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PROGRESS ON THE USE OF GAS-PRESSURE BONDING FOR FABRICATING LOW-COST CERAMIC, CERMET, AND DISPERSION FUELS. PHASE II REPORT ON AEC FUEL-CYCLE PROGRAM

Description: Uranium dioxide clad with Type 304 stainless steel was fabricated into rod, tubular, and flat-plate shapes by the gas pressure-bending process. Modifications of these basic designs included compartmented rods, corrugrted rods, and compartmented plates. The cold-compacting behavior in methods other than direct cold pressing and the pressurebonding behavior of seven commercial oxides and various mixtures were defined. Through the selection of initial oxides and compacting procedures, final oxide densities of 86 to 99.5% of theoretical were achieved. It was noted that the oxides tend to approach stoichiometry during the pressure-bonding process. Permeability measurements of high-density pressure-bonded uranium dioxide resulted in values that were within the blank rate of measuring apparatus, indicating equivalence to high-density sintering oxides. Thermal-conductivity measurements on similar materials also are consistent with high-density oxide as prepared by pressing and sintering. Of the oxides investigated, mixtures of ceramic and fused oxides appear to offer the most promise of achieving low-cost fuel elements through the pressure-bonding process. Such mixtures containing from 30 to 60 wt.% ceramic oxide provide a high initial pressed density and also permit achieving a high final density. Both oxides are low-cost materials. The preparation and pressure bending of uranium dioxidestainless steel cermets were also briefly studied. Materials of densities up to 96.5% of theoretical were obtained. Modulus-of-rupture and thermal-conductivity measurements also were obtained on these materials. (auth)
Date: November 1, 1960
Creator: Paprocki, S.J. ed.
Partner: UNT Libraries Government Documents Department

ARMY GAS-COOLED REACTOR SYSTEMS PROGRAM SUMMARY REPORT ON MATERIALS FOR THE GCRE-II

Description: Investigatiors were made of various materials for development of metal- canned and semi-homogeneous GCRE-II fuel element concepts. The materials were studied for application to development of fuels, grapanite, silicon-silicon carbide coatings, metal claddings, carburization barrier coatings, and graphite joining. A survey of the literature showad that uranium carbide fuels are superior to other types for the applications described and that refractory metal or metal carbide fuel coatings appear superior to other types for use with the types of graphite investigated. Experimental measurements were made of the thermal conductivity, tensile strength, stress-strain reiationships, and thermal expansion of graphite powdsr bonded with baked carbon at a final firing temperature of 760 deg C. Results showed that these materials were stronger and more isotropic at all test temperatures than a standard structure graphite such as ATJ. The thermal conductivity is somewhat lower and the thermal extansion slightly higher than the corresponding properties of ATJ. A silicon-silicon carbide coating was developed as an osidation-resistant coating for graphite. Preliminary air oxidation tests at 1000 deg C showed that the first samples survived 2000 hr with 10% failure. Subsequent experiments showed that it is reasonable to expect better performance in further tests. Tests for compatibility with graphite were conducted on zirconium, Zircaloy-2, "A" nickel, and K-Monel at 1750 and 1850 deg F for 1000 and 1500 hr. Chemical analyses, metallography, and tensile tests indicated that the K-Monel is the material most compatible with graphite; it possesses good strength and ductility with negligible carburization or carbon diffusion. Zircaloy-2 tubing showed a growth of from 3.4 to 3.8% when thermal cycled 100 times between 850 and 1850 deg F. Tests for compatibility with Hastelloy X were conducted on graphite samples coated with molybdenum, niobium carbide, and zirconium carbide at 1750 deg F and 300 psi for 1000 and ...
Date: December 30, 1960
Creator: Carpenter, R. & Del Grosso, A.
Partner: UNT Libraries Government Documents Department

THE UNSTABLE SPECIES AND THE ISOTOPE EFFECT IN THE PYROLYSIS OF DIBORANE IN A SHOCK TUBE

Description: From American Chemical Society 145th National Meeting, New York, Sept. 1963. The pyrolysis of diborane was examined using a chemical shock tube as a reactor. Additional evidence for the existence of hexaborane-12 and heptaborane- 11 and -13 was obtained. The presence of a large net normal isotope effect in the formation of tetraborane and hexaborane and a net inverse isotope effect in the formation of pentaborane-9 are observed. A mechanism, consisting of a series of competitive reactions and eqailibria, in which tetraboraue is the precursor of pentaborane-11 and hexaborane but not of pentaborane-9 is shown to be compatible with the observed isotope effect. Data obtained by examining the pyrolysis of various mixtures of boron hydrides are also consistent with the mechanism. (auth)
Date: January 1, 1963
Creator: Fehlher, T P & Koski, W S
Partner: UNT Libraries Government Documents Department

ENVIRONMENTAL RADIOACTIVITY AT ARGONNE NATIONAL LABORATORY. Report for the Year 1959

Description: The results of the environmental monitoring program at Argonne National Laboratory for 1959 are given. The radioactive content of the environment was measured by performing radiochemical analyses and total activity measurements on several types of materials collected on the ANL site and from locations approximately 10, 25, and 100 miles from the Laboratory. The sampling locations are given in Part II. The average total activities in samples of water, material from the beds of lakes and streams (bottom silt), soil, and plants during 1959 are tabulated. For purposes of comparison, the results obtnined from 1952 through 1959 are included. Air-filter results are also tabulated. Fallout activity was present in most samples at all locations. The amount of fall-out was relatively high during the first part of the year, but decreased markedly during the latter half. By the end of the year the shorter-lived fission products from fall-out were at the lowest level since 1955. Airborne beta activity from fall-out decreased from a maximum of about 5 mu mu c/m/sup 3/ in April to less than 0.1 mu mu c/m/sup 3/ in December. The average for the year, about 2.3 mu mu c/m/sup 3/, was 25% less than for 1958, but approximately twice as high as the average from 1953 to 1957. The long-lived airborne alpha activity has not changed appreciably since 1953. Air-filter samples were collected both on the site and at four locations from 6 to 20 miles from the Laboratory. The activities were essentially the same both on and off the site, and no indication of activity originating at Argonne was found in the samples. (auth)
Date: January 1, 1961
Creator: Sedlet, J.
Partner: UNT Libraries Government Documents Department

ANALYTICAL CHEMISTRY DIVISION ANNUAL PROGRESS REPORT FOR PERIOD ENDING NOVEMBER 15, 1963

Description: Research and development progress is reported on analytical instrumentation, chemical analysis of advanced reactor fuels, analytical studies of molten-salt systems, special research problems, reactor projects, effects of radiation on analytical methods, x-ray and spectrochemical analyses, spectroscopy, optical and electron microscopy, nuclear and radiochemical analyses, inorganic preparations, organic preparations, and analytical development. Service analyses are also described. Separate abstracts were prepared for each topic. (M.C.G.)
Date: February 18, 1964
Partner: UNT Libraries Government Documents Department

TRANSURANIUM QUARTERLY PROGRESS REPORT FOR PERIOD ENDING AUGUST 31, 1963

Description: The development of processes to separate and purify the transuranium elements, process equipment development, HFIR target fabrication studies, design of the TRU Processing Plant, design and installation of development facilities, corrosion studies, and analytical research directed toward this program are reponted in 6 papers. Separate abstracts were prepared for each paper. (M.C.G.)
Date: March 1, 1964
Creator: Burch, W.D., comp.
Partner: UNT Libraries Government Documents Department

FUEL CYCLE COSTS FOR A PLUTONIUM RECYCLE SYSTEM

Description: The costs of the chemical and metallurgical steps in the fuel cycle for large desalination reactors are estimated. Both capital and operating costs are presented at varying plant capacities for a Zircaloy-clad fuel element containing depleted uranium and recycled plutonium as the oxides. UO/sup 2/-0.5% PuO/sub 2/. The chemical steps are reported at throughputs of 1, 10, and 30 short tons of uranium per day; and the metallurgical or fabrication step at throughputs of 1, 3, 5, and 10 tons per day, as specified by the Office of Science and Technology. The total estimated cost of all the chemical and metallurgical steps drops from .17 to .68 per kilogram of uranium as the cycle throughput is increased from 1 to 10 tons of uranium per day. All steps decrease in cost as plant capacity is increased, with the most impressive decrease in the irradiated assembly processing step, which decreases from .19 to 10 to 07 per kilogram of uranium as throughput is changed from 1 to 10 to 30 tons of uranium per day. The contained data in conjunction with previous studies of a natural uranium fuel cycle and results of a current reactor optimization study will yield complete fuel cycle costs and plutonium value in recycle. (auth)
Date: January 20, 1964
Creator: Harrington, F. E.; Arnold, E. D.; Brater, D. C.; Douglas, D. A.; Smiley, S. H.; Stockdale, W. G. et al.
Partner: UNT Libraries Government Documents Department

WATER CHEMISTRY AND FUEL ELEMENT SCALE IN EBWR

Description: The first two sections summarize investigations in EBWR concenced with some aspects of water chemistry. The results of many of these investigations have not been previously published in a form given wide distribution. Included are studies of water conditions, corrosion products (composition, activities, transportation, deposition, and distribution), water dissociation, water activity, fission-product release, and build-up of plant activity. The last two sections of the report give the results of studies of the heattansfer characteristics of fuel-element scale and effects of high-temperature heating on scale removal and fuelelement growth. The maximum scale thickness measured was about 0.008 in. Heat-transfer calculations based on scale thermal conductivity measurements indicate the possibility of maximum fuel temperatures as high at 1692/sup o/F at 100-Mw operation of the core. This temperature is in a range where fuel growth, with resulting fuel element distortion and damage, is expected. Observed trends that may alleviate damage are the tendency of scale to flake off in high-heat transfer areas and the restraining effect of cladding on growth of fuel. No satisfactory means has been found to descale the fuel plates. (auth)
Date: November 1, 1960
Creator: Breden, C.R.; Charak, I. & Leyse, R.H.
Partner: UNT Libraries Government Documents Department

ANNUAL REPORT, JULY 1, 1960

Description: Research facilities, general construction progress, research activities, and administration are discussed and a financial statement is given. Fairly detailed accounts are given of research programs in the fields of physics, accelerator development, instrumentation, applied mathematics, chemistry, nuclear engineering, biology, and medicine. (M.C.G.)
Date: October 31, 1961
Partner: UNT Libraries Government Documents Department

PROGRESS REPORT ON FUEL ELEMENT DEVELOPMENT AND ASSOCIATED PROJECTS

Description: ; 9 < 4 6 9 7 ; 6 8 7 6 sting Deactor (MTR) has sought to develop improved, economical, long-life fuel assemblies through a comprehensive study of various fuel compositions, enrichments, claddings, burnable poisons, fuel and poison distributions, and fuelelement geometry optimization. The core materials, including uranium -- aluminum alloys, uranium oxide -aluminum cermets, thorium, thorium oxide, boron, gadolinium, dysprosium, and iridium, are tested in pilot-plant scale by irradiating them as sandwich type sample fuel plates. In the procurement of these sample plates, fabrication techniques were developed and evaluated for incorporation of all the fuels and poisons (except Ir/sub 2/O/sub 3/) into cores of aluminum or aluminum alloys. Methods were developed to minimize "dog-boning" and to produce graded fuels. Some of the sample plate compcsitions have been irradiated to high burn-up, i.e., over 50% of the U/sup 235/ content, and have operated successfully in the MTR for seven or more cycles. The irradiated uranium-- aluminum alloy and uranium oxide-- aluminum cermet fuel plates have shown excellent dimensional stability and good corrosion resistance to long-term irradiation. However, some of the thorium oxide fuel plates failed during one cycle of irradiation because of blistering, rupturing, or forming of pinholes in the cladding. The isostatic bonding procedure used to bond aluminum plates to the ThO/sub 2/ cores is apparently not adequate for reactor use. The sample fuel plate work has demonstrated the suitability of high wt.% uranium oxide--aluminum fuels for testing reactors, indicated the potential of systematically varying the fuel loading within a single plate, and experimentally verified the applicability of burnable poisons for reducing reactivity changes resulting from fuel burnup. The Deactivity Measurement Facility has proved to be an excellent nondestructive analytical tool for determination of fuel and poison burn-up. This program has stimulated several new developments and revealed many ...
Date: August 16, 1960
Creator: Francis, W.C. & Craig, S.E. ed.
Partner: UNT Libraries Government Documents Department

THE RADIOCHEMISTRY OF POLONIUM

Description: A bibliography of eight general reviews on the chemistry of Po is presented. The characteristics of Po isotopes are tabulated. The oxidation states, compounds, complexes, and analytical chemistry of Po are reviewed. Radiochemical procedures for Po are presented. (D.L.C.)
Date: January 1, 1961
Creator: Figgins, P.E.
Partner: UNT Libraries Government Documents Department

THE PREPARATION OF PLUTONIUM(IV) AMMONIUM FLUORIDE AND ITS DECOMPOSITION TO PLUTONIUM TETRAFLUORIDE FOR SUBSEQUENT REDUCTION TO METAL

Description: An exothermic reaction was shown to take place between low temperature plutonium dioxide and ammonium bifluoride at 50 to 250 deg C, The reaction goes essentially to completion with the formation of the pink plutonium(IV) ammonium fluoride, This compound can be decomposed at 300 deg C and the resulting plutonium tetrafluoride dehydrated at 500 deg C. Analyses showed that plutonium tetrafluoride prepared in this manner is approximately 90% converted from the dioxide. On a twenty gram scale average reduction yields of over 97% can be obtained by reaction with metallic calcium in a hermetitally sealed, stationary bomb when a calcium-iodine booster is employed. (auth)
Date: March 16, 1954
Creator: Tolley, W.B.
Partner: UNT Libraries Government Documents Department

Gas-Cooled Reactor Project Quarterly Progress Report: June 1960

Description: Report documenting ongoing research and developments at the Oak Ridge National Laboratory's Gas-Cooled Reactor Project. Design Investigations: The effects on the power distribuestablished. A mathematical model was developed for studying shifting of the coolant stream as it moves along a rod in order to predict the temperatures of the parallel streams as they progress through the reactor. A fuelelement life code developed for computing the internal temperature structure, the amount of fission gas released, the internal pressure, the cladding strain when the internal pressure exceeds the coolant pressure, and the creep damage was used for comparing top-loading and inventedloading fuel programs for the EGCR. A statistical method was developed for estimating the probability that the hot spot on the EGCR fuel element will exceed a given temperature. A method of cooling the EGCR control rods was developed that will minimize diversion of coolant flow through leakage paths between graphite blocks. A preliminary design of a control rod cooled by this method was developed. Means for reducing the thermal stresses in the top head nozzles of the EGCR pressure vessel were studied. The stresses in the graphite sleeves of the EGCR fuel elements were calculated, and the maximum stress was found to be within the allowable limit. A study was made of the thermal stresses in the EGCR pressure-vessel support skirt, and a satisfactory design was developed. Procedures for removing ruthenium and cerium contamination from steel were outlined and incorporated in procedures for decontaminating the EGCR charge and service machines. Experimental information was obtained on the thermal characteristics of the specified EGCR fuel cluster. The effect of relative orientation of adjacent clusters on the heattransfer distribution in the downstream element was studied by means of mass-removal measurements on naphthalene-coated reds. Velocity distributions in the downstream element of two adjacent EGCR-type clusters ...
Date: August 22, 1960
Creator: Oak Ridge National Laboratory
Partner: UNT Libraries Government Documents Department

COMPARISON OF TWO COLORIMETRIC METHODS FOR URANIUM

Description: In order to establish the feasibility of using two colorimetric met;iods for the determination of uranium interchangeably, according to the interferences encountered in a particular sampte. results were obtained by each of the methods and compared. The dibenzoyl methane method and the ethyl acetate-ammonium thiocyanate procedure were compared on the basis of values secured on the same day. on different days, on an analysis of the variance. and on an analysis of the residual error for the methods on different days. On the basis of the findings of these tests. it is concluded that the two methods can be used interchangeably to determine the uranium content of the ethyl acetate extracts of samples. Since the interferences in the two methods are different. the uranium content of a variety of materials can be determined without additional separations being required. (auth)
Date: March 25, 1959
Creator: McCutchen, R.L.
Partner: UNT Libraries Government Documents Department

CHEMICAL ENGINEERING DIVISION SUMMARY REPORT FOR JANUARY, FEBRUARY, AND MARCH 1957

Description: Fluoride Volatilization Separations Process. Development of a fused fluoride process for dissolution of uranium-- zirconium fuel alloys continued. In corrosion tests to find a suitable container material, Ni was found to be susceptible to a sulfur-type attack. Hastelloy B showed promise, and graphite offers excellent chemical resistance but poor mechanical strength. The dissolution rate of Zr in NaF-- ZrF as affected by impingement of the HF sparge was studied. Production of UF/sub 6/ by fluidized bed fluorination of UF/sub 4/ from ore concentrates was studied. The preparation, melting point, vapor pressure, and vapor density of UF/sub 5/ are given. Preliminary dissolution and recovery runs in semi-works equipment are discussed. Fluidization. Fluidized- bed techniques have been applied to conversion of UO/sub 2/(NO/sub 3/)/sub 2/ to UF/sub 4/ and to calcination of radioactive liquid wastes. Activities of the Green Salt Pilot Plant and shakedown runs of the shielded waste calciner are described. Reactor Chemistry. Studies continued on the kinetics and mechanism of oxidation of U, Th, and Zr. Data are given for oxidation of U in oxygen from 125 to 295 tained C and 20 to 800 mm pressure, and for Zr from 400 to 900 tained C and 200 nan O/sub 2/ pressure. The ratio of capture to fission cross sections for U/sup 233/ and U/sup 238/ in EBR-I have been determined as a function of position. ChemicalMetallurgical Separations Processes. Development of pyrometullurgical processing of spent reactor fuels continued. Work is repcrted on: melt refining and casting of U--Pu; iodine volatility problem; the system U--B-- Ta; the distribution coefficients for Pu between U--Cr and Mg and U and Mg; extraction of Pu from U by liquid Mg; Ce removal by dross refining; adsorption of volatilized metuls on surface active materials; and fractional crystallization of U with Zn. Analytical Research. A study ...
Date: October 31, 1960
Partner: UNT Libraries Government Documents Department

PROGRESS RELATING TO CIVILIAN APPLICATIONS DURING FEBRUARY 1960

Description: Preliminary results from electrical studies indicate that the "valence- compensated", air-fired U/sub 3/O/sub 8/-La/sub 2/O/sub 3/ solid solutions containing greater than equimolar amounts of La/sub 2/O/sub 3/ are poor conductors. Progress is reported on work devoted to fabrication and evaluation of U/sub 3/O/sub 8/ solid solutions contairing 40. 50 and 60 mole% La/sub 2/O/ sub 3/. and a sample containing 25 mole% Y/sub 2/O/sub 3/ and MgO each. In an investigation on the effects of combined ultrahigh pressure and high temperature on the uranium-- oxygen system and on the reaction of the oxides with various mixed oxides, it was found that U/sub 3/O/sub 8/ has an oxygen-to-uranium ratio of UO/sub 2.7//sub 2/. Corrosion testing of niobium alloys in 600 and 680 deg F water and 750 deg F 1500-psi steam was continued, and results for exposure times ranging up to 308 days are tabulated. In development of niobium-- uranium fuels, corrosion test results were obtained in 224-day exposure to 600 deg F water and in 1500 deg F sedium for 500 hr. In investigations to improve the corrosion resistance and irradiation stability of thorium-- uranium alloys, tensile and creep tests were performed at 600 and 70O deg C. In general fuel element development, techniques were developed for sub-bonding of niobium. In urarium dioxide compaction studies, results of flash roasting to attain off-stoichiometry urarium dioxide powders are tabulated. Prooress is reported in the uranium carbide skull-casting process. in research on methods of preparing high-purity crystals of UO/sub 2/, success is reported by methods involving vapor deposition. The determination of iron by titration to a radiometric end point was found to be very sensitive to the concentration of the tartaric acid complexing agent and sodium acetate buffer. Esters of the methacrylate group were studied to determine the relation of total radiation dose ...
Date: March 1, 1960
Creator: Dayton, R.W. & Tipton, C.R. Jr.
Partner: UNT Libraries Government Documents Department

DETERMINATION OF INTERSTITIAL SOLID-SOLUBILITY LIMIT IN TANTALUM AND IDENTIFICATION OF THE PRECIPITATE PHASES

Description: Solid-solubility limits at 1500, 1000, snd 500/sup o/C for carbon, nitrogen, and oxygen in high-punity tantalum were determined by x-ray lattice- parameter methods. For carbon, the solubility was found to be 0.17 at. % at 1500/sup o/C and less than 0.07 at. % at l00/sup o/C. A nitrogen solubility of 3.70 at. % at l500/sup o/C decreased linearly with temperature to 2.75 at. % at 1000/sup o/C and 1.8 at. % at 500/sup o/C. In the case of oxygen, the solubility was found to be 3.65 at. % at 1500/sup o/C, 1.95 at. % at l0O0/sup o/ C, and 2.5 at. % at 500/sup o/C. The phases Ta/sub 2/, the lowtemperature modificstion of Ta/sub 2/O/sub 5/, and Ta/sub x/N of unknown coznposition hut which has a superlattice structure based upon the oniginsl body-centered-cubic tantalum lattice were identified is the initisl precipitates in the respective systems. (auth)
Date: October 28, 1960
Creator: Vaughan, D.A.; Stewart, O.M. & Schwartz, C.M.
Partner: UNT Libraries Government Documents Department

DEVELOPMENT OF CONTAINER MATERIALS FOR LAMPRE APPLICATIONS

Description: Some 53 high-purity binary tantalum-base alloys were prepared and evaluated as candidate materials of construc tion for the Los Alamos Molten Plutonium Reactor Experiment. Preliminary data indicate that good resistance to attack by the fuels can be obtained by alloying tantalum. Alloys containing additions of rhenium and tungsten showed good corrosion resistance in polythermal (1352 to 1022 deg F) tilting-furnace exposures. Tantalum--yttrium alloys also displayed good corrosion resistance, even though the yttrium apparently was lost during arc melting. Most of the alloys, including those which showed good corrosion resistance, were amenable to arc melting and casting and fabrication at room temperature. (auth)
Date: February 14, 1961
Creator: Drennen, D.C.; Langston, M.E.; Slunder, C.J.; Dunleavy, J.G. & Hall, A.M.
Partner: UNT Libraries Government Documents Department