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Equilibrium Dissociation Pressures of the Delta and Epsilon Phases in the Zirconium-Hydrogen System

Description: Abstract: Pressure-temperature isochores were obtained for zirconium-hydrogen alloys, spanning the H/Zr composition range of 1.430 to 1.910. The studies were confined to the temperature limits of 300 to 900ÂșC, and the pressure limits of 0.01 to 10.0 atm.
Date: May 31, 1964
Creator: Raymond, J. W.
Partner: UNT Libraries Government Documents Department

Deformation Microstructures and Creep Mechanisms in Advanced ZR-Based Cladding Under Biazal Loading

Description: Investigate creep behavior of Zr-based cladding tubes with attention to basic creep mechanisms and transitions in them at low stresses and/or temperatures and study the dislocation microstructures of deformed samples for correlation with the underlying micromechanism of creep
Date: August 11, 2008
Creator: Murty, K. Linga (KL)
Partner: UNT Libraries Government Documents Department

Study of Second Phase Particles and Fe content in Zr Alloys Using the Advanced Photon Source at Argonne

Description: We have conducted a study of second phase particles and matrix alloying element concentrations in zirconium alloys using synchrotron radiation from the Advanced Photon Source (APS) at Argonne National Laboratory. The high flux of synchrotron radiation delivered at the 2BM beamline compared to conventional x-ray generators, enables the detection of very small precipitate volume fractions. We detected the standard C14 hcp Zr(Cr,Fe)2 precipitates, (the stable second phase in Zircaloy-4) in the bulk material at a cumulative annealing parameter as low as 10-20 h, and we followed the kinetics of precipitation and growth as a function of the cumulative annealing parameter (CAP) in the range 10-22 (quench) to 10-16 h. In addition, the unique combination of spatial resolution and elemental sensitivity of the 2ID-D/E microbeam line at the Advanced Photon Source at Argonne (APS) allows study of the alloying element concentrations at ppm levels in an area as small as 0.2 mm. We used x-ray fluorescence induced by this sub-micron x-ray beam to determine the concentration of these alloying elements in the matrix as a function of alloy type and thermal history. We discuss these results and the potential of synchrotron radiation-based techniques for studying zirconium alloys.
Date: November 7, 2001
Creator: Motta, Arthur T.
Partner: UNT Libraries Government Documents Department


Description: The applicability of the centrifugal casting technique to the production of multiple castings of fuel pins of small diameter and of thin fuel plates was investigated. Fuel pins measuring 0.185 in. in diameter by 4 1/4 in. long of unalloyed uranium and of a uranium-2 wt.% zirconium alloy were cast successfully in batches of sixteen pins per melt. Sixteen different metals and alloys were used as mold materials. Smaller and longer fuel pins, 0.165 in. in diameter by 9 3/4 in. long, of similar compositions were cast successfully in brass and copper molds. Thirty-six pins of the same diameter and length were cast simultaneously in each casting run. Attempts to cast centrifugally thin uranium plates measuring 9 in. long by 2 in. wide by 0.04 in. thick proved to be only partially successful, but encouraging. These plates were cast into graphite molds at the rate of six plates per run. The maximum usable length of the unalloyed uranium plates cast did not exceed six inches. (auth)
Date: March 1, 1961
Creator: Yaggee, F.L.
Partner: UNT Libraries Government Documents Department

Review of the oxidation rate of zirconium alloys.

Description: The oxidation of zirconium alloys is one of the most studied processes in the nuclear industry. The purpose of this report is to provide in a concise form a review of the oxidation process of zirconium alloys in the moderate temperature regime. In the initial ''pre-transition'' phase, the surface oxide is dense and protective. After the oxide layer has grown to a thickness of 2 to 3 {micro}m's, the oxidation process enters the ''post-transition'' phase where the density of the layer decreases and becomes less protective. A compilation of relevant data suggests a single expression can be used to describe the post-transition oxidation rate of most zirconium alloys during exposure to oxygen, air, or water vapor. That expression is: Oxidation Rate = 13.9 g/(cm{sup 2}-s-atm{sup -1/6}) exp(-1.47 eV/kT) x P{sup 1/6} (atm{sup 1/6}).
Date: November 1, 2005
Creator: Causey, Rion A. (Sandia National Laboratories, Livermore, CA); Cowgill, Donald F. (Sandia National Laboratories, Livermore, CA) & Nilson, Robert H. (Sandia National Laboratories, Livermore, CA)
Partner: UNT Libraries Government Documents Department


Description: The current-carrying capacity of Nb- Zr wire was studied under conditions of swept magnetic field and fixed wire current and of fixed magnetic field and swept wire current. The effects of wire movement, thermal environment, copper coating of the wire, and rate of sweep of wire current or magnetic field were determined for these test conditions. (auth)
Date: January 1, 1963
Creator: Laverick, C
Partner: UNT Libraries Government Documents Department


Description: The effect of primary alpha present during the solutiontreating cycle on the incubation period for the decomposition of beta and on the resultant structure has been determined for Zr-base alloys containing from 7 to 15 wt.% U and from 0.094 to 0.29 wt.% 0. Prior-existing alpha decreased the time at which precipitation of Widmanstgtten alpha started and increased the rate of precipitation. The microstructure of transformed alloys was correlated with tentative isothermal-transformation diagrams. (auth)
Date: January 14, 1958
Creator: Douglass, D.L. & Marsh, L.L. Jr.
Partner: UNT Libraries Government Documents Department


Description: This report summarizes the series of irradiations conducted in a Hanford reactor on specimens of zirconiumclad, uranium-- zirconium fuel plates containing 3, 6, and 14 vt.% highly (93.4%) enriched uranium. More than thirty fuel plates were exposed during the test program, which extended over a period of several years. (auth)
Date: February 1, 1958
Creator: Bailey, R.E.
Partner: UNT Libraries Government Documents Department


Description: The interpretation of the dimensional instability of U- Zr alloy containing small amounts of boron has raised the question of whether the observed low-temperature swelling can be related to the temperatureswelling characteristics of either the U-Zr alloy or Zr- B alloys by themselves. To obtain such information on the Zr--B system to compare with the more detailed study of thc alloy early results of which were reported in KAPL-1562, pieces of previously irradiated Zr- B alloys and dispersions were annealed in vacuum at temperatures between 350 and 750 C. (auth)
Date: May 12, 1958
Creator: Johnston, W.V. & Noonan, J.E.
Partner: UNT Libraries Government Documents Department

Recoil Range of Fission Fragments in Zirconium

Description: The recoil ranges of fission fragruents in zirconium were measured by irradiating small pieces of a Zircaloy-2 ribbon containing 492 ppm of homogeneously dispersed U/sup 235/. The samples were wrapped in aluminum foil during the irradiation to catch the fission fragments escaping from the surface of the Zircaloy-2. Average values of 10.1 and 8.15 microns were obtained for the recoil ranges of the median light and heavy fission fragments, respectively; these values compare quite well with values calculated from empirical equations. (auth)
Date: November 1, 1959
Creator: Smith, E. R. & Frank, P. W.
Partner: UNT Libraries Government Documents Department

Mechanical properties of nanocrystalline metals, intermetalics and multiphase materials determined by tension, compression and disk-bend techniques

Description: The mechanical behavior of nanocrystalline metallic, intermetallic, and multiphase materials was investigated using tension, compression, and disk-bend techniques. Nanocrystalline NiAl, Al-Al{sub 3}Zr, and Cu were synthesized by gas condensation and either resistive or electron beam heating followed by high temperature vacuum compaction. Disk- bend tests of nanocrystalline NiAl show evidence of improved ductility at room temperature in this normally extremely brittle material. In contrast, tension tests of multiphase nanocrystalline Al- Al{sub 3}Zr samples show significant increases in strength by substantial reductions in ductility with decreasing grain size. Compression tests of nanocrystalline copper result in substantially higher yield stress and total elongation values than those measured in tensile tests. Implications for operative deformation mechanisms in these materials are discussed.
Date: February 1, 1997
Creator: Eastman, J.A.; Thompson, L.J.; DiMelfi, R.J.; Choudry, M.; Dollar, M.; Weertman, J.R. et al.
Partner: UNT Libraries Government Documents Department

Microhardness and elastic modulus of nanocrystalline Al-Zr

Description: An investigation of the mechanical properties of nanocrystalline Al-Zr alloy composites has been conducted via nanoindentation and Vickers microhardness experiments. The microhardness of the samples exhibits a four-fold increase over the concentration range of 0-30 wt.% Zr, from {approximately}0.7 GPa to nearly 3 GPa. The aluminum grain size is found to be strongly correlated with the level of zirconium present in the samples, suggesting that the observed hardness increase can be attributed to the combined effects of alloying and grain size reduction. The elastic moduli of the nanocrystalline Al-Zr samples are determined to be similar to the modulus of coarse-grained aluminum and independent of zirconium content.
Date: November 1, 1995
Creator: Rittner, M.N.; Weertman, J.R. & Eastman, J.A.
Partner: UNT Libraries Government Documents Department