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in subjects: "Actinide Alloys"

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Modeling of the phase evolution in Mg1-xAlxB2 (0<x<0.5) and its experimental signatures

Despite the chemical and structural simplicity of MgB{sub 2}, at 39 K this compound has the highest known {Tc} of any binary compound. Electron doping by substituting Al for Mg leads to decreasing Tc and the observed concentration dependent rate of decrease has been proposed to arise from the non-ideal character of MgB{sub 2}-AIB{sub 2} solid solutions, which derives from the existence of an ordered Mg{sub 0.5}Al{sub 0.5}B{sub 2} compound. Heterogeneous nano-scale structure patterns in solid so… more

Date: January 1, 2009

Creator: Andersson, Anders David; Casillas, Luis; Lezama Pacheco, Juan & Conradson, Steven D

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Characterization of Tank 48H Samples for Alpha Activity and Actinide Isotopics

This document reports the total alpha activity and actinide isotopic results for samples taken from Tank 48H prior to the addition of sodium tetraphenylborate and MST in Batch {number_sign}1 of the ITP process. This information used to determine the quantity of MST for Batch {number_sign}1 of the ITP process and the total actinide content in the tank for dose calculations.

Date: December 4, 1995

Creator: Hobbs, D. T.; Coleman, C. J. & Hay, M. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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THERMOSTATICS AND KINETICS OF TRANSFORMATIONS IN PU-BASED ALLOYS

CALPHAD assessment of the thermodynamic properties of a series of Pu-based alloys is briefly presented together with some results on the kinetics of phase formation and transformations in Pu-Ga alloys.

Date: June 30, 2006

Creator: Turchi, P; Kaufman, L & Liu, Z

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Evaluation of two styles of slotted, flat-head screws. [U--6% Nb alloys]

A series of torque tests were performed to evaluate the relative merits of two different flat-head screws fabricated from a uranium--6% niobium alloy. The screws tested were machined with both normal, straight-through slots in the head and with slots having radiused bottoms. Test results indicate that both designs easily surpass the required 20-inch-pound-proof torque.

Date: April 30, 1979

Creator: Reeves, C. A., Jr. & Johnson, W. B.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Preparation, heat treatment, and mechanical properties of the uranium-5 weight percent chromium eutectic alloy

The eutectic alloy of uranium-5 wt % chromium (U-5Cr) was prepared from high-purity materials and cast into 1-in.-thick ingots. This material was given several simple heat treatments, the mechanical properties of these heat-treated samples were determined; and the microstructure was examined. Some data on the melting point and transformation temperatures were obtained.

Date: October 1, 1980

Creator: Townsend, A. B.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Characterization of transuranium actinide alloy phase diagrams

Alloys of Np have been studied less than those,of the neighboring elements, U and Pu; the higher actinides have received even less attention. Recent interest in {sup 237}Np, {sup 241}Am and other actinide isotopes as significant, long-lived and highly radiotoxic nuclear waste components, and particularly the roles of metallic materials new handling/separations and remediation technologies, demands that this paucity of information concerning alloy behaviors be addressed. An additional interest i… more

Date: May 2, 1994

Creator: Gibson, J. K.; Haire, R. G.; Gensini, M. M. & Ogawa, T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Structural and magnetic characterization of actinide materials

This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The authors have successfully used neutron scattering techniques to investigate physicochemical properties of elements, compounds, and alloys of the light actinides. The focus of this work is to extend the fundamental research capability and to address questions of practical importance to stockpile integrity and long-term storage of nuclear material. Sp… more

Date: December 31, 1998

Creator: Cort, B.; Allen, T. H. & Lawson, A. C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Potentiometric determination of percent porosity in nickel electroplates on uranium metal

A potentiometric procedure has been developed to determine the percent porosity of nickel electroplates on uranium metal. In this case, percent porosity is defined as the ratio of the exposed uranium surface to the nickel electroplate surface times 100. Basically, this procedure exploits the high chemical reactivity between uranium metal and chloride ions in aqueous solution. It involves the potentiometric measurement of the corrosion potentials of coupled uranium/nickel metal electrodes in 0.0… more

Date: January 1, 1982

Creator: Dietrich, W.C. & Johnson, E.E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Anomalous vomume expansion of plutonium alloys

A simple heuristic model for the valence of Pu in its various phases is used to explain the large positive deviations from Vegard's Law in ..cap alpha..-Pu(Al), ..cap alpha..-Pu(Ti), and delta-Pu(Sc).

Date: January 1, 1981

Creator: Fisk, Z.; Elliott, R.O.; Tate, R.E. & Roof, R.B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Magnetic properties and electronic structure of the actinide systems UAl/sub 2/, NpAl/sub 2/, and PuAl/sub 2/

The electronic ground states of UAl/sub 2/, NpAl/sub 2/ and PuAl/sub 2/ have been determined by band theory techniques. These calculations indicate that both actinide d-f hybridization and spin-orbit coupling are important in these systems. Using a new scheme for obtaining the paramagnon parameters for UAl/sub 2/ it is shown that calculated and experimentally derived 5f band width are consistent. The fact that orbital angular momentum may not be quenched in these systems is suggested as a possi… more

Date: January 1, 1985

Creator: Albers, R. C.; Boring, A. M. & Koelling, D. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Stress-corrosion cracking of a uranium 6-weight percent niobium alloy

The stress-corrosion cracking (SCC) behavior of U--6 wt percent Nb in three different heat-treated conditions was investigated. The three heat treatments were: (a) solution quenched (the nonaged condition); (b) solution quenched and aged 6 hours at 250/sup 0/C (the underaged condition); and (c) solution quenched and aged 80 minutes at 600/sup 0/C (the overaged condition). The SCC tests utilized smooth, dead-weight loaded, static tensile specimens exposed to nitrogen-saturated or oxygen-saturate… more

Date: May 29, 1976

Creator: Kochen, R. L.; Mah, R. & Jackson, R. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Band description of materials with localizing orbitals

Density functional theory is a form of many-body theory which maps the problem onto an equivalent single particle-like system by limiting to the ground state (or some limited ensemble). So it should be surprising that this ground state theory could have any relevance whatsoever to the excitation properties of a material - and yet it does when used carefully. However, the most interesting materials involve active orbitals which are at least partially localized in space and this has profound effe… more

Date: March 1, 1986

Creator: Koelling, D.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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High-strength uranium-0. 8 weight percent titanium alloy penetrators

Long-rod kinetic-energy penetrators, produced from a uranium-0.8 titanium (U-0.8 Ti) alloy, are normally water quenched from the gamma phase (approximately 800/sup 0/C) and aged to the desired hardness and strength levels. High cooling rates from 800/sup 0/C in U-0.8 Ti alloy cylindrical bodies larger than about 13 mm in diameter cause internal voids, while slower rates of cooling can produce material that is unresponsive to aging. For the present study, elimination of quenching voids was of pa… more

Date: September 1978

Creator: Northcutt, W. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Electrical resistivity of U/sub 1/minus/x/M/sub x/Be/sub 13/ under pressure

Measurements of the electrical resistivity of U/sub 1/minus/x/ Th/sub x/ Be/sub 13/ compounds as a function of pressure provide a possible explanation for the unusual behavior of these materials. 10 refs., 2 figs.

Date: January 1, 1988

Creator: Borges, H. A.; Thompson, J. D.; Aronson, M. C.; Fisk, Z. & Smith, J. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Density-Functional Study of Magnetism in''Delta-Pu'' and its Alloys

At atmospheric pressure plutonium metal exhibits six crystal structures upon heating from room temperature to its melting point of 913 K. Among these phases, the {delta}-Pu has received a significant interest in the metallurgical community because of its high ductility that makes it easy to machine and form. The pure Pu {delta} phase is stable at elevated temperatures, between 593 K and 736 K, however a small amount of so-called {delta} stabilizer, for example, Al, Ga, Zn, Cd, Zr, SC, Am, Ce, I… more

Date: September 30, 2002

Creator: Landa, A & Soderlind, P

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Corrosion Testing of the General Electric-MANTECH II GAU 8/A Penetrator

A series of 8-inch artillery projectiles featuring mass properties variation were fired to determine the effect on crossrange deflection (drift). The results of this experimental program are presented. The drift of a spinning projectile away from the vertical plane of the firing azimuth is primarily caused by the yaw of repose. Analytic expressions for the repose angle and the crossrange deflection or drift have been developed by several authors. Previous analytical work showed that the drift o… more

Date: May 1, 1978

Creator: Johnson, H. R. & Weirick, L. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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X-ray diffraction study of reversible deformation mechanisms in the aged uranium-6. 5 niobium alloy

The x-ray diffraction (XRD) data from 200/sup 0/C/2h-aged uranium-6.5 wt % niobium (U-6.5Nb) alloys, taken under stress as a function of strain, revealed a gamma-zero (..gamma../sup 0/)..-->.. alpha prime-prime (..cap alpha..'') thermoelastic martensitic phase transformation. It was concluded that the primary reversible deformation modes consisted of the movement of ..gamma../sup 0//..cap alpha..'' interphase interfaces and ..cap alpha..'' intervariant interfaces. Specimen elasticity at low str… more

Date: June 21, 1985

Creator: Carpenter, D.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Low enrichment fuel development at INEL

SPERT IV, where a facility has been established for making low-enriched uranium aluminide mini-plates, is located near the Power Burst Facility. SPERT is an acronym for Special Power Excursion Reactor Test. A part of this former reactor facility has been converted into a fuel fabrication laboratory facility. The floor plan for the SPERT IV facility is shown. The reactor tanks are still in place, but they are due to be removed during December. The fuel fabrication laboratory and operations are d… more

Date: January 1, 1979

Creator: Newton, D.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Thermal Simulation of Quenching Uranium-0. 75% Titanium Alloy in Water

A computer model, The Quench Simulator, has been developed to simulate and predict in detail the behavior of U-0.75 Ti alloy when quenched at high temperature (about 850/sup 0/C) in cold water. The code allows one to determine the time- and space-dependent distributions of temperature, residual stress, distortion, and microstructure that evolve during the quenching process. The nonlinear temperature- and microstructure-dependent properties, as well as the cooling rate-dependent heats of transfo… more

Date: January 1, 1985

Creator: Siman-Tov, M.; Llewellyn, G. H.; Childs, K. W.; Ludtka, G. M. & Aramayo, G. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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X-ray diffraction studies of binary plutonium. Uranium alloys: an interim report

This report describes x-ray diffraction studies of Pu-U alloys carried on at LLNL in 1972. These studies were part of a larger project to understand the 2-phase, banded microstructures observed in Pu-15 wt% U alloys by Riefenberg and Ellinger. This work has produced relatively high-quality diffraction patterns for both components of the banded structures, but computer indexing of these patterns did not produce acceptable solutions for either the zeta-phase or the second component of the banded … more

Date: December 15, 1980

Creator: Wallace, P.L. & Harvey, M.R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Fabrication and characterization of uranium-6--niobium alloy plate with improved homogeneity

Chemical inhomogeneities produced during arc melting of uranium--6 weight percent niobium alloy normally persist during fabrication of the ingot to a finished product. An investigation was directed toward producing a more homogeneous product (approx. 13.0-mm plate) by a combination of mechanical working and homogenization. Ingots were cast, forged to various reductions, homogenized under different conditions, and finally rolled to 13.0-mm-thick plate. It was concluded that increased forging red… more

Date: October 31, 1978

Creator: Snyder, W.B.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Fabrication of a large plutonium sphere for use in LLL pulsed-sphere experiments. [Pu--1. 0% Ga alloy]

Two plutonium-alloy hemispheres were cast, machined, and canned for use in pulsed-sphere experiments. LLL physicists will use the data from these experiments to improve physics codes. The total mass of Pu--1.0 wt percent Ga was 9.3 kg. The hemispherical shapes had a radius of 53.7 mm. Both hemispheres were cast with hollow polar cones. In one casting the cone was plugged; in the other casting the cone was left to allow fitting to the neutron generator. The hemispheres were electron beam welded … more

Date: June 17, 1977

Creator: Rose, R. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Characterization of the uranium--2 weight percent molybdenum alloy. [Treatment to obtain 930 MPa yield strength (0. 2 percent)]

The uranium-2 wt percent molybdenum alloy was prepared, processed, and age hardened to meet a minimum 930-MPa yield strength (0.2 percent) with a minimum of 10 percent elongation. These mechanical properties were obtained with a carbon level up to 300 ppM in the alloy. The tensile-test ductility is lowered by the humidity of the laboratory atmosphere. (auth)

Date: May 19, 1976

Creator: Hemperly, V. C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Application of transmission electron microscopy to splat-cooled plutonium alloys

Plutonium alloy foils, thin enough for transmission electron microscopy (TEM), were made by rapidly quenching small specimens from the melt in a ''gun''-type, splat-cooling device. Microstructures in selected regions of the nonequilibrium alloys thus produced are illustrated and discussed. (auth)

Date: February 1, 1976

Creator: Rohr, D. L. & Elliott, R. O.

Item Type: Report

Partner: UNT Libraries Government Documents Department