (1) the characteristics of salt formations and waste packages pertinent to considerations of rates, amounts, and effects of brine migration, (2) experimental and theoretical information on brine migration, and (3) means of designing to minimize any adverse effects of brine migration. Flooding, brine pockets, and other topics were not considered, since these features will presumably be eliminated by appropriate site selection and repository design. 115 references.
Date: December 1, 1981
Creator: Jenks, G.H. & Claiborne, H.C.
Object Type: Report
System: The UNT Digital Library
Building-owners energy-education program. Final report (open access)

Building-owners energy-education program. Final report

The objectives of the program are to develop and test market a cogent education program aimed specifically at building owners to help them be more decisive and knowledgeable, and to motivate them to direct their managers and professionals to implement a rational plan for achieving energy conservation in their commercial office buildings and to establish a plan, sponsored by the Building Owners and Managers Association International (BOMA) to implement this educational program on a nation-wide basis. San Francisco, Chicago, and Atlanta were chosen for test marketing a model program. The procedure used in making the energy survey is described. Energy survey results of participating buildings in San Francisco, Chicago, and Atlanta are summarized. (MCW)
Date: December 1, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Calculated neutron-source spectra from selected irradiated PWR fuel assemblies (open access)

Calculated neutron-source spectra from selected irradiated PWR fuel assemblies

The energy spectra of neutrons emitted from a pressurized-water-reactor fuel assembly have been calculated for a variety of exposures and cooling times. They are presented in graphical form. Some effects of initial enrichment are also included. Neutrons from spontaneous fissions were given either a Maxwellian temperature of 1.2 or 1.5 MeV, depending on whether they were due to plutonium and uranium nuclides or curium nuclides. A single (..cap alpha..,n) spectrum was deemed sufficient to represent the neutrons from all the alpha-emitting nuclides. The proportions of the nuclides undergoing spontaneous fission and those emitting alpha particles were determined from calculated atom densities. The particular pressurized-water-reactor fuel assembly assumed for this purpose was of the type used in the H.B. Robinson Unit-2 power plant (740 MWe).
Date: December 1, 1981
Creator: Rinard, P. M.; Bosler, G. E. & Phillips, J. R.
Object Type: Report
System: The UNT Digital Library
Characterization of TMI-type wastes and solid products. Quarterly progress report, April-September 1981 (open access)

Characterization of TMI-type wastes and solid products. Quarterly progress report, April-September 1981

A research program is under way to systematically characterize the type of radwastes which may be generated in cleanup procedures following off-normal reactor operations. Specifically, the program is presently investigating how the properties of wastes containing ion-exchange media may be modified by heavy doses of irradiation from sorbed radionuclides. Special effort is being devoted toward quantifying the effects of factors such as radiation dose rate, chemical loading on the ion exchangers, moisture content and composition of external media, etc., which may inflence the relation between laboratory test results and field performance. Initial irradation damage measurements have been carried out on organic cation resin IRN-77 in both hydrogen and sodium forms. Gamma irradiation of both of these materials produces water soluble acidic decomposition products; the acid product yields depend on the chemical loading and are lower for the sodium form.
Date: December 1, 1981
Creator: Weiss, A.J.
Object Type: Report
System: The UNT Digital Library
Charging-circuit study for copper-vapor lasers. Final report, 29 June 1981-30 November 1981 (open access)

Charging-circuit study for copper-vapor lasers. Final report, 29 June 1981-30 November 1981

This study is divided into three tasks whose combined purpose is to evaluate methods of charging high PRF pulsed power subsystems required in a proposed laser isotope separation (LIS) plant. The work performed in this program follows directly from designs and experiments carried out in a recently-completed study and, in fact, utilizes much of the same apparatus described previously. The first task required the preparation and vugraph presentation of a review of eight potential charging methods. This review and the associated evaluation criteria are described. Tasks II and III entailed the experimental evaluation of the deQing methods of regulating the charging voltage of a pulse power conditioning module with respect to limitations imposed by continuous operation and the efficiency of recovery of energy diverted by the deQing circuitry. The results of these tasks are described.
Date: December 1, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Charmed baryon decays observed in e/sup +/e/sup -/ annihilation at SPEAR (open access)

Charmed baryon decays observed in e/sup +/e/sup -/ annihilation at SPEAR

Various weak decays of the charmed baryon ..lambda../sub c/ are observed in the Mark II detector at the SLAC e/sup +/e/sup -/ storage ring SPEAR. Hadronic decays ..lambda../sub c//sup +/ ..-->.. pK/sup -/..pi../sup +/ and ..lambda../sub c//sup +/ ..-->.. pK/sub s//sup 0/ and their conjugates are observed as peaks in invariant mass spectra at m(..lambda../sub c/) = (2286 +- 6) MeV/c/sup 2/. An estimate of the charmed baryon production cross section, sigma(..lambda../sub c/) + sigma (anti ..lambda../sub c/) = (1.7 +- 0.4) nb, derived from Mark II measurements of the inclusive baryon cross sections R/sub p/ and R/sub ..lambda../ as functions of center-of-mass energy, is used to calculate branching ratios for these hadronic decays: BR (..lambda../sub c//sup +/ ..-->.. p K/sup -/ ..pi../sup +/) = (2.0 +- 0.8)%; BR (..lambda../sub c//sup +/ ..-->.. p k/sub s//sup 0/)/BR (..lambda../sub c//sup +/ ..-->.. p K/sup -/ ..pi../sup +/) = (36 +- 16)%. An attempt is also made to observe higher mass charmed baryons by reconstructing cascade decays ..sigma../sub c/ ..-->.. ..lambda../sub c/..pi... Evidence for the observation of semileptonic decays of the charmed baryon is presented. Direct electrons are observed in events containing antiprotons, lambdas and antilambdas. The number of electrons per baryon …
Date: December 1, 1981
Creator: Vella, E.N.
Object Type: Report
System: The UNT Digital Library
Chemicals identified in feral and food animals: a data base. First annual report, October 1981. Volume I. Records 1-532 (open access)

Chemicals identified in feral and food animals: a data base. First annual report, October 1981. Volume I. Records 1-532

This data file is a companion to Chemicals Identified in Human Biological Media, A Data Base, and follows basically the same format. The data base on human burden is in its third year of publication. This is the first annual report for the feral and food animal file. Data were obtained primarily from the open literature through manual searches (retrospective to 1979) of the journals listed in Appendix A. The data base now contains information on 60 different substances. Chemicals are listed by Chemical Abstracts Service (CAS) registry numbers and preferred names in Appendix B. For the user's convenience, cross-referenced chemical lists of CAS preferred and common names are provided in Appendix C. The animals, tissues, and body fluids found to be contaminated by these chemicals are listed in Appendix D. The data base is published annually in tabular format with indices and chemical listings that allow specific searching. A limited number of custom computer searches of the data base are available in special cases when the published format does not allow for retrieval of needed information.
Date: December 1, 1981
Creator: Cone, M. Virginia; Faust, Rosmarie A. & Baldauf, Margaret F. (comps.)
Object Type: Report
System: The UNT Digital Library
Chemicals identified in human biological media: a data base. Third annual report, October 1981 (open access)

Chemicals identified in human biological media: a data base. Third annual report, October 1981

Data from almost 1600 of the 3800 body-burden documents collected to date have been entered in the data base as of October 1981. The emphasis on including recent literature and significant research documents has resulted in a chronological mix of articles from 1974 to the present. When body-burden articles are identified, data are extracted and entered in the data base by chemical and tissue/body fluid. Each data entry comprises a single record (or line entry) and is assigned a record number. If a particular document deals with more than one chemical and/or tissue, there will be multiple records for that document. For example, a study of 5 chemicals in each of 3 tissues has 15 different records (or 15 line entries) in the data base with 15 record numbers. Record numbers are assigned consecutively throughout the entire data base and appear in the upper left corner of the first column for each record.
Date: December 1, 1981
Creator: Cone, M.V.; Baldauf, M.F. & Martin, F.M. (comps.)
Object Type: Report
System: The UNT Digital Library
Chemicals identified in human biological media: a data base. Third annual report, October 1981 (open access)

Chemicals identified in human biological media: a data base. Third annual report, October 1981

Part 2 contains the data base in tabular format. There are two sections, the first with records on nondrug substances, and the second with records on drugs. Chemicals in each section are arranged alphabetically by CAS preferred name, CAS registry number, formula, atomic weight, melting point, boiling point, and vapor pressure. Tissues are listed alphabetically with exposure route, analytical method, number of cases, range, and mean - when available in the source document. A variety of information may also be included that is pertinent to the range and mean as well as experimental design, demography, health effects, pathology, morphology, and toxicity. Review articles are included in the data base; however, no data have been extracted from such documents because the original research articles are included.
Date: December 1, 1981
Creator: Cone, M.V.; Baldauf, M.F. & Martin, F.M. (comps.)
Object Type: Report
System: The UNT Digital Library
Chemistry and morphology of coal liquefaction. Quarterly report, October 1-December 31, 1981 (open access)

Chemistry and morphology of coal liquefaction. Quarterly report, October 1-December 31, 1981

Progress reports are presented for the following six tasks: (1) selective synthesis of gasoline range components from synthesis gas; (2) electron microscopy studies of coal during hydrogenation; (3) catalysed low temperature hydrogenation of coal; (4) selctive hydrogenation, hydrogenolysis and alkylation of coal and coal liquids by organo-metallic systems; (5) chemistry of coal solubilization and liquefaction; (6) coal conversion catalysts-deactivation studies. Highlights are as follows: (1) In the presence of hydrogen and the absence of base, using the catalyst RuCl/sub 2/ (CO)/sub 2/ (phi/sub 3/ P)/sub 2/ excellent yields of reduced polynuclear heteroaromatic nitrogen compound were produced with 100% selectivity for the N-containing ring. (2) A careful gas chromatographic analysis of Fischer-Tropsch products has shown that major peaks, previously thought to be single compounds are composites of two or more compounds. Resolution of these peaks will enable one to establish a rational grouping of n/i and paraffin/olefin ratios. (3) Addition of iron or rhodium to potassium impregnated graphite did not result in the production of heavier hydrocarbons than methane from the graphite-steam reaction at low temperature. However, small amounts of iron enhanced the methane production. (ATT)
Date: December 1, 1981
Creator: Heinemann, H.
Object Type: Report
System: The UNT Digital Library
Coated particle waste form development (open access)

Coated particle waste form development

Coated particle waste forms have been developed as part of the multibarrier concept at Pacific Northwest Laboratory under the Alternative Waste Forms Program for the Department of Energy. Primary efforts were to coat simulated nuclear waste glass marbles and ceramic pellets with low-temperature pyrolytic carbon (LT-PyC) coatings via the process of chemical vapor deposition (CVD). Fluidized bed (FB) coaters, screw agitated coaters (SAC), and rotating tube coaters were used. Coating temperatures were reduced by using catalysts and plasma activation. In general, the LT-PyC coatings did not provide the expected high leach resistance as previously measured for carbon alone. The coatings were friable and often spalled off the substrate. A totally different concept, thermal spray coating, was investigated at PNL as an alternative to CVD coating. Flame spray, wire gun, and plasma gun systems were evaluated using glass, ceramic, and metallic coating materials. Metal plasma spray coatings (Al, Sn, Zn, Pb) provided a two to three orders-of-magnitude increase in chemical durability. Because the aluminum coatings were porous, the superior leach resistance must be due to either a chemical interaction or to a pH buffer effect. Because they are complex, coated waste form processes rank low in process feasibility. Of all the …
Date: December 1, 1981
Creator: Oma, K. H.; Buckwalter, C. Q. & Chick, L. A.
Object Type: Report
System: The UNT Digital Library
Comparative analysis of polycyclic aromatic sulfur heterocycles isolated from four shale oils. [Polycyclic aromatic sulfur heterocycles; thiophenes] (open access)

Comparative analysis of polycyclic aromatic sulfur heterocycles isolated from four shale oils. [Polycyclic aromatic sulfur heterocycles; thiophenes]

This report describes the isolation of sulfur heterocycle fractions from four shale oils (Paraho, Geokinetics, Occidental, and Rio Blanco), the use of capillary column gas chromatography and mass spectrometry for the identification of individual mixture components, and a reverse (Ames) and forward mutation assay with Salmonella typhimurium to screen for possible health hazards. The major components of the Polycyclic Aromatic Sulfur Heterocycles (PASH) fractions for all four shale oils were found to be two- to three-ringed parent and alkylated thiophene compounds. In all cases the PASH fractions showed no more specific mutagenic response than the neutral PAC fractions from which they were isolated. The only mutagenic response which was detected in the PASH fractions was for the Rio Blanco shale oil and showed specific mutagenic response similar to the neutral PAC fraction from which it was isolated. Finally, the forward mutation 8-azaguanine test was apparently more sensitive than the Ames histidine reversion test in detecting mutagenic activity for the chemical fractions from the shale oils.
Date: December 1, 1981
Creator: Willey, C.; Pelroy, R. & Stewart, D.
Object Type: Article
System: The UNT Digital Library
Comparison of computed reaction rates using different methods and data for the STARFIRE and TMHR benchmark blankets (open access)

Comparison of computed reaction rates using different methods and data for the STARFIRE and TMHR benchmark blankets

RAFFLE Monte Carlo calculations using ENDF/B V5 data have been performed for the TMHR suppressed fission benchmark blanket and the STARFIRE Reference Design blanket. One-dimensional cylindrical geometry was employed. ANISN S/sub N/ calculations were also done for both blankets using the DLC37F, FLUNG, and MACKLIB IV data sets. Reaction rates from RAFFLE and ANISN are compared with each other and with results obtained by the blanket designers (ANL, TRW, GA). The purposes of this study are to: (1) partially validate the new RAFFLE libraries for fusion neutronics and, (2) lend confidence to the results of previous ANISN calculations that were done to investigate the feasibility of fusion blanket testing in the Engineering Test Reactor. For both blankets, the tritium breeding ratio (TBR) predicted by RAFFLE and ANISN agree within 3%. For TMHR, our TBR results lie in between those obtained by TRW and GA, which disagree by 10 to 15%. For STARFIRE, our TBR results are 7 to 10% lower than ANL's values. The reason for the large discrepancies is unknown. However, it is concluded that modeling errors are unlikely so that data sources and processing differences used to generate cross section libraries are implied. Additional investigation is needed to …
Date: December 1, 1981
Creator: Scott, A.J. & Takata, M.L.
Object Type: Report
System: The UNT Digital Library
Comparison of techniques for preserving dissolved nutrients in open-ocean seawater samples (open access)

Comparison of techniques for preserving dissolved nutrients in open-ocean seawater samples

A survey of recent literature on methods for preserving nutrients indicates that the major factors which have been considered are: filtration and type of filter, material and history of storage containers, the influence of light, storage temperature and how it is achieved, the effectiveness of various acids, poisons, and preservatives, and the source of the sample. No comprehensive studies of open ocean seawater were found. A comprehensive study of nutrient preservation techniques was conducted on surface and deep seawater samples collected in the Gulf Stream east of Miami, Florida. No preservation techniques were found to be satisfactory for near-surface open ocean seawater. Results for deep water samples are found to be substantially better. The degree of preservation was not substantially improved by complex techniques involving freezing and chemical additives. Storage of filtered samples in aged polyethylene bottles at 2/sup 0/C in the dark is recommended for samples that must be stored. (LEW)
Date: December 1, 1981
Creator: Morse, J. W.; Hunt, M.; Zullig, J.; Mucci, A. & Mendez, T.
Object Type: Report
System: The UNT Digital Library
Compatibility of the Zr-Al alloy with a tokamak plasma environment (open access)

Compatibility of the Zr-Al alloy with a tokamak plasma environment

We have investigated the compatibility of the Zr-Al alloy bulk getter with a tokamak plasma environment, where the hydrogenic fluxes are sufficient to cause embrittlement in relatively short times. Under normal operating conditions with the getters activated, it is necessary to regenerate the absorbed hydrogenic species before the embrittlement limit is reached. We present a method for determining the loading under tokamak conditions where the Zr-Al surface characteristics can change. During glow discharge cleaning and pulse discharge cleaning, it is not convenient to regenerate. We find, however, that during the cleaning operations the getter self-inerts, thus limiting the loading. We present data and a model which accounts for this behavior in terms of impurity adsorption on the room temperature getter surface during the cleaning operations.
Date: December 1, 1981
Creator: Knize, R. J.; Cecchi, J. L. & Dylla, H. F.
Object Type: Report
System: The UNT Digital Library
Composite design of an advanced airborne monitoring system (open access)

Composite design of an advanced airborne monitoring system

Atmospheric chemistry investigations often require a multitude of measurements which can be obtained only through the utilization of airborne sampling platforms. Instrument limitations and the aircraft environment present several considerations for sampling-system design, including such factors as instrument sensitivities and response times, altitude effects, sampling intervals for acquiring samples, and physical compatibility with the aircraft. An aircraft system with an extensive evolutionary instrument array has been in development at PNL for several years during which several special systems have been developed to improve aircraft measurement capabilities. A high-volume air sampling system providing flows of up to 4 m/sup 3//min and simultaneous collection of three filters in parallel has been constructued to reduce filter collection times. A constant pressure inlet system was developed to overcome adverse effects in instrument response resulting from altitude changes. The system functions so that instruments which are connected experinece a constant pre-set pressure regardless of the sampling altitude. This system is particularly useful for airborne operation of a flame photometric sulfur analyzer. Special chemiluminescence NO/NO/sub x/ analyzers utilizing photon counting were built which are capable of fast response and detecton of concentrations in the sub-ppB range.
Date: December 1, 1981
Creator: Busness, Kenneth M.; Alkezweeny, Abdul J.; Easter, Richard C.; Hales, Jeremy M. & Lee, Richard N.
Object Type: Article
System: The UNT Digital Library
Comprehensive energy-management program. Hybrid photovoltaic/thermal absorber. Annual report, September 1, 1980-December 31, 1981 (open access)

Comprehensive energy-management program. Hybrid photovoltaic/thermal absorber. Annual report, September 1, 1980-December 31, 1981

Research work was done during the reporting period on the two-part research program: (A) to improve energy conservation through increased unit and system efficiencies, energy management, and system optimization, and (B) to develop a novel, low-cost hybrid photovoltaic/thermal absorber. Performance tests were conducted on all the boilers and chillers on campus. Several corrective measures were indicated and implemented. A detailed survey of energy use by functions and consumption/demand study has been in progress. A preliminary computer simulation model of the entire campus has been developed and made operational. It has been demonstrated both analytically and experimentally that the reradiation losses from the absorber can be reduced significantly by utilizing a light-pipe absorber. Two paraboloidal dishes, one of 6 ft diameter and the other of 20 ft diameter have been utilized. Collector efficiencies have been measured at coolant outlet temperatures up to 282/sup 0/C with a square light-pipe absorber and with 6 ft diameter concentrator. Laser ray testing was conducted on both the 6 ft and 20 ft diameter concentrators. Design of the total energy absorber has been completed.
Date: December 1, 1981
Creator: Kumar, G. N.; Sellers, J. P. & Dybczak, Z. W.
Object Type: Report
System: The UNT Digital Library
Computer-based test system for the Tactical Airfield Attack Munition (TAAM) safing, arming, and fuzing system (open access)

Computer-based test system for the Tactical Airfield Attack Munition (TAAM) safing, arming, and fuzing system

Testing and quality assurance of large numbers of firing systems are an essential part of the development of the Tactical Airfield Attack Munition (TAAM). A computerized test and data acquisition system has been developed to make the testing and quality assurance workload manageable. The system hardware utilizes an LSI-11/23 computer, a Tektronix 7612 transient digitizer, and various other programmable instruments and power supplies. The system is capable of measuring and analyzing mechanical shock and fireset transient waveforms, automating testing sequences, and making records and comparisons of the test results. The system architecture is flexible for general purpose firing system development work.
Date: December 1, 1981
Creator: Warhus, J.; Castleton, R. & Lanning, S.
Object Type: Article
System: The UNT Digital Library
Concepts of fundamental processes related to gasification of coal. Quarterly progress report, July-September 1981 (open access)

Concepts of fundamental processes related to gasification of coal. Quarterly progress report, July-September 1981

The research projects are described: (1) single stage catalytic coal gasification is an attractive concept as a direct method of producing high BTU gas from coal. This process involves the introduction of a coal-solvent slurry and hydrogen gas into a fixed bed catalytic reactor, which employs a catalyst high in hydrogenation and cracking activity. Steam may also be added to the system. The gas produced will be principally methane. Thermodynamic calculations indicate that this process is essentially autothermal. Since this process utilizes the heat of methanation to a maximum extent, significant overall energy savings can be achieved over the more conventional multi-stage gasification systems. The primary objective of this research is to optimize the process variables to maximize methane yields. Initially, a sulfided Ni-W/SiO/sub 2/-Al/sub 2/O/sub 3/ catalyst will be used; (2) the demand for molecular hydrogen and for synthesis gas is rapidly increasing. Therefore, an extensive program on steam reforming of aromatic compounds such as benzene, substituted benzenes, naphthalene and other aromatics found in coal and coal-derived liquids (CDL) is being carried out. The combination of coal liquefaction-steam reforming of CDL could prove to be an important alternative to coal gasification for the production of SNG and hydrogen. An …
Date: December 1, 1981
Creator: Wiser, W.H.
Object Type: Report
System: The UNT Digital Library
Consolidated fuel reprocessing program. Progress report, July 1-September 30, 1981 (open access)

Consolidated fuel reprocessing program. Progress report, July 1-September 30, 1981

Technical progress is reported in overview fashion in the following areas: process development, laboratory R and D, engineering research, engineering systems, integrated equipment test facility (IET) operations, and HTGR fuel reprocessing. (DLC)
Date: December 1, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Continuum modeling of two-phase flows (open access)

Continuum modeling of two-phase flows

Continuum modeling of two-phase flows can essentially be achieved in two ways. The first approach, the so-called continuum theory of mixtures, ignores the details of the flow occurring on the microscopic level, while the second one is the result of some averaging procedure. Although they both lead, as expected, to the same set of basic equations, they differ strongly in their spirit when closure equations have to be found. In the present report, we have attempted to give a brief critical review of both approaches, to compare them and to discuss some of the major difficulties which arise. It is shown that the application of the continuum theory of mixtures is, in most cases, questionable and that the only appropriate way of finding closure equations, besides correlating experimental results, consists in a useful investigation of the microscopic flow pattern associated with an adequate averaging technique.
Date: December 1, 1981
Creator: Bataille, J. & Kestin, J.
Object Type: Report
System: The UNT Digital Library
Copper laser diagnostics and kinetics support (open access)

Copper laser diagnostics and kinetics support

In the effort MSNW participated with the LINL copper-Vapor Laser Program by providing a useful plasma diagnostic for interpretation of Copper-vapor laser kinetics. MSNW developed and delivered a pulsed interferometric diagnostic package to LLNL. Moreover MSNW provided personal services at the request and direction of LLL in the implementation of the diagnostic and interpretation of the data.
Date: December 1, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Correlation of Acoustic Emission Generated During Uniform Biaxial Loading to Microstructural Sources in 7075-T651 Aluminum and 21Cr-6Ni-9Mn Stainless Steel. Final Report (open access)

Correlation of Acoustic Emission Generated During Uniform Biaxial Loading to Microstructural Sources in 7075-T651 Aluminum and 21Cr-6Ni-9Mn Stainless Steel. Final Report

This paper reports on the effect on acoustic emission (AE) of uniform biaxial loading of a thin-walled tube designed by Hamstad, Patterson and Mukherjee. The AE generated during biaxial loading of 7075-T651 aluminum and 21Cr-6Ni-9Mn stainless steel had several anomalous features relative to tensile generated AE. The biaxial AE data was of a much higher level and peaked at a lower strain than the uniaxial AE response. A particle cracking model was proposed in which inclusions with the largest projected surface area perpendicular to the principal axis of applied loading will crack before smaller inclusions, and the resulting energy released per AE will be proportional to the crack surface area. The inclusion contents were studied with respect to size, shape, density, hardness, and fracture/decohesion behavior. The inclusions in both 7075-T651 and 21-6-9 display the preferred cracking orientation predicted in the Hamstad, et al. model and are shown to be associated with the generated AE. However, other factors appear to contribute to the total AE responses. There is evidence that for 7075-T651 subjected to biaxial loading, a grain boundary-related mechanism becomes a significant source of AE in the latter stages of strain hardening. Also, for both materials, the complex applied load …
Date: December 1, 1981
Creator: Leon, E. & Mukherjee, A. K.
Object Type: Report
System: The UNT Digital Library
Creep properties of forged 2219 T6 aluminum alloy shell of general-purpose heat source-radioisotope thermoelectric generator (open access)

Creep properties of forged 2219 T6 aluminum alloy shell of general-purpose heat source-radioisotope thermoelectric generator

The shell (2219 T6 aluminum forging) of the General Purpose Heat Source-Radioisotope Thermoelectric Generator was designed to retain the generator under sufficient elastic stress to secure it during space flight. A major concern was the extent to which the elastic stress would relax by creep. To determine acceptability of the shell construction material, the following proof tests simulating service were performed: 600 h of testing at 270/sup 0/C under 24.1 MPa stress followed by 10,000 h of storage at 177/sup 0/C under 55.1 MPa, both on the ground; and 10,000 h of flight in space at 270/sup 0/C under 34.4 MPa stress. Additionally, systematic creep testing was performed at 177 and 260/sup 0/C to establish creep design curves. The creep tests performed at 177/sup 0/C revealed comparatively large amounts of primary creep followed by small amounts of secondary creep. The early creep is believed to be abetted by unstable substructures that are annealed out during testing at this temperature. The creep tests performed at 270/sup 0/C showed normal primary creep followed by large amounts of secondary creep. Duplicate proof tests simulating the ground exposure conditions gave results that were in good agreement. The proof test simulating space flight at 270/sup …
Date: December 1, 1981
Creator: Hammond, J.P.
Object Type: Report
System: The UNT Digital Library