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METALLURGY DIVISION QUARTERLY PROGRESS REPORT FOR PERIOD ENDING OCTOBER 31, 1950

Description: Minor changes in materials and methods resulted in increased yields in the production of fuel elements for the Bulk Shielding Facility. Attempts to bond uranium to a mercury-- silver alloy resulted in bonds of insufficient strength. Thorium alloys containing 2 to 4% Nb. Cr. Mn, Ti, Zr, Be. Al, and Si were prepared. The alloys containing Be, Al. or Si were hard, brittle, and not cold-workable. The alloys containing the other elements were coldworkable in the as-cast condition. Impact testing of pure thorium, using standard V-notch specimens, revealed a transition from brittle to tough behavior at 120 to 200 deg C. The determination of UAL/sub 4/: UAL/sub 3/ ratios, lattice parameters, and microstructures for the Al--Si--U system is reported. It was found that for a 20% uranium alloy, only 0.8% Si is necessary to completely suppress the formation of UAL/sub 4/. In general, ferritic iron--chromium alloys appeared more resistant to static corrosion by 1000 deg C lithium and lead than did austenitic alloys. Compatability tests with combinations of Mo, UO/sub 2/ BeO, Nb, and stainless steels 309 and 316 are discussed. True stress-natural strain-time diagrams for copper at room temperature are presented. (See also ORNL-2839.) (C.J.G.)
Date: February 1, 1951
Creator: Miller, E.C. & Bridges, W.H. eds.
Partner: UNT Libraries Government Documents Department

Hydrides and Metal-Hydrogen Systems. Final Report

Description: The work reported deals with the preparation and physical properties, especially thermal dissociation pressures, and densities of hydrides, hydrogen- metal systems, and mixtures of hydrides with other substances. Possible applicatlons as moderators, high-temperature neutron shields, and low-temperature shields are cited and design problems discussed. Most of the data on dissociation pressures cover ranges and compounds not hltherto explored because of experimental difficulties and the basic knowledge of the thermal behavior of hydrides was substantially increased. New hydrldes were prepared and several reported in the literature were shown not to exist. The following compounds, mixtures, and systems were studled: Tl-H, U-H, Ll-H, Na-H, Ca-H, Ba-H, Th-H, Sr- H; NaH-NaF, NaH-NaOH, NaH-CaH/, LlH-LiF, CaH/sub 2/-CaF/sub 2/, CaH/sub 2/-CaC/ sub 2/,CaH/sub 2/-Ca/sub 3/N/sub 2/; FeH/sub 3/ (alleged), NiH/sub 2/ (alleged), Ti(BH/sub 4/)/sub 3/, Th(BH/sub 4/)/sub 4/, WH/sub 4/ (attempted), W(BH/sub 4/)/ sub 4/ (attempted), /sub 4/NBH/sub 4/, (CH , and ydrides are ing an N/sub H/ comparable to water yet stable at red heat, compounds giving a neutron shield weight less than half that of water, and compounds suitable for use as hightemperature moderators containing large amounts of hydrogen. (auth)
Date: April 30, 1951
Creator: Gibb, T. R. P., Jr.
Partner: UNT Libraries Government Documents Department

The Uranium-Titanium Alloy System

Description: Abstract: "A uranium-titanium constitution diagram is presented. There is complete solid solubility between titanium and gamma uranium above about 2100 F. Only one compound exists in the system. It has a hexagonal structure based on U2Ti. It has a fairly wide range of stability, particularly on the titanium side. Beta-titanium solid solution decomposes eutectoidally into alpha titanium and compound at 1150 F. Eutectoid composition is about 72 atomic per cent titanium. Gamma-uranium solid solution decomposes eutectoidally at 1325 F into beta uranium and compound. Eutectoid composition is about 6 atomic per cent titanium. Beta uranium and compound react peritectoidally at 1233 F to give alpha uranium. Solubility of titanium in alpha and beta uranium is low as is the solubility or uranium in alpha titanium."
Date: November 5, 1952
Creator: Udy, Murray C. & Boulger, Francis W.
Partner: UNT Libraries Government Documents Department

Application of the Ewing Equation for Calculating Thermal Conductivity From Electrical Conductivity

Description: The usefulness of the Ewing equation for calculating the thermal conductivity of reactor metals and alloys from electrical resistance, specific heat, density, and atomic weight was investigated. The alloys investigated were Zircaloy-2, HSZA, Nb- 5.5 wt% V, Inconel, 18-8 stainless steel, and eutectic NaK. The Ewing equation was found to give calculated values with a degree of confidence similar to that of actual measured values. (auth)
Date: April 7, 1953
Creator: Powers, A. E.
Partner: UNT Libraries Government Documents Department

CORROSION OF URANIUM ALLOYS IN HIGH-TEMPERATURE WATER

Description: In the search for a corrosion-resistant high-uraniumcontent alloy for use as core material in high-temperature-water-moderated reactors, the corrosion of binary and ternary U alloys was studied in water at 500 and 600 deg F. Alloys contaiiifng less than 40 wt,% Zr additions completely oxidized upon short exposure at 600 deg F, whereas 50 plus wt.% alloys exhibited relatively low corrosion rates. Alloys were sensitive to heat treatment and were most resistant in the quenched condition. The corrosion rates of Zr alloys were linear to slightly accelerated with respect to time. Alloys containing 40, 50, and 60 wt.% Zr were resistant to water at 500 deg F. Molybdenum additions (arc-melted alloys) in the range of 10 to 15 wt.% improved the resistance of U to 600 deg F water but did not result in corrosion-resistant alloys, probably because of inhomogeneity of the alloys studied. The addition of Mo, Nb,Th, Sn, and Ti to uranium--20 wt.% zirconium resulted in several promising alloys: uranium--20 zirconium--5 molybdenum and uranium--20 zirconium-10 niobium. Additions of up to 5 wt,% Mo did not improve the resistance of 40 and 50% Zr alloys to 600 deg F water. A uranium--30 zirconium--5.6 tantalum alloy also exhibited promising resistance to 600 deg F water. Other additions (2 and 5 at.%) which did not improve the resistance of uranium--30 wt.% zirconium were: Sb, Bi, Cc, Cr, Co, Fe, Pb, Ni, Nb, Si, Th, Ti, and W. (auth)
Date: October 1, 1953
Creator: Pray, H.A. & Berry, W.E.
Partner: UNT Libraries Government Documents Department