National Library of Energy BETA

Sample records for al tes ti

  1. A=17Al (1993TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Al (1993TI07) (Not observed) See (1983ANZQ, 1988WA18, 1992AV03).

  2. A=16Al (1993TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    93TI07) (Not observed) See (1986AN07

  3. A=20Al, etc. (1998TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    98TI06) (Not observed) See (1972AJ02, 1983ANZQ, 1986AN07

  4. TI--CR--AL--O thin film resistors

    DOE Patents [OSTI]

    Jankowski, Alan F.; Schmid, Anthony P.

    2000-01-01

    Thin films of Ti--Cr--Al--O are used as a resistor material. The films are rf sputter deposited from ceramic targets using a reactive working gas mixture of Ar and O.sub.2. Resistivity values from 10.sup.4 to 10.sup.10 Ohm-cm have been measured for Ti--Cr--Al--O film <1 .mu.m thick. The film resistivity can be discretely selected through control of the target composition and the deposition parameters. The application of Ti--Cr--Al--O as a thin film resistor has been found to be thermodynamically stable, unlike other metal-oxide films. The Ti--Cr--Al--O film can be used as a vertical or lateral resistor, for example, as a layer beneath a field emission cathode in a flat panel display; or used to control surface emissivity, for example, as a coating on an insulating material such as vertical wall supports in flat panel displays.

  5. Anisotropic swelling and microcracking of neutron irradiated Ti3AlC2-Ti5Al2C3 materials

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ang, Caen K.; Silva, Chinthaka M.; Shih, Chunghao Phillip; Koyanagi, Takaaki; Katoh, Yutai; Zinkle, Steven J.

    2015-12-17

    Mn + 1AXn (MAX) phase materials based on Ti–Al–C have been irradiated at 400 °C (673 K) with fission neutrons to a fluence of 2 × 1025 n/m2 (E > 0.1 MeV), corresponding to ~ 2 displacements per atom (dpa). We report preliminary results of microcracking in the Al-containing MAX phase, which contained the phases Ti3AlC2 and Ti5Al2C3. Equibiaxial ring-on-ring tests of irradiated coupons showed that samples retained 10% of pre-irradiated strength. Volumetric swelling of up to 4% was observed. Phase analysis and microscopy suggest that anisotropic lattice parameter swelling caused microcracking. Lastly, variants of titanium aluminum carbide may bemore » unsuitable materials for irradiation at light water reactor-relevant temperatures.« less

  6. Effect of neutron irradiation on defect evolution in Ti3SiC2 and Ti2AlC

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tallman, Darin J.; He, Lingfeng; Garcia-Diaz, Brenda L.; Hoffman, Elizabeth N.; Kohse, Gordon; Sindelar, Robert L.; Barsoum, Michel W.

    2015-10-23

    Here, we report on the characterization of defects formed in polycrystalline Ti3SiC2 and Ti2AlC samples exposed to neutron irradiation – up to 0.1 displacements per atom (dpa) at 350 ± 40 °C or 695 ± 25 °C, and up to 0.4 dpa at 350 ± 40 °C. Black spots are observed in both Ti3SiC2 and Ti2AlC after irradiation to both 0.1 and 0.4 dpa at 350 °C. After irradiation to 0.1 dpa at 695 °C, small basal dislocation loops, with a Burgers vector of b = 1/2 [0001] are observed in both materials. At 9 ± 3 and 10 ±more » 5 nm, the loop diameters in the Ti3SiC2 and Ti2AlC samples, respectively, were comparable. At 1 × 1023 loops/m3, the dislocation loop density in Ti2AlC was ≈1.5 orders of magnitude greater than in Ti3SiC2, at 3 x 1021 loops/m3. After irradiation at 350 °C, extensive microcracking was observed in Ti2AlC, but not in Ti3SiC2. The room temperature electrical resistivities increased as a function of neutron dose for all samples tested, and appear to saturate in the case of Ti3SiC2. The MAX phases are unequivocally more neutron radiation tolerant than the impurity phases TiC and Al2O3. Based on these results, Ti3SiC2 appears to be a more promising MAX phase candidate for high temperature nuclear applications than Ti2AlC.« less

  7. Adhesion evaluation of TiN and (Ti, Al)N coatings on titanium 6Al-4V

    SciTech Connect (OSTI)

    James, R.D.; Gruss, K.A.; Horie, Y.; Davis, R.F.; Paisley, D.L.; Parthasarthi, S.; Tittmann, B.R.

    1996-12-31

    The metallic components of gas turbine engines are continually subjected to hostile atmospheres. Nitride coatings improve the performance of the metallic compressor blades in these engines. To assess the adhesion of nitride coatings on metals, titanium 6% aluminum 4% vanadium substrates were coated with titanium nitride (TiN) using both cathodic arc and electron beam evaporation. Titanium aluminum nitride ((Ti, Al)N) was also deposited using cathodic arc evaporation. The interfaces of the coated samples were loaded in tension using a high speed shock wave which caused spallation either at the interface, in the coating or in the metal. Scanning acoustic microscopy analysis of the spalled samples detected delaminations at the interface in the samples deposited by cathodic arc evaporation. DYNA2D modeling of plate impact spallation experiments revealed the tensile adhesion strength for TiN deposited by both techniques was {approx} 2.0 GPa. The tensile adhesion strength for (Ti, Al)N was less than 1.5 GPa.

  8. Growth and stress-induced transformation of zinc blende AlN layers in Al-AlN-TiN multilayers

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Li, Nan; Yadav, Satyesh K.; Wang, Jian; Liu, Xiang -Yang; Misra, Amit

    2015-12-18

    We report that AlN nanolayers in sputter deposited {111}Al/AlN/TiN multilayers exhibit the metastable zinc-blende-structure (z-AlN). Based on density function theory calculations, the growth of the z-AlN is ascribed to the kinetically and energetically favored nitridation of the deposited aluminium layer. In situ nanoindentation of the as-deposited {111}Al/AlN/TiN multilayers in a high-resolution transmission electron microscope revealed the z-AlN to wurzite AlN phase transformation through collective glide of Shockley partial dislocations on every two {111} planes of the z-AlN.

  9. Enhanced hardness in epitaxial TiAlScN alloy thin films and rocksalt TiN/(Al,Sc)N superlattices

    SciTech Connect (OSTI)

    Saha, Bivas; Lawrence, Samantha K.; Bahr, David F.; Schroeder, Jeremy L.; Birch, Jens; Sands, Timothy D.

    2014-10-13

    High hardness TiAlN alloys for wear-resistant coatings exhibit limited lifetimes at elevated temperatures due to a cubic-AlN to hexagonal-AlN phase transformation that leads to decreasing hardness. We enhance the hardness (up to 46 GPa) and maximum operating temperature (up to 1050 °C) of TiAlN-based coatings by alloying with scandium nitride to form both an epitaxial TiAlScN alloy film and epitaxial rocksalt TiN/(Al,Sc)N superlattices on MgO substrates. The superlattice hardness increases with decreasing period thickness, which is understood by the Orowan bowing mechanism of the confined layer slip model. These results make them worthy of additional research for industrial coating applications.

  10. Microstructure evolution during annealing of TiAl/NiCoCrAl multilayer composite prepared by EB-PVD

    SciTech Connect (OSTI)

    Zhang, Rubing; Zhang, Deming; Chen, Guiqing; Wang, Yuesheng

    2014-07-01

    TiAl/NiCoCrAl laminate composite sheet with a thickness of 0.4–0.6 mm as well as a dimension of 150 mm × 100 mm was fabricated successfully by using electron beam physical vapor deposition (EB-PVD) method. The annealing treatment was processed at 1123 and 1323 K for 3 h in a high vacuum atmosphere, respectively. The phase composition and microstructure of TiAl/NiCoCrAl microlaminated sheet have been analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Based on the sheet characterization and results of the microstructure evolution during annealing treatment process, the diffusion mechanism of interfacial reaction in TiAl/NiCoCrAl microlaminate was investigated and discussed.

  11. Catalytic Effect of Ti for Hydrogen Cycling in NaAlH4 | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Catalytic Effect of Ti for Hydrogen Cycling in NaAlH4 Catalytic Effect of Ti for Hydrogen Cycling in NaAlH4 A presentation about how hydrogen can be reversibly absorbed and desorbed from NaAlH4 under moderate conditions by the addition of catalysts. catalytic_effect_of_ti.pdf (877.97 KB) More Documents & Publications Final Report for the DOE Metal Hydride Center of Excellence Effects of Point Defects and Impurities on Kinetics in NaAlH4 Prediction of New Hydrogen Storage Compounds

  12. Structural, morphological and interfacial characterization of Al-Mg/TiC composites

    SciTech Connect (OSTI)

    Contreras, A. . E-mail: acontrer@imp.mx; Angeles-Chavez, C.; Flores, O.; Perez, R.

    2007-08-15

    Morphological and structural characterization of Al-Mg/TiC composites obtained by infiltration process and wetting by the sessile drop technique were studied. Focusing at the interface, wetting of TiC substrates by molten Al-Mg-alloys at 900 deg. C was investigated. Electron probe microanalysis (EPMA) indicated that aluminum carbide (Al{sub 4}C{sub 3}) is formed at the interface and traces of TiAl{sub 3} in the wetting assemblies were detected. Scanning Electron Microscopy (SEM) observations show that TiC particles do not appear to be uniformly attacked to produce a continuous layer of Al{sub 4}C{sub 3} at the interface. Molten Al-Mg-alloys were infiltrated into TiC preforms with flowing argon at a temperature of 900 deg. C. In the composites no reaction phase was observed by SEM. Quantification of the Al phase in the composite was carried out by X-ray diffraction (XRD) and Rietveld analysis. Chemical mapping analyzed by SEM shows that the Al-Mg alloy surrounds TiC particles. In the composites with 20 wt.% of Mg the Al-Mg-{beta} phase was detected through XRD.

  13. An Experimental and Theoretical Multi-Mbar Study of Ti-6Al-4V

    SciTech Connect (OSTI)

    Tegner, B E; Macleod, S G; CYNN, H; Proctor, J; Evans, W J; McMahon, M I; Ackland, G J

    2011-04-13

    We report results from an experimental and theoretical study of the room temperature (RT) compression of the ternary alloy Ti-6Al-4V. In this work, we have extended knowledge of the equation of state (EOS) from 40 GPa to 221 GPa, and observed a different sequence of phase transitions to that reported previously for pure Ti.

  14. An experimental study of the (Ti-6Al-4V)-xH phase diagram using...

    Office of Scientific and Technical Information (OSTI)

    An experimental study of the (Ti-6Al-4V)-xH phase diagram using in situ synchrotron XRD and TGADSC techniques This content will become publicly available on February 10, 2017 ...

  15. Process for producing Ti-Cr-Al-O thin film resistors

    DOE Patents [OSTI]

    Jankowski, Alan F.; Schmid, Anthony P.

    2001-01-01

    Thin films of Ti-Cr-Al-O are used as a resistor material. The films are rf sputter deposited from ceramic targets using a reactive working gas mixture of Ar and O.sub.2. Resistivity values from 10.sup.4 to 10.sup.10 Ohm-cm have been measured for Ti-Cr-Al-O film <1 .mu.m thick. The film resistivity can be discretely selected through control of the target composition and the deposition parameters. The application of Ti-Cr-Al-O as a thin film resistor has been found to be thermodynamically stable, unlike other metal-oxide films. The Ti-Cr-Al-O film can be used as a vertical or lateral resistor, for example, as a layer beneath a field emission cathode in a flat panel display; or used to control surface emissivity, for example, as a coating on an insulating material such as vertical wall supports in flat panel displays.

  16. Flat panel display using Ti-Cr-Al-O thin film

    DOE Patents [OSTI]

    Jankowski, Alan F.; Schmid, Anthony P.

    2002-01-01

    Thin films of Ti--Cr--Al--O are used as a resistor material. The films are rf sputter deposited from ceramic targets using a reactive working gas mixture of Ar and O.sub.2. Resistivity values from 10.sup.4 to 10.sup.10 Ohm-cm have been measured for Ti--Cr--Al--O film <1 .mu.m thick. The film resistivity can be discretely selected through control of the target composition and the deposition parameters. The application of Ti--Cr--Al--O as a thin film resistor has been found to be thermodynamically stable, unlike other metal-oxide films. The Ti--Cr--Al--O film can be used as a vertical or lateral resistor, for example, as a layer beneath a field emission cathode in a flat panel display; or used to control surface emissivity, for example, as a coating on an insulating material such as vertical wall supports in flat panel displays.

  17. Recyclability study on Inconel 718 and Ti-6Al-4V powders for...

    Office of Scientific and Technical Information (OSTI)

    Ti-6Al-4V, on the other hand, finds its reuse time governed by the oxygen pick up that occurs during and in between build cycles. The detailed results have been presented. Authors: ...

  18. Adhesion strength of sputtered TiAlN-coated WC insert tool

    SciTech Connect (OSTI)

    Budi, Esmar; Razali, M. Mohd.; Nizam, A. R. Md.

    2013-09-09

    The adhesion strength of TiAlN coating that deposited by using DC magnetron sputtering on WC insert tool are studied. TiAlN coating are deposited on Tungsten Carbide (WC) insert tool by varying negatively substrate bias from 79 to 221 volt and nitrogen flow rate from 30 to 72 sccm. The adhesion strength are obtained by using Rockwell indentation test method with a Brale diamond at applied load of 60,100 and 150 kgf. The lateral diameter of indentation is plotted on three different applied loads and the adhesion strength of TiAlN coating was obtained from the curved slopes at 100 and 150 kgf. The lower curve slop indicated better adhesion strength. The results shows that the adhesion strength of sputterred TiAlN coating tend to increase as the negatively substrate bias and nitrogen flow rate are increased.

  19. Supersaturated Al(Ti) solid solutions with partial L1{sub 2} ordering prepared by mechanical alloying

    SciTech Connect (OSTI)

    Fan, G.J.; Quan, M.X.; Hu, Z.Q.

    1995-08-01

    The authors report phase formation during mechanical alloying of Al rich Ti-Al powder blends. Their experimental results further support the idea that the synthesis of Al rich supersaturated solid solutions in the Al-Ti system occurs in the following two steps. First, the ordered L1{sub 2}-Al{sub 3}Ti intermetallic compound is formed at Al/Ti interfaces. Second, the ordered L1{sup 2}-Al{sub 3}Ti compound was partially disordered by mechanical deformation. Meanwhile, Ti or Al atoms dissolve into the partially disordered phase and a supersaturated solid solution is finally obtained. However, the disordering is not complete and the resulting alloys may exhibit partial L1{sub 2} ordering.

  20. Laser cladding of Ti-6Al-4V with various carbide powders

    SciTech Connect (OSTI)

    Folkes, J.A.; Shibata, K. )

    1994-06-01

    Laser cladding Ti-6Al-4V can be achieved with various weight percentages of different carbide powders. The microstructure and morphology of the clad layer is determined by the cladding powder composition, for a given set of laser parameters, such that 10 and 20 wt% Cr[sub 3]C[sub 2] results in a [beta] + TiC clad microstructure; 10 and 20 wt% WC results in an [alpha] + TiC clad microstructure (plus some original WC); and Mo[sub 2]C gives an [alpha] + [beta] + TiC or [beta] + TiC structure, depending on the weight percentage of Mo[sub 2]C. The morphology of the TiC in all cases is dendritic or feathery, depending on the carbide content. The microstructure observed in all cases agreed well with that theoretically predicted from the energetics of carbide formation and [beta]-stabilizing properties of each element.

  1. A new phase in rapidly solidified Ti[sub 3]Al-based alloys

    SciTech Connect (OSTI)

    Xu Rui; Xu Daming; Li Qingchun . Dept. of Materials Science and Engineering); Li Dong; Cui Yuyou; Hu Zhuangqi . State Key Lab. for RSA)

    1995-01-15

    Rapid solidification processing has been developed to improve the properties of alloys through refining microstructures, disordering and forming metastable phases. The as-melt spun Ti[sub 3]Al-based alloy with Nb additions above 5-at%, which consist of [alpha][sub 2] and [beta][sub 0] phases in a normal condition, exhibited as single [beta][sub 0] structure. Jackson et al have carried out a comparative study of I/M and RS Ti[sub 3]Al-1 Zr(at%) alloy. Their study revealed that considerable refinement of grains and anti-phase domains was achieved in the rapidly solidified material prepared by the pendant drop melt extraction process (PDME). It is suggested that rapid solidification processing can reduce the ordering of the Ti[sub 3]Al-based alloy. In the past years, it was found that the Ti[sub 3]Al-based alloy with alloying additions (mainly Nb) has been studied extensively, and some new phases such as T and O have been observed in the alloys, but less attention has been given to alloys with low Nb additions. The RS Ti[sub 3]Al-base alloys with Nb below 5-at% have been investigated systematically and a new metastable phase, ordering martensite [alpha][double prime][sub 0] (orthogonal), has been observed in these alloys.

  2. Reactivity enhancement of oxide skins in reversible Ti-doped NaAlH{sub 4}

    SciTech Connect (OSTI)

    Delmelle, Renaud; Borgschulte, Andreas; Gehrig, Jeffrey C.; Züttel, Andreas

    2014-12-15

    The reversibility of hydrogen sorption in complex hydrides has only been shown unambiguously for NaAlH{sub 4} doped with transition metal compounds. Despite a multitude of investigations of the effect of the added catalyst on the hydrogen sorption kinetics of NaAlH{sub 4}, the mechanism of catalysis remains elusive so far. Following the decomposition of TiCl{sub 3}-doped NaAlH{sub 4} by in-situ X-ray photoelectron spectroscopy (XPS), we link the chemical state of the dopant with those of the hydride and decomposition products. Titanium and aluminium change their oxidation states during cycling. The change of the formal oxidation state of Al from III to zero is partly due to the chemical reaction from NaAlH{sub 4} to Al. Furthermore, aluminium oxide is formed (Al{sub 2}O{sub 3}), which coexists with titanium oxide (Ti{sub 2}O{sub 3}). The interplay of metallic and oxidized Ti with the oxide skin might explain the effectiveness of Ti and similar dopants (Ce, Zr…)

  3. Improving the osteointegration of Ti6Al4V by zeolite MFI coating

    SciTech Connect (OSTI)

    Li, Yong; Jiao, Yilai; Li, Xiaokang; Guo, Zheng

    2015-05-01

    Osteointegration is crucial for success in orthopedic implantation. In recent decades, there have been numerous studies aiming to modify titanium alloys, which are the most widely used materials in orthopedics. Zeolites are solid aluminosilicates whose application in the biomedical field has recently been explored. To this end, MFI zeolites have been developed as titanium alloy coatings and tested in vitro. Nevertheless, the effect of the MFI coating of biomaterials in vivo has not yet been addressed. The aim of the present work is to evaluate the effects of MFI-coated Ti6Al4V implants in vitro and in vivo. After surface modification, the surface was investigated using field emission scanning electron microscopy (FE-SEM) and energy dispersive spectroscopy (EDS). No difference was observed regarding the proliferation of MC3T3-E1 cells on the Ti6Al4V (Ti) and MFI-coated Ti6Al4V (M−Ti) (p > 0.05). However, the attachment of MC3T3-E1 cells was found to be better in the M−Ti group. Additionally, ALP staining and activity assays and quantitative real-time RT-PCR indicated that MC3T3-E1 cells grown on the M−Ti displayed high levels of osteogenic differentiation markers. Moreover, Van-Gieson staining of histological sections demonstrated that the MFI coating on Ti6Al4V scaffolds significantly enhanced osteointegration and promoted bone regeneration after implantation in rabbit femoral condylar defects at 4 and 12 weeks. Therefore, this study provides a method for modifying Ti6Al4V to achieve improved osteointegration and osteogenesis. - Highlights: • Osteointegration is a crucial factor for orthopedic implants. • We coated MFI zeolite on Ti6Al4V substrates and investigated the effects in vitro and in vivo. • The MFI coating displayed good biocompatibility and promoted osteogenic differentiation in vitro. • The MFI coating promoted osteointegration and osteogenesis peri-implant in vivo.

  4. Industrial Application of Thin Films (TiAl)N Deposited on Thermo-Wells

    SciTech Connect (OSTI)

    Velez, G.; Jaramillo, S.; Arango, Y. C.; Devia, D.; Quintero, J.; Devia, A.

    2006-12-04

    The thermo-well is formed by two layers, one layer is a ceramic and the other layer is anviloy (comprised tungsten). They are used to coat the thermocouple in the control temperature system during the Aluminum-Silicon alloy melting process. After two weeks of continuous work at 750 deg. C of temperature (the alloy temperature), a high wear in this material is observed, affecting the ceramic. (TiAl)N thin films are deposited directly on the anviloy substrates by the PAPVD (Plasma Assisted Physics Vapor Deposition) in arc pulsed technique, using a TiAl target in a mono-vaporizer system, composed by a reactor and a power controlled system. Two opposite electrodes are placed into the reactor and discharge is produced by a controlled power system. The XRD (X-ray diffraction) patterns show the presence of the (TiAl)N thin film peaks. The morphological characteristics are studied by the scanning probe microscopy (SPM)

  5. Thermo-mechanical processing (TMP) of Ti-48Al-2Nb-2Cr based alloys

    SciTech Connect (OSTI)

    Fuchs, G.E.

    1995-02-01

    The effects of heat treatment and deformation processing on the microstructures and properties of {gamma}-TiAl based alloys produced by ingot metallurgy (I/M) and powder metallurgy (P/M) techniques were examined. The alloy selected for this work is the second generation {gamma}-TiAl based alloy -- Ti-48Al-2Nb-2Cr (at %). Homogenization of I/M samples was performed at a variety of temperatures, followed by hot working by isothermal forging. P/M samples were prepared from gas atomized powders, consolidated by both HIP and extrusion and some of the HIPed material was then hot worked by isothermal forging. The effects of processing, heat treatment and hot working on the microstructures and properties will be discussed.

  6. Initial oxidation of TiAl: An ab-initio investigation

    SciTech Connect (OSTI)

    Bakulin, Alexander V. Kulkova, Svetlana E.; Hu, Qing-Miao; Yang, Rui

    2014-11-14

    We present ab-initio investigation of oxygen adsorption up to two monolayer coverage on the stoichiometric TiAl(100) surface to illustrate the initial oxidation stage. The formation of band gap near the Fermi level demonstrates the transformation from metal to oxide surface with increasing oxygen coverage. The oxidation of Ti rather than Al is observed from our electronic structure calculations. The energy barriers of oxygen diffusion between different sites on surface as well as in subsurface and bulk region are derived. It is shown that the diffusion of oxygen is much easier on the surface than that into the subsurface region.

  7. Isothermal oxidation behavior and microstructure of plasma surface Ta coating on ?-TiAl

    SciTech Connect (OSTI)

    Song, Jian; Zhang, Ping-Ze Wei, Dong-Bo; Wei, Xiang-Fei; Wang, Ya

    2014-12-15

    The oxidation behavior of ?-TiAl with Ta surface coating fabricated by double glow plasma surface alloying technology was investigated by thermogravimetric method. Oxidation experiments were carried out at 750 C and 850 C in air for 100 h. The modification layer was comprised of deposition layer and diffusion layer, which metallurgically adhered to the substrate. Tantalum element decreased with the case depth. The oxidation morphology was studied by a scanning electron microscope and X-ray diffraction. The results highlighted that in the oxidizing process of the oxidation, the phase containing Ta-richer may restrain diffusing outward of the element Al in the matrix. Ti diffused outward, and formed the TiO{sub 2} scales, while the middle layer was rich in Al, and formed the continuous Al{sub 2}O{sub 3} scales after oxidation, which was effective to prevent further infiltration of oxygen atoms, and as a result the oxidation resistance increased immensely. - Highlights: A Ta modified coating was prepared on ?-TiAl using DGP surface alloying technology. The modification layer metallurgically adhered to the substrate. The bonding force is about 60 N, satisfying the demands of practical use. The oxidation resistance increased immensely at 750 C and 850 C.

  8. The study of crack resistance of TiAlN coatings under mechanical loading and thermal cycle testing

    SciTech Connect (OSTI)

    Akulinkin, Alexandr Shugurov, Artur Sergeev, Viktor; Panin, Alexey; Cheng, C.-H.

    2015-10-27

    The effect of preliminary ion bombardment of 321 stainless steel substrate on crack resistance of TiAlN coatings at uniaxial tension and thermal cycling is studied. The ion-beam treatment of the substrate is shown to substantially improve the adhesion strength of the coatings that prevents their delamination and spalling under uniaxial tension. The resistance to crack propagation and spalling by the thermal shock is higher in the TiAlN coating deposited onto the substrate subjected to Ti ion bombardment as compared to that in the TiAlN coating deposited onto the initial substrate.

  9. Degradation mechanisms of Ti/Al/Ni/Au-based Ohmic contacts on AlGaN/GaN HEMTs

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Hwang, Ya-Hsi; Ahn, Shihyun; Dong, Chen; Zhu, Weidi; Kim, Byung-Jae; Le, Lingcong; Ren, Fan; Lind, Aaron G.; Dahl, James; Jones, Kevin S.; et al

    2015-04-27

    We investigated the degradation mechanism of Ti/Al/Ni/Au-based Ohmic metallization on AlGaN/GaN high electron mobility transistors upon exposure to buffer oxide etchant (BOE). The major effect of BOE on the Ohmic metal was an increase of sheet resistance from 2.89 to 3.69 Ω/ₜafter 3 min BOE treatment. The alloyed Ohmic metallization consisted 3–5 μm Ni-Al alloy islands surrounded by Au-Al alloy-rings. The morphology of both the islands and ring areas became flatter after BOE etching. Lastly, we used energy dispersive x-ray analysis and Auger electron microscopy to analyze the compositions and metal distributions in the metal alloys prior to and aftermore » BOE exposure.« less

  10. In situ nanoindentation study of plastic Co-deformation in Al-TiN nanocomposites

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Li, N.; Wang, H.; Misra, A.; Wang, J.

    2014-10-16

    We performed in situ indentation in a transmission electron microscope on Al-TiN multilayers with individual layer thicknesses of 50 nm, 5 nm and 2.7 nm to explore the effect of length scales on the plastic co-deformability of a metal and a ceramic. At 50 nm, plasticity was confined to the Al layers with easy initiation of cracks in the TiN layers. At 5 nm and below, cracking in TiN was suppressed and post mortem measurements indicated a reduction in layer thickness in both layers. Our results demonstrate the profound size effect in enhancing plastic co-deformability in nanoscale metal-ceramic multilayers.

  11. Thermal protection of H13 steel by growth of (TiAl)N films by PAPVD pulsed arc technique

    SciTech Connect (OSTI)

    Jimenez, H.; Devia, D.M.; Benavides, V.; Devia, A. Arango, Y.C.; Arango, P.J.; Velez, J.M.

    2008-08-15

    (TiAl)N Films were grown on H13 steel by a plasma assisted repetitive pulsed arc discharge. To grow the coatings, a TiAl sintered cathode was used, 50% Ti-50% Al. The deposition system consists of a reaction chamber with two electrodes placed face to face. A pulsed power supply, which allows for control of parameters like time active arc, time between arcs, arc energy, and others, is used to generate the discharge. Thermal changes were carried out on H13 steel before and after growing the (TiAl)N films. X-ray diffraction (XRD) was employed to study the coatings, observing the H13 steel and (TiAl)N oxidation temperature. Morphological characteristics were analyzed by means of an Atomic Force Microscopy (AFM). Scanning electron microscopy (SEM) revealed the surface chemical composition of the films and morphological details of the samples.

  12. Processing, properties, and wear resistance of aluminides. [Fe[sub 3]Al; Al[sub 3]Ti

    SciTech Connect (OSTI)

    Wright, R.N.; Rabin, B.H.; Wright, J.K.

    1993-03-01

    Fully dense alloys based on Fe[sub 3]Al were produced by reaction synthesis from low cost elemental powders using hot pressing, hot isostatic pressing or Ceracon process. The reaction proceeds by outward spreading of a transient liquid phase from the initial aluminum particle site and precipitation of the compound phase from the liquid. Combustion synthesized material has a very fine grain size that is resistant to coarsening at high temperature because of a high density of fine oxides from the prior particle boundaries. The fine grain size results in approximately twice the yield strength in the reaction synthesized material compared to hot extruded pre-alloyed powder. Combustion synthesis has also been successfully applied to joining Fe[sub 3]Al and to forming coatings on carbon steel substrates. Combustion synthesis has been shown to be viable for fabricating trialuminides from elemental powder compacts. Al[sub 3]Ti, Al[sub 73]Ti[sub 24]Cr[sub 3] and Al[sub 67]Ti[sub 25]Cr[sub 8] were examined. Fully dense, homogeneous materials exhibiting an equiaxed grain structure were produced by conducting reaction and homogenization under pressure, or in a furnace at ambient pressure and subsequently densifying the porous preform by hot consolidation. The tetragonal DO[sub 22] structure was the primary reaction product for all compositions. Most of the Cr remained undissolved after reaction and a homogenization heat treatment at 1200C or above was used to put the Cr into solution and form the desired L1[sub 2] phase.

  13. Influence of the Al distribution on the structure, elastic properties, and phase stability of supersaturated Ti{sub 1-x}Al{sub x}N

    SciTech Connect (OSTI)

    Mayrhofer, P. H.; Music, D.; Schneider, J. M.

    2006-11-01

    Ti{sub 1-x}Al{sub x}N films and/or their alloys are employed in many industrial applications due to their excellent mechanical and thermal properties. Synthesized by plasma-assisted vapor deposition, Ti{sub 1-x}Al{sub x}N is reported to crystallize in the cubic NaCl (c) structure for AlN mole fractions below 0.4-0.91, whereas at larger Al contents the hexagonal ZnS-wurtzite (w) structure is observed. Here we use ab initio calculations to analyze the effect of composition and Al distribution on the metal sublattice on phase stability, structure, and elastic properties of c-Ti{sub 1-x}Al{sub x}N and w-Ti{sub 1-x}Al{sub x}N. We show that the phase stability of supersaturated c-Ti{sub 1-x}Al{sub x}N not only depends on the chemical composition but also on the Al distribution of the metal sublattice. An increase of the metastable solubility limit of AlN in c-Ti{sub 1-x}Al{sub x}N from 0.64 to 0.74 is obtained by decreasing the number of Ti-Al bonds. This can be understood by considering the Al distribution induced changes of the electronic structure, bond energy, and configurational entropy. This may in part explain the large variation of the metastable solubility limit reported in the literature.

  14. Effect of neutron irradiation on defect evolution in Ti3SiC2 and Ti2AlC

    SciTech Connect (OSTI)

    Tallman, Darin J.; He, Lingfeng; Garcia-Diaz, Brenda L.; Hoffman, Elizabeth N.; Kohse, Gordon; Sindelar, Robert L.; Barsoum, Michel W.

    2015-10-23

    Here, we report on the characterization of defects formed in polycrystalline Ti3SiC2 and Ti2AlC samples exposed to neutron irradiation – up to 0.1 displacements per atom (dpa) at 350 ± 40 °C or 695 ± 25 °C, and up to 0.4 dpa at 350 ± 40 °C. Black spots are observed in both Ti3SiC2 and Ti2AlC after irradiation to both 0.1 and 0.4 dpa at 350 °C. After irradiation to 0.1 dpa at 695 °C, small basal dislocation loops, with a Burgers vector of b = 1/2 [0001] are observed in both materials. At 9 ± 3 and 10 ± 5 nm, the loop diameters in the Ti3SiC2 and Ti2AlC samples, respectively, were comparable. At 1 × 1023 loops/m3, the dislocation loop density in Ti2AlC was ≈1.5 orders of magnitude greater than in Ti3SiC2, at 3 x 1021 loops/m3. After irradiation at 350 °C, extensive microcracking was observed in Ti2AlC, but not in Ti3SiC2. The room temperature electrical resistivities increased as a function of neutron dose for all samples tested, and appear to saturate in the case of Ti3SiC2. The MAX phases are unequivocally more neutron radiation tolerant than the impurity phases TiC and Al2O3. Based on these results, Ti3SiC2 appears to be a more promising MAX phase candidate for high temperature nuclear applications than Ti2AlC.

  15. Deformation and fracture behavior of composite structured Ti-Nb-Al-Co(-Ni) alloys

    SciTech Connect (OSTI)

    Okulov, I. V. Marr, T.; Schultz, L.; Eckert, J.; Khn, U.; Freudenberger, J.; Oertel, C.-G.; Skrotzki, W.

    2014-02-17

    Tensile ductility of the Ti-based composites, which consist of a ?-Ti phase surrounded by ultrafine structured intermetallics, is tunable through the control of intermetallics. The two Ti-based alloys studied exhibit similar compressive yield strength (about 1000?MPa) and strain (about 35%40%) but show a distinct difference in their tensile plasticity. The alloy Ti{sub 71.8}Nb{sub 14.1}Ni{sub 7.4}Al{sub 6.7} fractures at the yield stress while the alloy Ti{sub 71.8}Nb{sub 14.1}Co{sub 7.4}Al{sub 6.7} exhibits about 4.5% of tensile plastic deformation. To clarify the effect of microstructure on the deformation behavior of these alloys, tensile tests were carried out in the scanning electron microscope. It is shown that the distribution as well as the type of intermetallics affects the tensile ductility of the alloys.

  16. Environmental effect on room-temperature ductility of isothermally forged TiAl-base alloys

    SciTech Connect (OSTI)

    Nakamura, Morihiko; Hashimoto, Kenki (National Research Inst. for Metals, Tokyo (Japan)); Itoh, Naoyuki (Nippon Steel Corp., Chiba (Japan)); Tsujimoto, Tokuzo (Ibaraki Univ. (Japan). Faculty of Engineering); Suzuki, Toshiyuki (Kougakuin Univ., Tokyo (Japan))

    1994-02-01

    Isothermally forged TiAl-base alloy (Al-rich, Mn-containing, and Cr-containing TiAl) were heat-treated in various conditions, and equiaxed grain structures consisting of [gamma] and [alpha][sub 2] or [beta] phases were obtained. The heat-treated alloys were tensile tested in vacuum and air at room temperature, and the environmental effect on tensile elongation was studied. The ductility of the alloys consisting of equiaxed [gamma] grains and a large amount of [alpha][sub 2] grains was not largely affecting by laboratory air, and a decrease in the amount of [alpha][sub 2] grains resulted in a large reduction of ductility in air. The [beta] phase in the Cr-containing alloy improved the ductility in vacuum, but it resulted in a large reduction of ductility in air.

  17. An Experimental and Theoretical Study of Ti-6Al-4V to Multi-mbar Pressures

    SciTech Connect (OSTI)

    MacLeod, S G; Tegner, B E; Cynn, H; Evans, W J; Proctor, J; McMahon, M I; Ackland, G J

    2012-03-14

    We report results from an experimental and theoretical study of the ternary alloy Ti-6Al-4V to 221 GPa. We observe a phase transition to the hexagonal {omega}-phase at approximately 30 GPa, and then a further transition to the cubic {beta}-phase starting at 94-99 GPa. We do not observe the orthorhombic {gamma} and {delta} phases reported previously in pure Ti. Computational studies show that this sequence is possible only if there is significant local atomic ordering during the compression process, yet insufficient atomic diffusion to reach the phase separated thermodynamic equilibrium state.

  18. Characterization of Mg/Al butt joints welded by gas tungsten arc filling with Zn29.5Al0.5Ti filler metal

    SciTech Connect (OSTI)

    Liu, Fei; Wang, Hongyang; Liu, Liming, E-mail: liulm@dlut.edu.cn

    2014-04-01

    The multivariate alloying design of a welding joint is used in the Mg to Al welding process. A Zn29.5Al0.5Ti alloy is added as filler metal in gas tungsten arc welding of Mg and Al alloy joint based on the analysis of Al and Mg alloy characteristics. The tensile strength, microstructure, and phase constitution of the weld seam are analyzed. The formation of brittle and hard MgAl intermetallic compounds is avoided because of the effects of Zn, Al, and Ti. The average tensile strength of the joint is 148 MPa. Al{sub 3}Ti is first precipitated and functions as the nucleus of heterogeneous nucleation during solidification. Moreover, the precipitated AlMgZn{sub 2} hypoeutectic phase exhibited a feather-like structure, which enhances the property of the MgAl dissimilar joint. - Highlights: Mg alloy AZ31B and Al alloy 6061 are butt welded by fusion welding. The effect of Ti in filler metal is investigated. The formation of MgAl intermetallic compounds is avoided.

  19. Ab initio modeling of zincblende AlN layer in Al-AlN-TiN multilayers

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Yadav, S. K.; Wang, J.; Liu, X. -Y.

    2016-06-13

    An unusual growth mechanism of metastable zincblende AlN thin film by diffusion of nitrogen atoms into Al lattice is established. Using first-principles density functional theory, we studied the possibility of thermodynamic stability of AlN as a zincblende phase due to epitaxial strains and interface effect, which fails to explain the formation of zincblende AlN. We then compared the formation energetics of rocksalt and zincblende AlN in fcc Al through direct diffusion of nitrogen atoms to Al octahedral and tetrahedral interstitials. Furthermore, the formation of a zincblende AlN thin film is determined to be a kinetically driven process, not a thermodynamicallymore » driven process.« less

  20. Spin-dependent transport across Co/LaAlO{sub 3}/SrTiO{sub 3} heterojunctions

    SciTech Connect (OSTI)

    Swartz, Adrian G.; Harashima, Satoshi; Xie, Yanwu; Kim, Bongju; Hwang, Harold Y.; Lu, Di; Bell, Christopher; Hikita, Yasuyuki

    2014-07-21

    The conducting interface formed between LaAlO{sub 3} and SrTiO{sub 3} exhibits high electron mobility, tunable carrier densities, and is theoretically predicted to have long spin lifetimes. Thus, the LaAlO{sub 3}/SrTiO{sub 3} heterostructure is a promising system for the transportation of spin information. We have investigated spin-dependent transport across Co/LaAlO{sub 3}/SrTiO{sub 3} heterostructures using an all electrical three terminal geometry and observed Lorentzian magnetoresistance typically associated with Hanle spin dephasing. However, such a picture fails to explain all the experimentally observed behavior. Further, experiments with spin-unpolarized Au/LaAlO{sub 3}/SrTiO{sub 3} heterojunctions support an alternative scenario involving current modulation by spin-dependent transport through defect states in the LaAlO{sub 3} barrier.

  1. Observation of Precipitation Evolution in Fe-Ni-Mn-Ti-Al Maraging Steel using Atom Probe Tomography

    SciTech Connect (OSTI)

    Pereloma, E. V.; Stohr, R A; Miller, Michael K; Ringer, S. P.

    2009-01-01

    We describe the full decomposition sequence in an Fe-Ni-Mn-Ti-Al maraging steel during isothermal annealing at 550 C. Following significant pre-precipitation clustering reactions within the supersaturated martensitic solid solution, (Ni,Fe){sub 3}Ti and (Ni,Fe){sub 3}(Al,Mn) precipitates eventually form after isothermal aging for {approx}60 seconds. The morphology of the (Ni,Fe){sub 3}Ti particles changes gradually during aging from predominantly plate-like to rod-like, and, importantly, Mn and Al were observed to segregate to these precipitate/matrix interfaces. The (Ni,Fe){sub 3}(Al,Mn) precipitates occurred at two main locations: uniformly within the matrix and at the periphery of the (Ni,Fe){sub 3}Ti particles. We relate this latter mode of precipitation to the Mn-Al segregation.

  2. Catalytic Effect of Ti for Hydrogen Cycling in NaAlH4

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Catalytic Effect of Ti for Hydrogen Cycling in NaAlH 4 Mei-Yin Chou School of Physics Georgia Institute of Technology (DE-FG02-05ER46229) Acknowledgment: Yan Wang, Roland Stumpf Why is NaAlH 4 interesting? A viable candidate for hydrogen-storage material: High theoretical weight-percent hydrogen content of 5.55% and low cost But (before 1997) Dehydrogenation occurs at high temperature; rehydrogenation is difficult. Bogdanovic and Schwickardi, 1997 Hydrogen can be reversibly absorbed and desorbed

  3. Thermal stability of Ni/Ti/Al ohmic contacts to p-type 4H-SiC

    SciTech Connect (OSTI)

    Yu, Hailong; Shen, Huajun Tang, Yidan; Bai, Yun; Liu, Xinyu; Zhang, Xufang; Wu, Yudong; Liu, Kean

    2015-01-14

    Low resistivity Ni/Ti/Al ohmic contacts on p-type 4H-SiC epilayer were developed, and their thermal stabilities were also experimentally investigated through high temperature storage at 600 °C for 100 h. The contact resistance of the Al/Ti/Ni/SiC contacts degraded in different degrees, and the contact morphology deteriorated with the increases of the average surface roughness and interface voids. X-ray spectra showed that Ni{sub 2}Si and Ti{sub 3}SiC{sub 2}, which were formed during ohmic contact annealing and contributed to low contact resistivity, were stable under high temperature storage. The existence of the TiAl{sub 3} and NiAl{sub 3} intermetallic phases was helpful to prevent Al agglomeration on the interface and make the contacts thermally stable. Auger electron spectroscopy indicated that the incorporation of oxygen at the surface and interface led to the oxidation of Al or Ti resulting in increased contact resistance. Also, the formation of these oxides roughened the surface and interface. The temperature-dependence of the specific contact resistance indicated that a thermionic field emission mechanism dominates the current transport for contacts before and after the thermal treatment. It suggests that the Ni/Ti/Al composite ohmic contacts are promising for SiC devices to be used in high temperature applications.

  4. Composition, morphology and mechanical properties of sputtered TiAlN coating

    SciTech Connect (OSTI)

    Budi, Esmar; Razali, M. Mohd.; Nizam, A. R. Md.

    2014-03-24

    TiAlN coating was deposited on the tungsten carbide cutting tool by using DC magnetron sputtering system to study the influence of substrate bias and nitrogen flow rate on the composition, morphology and mechanical properties. The negatively substrate bias and nitrogen flow rate was varied from about ?79 to ?221 V and 30 sccm to 72 sccm, respectively. The coating composition and roughness were characterized by using SEM/EDX and Atomic Force Microscopy (AFM), respectively. The dynamic ultra micro hardness tester was used to measure the mechanical properties. The coating hardness increases to about 10-12 GPa with an increase of the negatively substrate bias up to ? 200 V and it tend to decrease with an increase in nitrogen flow rate up to 70 sccm. The increase of hardness follows the increase of Ti and N content and rms coating roughness.

  5. Brazing ZrO{sub 2} ceramic to Ti6Al4V alloy using NiCrSiB amorphous filler foil: Interfacial microstructure and joint properties

    SciTech Connect (OSTI)

    Cao, J., E-mail: cao_jian@hit.edu.cn [Shandong Provincial Key Laboratory of Special Welding Technology, Harbin Institute of Technology at Weihai, Weihai 264209 (China); State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); Song, X.G., E-mail: song_xiaoguohit@yahoo.com.cn [Shandong Provincial Key Laboratory of Special Welding Technology, Harbin Institute of Technology at Weihai, Weihai 264209 (China); State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); Li, C., E-mail: li_chun1989@yahoo.cn [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); Zhao, L.Y., E-mail: Zhao_ly@163.com [State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China); Feng, J.C., E-mail: feng_jicai@163.com [Shandong Provincial Key Laboratory of Special Welding Technology, Harbin Institute of Technology at Weihai, Weihai 264209 (China); State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001 (China)

    2013-07-15

    Reliable brazing of ZrO{sub 2} ceramic and Ti6Al4V alloy was achieved using NiCrSiB amorphous filler foil. The interfacial microstructure of ZrO{sub 2}/Ti6Al4V joints was characterized by scanning electron microscope, energy dispersive spectrometer and micro-focused X-ray diffractometer. The effects of brazing temperature on the interfacial microstructure and joining properties of brazed joints were investigated in detail. Active Ti of Ti6Al4V alloy dissolved into molten filler metal and reacted with ZrO{sub 2} ceramic to form a continuous TiO reaction layer, which played an important role in brazing. Various reaction phases including Ti{sub 2}Ni, Ti{sub 5}Si{sub 3} and ?-Ti were formed in brazed joints. With an increasing of brazing temperature, the TiO layer thickened gradually while the Ti{sub 2}Ni amount reduced. Shear test indicated that brazed joints tend to fracture at the interface between ZrO{sub 2} ceramic and brazing seam or Ti{sub 2}Ni intermetallic layer. The maximum average shear strength reached 284.6 MPa when brazed at 1025 C for 10 min. - Graphical Abstract: Interfacial microstructure of ZrO{sub 2}/TC4 joint brazed using NiCrSiB amorphous filler foil was: ZrO{sub 2}/TiO/Ti{sub 2}Ni + ?-Ti + Ti{sub 5}Si{sub 3}/?-Ti/Widmansttten structure/TC4. - Highlights: Brazing of ZrO{sub 2} ceramic and Ti-6Al-4V alloy was achieved. Interfacial microstructure was TiO/Ti{sub 2}Ni + ? + Ti{sub 5}Si{sub 3}/?/Widmansttten structure. The formation of TiO produced the darkening effect of ZrO{sub 2} ceramic. The highest joining strength of 284.6MPa was obtained.

  6. TesSol Inc | Open Energy Information

    Open Energy Info (EERE)

    search Name: TesSol Inc Place: Texas Zip: 77808 Product: Solutions provider to fuel cell developers, catalyst companies, and research centres around the world. References:...

  7. High-Temperature Galling Characteristics of Ti-6Al-4V with and without Surface Treatments

    SciTech Connect (OSTI)

    Blau, Peter Julian; ERDMAN III, DONALD L; Ohriner, Evan Keith; Jolly, Brian C

    2011-01-01

    Galling is a severe form of surface damage in metals and alloys that typically arises under relatively high normal force, low-sliding speed, and in the absence of effective lubrication. It can lead to macroscopic surface roughening and seizure. The occurrence of galling can be especially problematic in high-temperature applications like diesel engine exhaust gas recirculation system components and adjustable turbocharger vanes, because suitable lubricants may not be available, moisture desorption promotes increased adhesion, and the yield strength of metals decreases with temperature. Oxidation can counteract these effects to some extent by forming lubricative oxide films. Two methods to improve the galling resistance of titanium alloy Ti-6Al-4V were investigated: (a) applying an oxygen diffusion treatment, and (b) creating a metal-matrix composite with TiB2 using a high-intensity infrared heating source. A new, oscillating three-pin-on-flat, high-temperature test method was developed and used to characterize galling behavior relative to a cobalt-based alloy (Stellite 6B ). The magnitude of the oscillating torque, the surface roughness, and observations of surface damage were used as measures of galling resistance. Owing to the formation of lubricative oxide films, the galling resistance of the Ti-alloy at 485o C, even non-treated, was considerably better than it was at room temperature. The IR-formed composite displayed reduced surface damage and lower torque than the substrate titanium alloy.

  8. Theoretical Assessment on the Phase Transformation Kinetic Pathways of Multi-component Ti Alloys: Application to Ti-6Al-4V

    SciTech Connect (OSTI)

    Ji, Yanzhou; Heo, Tae Wook; Zhang, Fan; Chen, Long-Qing

    2015-12-21

    Here we present our theoretical assessment of the kinetic pathways during phase transformations of multi-component Ti alloys. Employing the graphical thermodynamic approach and an integrated free energy function based on the realistic thermodynamic database and assuming that a displacive structural transformation occurs much faster than long-range diffusional processes, we analyze the phase stabilities of Ti-6Al-4V (Ti-6wt.%Al-4wt.%V). Our systematic analyses predict a variety of possible kinetic pathways for β to (α + β) transformations leading to different types of microstructures under various heat treatment conditions. In addition, the possibility of unconventional kinetic pathways is discussed. Lastly, we also briefly discuss the application of our approach to general multicomponent/multiphase alloy systems.

  9. A transmission electron microscopy study of the deformation behavior underneath nanoindents in nano-scale Al-TiN multilayered composites

    SciTech Connect (OSTI)

    Bhattacharyya, Dhriti; Mara, Nathan A; Dickerson, Patricia O; Misra, Amit; Hoagland, R G

    2009-01-01

    Nano-scale multilayered Al-TiN composites were deposited with DC magnetron sputtering technique in two different layer thickness ratios - Al:TiN = 1:1 and Al:TiN = 9:1. The Al layer thickness varied from 2 nm to 450 nm. The hardness of the samples was tested by nanoindentation using a Berkovich tip. Cross-sectional Transmission Electron Microscopy (TEM) was carried out on samples extracted with Focused Ion Beam (FIB) from below the nanoindents. This paper presents the results of the hardness tests in the Al-TiN multilayers with the two different thickness ratios and the observations from the cross-sectional TEM studies of the regions underneath the indents. These studies showed remarkable strength in the multilayers, as well as some very interesting deformation behavior in the TiN layers at extremely small length scales, where the hard TiN layers undergo co-deformation with the Al layers.

  10. Effect of cryogenic treatment on the plastic property of Ti-6Al-4V titanium alloy

    SciTech Connect (OSTI)

    Gu, K. X.; Wang, J. J.; Yuan, Z.; Zhang, H.; Li, Z. Q.; Zhao, B.

    2014-01-27

    The effect of cryogenic treatment on the plastic property of Ti-6Al-4V plate was studied in the present work. After cryogenic treatment, the low temperature temper at 180 ▭ was conducted in one of the groups and the results were compared with that of the untreated and cryotreated ones. The SLX series program controlled cryogenic equipment was used for the cryogenic treatment. The tensile tests were conducted by universal tensile testing machine and parameters of elongation and area reduction were used to evaluate plastic property. The scanning electron microscope was used to study the morphology of microstructure and fracture surface. The results show that after cryogenic treatment alone the elongation increased 10.6% and the area reduction increased 13.5% while the strength reduced to a small extent. Cryogenic treatment followed with low temperature temper increased the elongation and area reduction just by the extent of 4.7% and 9.5%. It means that the additional low temperature temper after cryogenic is not beneficial to the tensile properties of Ti-6Al-4V alloy. The examination of microstructure by scanning electron microscopy revealed that cryogenic treatment reduced the content of β phase particles which is the main reason for the improvement in plasticity.

  11. Thermodynamic Instability at the Stoichiometric LaAlO3/SrTiO3(001) Interface

    SciTech Connect (OSTI)

    Qiao, Liang; Droubay, Timothy C.; Shutthanandan, V.; Zhu, Zihua; Sushko, P. V.; Chambers, Scott A.

    2010-08-11

    Fully stoichiometric epitaxial LaAlO3 grown on the TiO2-terminated SrTiO3(001) by off-axis pulsed laser deposition is shown to exhibit strong La-Sr cation intermixing. This result is predicted by classical and quantum mechanical calculations of the relative stabilities of abrupt and intermixed states. The extensive cation intermixing has a marked impact on the electronic properties of the interface.

  12. Tribological Characteristics of Single-phase AlMgB14 and Nanocomposite AlMgB14-TiB2 Superhard Coatings

    SciTech Connect (OSTI)

    Qu, Jun; Blau, Peter Julian; Zhu, Dong; Cook, Bruce A; Elmoursi, Alaa A

    2008-01-01

    This study investigated the friction and wear characteristics of AlMgB14 and AlMgB14-TiB2 superhard coatings, produced by pulse laser deposition (PLD) and physical vapor deposition (PVD), respectively. Tests were conducted under unidirectional and reciprocating sliding against AISI 52100 bearing steel in both dry and oil-lubricated conditions. The AlMgB14 coating exhibited an encouraging but short-lived low friction stage (u = 0.2) in dry sliding. The AlMgB14-TiB2 coating reduced the wear rates by one order of magnitude for itself and three orders of magnitude for the counterface compared with the uncoated M2 tool steel in dry sliding. This nanocomposite coating also demonstrated significant extension (>2.5X) of the low friction (non-scuffing) stage in a lubricant starvation sliding.

  13. Effect of Ti-Al cathode composition on plasma generation and plasma transport in direct current vacuum arc

    SciTech Connect (OSTI)

    Zhirkov, I. Petruhins, A.; Dahlqvist, M.; Ingason, A. S.; Rosen, J.; Eriksson, A. O.

    2014-03-28

    DC arc plasma from Ti, Al, and Ti{sub 1-x}Al{sub x} (x?=?0.16, 0.25, 0.50, and 0.70) compound cathodes was characterized with respect to plasma chemistry and charge-state-resolved ion energy. Scanning electron microscopy, X-ray diffraction, and Energy-dispersive X-ray spectroscopy of the deposited films and the cathode surfaces were used for exploring the correlation between cathode-, plasma-, and film composition. Experimental work was performed at a base pressure of 10{sup ?6}?Torr, to exclude plasma-gas interaction. The plasma ion composition showed a reduction of Al of approximately 5 at. % compared to the cathode composition, while deposited films were in accordance with the cathode stoichiometry. This may be explained by presence of neutrals in the plasma/vapour phase. The average ion charge states (Ti?=?2.2, Al?=?1.65) were consistent with reference data for elemental cathodes, and approximately independent on the cathode composition. On the contrary, the width of the ion energy distributions (IEDs) were drastically reduced when comparing the elemental Ti and Al cathodes with Ti{sub 0.5}Al{sub 0.5}, going from??150 and ?175?eV to ?100 and ?75?eV for Ti and Al ions, respectively. This may be explained by a reduction in electron temperature, commonly associated with the high energy tail of the IED. The average Ti and Al ion energies ranged between ?50 and ?61?eV, and ?30 and ?50?eV, respectively, for different cathode compositions. The attained energy trends were explained by the velocity rule for compound cathodes, which states that the most likely velocities of ions of different mass are equal. Hence, compared to elemental cathodes, the faster Al ions will be decelerated, and the slower Ti ions will be accelerated when originating from compound cathodes. The intensity of the macroparticle generation and thickness of the deposited films were also found to be dependent on the cathode composition. The presented results may be of importance for choice of

  14. Validation of TES Temperature and Water Vapor Retrievals with...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    The primary objective of the TES (Tropospheric Emission Spectrometer) instrument on the Aura spacecraft is the retrieval of trace gases, especially water vapor and ozone. The TES...

  15. Electric field effects in graphene/LaAlO{sub 3}/SrTiO{sub 3} heterostructures and nanostructures

    SciTech Connect (OSTI)

    Huang, Mengchen; Jnawali, Giriraj; Hsu, Jen-Feng; Dhingra, Shonali; Bi, Feng; Chen, Lu; DUrso, Brian; Irvin, Patrick; Levy, Jeremy; Lee, Hyungwoo; Ryu, Sangwoo; Eom, Chang-Beom; Ghahari, Fereshte; Ravichandran, Jayakanth; Kim, Philip

    2015-06-01

    We report the development and characterization of graphene/LaAlO{sub 3}/SrTiO{sub 3} heterostructures. Complex-oxide heterostructures are created by pulsed laser deposition and are integrated with graphene using both mechanical exfoliation and transfer from chemical-vapor deposition on ultraflat copper substrates. Nanoscale control of the metal-insulator transition at the LaAlO{sub 3}/SrTiO{sub 3} interface, achieved using conductive atomic force microscope lithography, is demonstrated to be possible through the graphene layer. LaAlO{sub 3}/SrTiO{sub 3}-based electric field effects using a graphene top gate are also demonstrated. The ability to create functional field-effect devices provides the potential of graphene-complex-oxide heterostructures for scientific and technological advancement.

  16. Symmetry-dependent interfacial reconstruction to compensate polar discontinuity at perovskite oxide interfaces (LaAlO{sub 3}/SrTiO{sub 3} and LaAlO{sub 3}/CaTiO{sub 3})

    SciTech Connect (OSTI)

    Lee, Joohwi; Moon, Seon Young; Kim, Jin-Sang; Choi, Jung-Hae E-mail: almacore@kist.re.kr; Choi, Jong Kwon; Park, Jaehong; Hwang, Cheol Seong; Baek, Seung-Hyub; Chang, Hye Jung E-mail: almacore@kist.re.kr

    2015-02-16

    We report the crystal symmetry-dependency of the interfacial reconstruction to relieve the polar discontinuity at the complex oxide heterointerfaces. We chose LaAlO{sub 3}/SrTiO{sub 3} and LaAlO{sub 3}/CaTiO{sub 3} interfaces as model systems, where the neutral TiO{sub 2} and the positive LaO{sup +} layers form the polar discontinuity at the interface with TiO{sub 2}-terminated (001) cubic SrTiO{sub 3} and orthorhombic CaTiO{sub 3}. Using scanning transmission electron microscopy, we observed that the interlayer distance abnormally increased at the interface. We performed the first-principles calculations to understand the detailed atomic displacement at the interfaces having no oxygen vacancy and intermixing. Our results show that cations were reconstructed in different ways depending on the crystal symmetry through the octahedral tilts and atomic displacements to compensate the polar discontinuity at the interfaces. Our results imply that the interfacial reconstructions have to be considered along with the ionic compensation (intermixing) and electronic compensation (two dimensional electron gas) to fully understand the interfacial phenomena.

  17. Microstructure characterization of laser welded Ti-6Al-4V fusion zones

    SciTech Connect (OSTI)

    Xu, Pei-quan; Li, Leijun, E-mail: leijun.li@ualberta.ca; Zhang, Chunbo

    2014-01-15

    The as-welded microstructure of laser-welded Ti-6Al-4V is characterized as a function of CO2 key-hole mode laser welding speed. Martensitic ?? is the predominant phase, with some ? and retained ?. Phase transformation is affected by the cooling rate through laser welding speed. A higher welding speed of 1.6 to 2.0 m/min produced more martensite ?? and less retained ? in the welds. 1.4 m/min welding speed produced small amounts of ?, besides the martensite ??. A trace of ? titanium hydride phase seems to have formed in the weld fusion zone. Moir fringes are a common feature in the TEM microstructure, due to abundance of multi-phase interfaces. Tensile twins and clusters of dislocations indicate that plastic deformation has happened in the as-welded microstructure, indicating the local stress levels to be approaching the yield stress on-cooling during laser welding.

  18. In-situ single-grain peak profile measurements on Ti-7Al during tensile deformation.

    SciTech Connect (OSTI)

    Lienert, U.; Brandes, M. C.; Bernier, J. V.; Weiss, J.; Shastri, S. D.; Mills, M. J.; Miller, M. P.; US Naval Research Lab.; LLNL; Mechanical Solutions, Inc.; Ohio State Univ.; Cornell Univ.

    2009-10-25

    High-energy three-dimensional X-ray diffraction with medium and high reciprocal space resolution was applied to study in situ tensile deformation of Ti-7Al specimens. Samples with planar and random dislocation microstructures were prepared and characterized by electron microscopy. Stress tensors of individual grains were obtained at several loads up to 2% deformation. The stress tensors were found to rotate, and resolved shear stresses were calculated. High-resolution reciprocal space maps of selected grains were recorded. Azimuthal and radial distributions were visualized and discussed in terms of idealized dislocation structures. Heterogeneous grain rotations were observed for the planar microstructure and found to be consistent with activation of the highest stressed basal slip system. Intra-granular strain gradients were detected in excess of the intrinsic radial dislocation peak broadening. The potential of combining the applied techniques with modeling to obtain multiple length-scale information during deformation of bulk specimens is discussed.

  19. HRTEM Study of Oxide Nanoparticles in 16Cr-4Al-2W-0.3Ti-0.3Y2O3...

    Office of Scientific and Technical Information (OSTI)

    ...6Cr-4Al-2W-0.3Ti-0.3Y2O3 ODS Steel Citation Details In-Document Search Title: HRTEM Study of Oxide Nanoparticles in 16Cr-4Al-2W-0.3Ti-0.3Y2O3 ODS Steel You are accessing a ...

  20. HRTEM Study of Oxide Nanoparticles in 16Cr-4Al-2W-0.3Ti-0.3Y2O3...

    Office of Scientific and Technical Information (OSTI)

    HRTEM Study of Oxide Nanoparticles in 16Cr-4Al-2W-0.3Ti-0.3Y2O3 ODS Steel Citation Details In-Document Search Title: HRTEM Study of Oxide Nanoparticles in 16Cr-4Al-2W-0.3Ti-0.3Y2O3 ...

  1. Microstructure characterization and mechanical behaviors of a hot forged high Nb containing PM-TiAl alloy

    SciTech Connect (OSTI)

    Li, Jianbo; Liu, Yong; Liu, Bin; Wang, Yan; Liang, Xiaopeng; He, Yuehui

    2014-09-15

    In this work, the effects of deformation on the microstructure and mechanical behaviors of TiAl alloy were investigated. Deformed microstructure observation was characterized by scanning electron microscopy, electron back scattered diffraction technique, transmission electron microscopy and DEFORM-3D software. Results indicated that the core area of the TiAl pancake was characterized by completely dynamically recrystallized microstructures, however some residual lamellar colonies can be observed near the edge area, which are primarily caused by a temperature drop and inhomogenous plastic flow. The main softening mechanism is dynamic recrystallization of γ grains. The as-forged alloy exhibited excellent mechanical properties at both room temperature and high temperature. Tensile test results showed that the ultimate tensile strength of the alloy increased from 832 MPa at room temperature to 853 MPa at 700 °C, while the elongation increased from 2.7% to 17.8%. Even at the temperature of 850 °C, the ultimate tensile strength maintained 404 MPa, and the elongation increased to 75%. The as-forged alloy also exhibited remarkable low-temperature superplasticity at 850 °C, with an elongation of 120%. - Highlights: • The core area of the TiAl pancake was characterized by DRX microstructure. • The elongation at RT is higher than that of other high Nb-containing TiAl alloys. • The forged alloy exhibited low-temperature superplasticity at 850 °C.

  2. Electronic and atomic structures of Ti{sub 1-x}Al{sub x}N thin films related to their damage behavior

    SciTech Connect (OSTI)

    Tuilier, M.-H.; Pac, M.-J.; Girleanu, M.; Covarel, G.; Arnold, G.; Louis, P.; Rousselot, C.; Flank, A.-M.

    2008-04-15

    Ti and Al K-edge x-ray absorption spectroscopy is used to investigate the electronic structure of Ti{sub 1-x}Al{sub x}N thin films deposited by reactive magnetron sputtering. The experimental near edge spectra of TiN and AlN are interpreted in the light of unoccupied density of state band structure calculations. The comparison of the structural parameters derived from x-ray absorption fine structure and x-ray diffraction reveals segregation between Al-rich and Ti-rich domains within the Ti{sub 1-x}Al{sub x}N films. Whereas x-ray diffraction probes only the crystallized domains, the structural information derived from extended x-ray absorption fine structure analysis turns on both crystalline and grain boundaries. The results are discussed by considering the damage behavior of the films depending on the composition.

  3. Current TES Capabilities in TRNSYS (Presentation)

    SciTech Connect (OSTI)

    Price, H.; Blair, N.

    2003-02-01

    This presentation includes: a brief overview of TRNSYS, a review of current SolarPaces models, potential of other models appropriate for CSP TES, and a review of a project proposal.

  4. The defect-induced changes of the electronic and magnetic properties in the inverse Heusler alloy Ti{sub 2}CoAl

    SciTech Connect (OSTI)

    Chen, Ying; Wu, Bo; Yuan, Hongkuan; Feng, Yu; Chen, Hong

    2015-01-15

    The first-principles calculations are performed to investigate the effect of swap, antisite and vacancy defects of three classes on the electronic and magnetic properties in the inverse Heusler alloy Ti{sub 2}CoAl of half-metallicity. Our calculations reveal that Ti(A/B)–Co and Co–Al swaps, Ti(A/B) and Al vacancy defects as well as Co{sub Ti(A)/Al} and Al{sub Ti(A)/Ti(B)} antisite defects are likely to form in a concentration as high as 12.5%. Among them, Co{sub Ti(A)} antisite is detected to be the most probable defect. It is shown that the spin polarizations of Ti{sub 2}CoAl are considerably reduced by the Ti(A/B)–Co swap and Ti(B)/Al vacancy defects, while a quite high spin polarization around 95% is observed in Co–Al swap as well as Ti(A) vacancy. Remarkably, all the likely antisite defects almost retain the half-metallic character in a concentration of 12.5% even if they have the possibility to form. However, induced by antisites, the Fermi levels shift to the edge of band gap with small peaks arising just above the Fermi level, which may destroy the half-metallicity by spin-flip excitation. - Graphical abstract: The spin polarization and formation energy of various possible defects in inverse Heusler alloy Ti{sub 2}CoAl. The triangle, star and square represent the swap, antisite and vacancy defects, respectively. - Highlights: • The swap, antisite, and vacancy defects are studied in half-metallic Ti{sub 2}CoAl. • The Co{sub Ti(A)} antisite is the most probable among the studied defects. • The antisite defects almost retain the half-metallicity. • Most of swap and vacancy defects have degraded the half-metallicity. • High spin polarizations are detected in Co–Al swap and Ti(A) vacancy defects.

  5. Mechanically driven phase transformation from crystal to glass in Ti-Al binary system

    SciTech Connect (OSTI)

    Fan, G.J.; Quan, M.X.; Hu, Z.Q. . National Key Lab for RSA)

    1995-01-15

    Metastable phases such as metallic glass have been widely studied during the past few years. A number of techniques have been employed to synthesize these alloys, among which, mechanical alloying (MA) was considered to be a promising tool for large production and economical operation. However, the mechanism of formation of the metastable phases during mechanical alloying/ball milling have not been well determined. Previous studies of amorphization by mechanical alloying of pure elements or ball milling of intermetallics have proposed the following mechanics: rapid quenching of local melts produced by mechanical impacts, high density of defects generated by mechanical deformation which raises the free energy of compound to above that of the amorphous phase, effective local temperature rise at the collision site which gives rise to a solid-state reaction similar to thin film diffusion couples. Most of the studies have suggested that solid-state-type reactions are most likely to be responsible for vitrification during mechanical alloying, and the kinetics was controlled by the point and lattice defects generated by mechanical deformation. In the Zr-Al alloy system, however, another mechanisms was proposed by Fecht et al. based on a chemically induced catastrophic transition. The amorphization was interpreted with the elastic instability of crystal caused by the atomic mismatch of two components in supersaturated solid solution; when solute concentration reaches a critical value, the supersaturated solid solution becomes metastable and a polymorphous melting'' transition to a glass may occur. This hypothesis has been further examined by Ma and Atzmon with calorimeter measurements. In this paper, it will be shown experimentally that this mechanism may be valid in the Ti-Al binary system.

  6. Cation mixing, band offsets and electric fields at LaAlO3/SrTiO3(001) heterojunctions with variable La:Al atom ratio

    SciTech Connect (OSTI)

    Qiao, Liang; Droubay, Timothy C.; Kaspar, Tiffany C.; Sushko, P. V.; Chambers, Scott A.

    2011-08-01

    Interfacial intermixing and electronic structure were investigated at thin (35 unit cells.), epitaxial La1 ? xAl1 + xO3/SrTiO3(001) heterojunctions for x = 0 and 0.05. Angle-resolved X-ray photoelectron spectroscopy reveals rather extensive cation intermixing for all films, independent of composition. The valence band offset for the nominally stoichiometric (x = 0) film is 0.16 0.10 eV, with the valence band maximum of SrTiO3 being deeper in binding energy than that of LaAlO3. Similar values are obtained for x = 0.05. There is no measurable band bending in either the LaAlO3 or the SrTiO3 near the interface. These results are at odds with first principles theoretical predictions based on perfect stoichiometry and an abrupt interface model. However, inclusion of intermixing in the compositional description of the interface results in successful prediction of the valence band offset and absence of band bending.

  7. Photoconductivity and Non-Exponential Relaxation at Insulating LaAlO3/SrTiO3 Interfaces

    SciTech Connect (OSTI)

    Kim, Minu; Bell, C.; Hikita, Y.; Kozuka, Y.; Kim, B.G.; Hwang, H.Y.

    2012-08-17

    LaAlO{sub 3} is grown on SrO terminated (100) SrTiO{sub 3}, and (110) SrTiO{sub 3}, producing insulating heterointerfaces without light. Photocurrent spectroscopy at low temperatures reveals a broad distribution of interface states between 2 eV and 2.7 eV at both interfaces, with a higher density in the (110) case concomitant with relatively shallow traps. The photocurrent relaxation can be well fitted by a stretched exponential form, confirming energetically distributed electron traps. Photo-carrier lifetimes are larger than a few hundred seconds for optical excitation approaching the SrTiO{sub 3} band-gap energy, providing the opportunity to study transient light-induced properties at low temperatures.

  8. Effect of the top electrode materials on the resistive switching characteristics of TiO{sub 2} thin film

    SciTech Connect (OSTI)

    Oh, Sang Chul; Jung, Ho Yong; Lee, Heon

    2011-06-15

    Various metals, such as Pt, stainless steel (SUS), Al, Ni, and Ti, were used as a top electrode (TE) to evaluate the dependency of the resistive switching characteristics on the TE of the metal/TiO{sub 2}/Pt structure. The variation of the chemical composition of TiO{sub 2} in the metal/TiO{sub 2}/Pt structure before and after switching was examined to identify the factors affecting the resistive switching characteristics of the samples with various TE materials. In the case of TE/TiO{sub 2}/Pt structures showing unstable resistive switching behavior, e.g., those with the Al, Ni, and Ti TEs, secondary ion mass spectrometry revealed an increase in the oxygen concentration at the interface area between the TE metal and TiO{sub 2}. This suggests that the oxidation reaction at the interface between the TE metal and TiO{sub 2} might cause the TE/TiO{sub 2}/Pt structure to exhibit unstable resistive switching characteristics. According to these results, the oxidation reaction at the interface between the metal TE and TiO{sub 2} thin film is a primary factor affecting the resistive switching characteristics of TiO{sub 2}-based Resistive Random Access Memory devices.

  9. Texture Evolution During Laser Direct Metal Deposition of Ti-6Al-4V

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sridharan, Niyanth; Chaudhary, Anil; Nandwana, Peeyush; Babu, Sudarsanam Suresh

    2016-01-20

    Titanium alloys are used in a wide variety of high performance applications and hence the processing of the titanium and the resulting microstructures after additive manufacturing has received significant attention. During additive manufacturing the processing route involves the transition from a liquid to solid state. The addition of successive layers results in a complex microstructure due to solid-state transformations. The current study focuses on understanding the phase transformations and relate it to the transformation texture in Ti-6Al-4V to identify conditions leading to a strong alpha transformation texture. The as deposited builds were characterized using optical microscopy and electron backscattered diffraction.more » The results showed columnar prior β grains with a martensitic structure after the deposition of a single layer. On subsequent depositions the martensitic microstructure decomposes to a colony and basketweave microstructure with a stronger transformation texture. The alpha texture with a colony and basketweave microstructure shows a stronger transformation texture as a result of variant selection. Thus by controlling the cooling rate of the build from the β transus it is possible to control the alpha transformation texture.« less

  10. High-temperature phase transformation in Cr added TiAl base alloy

    SciTech Connect (OSTI)

    Abe, E.; Niinobe, K.; Nobuki, M.; Nakamura, M.; Tsujimoto, T.

    1999-07-01

    The authors have investigated a microstructure evolution of a Ti-48Al-3.5Cr (in at.%) alloy at high-temperatures ({gt} 1,473K). In the alloy annealed at 1673K for 1.8ks, followed by air-cooling, a characteristic microstructure with a feathery fashion was uniformly formed. From a cooling-rate-controlling study, it was found that formation of the feathery structure is accomplished during continuous cooling from 1673K to 1573K, within the {alpha} + {gamma} two-phase region. Transmission electron microscopy revealed that the feathery structure is composed of lamellar colonies (5--10{micro}m) which are crystallographically tilted slightly (a few degree) with their neighbors. A surprising fact is that lamellae in each colony are mostly the {gamma} phase with few {alpha}{sub 2} phase less than 5% in volume. This suggests that the feathery structure is a metastable product and has not resulted from the {alpha} {r{underscore}arrow} {alpha} + {gamma} transformation above 1,573 K. Instead, the feathery structure formation should be attributed to the non-equilibrium {alpha} {r{underscore}arrow} {gamma} transformation which occurs at high-temperatures with a small degree of supercooling. The authors discuss this interesting phase transformation in terms of the {alpha} {r{underscore}arrow} {gamma} massive transformation, based on the continuous-cooling-transformation (CCT) diagram constructed for the present alloy.

  11. The distribution alloying elements in alnico 8 and 9 magnets: Site preference of ternary Ti, Fe, Co, and Ni additions in DO3 Fe3Al, Co3Al, and Ni3Al based intermetallic phases

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Samolyuk, G. D.; Újfalussy, B.; Stocks, G. M.

    2014-11-07

    Recently, interest in alnico magnetic alloys has been rekindled due to their potential to substitute for rare-earth based permanent magnets provided modest improvements in their coercivity can be achieved without loss of saturation magnetization. Recent experimental studies have indicated that atomic and magnetic structure of the two phases (one AlNi-based, the other FeCo-based) that comprise these spinodally decomposed alloy is not as simple as previously thought. A key issue that arises is the distribution of Fe, Co and Ti within the AlNi-based matrix phase. In our paper we report the results of first-principles calculations of the site preference of ternarymore » alloying additions in DO3 Fe3Al, Co3Al and Ni3Al alloys, as models for the aluminide phase. For compound compositions that are Al rich, which corresponds to experimental situation, Ti and Fe are found to occupy the sites, while Co and Ni prefer the sites of the DO3 lattice. Finally, an important finding is that the magnetic moments of transition metals in Fe3Al and Co3Al are ordered ferromagnetically, whereas the Ni3Al were found to be nonmagnetic unless the Fe or Co are added as a ternary element.« less

  12. Effect of a ductility layer on the tensile strength of TiAl-based multilayer composite sheets prepared by EB-PVD

    SciTech Connect (OSTI)

    Zhang, Rubing; Zhang, Yaoyao; Liu, Qiang; Chen, Guiqing; Zhang, Deming

    2014-09-15

    TiAl/Nb and TiAl/NiCoCrAl laminate composite sheets with a thickness of 0.4–0.6 mm and dimensions of 150 mm × 100 mm were successfully fabricated by electron beam physical vapor deposition. The microstructures of the sheets were examined, and their mechanical properties were compared with those of TiAl monolithic sheet produced by electron beam physical vapor deposition. Tensile testing was performed at room temperature and 750 °C, and the fracture surfaces were examined by scanning electron microscopy. Among the three microlaminate sheets, the TiAl/NiCoCrAl micro-laminate sheet had the best comprehensive properties at room temperature, and the TiAl/Nb micro-laminate sheet showed the ideal high-temperature strength and plasticity at 750 °C. The result was discussed in terms of metal strengthening mechanism. - Highlights: • TiAl-based multilayer foils was fabricated successfully by using EB-PVD method; • The tensile properties and micro-fracture morphologies of the sheet were investigated; • The deformation behavior of the multilayer foils was discussed.

  13. Equivalence of optical and electrical noise equivalent power of hybrid NbTiN-Al microwave kinetic inductance detectors

    SciTech Connect (OSTI)

    Janssen, R. M. J.; Endo, A.; Visser, P. J. de; Klapwijk, T. M.; Baselmans, J. J. A.

    2014-11-10

    We have measured and compared the response of hybrid NbTiN-Al Microwave Kinetic Inductance Detectors (MKIDs) to changes in bath temperature and illumination by sub-mm radiation. We show that these two stimulants have an equivalent effect on the resonance feature of hybrid MKIDs. We determine an electrical noise equivalent power (NEP) from the measured temperature responsivity, quasiparticle recombination time, superconducting transition temperature, and noise spectrum, all of which can be measured in a dark environment. For the two hybrid NbTiN-Al MKIDs studied in detail, the electrical NEP is within a factor of two of the optical NEP, which is measured directly using a blackbody source.

  14. Recyclability study on Inconel 718 and Ti-6Al-4V powders for use in electron beam melting

    SciTech Connect (OSTI)

    Nandwana, Peeyush; Peter, William H.; Lowe, Larry E.; Dehoff, Ryan R.; Medina, Francisco; Babu, Sudarsanam Suresh; Kirka, Michael M.

    2015-10-20

    In this study, powder bed based additive manufacturing technologies offer a big advantage in terms of reusability of the powders over multiple cycles that result in cost savings. However, currently there are no standards to determine the factors that govern the powder reuse times. This work presents the results from a recyclability study conducted on Inconel 718 and Ti-6Al-4V powders. It has been found that the Inconel 718 powders are chemically stable over a large number of cycles and their reuse time is limited by physical characteristics of powders such as flowability. Ti-6Al-4V, on the other hand, finds its reuse time governed by the oxygen pick up that occurs during and in between build cycles. The detailed results have been presented.

  15. Recyclability study on Inconel 718 and Ti-6Al-4V powders for use in electron beam melting

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Nandwana, Peeyush; Peter, William H.; Lowe, Larry E.; Dehoff, Ryan R.; Medina, Francisco; Babu, Sudarsanam Suresh; Kirka, Michael M.

    2015-10-20

    In this study, powder bed based additive manufacturing technologies offer a big advantage in terms of reusability of the powders over multiple cycles that result in cost savings. However, currently there are no standards to determine the factors that govern the powder reuse times. This work presents the results from a recyclability study conducted on Inconel 718 and Ti-6Al-4V powders. It has been found that the Inconel 718 powders are chemically stable over a large number of cycles and their reuse time is limited by physical characteristics of powders such as flowability. Ti-6Al-4V, on the other hand, finds its reusemore » time governed by the oxygen pick up that occurs during and in between build cycles. The detailed results have been presented.« less

  16. Stoichiometry dependence of potential screening at La ( 1 - δ ) Al ( 1 + δ ) O 3 / SrTiO 3 interfaces

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Weiland, Conan; Sterbinsky, George E.; Rumaiz, Abdul K.; Hellberg, C. Stephen; Woicik, Joseph C.; Zhu, Shaobo; Schlom, Darrell G.

    2015-04-03

    Hard x-ray photoelectron spectroscopy (HAXPES) and variable kinetic energy x-ray photoelectron spectroscopy (VKE-XPS) analyses have been performed on ten-unit-cell-thick La(1-δ)Al(1+δ)O₃ films, with La:Al ratios of 1.1, 1.0, and 0.9, deposited on SrTiO₃. Only Al-rich films are known to have a conductive interface. VKE-XPS, coupled with maximum entropy analysis, shows significant differences in the compositional depth profile among the Al-rich, La-rich, and stoichiometric films: significant La enrichment at the interface is observed in the La-rich and stoichiometric films, while the Al-rich film shows little to no intermixing. Additionally, the La-rich and stoichiometric films show a high concentration of Al at themore » surface, which is not observed in the Al-rich film. HAXPES valence band (VB) analysis shows a broadening of the VB for the Al-rich sample relative to the stoichiometric and La-rich samples. This broadening is consistent with an electric field across the Al-rich film. These results are consistent with a defect-driven electronic reconstruction.« less

  17. On the preparation of TiAl alloy by direct reduction of the oxide mixtures in calcium chloride melt

    SciTech Connect (OSTI)

    Prabhat K. Tripathy; Derek J. Fray

    2011-11-01

    In recent years, TiAl-based intermetallic alloys are being increasingly considered for application in areas such as (i) automobile/transport sector (passenger cars, trucks and ships) (ii) aerospace industry (jet engines and High Speed Civil Transport propulsion system) and (iii) industrial gas turbines. These materials offer excellent (i) high temperature properties (at higher than 6000C) (ii) mechanical strength and (iii) resistance to corrosion and as a result have raised renewed interest. The combination of these properties make them possible replacement materials for traditional nickel-based super-alloys, which are nearly as twice as dense (than TiAl based alloys). Since the microstructures of these intermetallic alloys affect, to a significant extent, their ultimate performance, further improvements (by way of alteration/modification of these microstructures), have been the subject matter of intense research investigations. It has now been established that the presence of alloy additives, such as niobium, tantalum, manganese, boron, chromium, silicon, nickel and yttrium etc, in specific quantities, impart marked improvement to the properties, viz. fatigue strength, fracture toughness, oxidation resistance and room temperature ductility, of these alloys. From a number of possible alloy compositions, {gamma}-TiAl and Ti-Al-Nb-Cr have, of late, emerged as two promising engineering alloys/materials. . The conventional fabrication process of these alloys include steps such as melting, forging and heat treatment/annealing of the alloy compositions. However, an electrochemical process offers an attractive proposition to prepare these alloys, directly from the mixture of the respective oxides, in just one step. The experimental approach, in this new process, was, therefore, to try to electrochemically reduce the (mixed) oxide pellet to an alloy phase. The removal of oxygen, from the (mixed) oxide pellet, was effected by polarizing the oxide pellet against a graphite

  18. An experimental study of the (Ti-6Al-4V)-xH phase diagram using in situ synchrotron XRD and TGA/DSC techniques.

    SciTech Connect (OSTI)

    Sun, Pei; Fang, Z. Zak; Koopman, Mark; Paramore, James D.; Chandran, K. S. Ravi; Ren, Yang; Lu, Jun

    2015-02-01

    Hydrogen has been investigated for decades as a temporary alloying element to refine the microstructure of Ti-6Al-4V, and is now being used in a novel powder metallurgy method known as "hydrogen sintering and phase transformation". Pseudo-binary phase diagrams of (Ti-6Al-4V)-xH have been studied and developed, but are not well established due to methodological limitations. In this paper, in situ studies of phase transformations during hydrogenation and dehydrogenation of (Ti-6Al-4V)-xH alloys were conducted using high-energy synchrotron X-ray diffraction (XRD), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The eutectoid phase transformation of ? ? ? + ? was observed in the (Ti-6Al-4V)-xH alloy via in situ synchrotron XRD at 211 C with a hydrogen concentration of 37.5 at.% (measured using TGA-DSC). The relationships of hydrogen composition to partial pressure and temperature were investigated in the temperature range 450-900C. Based on these results, a partial pseudo-binary phase diagram of (Ti-6Al-4V)-xH is proposed for hydrogen compositions up to 60 at.% in the temperature range 100-900C. Using the data collected in real time under controlled parameters of temperature, composition and hydrogen partial pressure, this work characterizes relevant phase transformations and microstructural evolution for practical titanium-hydrogen technologies of Ti-6Al-4V.

  19. Capacitance-voltage characteristics of (Al/Ti)/Al{sub 2}O{sub 3}/n-GaN MIS structures

    SciTech Connect (OSTI)

    Ivanov, P. A. Potapov, A. S.; Nikolaev, A. E.; Lundin, V. V.; Sakharov, A. V.; Tsatsulnikov, A. F.; Afanas’ev, A. V.; Romanov, A. A.; Osachev, E. V.

    2015-08-15

    The capacitance-voltage characteristics of (Al/Ti)/Al{sub 2}O{sub 3}/n-GaN metal—insulator-semiconductor (MIS) structures are measured and analyzed. n-Type GaN films are grown on sapphire (0001) substrates by the metal-organic chemical vapor deposition method. An aluminum-oxide layer with a thickness of 60 nm is deposited onto the surface of GaN by the method of atomic-layer deposition from the gas phase. Metallic contacts are deposited by the electron-beam evaporation of titanium and aluminum in vacuum. According to the measurement results, the breakdown-field strength of the oxide, its dielectric constant, and the integrated electron density of states at the oxide-semiconductor interface are 5 × 10{sup 6} V/cm, 7.5, and 3 × 10{sup 12} cm{sup −2}, respectively.

  20. Anisotropic swelling and microcracking of neutron irradiated Ti3AlC2-Ti5Al2C3 materials

    SciTech Connect (OSTI)

    Ang, Caen K.; Silva, Chinthaka M.; Shih, Chunghao Phillip; Koyanagi, Takaaki; Katoh, Yutai; Zinkle, Steven J.

    2015-12-17

    Mn + 1AXn (MAX) phase materials based on Ti–Al–C have been irradiated at 400 °C (673 K) with fission neutrons to a fluence of 2 × 1025 n/m2 (E > 0.1 MeV), corresponding to ~ 2 displacements per atom (dpa). We report preliminary results of microcracking in the Al-containing MAX phase, which contained the phases Ti3AlC2 and Ti5Al2C3. Equibiaxial ring-on-ring tests of irradiated coupons showed that samples retained 10% of pre-irradiated strength. Volumetric swelling of up to 4% was observed. Phase analysis and microscopy suggest that anisotropic lattice parameter swelling caused microcracking. Lastly, variants of titanium aluminum carbide may be unsuitable materials for irradiation at light water reactor-relevant temperatures.

  1. Temperature-dependent elastic properties of Ti{sub 1−x}Al{sub x}N alloys

    SciTech Connect (OSTI)

    Shulumba, Nina; Hellman, Olle; Rogström, Lina; Raza, Zamaan; Tasnádi, Ferenc; Odén, Magnus; Abrikosov, Igor A.

    2015-12-07

    Ti{sub 1−x}Al{sub x}N is a technologically important alloy that undergoes a process of high temperature age-hardening that is strongly influenced by its elastic properties. We have performed first principles calculations of the elastic constants and anisotropy using the symmetry imposed force constant temperature dependent effective potential method, which include lattice vibrations and therefore the effects of temperature, including thermal expansion and intrinsic anharmonicity. These are compared with in situ high temperature x-ray diffraction measurements of the lattice parameter. We show that anharmonic effects are crucial to the recovery of finite temperature elasticity. The effects of thermal expansion and intrinsic anharmonicity on the elastic constants are of the same order, and cannot be considered separately. Furthermore, the effect of thermal expansion on elastic constants is such that the volume change induced by zero point motion has a significant effect. For TiAlN, the elastic constants soften non-uniformly with temperature: C{sub 11} decreases substantially when the temperature increases for all compositions, resulting in an increased anisotropy. These findings suggest that an increased Al content and annealing at higher temperatures will result in a harder alloy.

  2. Investigation of the phase equilibrium of alloys of the ternary system Ti-Al-Nb

    SciTech Connect (OSTI)

    Nartova, T.T.; Sopochkin, G.G.

    1987-09-09

    This investigation of the constitution diagram of the ternary system titanium-aluminum-niobium is limited to the specific system Ti-Ti3A1-Nb in order to establish the regions of the alpha and beta solid solutions of titanium, the solid solutions based on aluminide Ti3A1, and the phases conjugated with them. The constitution diagram of the systems Ti-A1 and Ti-Nb obtained from the data were used as the basis for constructing the constitution diagram of the ternary system. The methods of microstructural, thermal and X ray phase analysis were used in the study. The X ray pictures were taken in copper emission from powders that had been preliminarily annealed in a vacuum at 600 for 30 min. Iodic titanium, aluminum brand AV-000 and fillet niobium were used as the source materials. The alloys were remelted five times in an electric-arc furnace with a nonconsumable tungsten electrode in an argon atmosphere, and then by crucibleless melting in the suspended state. The constancy of the chemical composition of the alloys was monitored by their weight after smelting in an electric arc furnace.

  3. Epitaxial growth, structure, and intermixing at the LaAlO{sub 3}/SrTiO{sub 3} interface as the film stoichiometry is varied

    SciTech Connect (OSTI)

    Qiao, L.; Droubay, T. C.; Kaspar, T. C.; Chambers, S. A.; Varga, T.; Bowden, M. E.; Shutthanandan, V.; Zhu, Z.

    2011-02-15

    LaAlO{sub 3} epitaxial films with La:Al cation ratios ranging from 0.9 to 1.2 were grown on TiO{sub 2}-terminated SrTiO{sub 3} (001) substrates by off-axis pulsed laser deposition. Although all films are epitaxial, rocking curve measurements show that the crystallographic quality degrades with increasing La:Al ratio. Films with La:Al ratios of 0.9, 1.0, and 1.1 were coherently strained to the substrate. However, the out-of-plane lattice parameter increases over this range, revealing a decrease in film tetragonality. Although all film surfaces exhibit hydroxylation, the extent of hydroxylation is greater for the La-rich films. Rutherford backscattering spectrometry reveals that La from the film diffuses deeply into the SrTiO{sub 3} substrate and secondary-ion-mass spectroscopy shows unambiguous Sr outdiffusion into the films.

  4. Solid-particle erosion of an Al{sub 2}O{sub 3}-SiC-TiC composite

    SciTech Connect (OSTI)

    Jiang, M.; Goretta, K.C.; Singh, D.; Routbort, J.L.; Schuldies, J.J.

    1996-11-01

    An electrodischarge-machinable Al{sub 2}O{sub 3}-SiC-TiC composite developed by Industrial Ceramic Technology, Inc., has a high fracture toughness, 9.6{+-}0.6 MPm{sup 1/2}, as measured by indentation, and a Vickers hardness of 20.3{+-}0.6 GPa. The composite`s resistance to solid-particle erosion was measured for 143-{mu}m dia SiC particles impacting at 20-90{degree} angles and 50-100 m/s velocities. Erosion rate exhibited a maximum for normal incidence, and the erosion resistance was better than that of commercial Al{sub 2}O{sub 3}. SEM indicated that material wastage was by a combination of brittle fracture and microplasticity.

  5. Octahedral rotations in strained LaAlO{sub 3}/SrTiO{sub 3} (001) heterostructures

    SciTech Connect (OSTI)

    Fister, T. T.; Hruszkewycz, S. O.; Proffit, D. L.; Eastman, J. A.; Fuoss, P. H.; Baldo, P. M.; Fong, D. D.; Zhou, H.; Luo, Z.; Seo, S. S. A.; Lee, H. N.

    2014-02-01

    Many complex oxides display an array of structural instabilities often tied to altered electronic behavior. For oxide heterostructures, several different interfacial effects can dramatically change the nature of these instabilities. Here, we investigate LaAlO{sub 3}/SrTiO{sub 3} (001) heterostructures using synchrotron x-ray scattering. We find that when cooling from high temperature, LaAlO{sub 3} transforms from the Pm3{sup }m to the Imma phase due to strain. Furthermore, the first 4 unit cells of the film adjacent to the substrate exhibit a gradient in rotation angle that can couple with polar displacements in films thinner than that necessary for 2D electron gas formation.

  6. Tunable bilayer two-dimensional electron gas in LaAlO{sub 3}/SrTiO{sub 3} superlattices

    SciTech Connect (OSTI)

    Ma, H. J. Harsan E-mail: phyarian@nus.edu.sg; Annadi, A.; Zeng, S. W.; Ariando E-mail: phyarian@nus.edu.sg; Huang, Z.; L, W. M.; Wong, L. M.; Wang, S. J.; Venkatesan, T.

    2014-07-07

    We report magnetotransport properties of double heterointerfaces in LaAlO{sub 3}/SrTiO{sub 3}/LaAlO{sub 3}/SrTiO{sub 3}(001) (LAO/STO/LAO/STO). A strong nonlinearity in the Hall resistivity is found when the temperature is below 80?K. This effect is attributed to multichannel conduction of interfacial charges generated in double heterostructures of LAO/STO where two-dimensional electron gas (2DEG) is produced. The multichannel conduction is confirmed by back gating modulation of Hall effect. Our result suggests the possibility to achieve coupled bilayer 2DEG layers in LAO/STO superlattices.

  7. Epitaxial growth, structure and intermixing at the LaAlO3/SrTiO3 interface as the film stoichiometry is varied

    SciTech Connect (OSTI)

    Qiao, Liang; Droubay, Timothy C.; Varga, Tamas; Bowden, Mark E.; Shutthanandan, V.; Zhu, Zihua; Kaspar, Tiffany C.; Chambers, Scott A.

    2011-02-11

    LaAlO3 epitaxial films with La:Al cation ratios ranging from 0.9 to 1.2 were grown on TiO2-terminated SrTiO3 (001) substrates by off-axis pulsed laser deposition. Although all films are epitaxial, rocking curve and Kiessig fringe oscillation measurements show that the crystallographic quality degrades with increasing La:Al ratio. Films with La:Al ratios of 0.9, 1.0, and 1.1 were coherently strained to the substrate. However, the out-of-plane lattice parameter increases over this range, revealing a decrease in film tetragonality. Although all film surfaces exhibit hydroxylation, the extent of hydroxylation is greater for the La-rich films. Rutherford backscattering spectrometry reveals that La from the film diffuses deeply into the SrTiO3 substrate and secondary ion mass spectroscopy shows unambiguous Sr outdiffusion into the films. Intermixing, which is generally not investigated in studies of the LaAlO3/SrTiO3 interface, may have important implications for the mechanism of electrical conductivity.

  8. Built-in and Induced Polarization Across LaAlO3/SrTiO3 Heterojunctions

    SciTech Connect (OSTI)

    Guneeta, Singh-Bhalla

    2011-08-15

    Ionic crystals terminated at oppositely charged polar surfaces are inherently unstable and expected to undergo surface reconstructions to maintain electrostatic stability. Essentially, an electric field that arises between oppositely charged atomic planes gives rise to a built-in potential that diverges with thickness. Here we present evidence of such a built-in potential across polar LaAlO{sub 3} thin films grown on SrTiO{sub 3} substrates, a system well known for the electron gas that forms at the interface. By performing tunneling measurements between the electron gas and metallic electrodes on LaAlO{sub 3} we measure a built-in electric field across LaAlO{sub 3} of 80.1 meV/{angstrom}. Additionally, capacitance measurements reveal the presence of an induced dipole moment across the heterostructure. We forsee use of the ionic built-in potential as an additional tuning parameter in both existing and novel device architectures, especially as atomic control of oxide interfaces gains widespread momentum.

  9. Galvanomagnetic properties of Fe{sub 2}YZ (Y = Ti, V, Cr, Mn, Fe, Ni; Z = Al, Si) heusler alloys

    SciTech Connect (OSTI)

    Kourov, N. I. Marchenkov, V. V.; Belozerova, K. A.; Weber, H. W.

    2015-11-15

    The Hall effect and the magnetoresistance of Fe{sub 2}YZ Heusler alloys, where Y = Ti, V, Cr, Mn, Fe, and Ni, are the 3d transition metals and Z = Al and Si are the s, p elements of the third period of the periodic table, are studied at T = 4.2 K in magnetic fields H ≤ 100 kOe. It is shown that, in the high-field limit (H > 10 kOe), the value and the sign of the normal (R{sub 0}) and anomalous (R{sub s}) Hall coefficients change anomalously during transition from paramagnetic (Y = Ti, V) to ferromagnetic (Y = Cr, Mn, Fe, Ni) alloys. These coefficients have different signs for all alloys. Constant R{sub s} in the ferromagnetic alloys is positive, proportional to the residual resistivity ratio (R{sub s} ∝ ρ{sub 0}{sup 3.1}), and inversely proportional to spontaneous magnetization. The magnetoresistance of the alloys is a few percent and has a negative sign. A positive addition to transverse magnetoresistance is only detected in high magnetic fields, H > 10 kOe.

  10. High-cycle fatigue behavior of Ti-5Al-2.5Sn ELI alloy forging at low temperatures

    SciTech Connect (OSTI)

    Ono, Yoshinori; Yuri, Tetsumi; Ogata, Toshio; Demura, Masahiko; Matsuoka, Saburo; Sunakawa, Hideo

    2014-01-27

    High-cycle fatigue properties of Ti-5Al-2.5Sn Extra Low Interstitial (ELI) alloy forging were investigated at low temperatures. The high-cycle fatigue strength at low temperatures of this alloy was relatively low compared with that at ambient temperature. The crystallographic orientation of a facet formed at a fatigue crack initiation site was determined by electron backscatter diffraction (EBSD) method in scanning electron microscope (SEM) to understand the fatigue crack initiation mechanism and discuss on the low fatigue strength at low temperature. Furthermore, in terms of the practical use of this alloy, the effect of the stress ratio (or mean stress) on the high-cycle fatigue properties was evaluated using the modified Goodman diagram.

  11. Growing LaAlO{sub 3}/SrTiO{sub 3} interfaces by sputter deposition

    SciTech Connect (OSTI)

    Dildar, I. M.; Neklyudova, M.; Xu, Q.; Zandbergen, H. W.; Harkema, S.; Boltje, D.; Aarts, J.

    2015-06-15

    Sputter deposition of oxide materials in a high-pressure oxygen atmosphere is a well-known technique to produce thin films of perovskite oxides in particular. Also interfaces can be fabricated, which we demonstrated recently by growing LaAlO{sub 3} on SrTiO{sub 3} substrates and showing that the interface showed the same high degree of epitaxy and atomic order as is made by pulsed laser deposition. However, the high pressure sputtering of oxides is not trivial and number of parameters are needed to be optimized for epitaxial growth. Here we elaborate on the earlier work to show that only a relatively small parameter window exists with respect to oxygen pressure, growth temperature, radiofrequency power supply and target to substrate distance. In particular the sensitivity to oxygen pressure makes it more difficult to vary the oxygen stoichiometry at the interface, yielding it insulating rather than conducting.

  12. Mechanism of surface modification of the Ti-6Al-4V alloy using a gas tungsten arc heat source

    SciTech Connect (OSTI)

    Labudovic, M.; Kovacevic, R.; Kmecko, I.; Khan, T.I.; Blecic, D.; Blecic, Z.

    1999-06-01

    The surface modification of a Ti-6Al-4V alloy using a gas tungsten arc, as a heat source, was studied. The experimental results show that the titanium alloy surface can be melted and nitrided using pure nitrogen or a nitrogen/argon mixture shielding atmosphere. The resolidified surfaces are 0.9 to 1.2-mm thick and contain titanium nitride dendrites, {alpha}-titanium, and {alpha}{double_prime}-titanium (martensite). The average dendrite arm spacing is influenced by the electrode speed. Small titanium nitride dendrites are homogeneously distributed in the resolidified surfaces. The microstructure and phase constitution in the resolidified surfaces were determined and analyzed, and the mechanism of the formation of titanium nitrides is discussed. The results show that the nitriding kinetics obey parabolic laws and are, therefore, controlled by nitrogen diffusion. The nitrogen-concentration depth profiles, calculated using Fick`s second law of diffusion, are compared to experimental nitrogen depth profiles, showing satisfactory agreement.

  13. Understanding the mechanism of conductivity at the LaAlO3/SrTiO3(001) interface

    SciTech Connect (OSTI)

    Chambers, Scott A.

    2011-07-01

    The observation of conductivity at (001)-oriented interfaces of the two band insulators LaAlO3 and SrTiO3 is both fascinating and potentially useful for next-generation electronics. The reigning paradigm to explain the conductivity phenomenon is an electronic reconstruction resulting from the instability created by forming an interface of polar and nonpolar perovskites, leading to the formation of a two-dimensional electron gas. However, the complexities introduced by the strong tendency of the cations to mix across the interface also manifest themselves in the electronic structure, and this mixing gives rise to other ways for the interface to stabilize and become conductive. In this Prospective, arguments for and against these two explanations are explored and strategies for resolving the issue are suggested.

  14. Surface Quality of Ti-6%Al-4%V ELI When Machined Using CVD-Carbide Tools at High Cutting Speed

    SciTech Connect (OSTI)

    Gusri, A. I.; Che Hassan, C. H.; Jaharah, A. G.; Yasir, A.; Zaid, Y.; Yanuar, B.

    2011-01-17

    Machining of Ti-6Al-4V ELI becomes more interested topic due to extremely weight-to-strength ratio and resistance to corrosion at elevated temperature. Quality of machined surface is presented by surface roughness, surface texture and damages of microstructure of titanium alloys. The turning parameters evaluated are cutting speed of 55-95 m/min, feed rate of 0.15-0.35 mm/rev, depth of cut of 0.10-0.20 mm and tool grade of CVD carbide tools. The results show the trend lines of surface roughness value are higher at the initial machining and the surface texture profile has a strong correlation with the feed rate. At the machining condition of cutting speed of 95 m/min, feed rate of 0.35 mm/rev and depth of cut of 0.10 mm produced the with layer with thickness of 2.0 {mu}m.

  15. Investigations on the electronic, structural, magnetic properties related to shape-memory behavior in Ti{sub 2}CoX (X=Al, Ga, In)

    SciTech Connect (OSTI)

    Wei, Xiao-Ping; Chu, Yan-Dong; Sun, Xiao-Wei; E, Yan; Deng, Jian-Bo; Xing, Yong-Zhong

    2015-02-15

    Highlights: • The analysis of phase stability trend is studied for Ti{sub 2}CoX(X = Al, Ga, In). • Ti{sub 2}CoGa is more suitable as shape memory alloy. • Total magnetic moments disappear with a increase of c/a ratio for all systems. • Density of states at the Fermi level are also shown. - Abstract: Using the full-potential local orbital minimum-basis method, we have performed a systematic investigations on the electronic, structural, and magnetic properties related to shape memory applications for Ti{sub 2}CoX (X=Al, Ga, In) alloys. Our results confirm that these alloys are half-metallic ferromagnets with total magnetic moment of 2μ{sub B} per formula unit in austenite phase, and undergo a martensitic transformation at low temperatures. The relative stabilities of the martensitic phases differ considerably between Ti{sub 2}CoX (X=Al, Ga, In). Details of the electronic structures suggest that the differences in hybridizations between the magnetic components are responsible for trends of phase. Quantitative estimates for the energetics and the magnetizations indicate that Ti{sub 2}CoGa is a promising candidate for shape memory applications.

  16. Structural Comparison of n-type and p-type LaAlO3/SrTiO3 Interfaces

    SciTech Connect (OSTI)

    Bell, Christopher

    2011-08-19

    Using a surface x-ray diffraction technique, we investigated the atomic structure of two types of interfaces between LaAlO{sub 3} and SrTiO{sub 3}, that is, p-type (SrO/AlO{sub 2}) and n-type (TiO{sub 2}/LaO) interfaces. Our results demonstrate that the SrTiO{sub 3} in the sample with the n-type interface has a large polarized region, while that with the p-type interface has a limited polarized region. In addition, the atomic intermixing was observed to extend deeper into STO substrate at the n-type interface than at the p-type. These differences result in different degrees of band bending, which likely contributes to the striking difference in electrical conductivity between the two types of interfaces.

  17. Interfacial reactions in epitaxial Al/TiN(111) model diffusion barriers: Formation of an impervious self-limited wurtzite-structure AIN(0001) blocking layer

    SciTech Connect (OSTI)

    Chun, J.-S.; Desjardins, P.; Lavoie, C.; Shin, C.-S.; Cabral, C.; Petrov, I.; Greene, J. E.

    2001-06-15

    Single-crystal TiN(111) layers, 45 nm thick, were grown on MgO(111) by ultrahigh vacuum reactive magnetron sputter deposition in pure N{sub 2} discharges at T{sub s}=700{degree}C. Epitaxial Al(111) overlayers, 160 nm thick, were then deposited at T{sub s}=100{degree}C in Ar without breaking vacuum. Interfacial reactions and changes in bilayer microstructure due to annealing at 620 and 650{degree}C were investigated using x-ray diffraction and transmission electron microscopy (TEM). The interfacial regions of samples annealed at 620{degree}C consist of continuous {approx_equal}7-nm-thick epitaxial wurtzite-structure AlN(0001) layers containing a high density of stacking faults, with {approx_equal}22 nm thick tetragonal Al{sub 3}Ti(112) overlayers. Surprisingly, samples annealed at the higher temperature are more stable against Al{sub 3}Ti formation. TEM analyses of bilayers annealed at 650{degree}C (10{degree}C below the Al melting point!) reveal only the self-limited growth of an {approx_equal}3-nm-thick interfacial layer of perfect smooth epitaxial wurtzite-structure AlN(0001) which serves as an extremely effective deterrent for preventing further interlayer reactions. {copyright} 2001 American Institute of Physics.

  18. Effect of oxygen incorporation on the structure and elasticity of Ti-Al-O-N coatings synthesized by cathodic arc and high power pulsed magnetron sputtering

    SciTech Connect (OSTI)

    Hans, M. Baben, M. to; Music, D.; Ebenhch, J.; Schneider, J. M.; Primetzhofer, D.; Kurapov, D.; Arndt, M.; Rudigier, H.

    2014-09-07

    Ti-Al-O-N coatings were synthesized by cathodic arc and high power pulsed magnetron sputtering. The chemical composition of the coatings was determined by means of elastic recoil detection analysis and energy dispersive X-ray spectroscopy. The effect of oxygen incorporation on the stress-free lattice parameters and Young's moduli of Ti-Al-O-N coatings was investigated by X-ray diffraction and nanoindentation, respectively. As nitrogen is substituted by oxygen, implications for the charge balance may be expected. A reduction in equilibrium volume with increasing O concentration is identified by X-ray diffraction and density functional theory calculations of Ti-Al-O-N supercells reveal the concomitant formation of metal vacancies. Hence, the oxygen incorporation-induced formation of metal vacancies enables charge balancing. Furthermore, nanoindentation experiments reveal a decrease in elastic modulus with increasing O concentration. Based on ab initio data, two causes can be identified for this: First, the metal vacancy-induced reduction in elasticity; and second, the formation of, compared to the corresponding metal nitride bonds, relatively weak Ti-O and Al-O bonds.

  19. Project Summary-TES-SNL.doc. (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Project Summary-TES-SNL.doc. Citation Details In-Document Search Title: Project Summary-TES-SNL.doc. Abstract not provided. Authors: Siegel, Nathan Phillip Publication Date: ...

  20. Al

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    on the way to the drip line .... 31 Al 28 Mg 32 Si 12 B + 18 O 30 Al* (-pn) 28 Mg 15 C + 18 O 33 Si* (-pn) 31 Al 16 N + 18 O 34 P* (-pn) 32 Si 15 C 10 7 s...

  1. Microstructural characterization and mechanical properties of high power ultrasonic spot welded aluminum alloy AA6111–TiAl6V4 dissimilar joints

    SciTech Connect (OSTI)

    Zhang, C.Q. Robson, J.D.; Ciuca, O.; Prangnell, P.B.

    2014-11-15

    Aluminum alloy AA6111 and TiAl6V4 dissimilar alloys were successfully welded by high power ultrasonic spot welding. No visible intermetallic reaction layer was detected in as-welded AA6111/TiAl6V4 welds, even when transmission electron microscopy was used. The effects of welding time and natural aging on peak load and fracture energy were investigated. The peak load and fracture energy of welds increased with an increase in welding time and then reached a plateau. The lap shear strength (peak load) can reach the same level as that of similar Al–Al joints. After natural aging, the fracture mode of welds transferred from ductile fracture of the softened aluminum to interfacial failure due to the strength recovery of AA6111. - Highlights: • Dissimilar Al/Ti welds were produced by high power ultrasonic spot welding. • No visible intermetallic reaction layer was detected on weld interface. • The lap shear strength can reach the same level as that of similar Al–Al joints. • The fracture mode becomes interfacial failure after natural aging.

  2. Dynamic recrystallization behavior of an as-cast TiAl alloy during hot compression

    SciTech Connect (OSTI)

    Li, Jianbo; Liu, Yong; Wang, Yan; Liu, Bin; He, Yuehui

    2014-11-15

    High temperature compressive deformation behaviors of as-cast Ti–43Al–4Nb–1.4W–0.6B alloy were investigated at temperatures ranging from 1050 °C to 1200 °C, and strain rates from 0.001 s{sup −1} to 1 s{sup −1}. Electron back scattered diffraction technique, scanning electron microscopy and transmission electron microscopy were employed to investigate the microstructural evolutions and nucleation mechanisms of the dynamic recrystallization. The results indicated that the true stress–true strain curves show a dynamic flow softening behavior. The dependence of the peak stress on the deformation temperature and the strain rate can well be expressed by a hyperbolic-sine type equation. The activation energy decreases with increasing the strain. The size of the dynamically recrystallized β grains decreases with increasing the value of the Zener–Hollomon parameter (Z). When the flow stress reaches a steady state, the size of β grains almost remains constant with increasing the deformation strain. The continuous dynamic recrystallization plays a dominant role in the deformation. In order to characterize the evolution of dynamic recrystallization volume fraction, the dynamic recrystallization kinetics was studied by Avrami-type equation. Besides, the role of β phase and the softening mechanism during the hot deformation was also discussed in details. - Highlights: • The size of DRXed β grains decreases with increasing the value of the Z. • The CDRX plays a dominant role in the deformation. • The broken TiB{sub 2} particles can promote the nucleation of DRX.

  3. ALD TiO2-Al2O3 Stack: An Improved Gate Dielectrics on Ga-polar GaN MOSCAPs

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wei, Daming; Edgar, James H.; Briggs, Dayrl P.; Srijanto, Bernadeta R.; Retterer, Scott T.; Meyer, III, Harry M.

    2014-10-15

    This research focuses on the benefits and properties of TiO2-Al2O3 nano-stack thin films deposited on Ga2O3/GaN by plasma-assisted atomic layer deposition (PA-ALD) for gate dielectric development. This combination of materials achieved a high dielectric constant, a low leakage current, and a low interface trap density. Correlations were sought between the films’ structure, composition, and electrical properties. The gate dielectrics were approximately 15 nm thick and contained 5.1 nm TiO2, 7.1 nm Al2O3 and 2 nm Ga2O3 as determined by spectroscopic ellipsometry. The interface carbon concentration, as measured by x-ray photoelectron spectroscopy (XPS) depth profile, was negligible for GaN pretreated bymore » thermal oxidation in O2 for 30 minutes at 850°C. The RMS roughness slightly increased after thermal oxidation and remained the same after ALD of the nano-stack, as determined by atomic force microscopy. The dielectric constant of TiO2-Al2O3 on Ga2O3/GaN was increased to 12.5 compared to that of pure Al2O3 (8~9) on GaN. In addition, the nano-stack's capacitance-voltage (C-V) hysteresis was small, with a total trap density of 8.74 × 1011 cm-2. The gate leakage current density (J=2.81× 10-8 A/cm2) was low at +1 V gate bias. These results demonstrate the promising potential of plasma ALD deposited TiO2/Al2O3 for serving as the gate oxide on Ga2O3/GaN based MOS devices.« less

  4. Growth and transport properties of epitaxial lattice matched half Heusler CoTiSb/InAlAs/InP(001) heterostructures

    SciTech Connect (OSTI)

    Kawasaki, Jason K.; Johansson, Linda I. M.; Schultz, Brian D.; Palmstrm, Chris J.

    2014-01-13

    We demonstrate the integration of the lattice matched single crystal epitaxial Half Heusler compound CoTiSb with In{sub 0.52}Al{sub 0.48}As/InP(001) heterostructures using molecular beam epitaxy. CoTiSb belongs to the subset of Half Heusler compounds that is expected to be semiconducting, despite being composed entirely of metallic constituents. The lattice matching and epitaxial alignment of the CoTiSb films were confirmed by reflection high energy electron diffraction and X-ray diffraction. Temperature dependent transport measurements indicate semiconducting-like behavior, with a room temperature Hall mobility of 530 cm{sup 2}/Vs and background Hall carrier density of 9.0??10{sup 17}?cm{sup ?3}, which is comparable to n-Si with similar carrier density. Below 100?K, the films show a large negative magnetoresistance, and possible origins of this negative magnetoresistance are discussed.

  5. Interface structure of SrTiO{sub 3}/LaAlO{sub 3} at elevated temperatures studied in situ by synchrotron x rays

    SciTech Connect (OSTI)

    Vonk, V.; Huijben, M.; Driessen, K. J. I.; Brinkman, A.; Harkema, S.; Tinnemans, P.; Graafsma, H.

    2007-06-15

    The atomic interface structure between SrTiO{sub 3} and LaAlO{sub 3} was studied at elevated temperatures employing in situ surface x-ray diffraction. The results at 473 K indicate that the lattice distorts significantly in two ways. First, the interatomic distances between the cations across the interface become as large as 4.03(2) A. Second, the TiO{sub 6} octahedra at the interface contract their principal axis along the surface normal considerably and the Ti displaces off center. These distortions can be ascribed to the charge inbalance introduced by the change in atomic species across the interface and to a Jahn-Teller effect. The latter distortion suggests the presence of extra electrons at the interface, which is important for understanding the electronic properties of this system.

  6. Analysis of Wear Mechanisms in Low Friction, Nanocomposite AlMgB14-TiB2 Coatings

    SciTech Connect (OSTI)

    Cook, Bruce A; Harringa, J; Anderegg, A; Russell, A M; Qu, Jun; Blau, Peter Julian; Higdon, Clifton; Elmoursi, Alaa A

    2010-01-01

    Recent developments in coating science and technology offer new opportunities to enhance the energy-efficiency and performance of industrial machinery such as hydraulic fluid pumps and motors. The lubricated friction and wear characteristics of two wear-resistant coatings, diamond-like carbon and a nanocomposite material based on AlMgB{sub 14}-50 vol.% TiB{sub 2}, were compared in pin-on-disk tribotests using Mobil DTE-24{trademark} oil as the lubricant. In each case, the pins were fixed 9.53 mm diameter spheres of AISI 52100 steel, the load was 10 N, and the speed 0.5 m/s in all tests. Average steady-state friction coefficient values of 0.10 and 0.08 were measured for the DLC and nanocomposite, respectively. The coatings and their 52100 steel counterfaces were analyzed after the tests by X-ray photoelectron and Auger spectroscopy for evidence of material transfer or tribo-chemical reactions. The low-friction behavior of the boride nanocomposite coating is due to the formation of lubricative boric acid, B(OH){sub 3}. In contrast, the low-friction behavior of the DLC coating is related to the relatively low dielectric constant of the oil-based lubricant, leading to desorption of surface hydrogen from the coating.

  7. Wear Mechanism of Chemical Vapor Deposition (CVD) Carbide Insert in Orthogonal Cutting Ti-6Al-4V ELI at High Cutting Speed

    SciTech Connect (OSTI)

    Gusri, A. I.; Che Hassan, C. H.; Jaharah, A. G.

    2011-01-17

    The performance of Chemical Vapor Deposition (CVD) carbide insert with ISO designation of CCMT 12 04 04 LF, when turning titanium alloys was investigated. There were four layers of coating materials for this insert i.e.TiN-Al2O3-TiCN-TiN. The insert performance was evaluated based on the insert's edge resistant towards the machining parameters used at high cutting speed range of machining Ti-6Al-4V ELI. Detailed study on the wear mechanism at the cutting edge of CVD carbide tools was carried out at cutting speed of 55-95 m/min, feed rate of 0.15-0.35 mm/rev and depth of cut of 0.10-0.20 mm. Wear mechanisms such as abrasive and adhesive were observed on the flank face. Crater wear due to diffusion was also observed on the rake race. The abrasive wear occurred more at nose radius and the fracture on tool were found at the feed rate of 0.35 mm/rev and the depth of cut of 0.20 mm. The adhesion wear takes place after the removal of the coating or coating delaminating. Therefore, adhesion or welding of titanium alloy onto the flank and rake faces demonstrates a strong bond at the workpiece-tool interface.

  8. Oxynitrided Surface Layer Produced On Ti6Al4V Titanium Alloy Under Low Temperature Glow Discharge Conditions For Medical Applications

    SciTech Connect (OSTI)

    Wierzchon, T.; Ossowski, M.; Borowski, T.; Morgiel, J.; Czarnowska, E.

    2011-01-17

    In spite that titanium oxides increase biocompatibility of titanium implants but their functional life is limited due to the problems arising from brittles and metalosis. Therefore technology, that allow to produce composite surface layer with controlled microstructure, chemical and phase composition and surface morphology on titanium alloy and eliminates the oxides disadvantages has been existing till now is searched. The requirements of titanium and its alloys implants can be fulfill by the low-temperature glow discharge assisted oxynitriding.The paper describes the surface layer of TiO{sub 2}+TiN+Ti{sub 2}N+{alpha}Ti(N) type produced at temperature 680 deg. C that preserves mechanical properties of titanium alloy Ti6Al4V. Characteristics of produced diffusion multi-phase surface layers in range of phase composition, microstructure (SEM, TEM, XRD) and its properties, such as frictional wear resistance are presented. The biological properties in dependency to the applied sterilization method are also analyzed.Properties of produced surface layers are discussed with reference to titanium alloy. The obtained data show that produced surface layers improves titanium alloy properties both frictional wear and biological. Preliminary in vitro examinations show good biocompatibility and antithrombogenic properties.

  9. Improvement in performance of electrically tunable devices based on nonlinear dielectric SrTiO{sub 3} using a homoepitaxial LaAlO{sub 3} interlayer

    SciTech Connect (OSTI)

    Jia, Q.X.; Findikoglu, A.T.; Reagor, D.; Lu, P.

    1998-08-01

    Improved structural and dielectric properties of nonlinear dielectric SrTiO{sub 3} thin films on LaAlO{sub 3} substrates were accomplished by incorporating a {ital homoepitaxial} LaAlO{sub 3} interlayer between the substrate and the dielectric film. Using this interlayer, the quality factor of SrTiO{sub 3} films with high-temperature superconducting YBa{sub 2}Cu{sub 3}O{sub 7{minus}x} electrodes on LaAlO{sub 3} substrates was improved by more than 50{percent} at 4.2 GHz and 4 K. This improvement, combined with no change in nonlinearity, led to greater than a 50{percent} enhancement of the finesse factor (defined as the product of the quality factor and the fractional shift resonant frequency) for the coplanar waveguide microwave resonators. The reduced planar defect density in the SrTiO{sub 3} films was attributed to this improvement. {copyright} {ital 1998 American Institute of Physics.}

  10. Ferroelectric, and piezoelectric properties of BaTi{sub 1−x}Al{sub x}O{sub 3}, 0 ≤ x ≤ 0.015

    SciTech Connect (OSTI)

    Ali, Ahmed I.; Hassen, A.; Khang, Nguyen Cao; Kim, Y. S.

    2015-09-15

    Single phase polycrystalline samples of BaTi{sub 1−x}Al{sub x}O{sub 3}, 0 ≤ x ≤ 0.015, have been prepared by a conventional powder processing method. The Rietveld refinements of X- ray powder diffraction patterns at room temperature indicate that the samples crystallize in tetragonal structure with group symmetry P4mm. Because of the oxygen vacancies, the volume of the unit cell increases with increasing x. Field emission scanning electron microscopy revealed that the particle size of pure BTO ceramics was affected by the Al content. Dielectric, ferroelectric and piezoelectric properties of pure BTO as well as Al-doped BTO were studied. It was found that the dielectric permittivity (ε′) increases significantly with increasing x while the transition from ferroelectric phase to a paraelectric phase changes slightly. The Curie-Weiss law is verified over a wide temperature range. Both ferroelectric and piezoelectric properties of BTO are enhanced by the substitution of Ti{sup 4+} by Al{sup 3+} ions. Piezoelectric strains of Al-doped BTO showed a suitable behavior for application compared with that of pure BTO compound. Finally, the results obtained in this work are discussed and compared with those for similar materials.

  11. Substitution studies of Mn and Fe in Ln{sub 6}W{sub 4}Al{sub 43} (Ln=Gd, Yb) and the structure of Yb{sub 6}Ti{sub 4}Al{sub 43}

    SciTech Connect (OSTI)

    Treadwell, LaRico J.; Watkins-Curry, Pilanda; McAlpin, Jacob D.; Prestigiacomo, Joseph; Stadler, Shane; Chan, Julia Y.

    2014-02-15

    The synthesis and characterization of Mn- and Fe-substituted Ln{sub 6}W{sub 4}Al{sub 43} (Ln=Gd, Yb) and Yb{sub 6}Ti{sub 4}Al{sub 43} are reported. The compounds adopt the Ho{sub 6}Mo{sub 4}Al{sub 43} structure type with lattice parameters of a∼11 Å and c∼17.8 Å with structural site preferences for Mn and Fe. The magnetization of Yb{sub 6}W{sub 4}Al{sub 43} is sensitive to Mn and Fe doping, which is evident by an increase in the field dependent magnetization. Gd{sub 6}W{sub 4}Al{sub 43}, Gd{sub 6}W{sub 4}Al{sub 42.31(11)}Mn{sub 0.69(11)}, and Gd{sub 6}W{sub 4}Al{sub 41.69(12)}Fe{sub 1.30(12)} order antiferromagnetically in the ab- and c-directions at 15, 14, and 13 K, respectively, with positive Weiss constants, suggesting the presence of ferromagnetic exchange interactions. Anisotropic magnetization data of Gd{sub 6}W{sub 4}Al{sub 43−y}T{sub y} (T=Mn, Fe) analogs are discussed. - Graphical abstract: The magnetic susceptibility of Ln{sub 6}W{sub 4−x}Al{sub 43−y}T{sub x+y} (Ln = Gd, Yb; T= Mn, Fe). Display Omitted - Highlights: • Single crystals of Ln{sub 6}W{sub 4−x}Al{sub 43−y}T{sub x+y} were grown with Al-flux. • Anisotropic magnetic behavior were determined on single crystals. • Gd{sub 6}W{sub 4−x}Al{sub 43−y}T{sub x+y} (T=Mn, Fe) analogs order antiferromagnetically.

  12. Quantum oscillations and subband properties of the two-dimensional electron gas at the LaAlO{sub 3}/SrTiO{sub 3} interface

    SciTech Connect (OSTI)

    McCollam, A. Guduru, V. K.; Zeitler, U.; Maan, J. C.; Wenderich, S.; Kruize, M. K.; Molegraaf, H. J. A.; Huijben, M.; Koster, G.; Blank, D. H. A.; Rijnders, G.; Brinkman, A.; Hilgenkamp, H.

    2014-02-01

    We have performed high field magnetotransport measurements to investigate the interface electron gas in a high mobility SrTiO{sub 3}/SrCuO{sub 2}/LaAlO{sub 3}/SrTiO{sub 3} heterostructure. Shubnikov-de Haas oscillations reveal several 2D conduction subbands with carrier effective masses of 0.9m{sub e} and 2m{sub e}, quantum mobilities of order 2000 cm{sup 2}/V s, and band edges only a few millielectronvolts below the Fermi energy. Measurements in tilted magnetic fields confirm the 2D character of the electron gas, and show evidence of inter-subband scattering.

  13. The distribution alloying elements in alnico 8 and 9 magnets: Site preference of ternary Ti, Fe, Co, and Ni additions in DO{sub 3} Fe{sub 3}Al, Co{sub 3}Al, and Ni{sub 3}Al based intermetallic phases

    SciTech Connect (OSTI)

    Samolyuk, G. D.; Stocks, G. M.; Újfalussy, B.

    2014-11-07

    Recently, interest in alnico magnetic alloys has been rekindled due to their potential to substitute for rare-earth based permanent magnets provided modest improvements in their coercivity can be achieved without loss of saturation magnetization. Recent experimental studies have indicated that atomic and magnetic structure of the two phases (one AlNi-based, the other FeCo-based) that comprise these spinodally decomposed alloy is not as simple as previously thought. A key issue that arises is the distribution of Fe, Co, and Ti within the AlNi-based matrix phase. In this paper, we report the results of first-principles calculations of the site preference of ternary alloying additions in DO{sub 3} Fe{sub 3}Al, Co{sub 3}Al, and Ni{sub 3}Al alloys, as models for the aluminide phase. For compound compositions that are Al rich, which correspond to experimental situation, Ti and Fe are found to occupy the α sites, while Co and Ni prefer the γ sites of the DO{sub 3} lattice. An important finding is that the magnetic moments of transition metals in Fe{sub 3}Al and Co{sub 3}Al are ordered ferromagnetically, whereas the Ni{sub 3}Al were found to be nonmagnetic unless the Fe or Co is added as a ternary element.

  14. The distribution alloying elements in alnico 8 and 9 magnets: Site preference of ternary Ti, Fe, Co, and Ni additions in DO3 Fe3Al, Co3Al, and Ni3Al based intermetallic phases

    SciTech Connect (OSTI)

    Samolyuk, G. D.; Újfalussy, B.; Stocks, G. M.

    2014-11-07

    Recently, interest in alnico magnetic alloys has been rekindled due to their potential to substitute for rare-earth based permanent magnets provided modest improvements in their coercivity can be achieved without loss of saturation magnetization. Recent experimental studies have indicated that atomic and magnetic structure of the two phases (one AlNi-based, the other FeCo-based) that comprise these spinodally decomposed alloy is not as simple as previously thought. A key issue that arises is the distribution of Fe, Co and Ti within the AlNi-based matrix phase. In our paper we report the results of first-principles calculations of the site preference of ternary alloying additions in DO3 Fe3Al, Co3Al and Ni3Al alloys, as models for the aluminide phase. For compound compositions that are Al rich, which corresponds to experimental situation, Ti and Fe are found to occupy the sites, while Co and Ni prefer the sites of the DO3 lattice. Finally, an important finding is that the magnetic moments of transition metals in Fe3Al and Co3Al are ordered ferromagnetically, whereas the Ni3Al were found to be nonmagnetic unless the Fe or Co are added as a ternary element.

  15. Magneto-transport study of top- and back-gated LaAlO{sub 3}/SrTiO{sub 3} heterostructures

    SciTech Connect (OSTI)

    Liu, W. Gariglio, S.; Fête, A.; Li, D.; Boselli, M.; Stornaiuolo, D.; Triscone, J.-M.

    2015-06-01

    We report a detailed analysis of magneto-transport properties of top- and back-gated LaAlO{sub 3}/SrTiO{sub 3} heterostructures. Efficient modulation in magneto-resistance, carrier density, and mobility of the two-dimensional electron liquid present at the interface is achieved by sweeping top and back gate voltages. Analyzing those changes with respect to the carrier density tuning, we observe that the back gate strongly modifies the electron mobility while the top gate mainly varies the carrier density. The evolution of the spin-orbit interaction is also followed as a function of top and back gating.

  16. Excellent Passivation and Low Reflectivity Al2O3/TiO2 Bilayer Coatings for n-Wafer Silicon Solar Cells: Preprint

    SciTech Connect (OSTI)

    Lee, B. G.; Skarp, J.; Malinen, V.; Li, S.; Choi, S.; Branz, H. M.

    2012-06-01

    A bilayer coating of Al2O3 and TiO2 is used to simultaneously achieve excellent passivation and low reflectivity on p-type silicon. This coating is targeted for achieving high efficiency n-wafer Si solar cells, where both passivation and anti-reflection (AR) are needed at the front-side p-type emitter. It could also be valuable for front-side passivation and AR of rear-emitter and interdigitated back contact p-wafer cells. We achieve high minority carrier lifetimes {approx}1 ms, as well as a nearly 2% decrease in absolute reflectivity, as compared to a standard silicon nitride AR coating.

  17. Engineering two-dimensional superconductivity and Rashba spin–orbit coupling in LaAlO3/SrTiO3 quantum wells by selective orbital occupancy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Herranz, Gervasi; Singh, Gyanendra; Bergeal, Nicolas; Jouan, Alexis; Lesueur, Jérôme; Gázquez, Jaume; Varela, María; Scigaj, Mateusz; Dix, Nico; Sánchez, Florencio; et al

    2015-01-13

    We find the discovery of two-dimensional electron gases (2DEGs) at oxide interfaces—involving electrons in narrow d-bands—has broken new ground, enabling the access to correlated states that are unreachable in conventional semiconductors based on s- and p- electrons. There is a growing consensus that emerging properties at these novel quantum wells—such as 2D superconductivity and magnetism—are intimately connected to specific orbital symmetries in the 2DEG sub-band structure. Here we show that crystal orientation allows selective orbital occupancy, disclosing unprecedented ways to tailor the 2DEG properties. By carrying out electrostatic gating experiments in ​LaAlO3/​SrTiO3 wells of different crystal orientations, we show thatmore » the spatial extension and anisotropy of the 2D superconductivity and the Rashba spin–orbit field can be largely modulated by controlling the 2DEG sub-band filling. Such an orientational tuning expands the possibilities for electronic engineering of 2DEGs at ​LaAlO3/​SrTiO3 interfaces.« less

  18. Instability, intermixing and electronic structure at the epitaxial LaAlO3/SrTiO3(001) heterojunction

    SciTech Connect (OSTI)

    Chambers, Scott A.; Engelhard, Mark H.; Shutthanandan, V.; Zhu, Zihua; Droubay, Timothy C.; Qiao, Liang; Sushko, P. V.; Feng, Tian; Lee, Hang Don; Gustafsson, Torgny; Garfunkel, Eric; Shah, A.B,; Zuo, J. M.; Ramasse, Q. M.

    2010-10-18

    The question of stability against diffusional mixing at the prototypical LaAlO3/SrTiO3(001) interface is explored using a multi-faceted experimental and theoretical approach. We combine analytical methods with a range of sensitivities to elemental concentrations and spatial separations to investigate interfaces grown using onaxis pulsed laser deposition. We also employ computational modeling based on the density function theory as well as classical force fields to explore the energetic stability of a wide variety of intermixed atomic configurations relative to the idealized, atomically abrupt model. Statistical analysis of the calculated energies for the various configurations is used to elucidate the relative thermodynamic stability of intermixed and abrupt configurations. We find that on both experimental and theoretical fronts, the tendency toward intermixing is very strong. We have also measured and calculated key electronic properties such as potential energy gradients and valence band discontinuity at the interface. We find no measurable electric field in either the LaAlO3 or SrTiO3, and that the valence band offset is near zero, partitioning the band discontinuity almost entirely to the conduction band edge. Significantly, we find it is not possible to account for these electronic properties theoretically without including extensive intermixing in our physical model of the interface. The atomic configurations which give the greatest electrostatic stability are those that eliminate the interface dipole by intermixing, calling into question the conventional explanation for conductivity at this interface electronic reconstruction. Rather, evidence is presented for La indiffusion and doping of the SrTiO3 below the interface as being the cause of the observed conductivity.

  19. Defect models for sintering and densification of Al/sub 2/O/sub 3/:Ti and Al/sub 2/O/sub 3/:Zr

    SciTech Connect (OSTI)

    Kroger, F.A.

    1984-06-01

    A defect model proposed to explain the effect of titanium doping on the rate of sintering of Al/sub 2/O/sub 3/ is revised to fit the oxidizing conditions of the experiments. The model accounts for the observed change in sintering rate by a change from rate limitation by ions to rate limitation by electrons, but requires the presence of an unusually large concentration of acceptor impurities in the material. Models similar to the ones originally proposed account for the rate of densification of Al/sub 2/O/sub 3/:Zr by hot-pressing in vacuo, provided it is extended by including electronics defects.

  20. Quasi-two-dimensional electron gas at the interface of γ-Al{sub 2}O{sub 3}/SrTiO{sub 3} heterostructures grown by atomic layer deposition

    SciTech Connect (OSTI)

    Ngo, Thong Q.; McDaniel, Martin D.; Ekerdt, John G.; Goble, Nicholas J.; Gao, Xuan P. A.; Posadas, Agham; Kormondy, Kristy J.; Demkov, Alexander A.; Lu, Sirong; Jordan-Sweet, Jean; Smith, David J.

    2015-09-21

    We report the formation of a quasi-two-dimensional electron gas (2-DEG) at the interface of γ-Al{sub 2}O{sub 3}/TiO{sub 2}-terminated SrTiO{sub 3} (STO) grown by atomic layer deposition (ALD). The ALD growth of Al{sub 2}O{sub 3} on STO(001) single crystal substrates was performed at temperatures in the range of 200–345 °C. Trimethylaluminum and water were used as co-reactants. In situ reflection high energy electron diffraction, ex situ x-ray diffraction, and ex situ cross-sectional transmission electron microscopy were used to determine the crystallinity of the Al{sub 2}O{sub 3} films. As-deposited Al{sub 2}O{sub 3} films grown above 300 °C were crystalline with the γ-Al{sub 2}O{sub 3} phase. In situ x-ray photoelectron spectroscopy was used to characterize the Al{sub 2}O{sub 3}/STO interface, indicating that a Ti{sup 3+} feature in the Ti 2p spectrum of STO was formed after 2–3 ALD cycles of Al{sub 2}O{sub 3} at 345 °C and even after the exposure to trimethylaluminum alone at 300 and 345 °C. The interface quasi-2-DEG is metallic and exhibits mobility values of ∼4 and 3000 cm{sup 2} V{sup −1} s{sup −1} at room temperature and 15 K, respectively. The interfacial conductivity depended on the thickness of the Al{sub 2}O{sub 3} layer. The Ti{sup 3+} signal originated from the near-interfacial region and vanished after annealing in an oxygen environment.

  1. Potential-well depth at amorphous-LaAlO{sub 3}/crystalline-SrTiO{sub 3} interfaces measured by optical second harmonic generation

    SciTech Connect (OSTI)

    De Luca, Gabriele; Rubano, Andrea; Gennaro, Emiliano di; Khare, Amit; Granozio, Fabio Miletto; Uccio, Umberto Scotti di; Marrucci, Lorenzo; Paparo, Domenico

    2014-06-30

    By a combination of optical second harmonic generation and transport measurements, we have investigated interfaces formed by either crystalline or amorphous thin films of LaAlO{sub 3} grown on TiO{sub 2}-terminated SrTiO{sub 3}(001) substrates. Our approach aims at disentangling the relative role of intrinsic and extrinsic doping mechanisms in the formation of the two-dimensional electron gas. The different nature of the two mechanisms is revealed when comparing the sample response variation as a function of temperature during annealing in air. However, before the thermal treatment, the two types of interfaces show almost the same intensity of the second harmonic signal, provided the overlayer thickness is the same. As we will show, the second harmonic signal is proportional to the depth of the potential well confining the charges at the interface. Therefore, our result demonstrates that this depth is about the same for the two different material systems. This conclusion supports the idea that the electronic properties of the two-dimensional electron gas are almost independent of the doping mechanism of the quantum well.

  2. Enhancing mid-infrared spectral response at the LaAlO{sub 3}/SrTiO{sub 3} interface by magnetic field

    SciTech Connect (OSTI)

    Feng, Xin; Zhao, Kun Xi, Jian-Feng; Xiang, Wen-Feng; Lu, Zhi-Qing; Sun, Qi; Wu, Shi-Xiang; Ni, Hao

    2014-12-15

    Many unexpected properties have been found in the LaAlO{sub 3}/SrTiO{sub 3} heterostructure, but the interaction of the many ground states at its interface remains unclear. Here, we demonstrate an optical property of this n-type heterostructure where the mid-infrared spectral responsivity at the interface is enhanced by an external magnetic field. The field intensity ranged from 0.8 to 6 kOe at a low temperature (19 K) as measured with our spectral response measurement system. Two spectral peaks related to the spin-orbit coupling effect were also observed at wavelengths 2400 nm and 3700 nm. The intriguing phenomena relate to changes in the crystallographic structure and subband structure at the interface.

  3. Role of oxygen vacancies in magnetic properties of LaAlO{sub 3}/SrTiO{sub 3} interface

    SciTech Connect (OSTI)

    Mohanta, N.; Taraphder, A.

    2014-04-24

    The interface of two band-insulators SrTiO{sub 3} and LaAlO{sub 3} exhibits a highly conducting two-dimensional electron gas which shows low-temperature superconductivity, ferromagnetism and many other novel properties. Several studies reveal that the oxygen vacancies at the interface have strong influence on the electronic and magnetic properties of the interface electrons. Here, we develop an insight into the effects of oxygen vacancies on the magnetic properties of the system; the oxygen vacancies help in establishing ferromagnetism which competes with superconductivity at low temperatures. Simulated Monte-Carlo annealing suggests an ordering of the oxygen vacant sites and sheds light on the experimental observation of the quenching of magnetic moment on annealing. A possible explanation for the coexistence of superconductivity and ferromagnetism is also discussed.

  4. Structural and subband changes at the LaAlO{sub 3}/SrTiO{sub 3} interface investigated by two-dimensional correlation spectroscopy

    SciTech Connect (OSTI)

    Feng, Xin; Zhao, Kun Zhan, Hong-Lei; Xiang, Wen-Feng; Lu, Zhi-Qing; Xiao, Li-Zhi

    2015-06-15

    The interplay among many ground states in correlated electron materials, especially at the LaAlO{sub 3}/SrTiO{sub 3} interface is central in deeply understanding the physical characteristics and improving further applications of these materials. Here, we use two-dimensional infrared correlation spectroscopy to study the influence of magnetic fields and temperature on the mid-infrared spectral responsivity of the interface. The magnetic field plays the main role at temperatures below the transition temperature, T{sub C}. Two additional spectral peaks were identified at wavelengths of 2800 nm and 3400 nm, when compared with our prior studies. All of these response bands are related to the spin-orbit coupling effect and crystal structure changes. Detailed structural and subband changes in the interface are also investigated.

  5. Effects of Reduction Temperature and Metal-Support Interactions on the Catalytic Activity of Pt/g-Al2O3 and Pt/TiO2 for the Oxidation of CO in the Presence and Absence of H2.

    SciTech Connect (OSTI)

    Alexeev,O.; Chin, S.; Engelhard, M.; Ortiz-Soto, L.; Amiridis, M.

    2005-01-01

    TiO2- and -Al2O3-supported Pt catalysts were characterized by HRTEM, XPS, EXAFS, and in situ FTIR spectroscopy after activation at various conditions, and their catalytic properties were examined for the oxidation of CO in the absence and presence of H2 (PROX). When {gamma}-Al{sub 2}O{sub 3} was used as the support, the catalytic, electronic, and structural properties of the Pt particles formed were not affected substantially by the pretreatment conditions. In contrast, the surface properties and catalytic activity of Pt/TiO2 were strongly influenced by the pretreatment conditions. In this case, an increase in the reduction temperature led to higher electron density on Pt, altering its chemisorptive properties, weakening the Pt-CO bonds, and increasing its activity for the oxidation of CO. The in situ FTIR data suggest that both the terminal and bridging CO species adsorbed on fully reduced Pt are active for this reaction. The high activity of Pt/TiO2 for the oxidation of CO can also be attributed to the ability of TiO2 to provide or stabilize highly reactive oxygen species at the metal-support interface. However, such species appear to be more reactive toward H{sub 2} than CO. Consequently, Pt/TiO{sub 2} shows substantially lower selectivities toward CO oxidation under PROX conditions than Pt/{gamma}-Al{sub 2}O{sub 3}.

  6. Effects of Reduction Temperature and Metal-support Interactions on the Catalytic Activity of Pt/γ-Al2O3 and Pt/TiO2 for the Oxidation of CO in the Presence and Absence of H2

    SciTech Connect (OSTI)

    Alexeev, Oleg S.; Chin, Soo Yin; Engelhard, Mark H.; Ortiz-Soto, Lorna; Amiridis, Michael D.

    2005-12-15

    TiO2- and ?-Al2O3-supported Pt catalysts were characterized by HRTEM, XPS, EXAFS, and in-situ FTIR after activation at various conditions and their catalytic properties were examined for the oxidation of CO in the absence and presence of H2 (PROX). When ?-Al2O3 was used as the support, the catalytic, electronic, and structural properties of the Pt particles formed were not affected substantially by the pretreatment conditions. In contrast, the surface properties and catalytic activity of Pt/TiO2 were strongly influenced by the pretreatment conditions. In this case, an increase in the reduction temperature led to higher electron density on Pt, altering its chemisorptive properties, weakening the Pt-CO bonds, and increasing its activity for the oxidation of CO. The in-situ FTIR data suggest that both the terminal and bridging CO species adsorbed on fully reduced Pt are active for this reaction. The high activity of Pt/TiO2 for the oxidation of CO can also be attributed to the ability of TiO2 to provide or stabilize highly reactive oxygen species at the metal-support interface. However, such species appear to be more reactive towards H2 than CO. Consequently, Pt/TiO2 shows substantially lower selectivities towards CO oxidation under PROX conditions than Pt/?-Al2O3.

  7. Technology Potential of Thermal Energy Storage (TES) Systems in Federal Facilities

    SciTech Connect (OSTI)

    Chvala, William D.

    2001-07-31

    This document presents the findings of a technology market assessment for thermal energy storage (TES) in space cooling applications. The potential impact of TES in Federal facilities is modeled using the Federal building inventory with the appropriate climatic and energy cost data. In addition, this assessment identified acceptance issues and major obstacles through interviews with energy services companies (ESCOs), TES manufacturers, and Federal facility staff.

  8. U.S. CHP Installations Incorporating Thermal Energy Storage (TES) and/or

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Turbine Inlet Cooling (TIC), September 2003 | Department of Energy CHP Installations Incorporating Thermal Energy Storage (TES) and/or Turbine Inlet Cooling (TIC), September 2003 U.S. CHP Installations Incorporating Thermal Energy Storage (TES) and/or Turbine Inlet Cooling (TIC), September 2003 This 2003 chart of U.S. CHP installations incorporating Thermal Energy Storage (TES) and/or Turbine Inlet Cooling (TIC) was prepared by the Cool Solutions Company of Lisle, Illinois, for UT-Battelle,

  9. Tunability of conduction at the LaAlO{sub 3}/SrTiO{sub 3} heterointerface: Thickness and compositional studies

    SciTech Connect (OSTI)

    Breckenfeld, E.; Bronn, N.; Mason, N.; Martin, L. W.

    2014-09-22

    The role of chemistry, film thickness, and oxygen pressure in influencing the electrical and thermal transport properties of LaAlO{sub 3}/SrTiO{sub 3} heterointerfaces is explored. Unit-cell precise growth was accomplished for films between 3 and 160 unit cells thick using reflection high-energy electron diffraction-assisted pulsed-laser deposition. Subsequent temperature-dependent studies of electrical resistivity reveal three important observations: (1) by tuning the laser fluence, we can systematically tune the interfacial conductance in a step-wise manner in this system, (2) all films exhibit a critical thickness of 34 unit cells for the onset of conduction, and (3) the nature of the conductance is highly influenced by the stoichiometry of the LaAlO{sub 3} film with La-deficient samples showing dramatic changes with thickness, while stoichiometric and La-excess films show little dependence. Time-domain thermoreflectance studies show a diminished interfacial thermal conductance for the La-deficient films when compared to La-excess and stoichiometric films, suggesting that the interfacial conductance is more influenced by extrinsic factors such as oxygen deficiency.

  10. Band alignment of epitaxial SrTiO3 thin films with (LaAlO3)0.3-(Sr2AlTaO6)0.7 (001)

    SciTech Connect (OSTI)

    Comes, Ryan B.; Xu, Peng; Jalan, Bharat; Chambers, Scott A.

    2015-09-28

    SrTiO3 (STO) epitaxial thin films and heterostructures are of considerable interest due to the wide range of functionalities they exhibit. The alloy perovskite (LaAlO3)0.3-(Sr2AlTaO6)0.7 (LSAT) is commonly used as a substrate for these material structures due to its structural compatibility. However, surprisingly little is known about the electronic properties of the STO/LSAT interface despite its potentially important role in affecting the overall electronic structure of system. We examine the band alignment of STO/LSAT heterostructures using x-ray photoelectron spectroscopy for epitaxial STO films deposited using two different molecular beam epitaxy approaches. We find that the valence band offset ranges from +0.2(1) eV to -0.2(1) eV depending on surface conditions for the film and substrate. From these results we extract a conduction band offset from -2.4(1) eV to -2.8(1) eV, indicating that the conduction band edge is more deeply bound in STO and that LSAT will not act as a sink or trap for electrons in the supported film or multilayer.

  11. Study of the microstructure of plasma sprayed coatings obtained from Al{sub 2}O{sub 3}13TiO{sub 2} nanostructured and conventional powders

    SciTech Connect (OSTI)

    Gral, A.; ?rawski, W.; Lity?ska-Dobrzy?ska, L.

    2014-10-15

    The microstructure of coatings obtained from nanostructured or conventional Al{sub 2}O{sub 3}13TiO{sub 2} powders and deposited by plasma spraying technique on low-carbon steel was examined by transmission electron microscopy techniques. The dominating phase in both coatings was ?-Al{sub 2}O{sub 3} phase. It has been observed that the grains of ?-Al{sub 2}O{sub 3} grew in various shapes and sizes, that are particularly visible in the case of coating sprayed from nanostructured powder. The coatings obtained from the fully melted conventional powders exhibited a typical lamellar microstructure, into which the strips of TiO{sub 2} phase were extended. The microstructure of coatings produced from agglomerates of nanostructured particles also revealed the regions consisting of partially melted ?-Al{sub 2}O{sub 3} powders surrounded by the net-like structure formed from fully melted oxides that improved the coating properties. Along with the observed morphology diversity some changes in the chemical composition on the cross sections of obtained coatings have been also noticed. - Highlights: Plasma sprayed Al{sub 2}O{sub 3}13TiO{sub 2} coatings reveal diversity of microstructure. Microstructure of conventional coating was formed from fully melted crushed powders. Nanostructured coating contains completely and partially melted initial agglomerates.

  12. Complex-compound low-temperature TES system

    SciTech Connect (OSTI)

    Rockenfeller, U.

    1989-03-01

    Development of a complex-compound low-temperature TES system is described herein from basic chemical principles through current bench scale system development. Important application engineering issues and an economic outlook are addressed as well. The system described uses adsorption reactions between solid metal inorganic salts and ammonia refrigerant. It is the coordinative nature of these reactions that allows for storage of ammonia refrigerant within the solid salt crystals that function as a chemical compressor during on peak periods (substituting the mechanical compressor) and release ammonia during off peak periods while a mechanical vapor compression system provides the necessary reactor pressure and heat.

  13. Structural and magnetic properties of Co{sub 2}Ti{sub 1−x}Fe{sub x}Al (0 ≤ x ≤ 0.5) alloys

    SciTech Connect (OSTI)

    Pal, Lakhan Gupta, Sachin Suresh, K. G.

    2014-04-24

    In this work we studied the effect of partial Fe substitution for Ti on the structural and magnetic properties of the Co{sub 2}TiAl. X-ray diffraction analysis indicates the presence of B2 type disorder for x > 0, (111) reflections are absent for x > 0 which is the characteristic of B2 type disorder. XRD analysis also shows presence of second phase. Magnetization measurements also confirm the presence of dual phase. Curie temperature of the alloys increases with increase in Fe concentration. Saturation magnetic moments agree very well with those calculated by Slater-Pauling rule.

  14. Effects of the microstructure and porosity on properties of Ti-6Al-4V ELI alloy fabricated by electron beam melting (EBM)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Galarraga, Haize; Lados, Diana A.; Dehoff, Ryan R.; Kirka, Michael M.; Nandwana, Peeyush

    2016-01-01

    Electron Beam Melting (EBM) is a metal powder bed-based Additive Manufacturing (AM) technology that makes possible the fabrication of three dimensional near-net-shaped parts directly from computer models. EBM technology has been in continuously updating, obtaining optimized properties of the processed alloys. Ti-6Al-4V titanium alloy is the most widely used and studied alloy for this technology and is the focus of this work. Several research works have been completed to study the mechanisms of microstructure formation as well as its influence on mechanical properties. However, the relationship is not completely understood, and more systematic research work is necessary in order tomore » attain a better understanding of these features. In this work, samples fabricated at different locations, orientations, and distances from the build platform have been characterized, studying the relationship of these variables with the resulting material intrinsic characteristics and properties (surface topography, microstructure, porosity, micro-hardness and static mechanical properties). This study has revealed that porosity is the main factor controlling mechanical properties relative to the other studied variables. Therefore, in future process developments, decreasing of the porosity should be considered as the primary goal in order to improve mechanical properties.« less

  15. Growth-induced electron mobility enhancement at the LaAlO{sub 3}/SrTiO{sub 3} interface

    SciTech Connect (OSTI)

    Fête, A.; Cancellieri, C.; Li, D.; Stornaiuolo, D.; Caviglia, A. D.; Gariglio, S.; Triscone, J.-M.

    2015-02-02

    We have studied the electronic properties of the 2D electron liquid present at the LaAlO{sub 3}/SrTiO{sub 3} interface in series of samples prepared at different growth temperatures. We observe that interfaces fabricated at 650 °C exhibit the highest low temperature mobility (≈10 000 cm{sup 2} V{sup −1} s{sup −1}) and the lowest sheet carrier density (≈5×10{sup 12} cm{sup −2}). These samples show metallic behavior and Shubnikov-de Haas oscillations in their magnetoresistance. Samples grown at higher temperatures (800–900 °C) display carrier densities in the range of ≈2−5×10{sup 13} cm{sup −2} and mobilities of ≈1000 cm{sup 2} V{sup −1} s{sup −1} at 4 K. Reducing their carrier density by field effect to 8×10{sup 12} cm{sup −2} lowers their mobilities to ≈50 cm{sup 2} V{sup −1} s{sup −1} bringing the conductance to the weak-localization regime.

  16. Effects of the microstructure and porosity on properties of Ti-6Al-4V ELI alloy fabricated by electron beam melting (EBM)

    SciTech Connect (OSTI)

    Galarraga, Haize; Lados, Diana A.; Dehoff, Ryan R.; Kirka, Michael M.; Nandwana, Peeyush

    2016-01-01

    Electron Beam Melting (EBM) is a metal powder bed-based Additive Manufacturing (AM) technology that makes possible the fabrication of three dimensional near-net-shaped parts directly from computer models. EBM technology has been in continuously updating, obtaining optimized properties of the processed alloys. Ti-6Al-4V titanium alloy is the most widely used and studied alloy for this technology and is the focus of this work. Several research works have been completed to study the mechanisms of microstructure formation as well as its influence on mechanical properties. However, the relationship is not completely understood, and more systematic research work is necessary in order to attain a better understanding of these features. In this work, samples fabricated at different locations, orientations, and distances from the build platform have been characterized, studying the relationship of these variables with the resulting material intrinsic characteristics and properties (surface topography, microstructure, porosity, micro-hardness and static mechanical properties). This study has revealed that porosity is the main factor controlling mechanical properties relative to the other studied variables. Therefore, in future process developments, decreasing of the porosity should be considered as the primary goal in order to improve mechanical properties.

  17. Effects of the microstructure and porosity on properties of Ti-6Al-4V alloy fabricated by Electron Beam Melting (EBM)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Galarraga, Haize; Lados, Diana; Dehoff, Ryan R; Kirka, Michael M; Nandwana, Peeyush

    2016-01-01

    Electron Beam Melting (EBM) is a metal powder bed-based Additive Manufacturing (AM) technology that makes possible the fabrication of three dimensional near-net-shaped parts directly from computer models. EBM technology has been in continuously updating, obtaining optimized properties of the processed alloys. Ti-6Al-4V titanium alloy is the most widely used and studied alloy for this technology and is the focus of this work. Several research works have been completed to study the mechanisms of microstructure formation as well as its influence on mechanical properties. However, the relationship is not completely understood, and more systematic research work is necessary in order tomoreattain a better understanding of these features. In this work, samples fabricated at different locations, orientations, and distances from the build platform have been characterized, studying the relationship of these variables with the resulting material intrinsic characteristics and properties (surface topography, microstructure, porosity, micro-hardness and static mechanical properties). This study has revealed that porosity is the main factor controlling mechanical properties relative to the other studied variables. Therefore, in future process developments, decreasing of the porosity should be considered as the primary goal in order to improve mechanical properties.less

  18. Polar asymmetry of La{sub (1−δ)}Al{sub (1+δ)}O{sub 3}/SrTiO{sub 3} heterostructures probed by optical second harmonic generation

    SciTech Connect (OSTI)

    Rubano, Andrea; De Luca, Gabriele; Marrucci, Lorenzo; Paparo, Domenico; Schubert, Jürgen; Wang, Zhe; Zhu, Shaobo; Schlom, Darrell G.

    2015-09-07

    By combining transport measurements and optical second harmonic generation, we have investigated heterostructures formed between crystalline thin films of LaAlO{sub 3}, with varying stoichiometry and TiO{sub 2}-terminated SrTiO{sub 3}(001) substrates. Optical second harmonic generation directly probes the polarity of these heterostructures, thus complementing the transport data. The stoichiometry and the growth temperature are found to be critical parameters for controlling both the interfacial conductivity and the heterostructure polarity. In agreement with the previous work, all of the samples display an insulator-to-metal transition in the Al-reach region, with the conductivity first increasing and then saturating at the highest Al/La ratios. The second harmonic signal also increases as a function of the Al/La ratio, but, at the highest growth temperature, it does not saturate. This unusual behavior is consistent with the formation of an ordered structure of defect dipoles in the LaAlO{sub 3} film caused by the off-centering of excess Al atoms in agreement with the theory.

  19. Case studies of thermal energy storage (TES) systems: Evaluation and verification of system performance

    SciTech Connect (OSTI)

    Akbari, H.; Sezgen, O.

    1992-01-01

    We have developed two case studies to review and analyze energy performance of thermal energy storage CMS systems in commercial buildings. Our case studies considered two partial ice storage systems in Northern California. For each case, we compiled historical data on TES design, installation, and operation. This information was further enhanced by data obtained through interviews with the building owners and operators. The performance and historical data of the TES systems and their components were grouped into issues related to design, installation, operation, and maintenance of the systems. Our analysis indicated that (1) almost all problems related to the operation of TES and non-TES systems could be traced back to the design of the system, and (2) the identified problems were not unique to the TES systems. There were as many original problems with conventional'' HVAC systems and components as with TES systems. Judging from the problems related to non-TES components identified in these two case studies, it is reasonable to conclude that conventional systems have as many problems as TES systems, but a failure, in a TES system may have a more dramatic impact on thermal comfort and electricity charges. The objective of the designers of the TES systems in the case-study buildings was to design just-the-right-size systems so that both the initial investment and operating costs would be minimized. Given such criteria, a system is typically designed only for normal and steady-state operating conditions-which often precludes due consideration to factors such as maintenance, growth in the needed capacity, ease of the operation, and modularity of the systems. Therefore, it is not surprising to find that these systems, at least initially, did not perform to the design intent and expectation and that they had to go through extended periods of trouble-shooting.

  20. Case studies of thermal energy storage (TES) systems: Evaluation and verification of system performance. Final report

    SciTech Connect (OSTI)

    Akbari, H.; Sezgen, O.

    1992-01-01

    We have developed two case studies to review and analyze energy performance of thermal energy storage CMS systems in commercial buildings. Our case studies considered two partial ice storage systems in Northern California. For each case, we compiled historical data on TES design, installation, and operation. This information was further enhanced by data obtained through interviews with the building owners and operators. The performance and historical data of the TES systems and their components were grouped into issues related to design, installation, operation, and maintenance of the systems. Our analysis indicated that (1) almost all problems related to the operation of TES and non-TES systems could be traced back to the design of the system, and (2) the identified problems were not unique to the TES systems. There were as many original problems with ``conventional`` HVAC systems and components as with TES systems. Judging from the problems related to non-TES components identified in these two case studies, it is reasonable to conclude that conventional systems have as many problems as TES systems, but a failure, in a TES system may have a more dramatic impact on thermal comfort and electricity charges. The objective of the designers of the TES systems in the case-study buildings was to design just-the-right-size systems so that both the initial investment and operating costs would be minimized. Given such criteria, a system is typically designed only for normal and steady-state operating conditions-which often precludes due consideration to factors such as maintenance, growth in the needed capacity, ease of the operation, and modularity of the systems. Therefore, it is not surprising to find that these systems, at least initially, did not perform to the design intent and expectation and that they had to go through extended periods of trouble-shooting.

  1. Enhancing the stability of copper chromite catalysts for the selective hydrogenation of furfural with ALD overcoating (II) – Comparison between TiO2 and Al2O3 overcoatings

    SciTech Connect (OSTI)

    Zhang, Hongbo; Canlas, Christian; Kropf, A. Jeremy; Elam, Jeffrey W.; Dumesic, James A; Marshall, Christopher L.

    2015-01-01

    TiO2 atomic layer deposition (ALD) overcoatings were applied to copper chromite catalysts to increase the stability for 2-furfuraldehyde (“furfural”) hydrogenation. After overcoating, about 75% activity was preserved compared to neat copper chromite: much higher activity than an alumina ALD overcoated catalyst with a similar number of ALD cycles. The effects of ALD TiO2 on the active Cu nanoparticles were studied extensively using both in-situ TPR/isothermal-oxidation and in-situ furfural hydrogenation via Cu XAFS. The redox properties of Cu were modified only slightly by the TiO2 ALD overcoat. However, a subtle electronic interaction was observed between the TiO2 ALD layers and the Cu nanoparticles. With calcination at 500 °C the interaction between the TiO2 overcoat and the underlying catalyst is strong enough to inhibit migration and site blocking by chromite, but is sufficiently weaker than the interaction between the Al2O3 overcoat and copper chromite that it does not strongly inhibit the catalytic activity of the copper nanoparticles.

  2. On the effect of deep-rolling and laser-peening on the stress-controlled low- and high-cycle fatigue behavior of Ti-6Al-4V at elevated temperatures up to 550?C

    SciTech Connect (OSTI)

    Ritchie, IAltenberger, RKNalla, YSano LWagner, RO

    2012-04-01

    The effect of surface treatment on the stress/life fatigue behavior of a titanium Ti-6Al-4V turbine fan blade alloy is investigated in the regime of 102 to 106 cycles to failure under fully reversed stress-controlled isothermal push-pull loading between 25? and 550?C at a frequency of 5 Hz. Specifically, the fatigue behavior was examined in specimens in the deep-rolled and laser-shock peened surface conditions, and compared to results on samples in the untreated (machined and stress annealed) condition. Although the fatigue resistance of the Ti-6Al-4V alloy declined with increasing test temperature regardless of surface condition, deep-rolling and laser-shock peening surface treatments were found to extend the fatigue lives by factors of more than 30 and 5-10, respectively, in the high-cycle and low-cycle fatigue regimes at temperatures as high as 550?C. At these temperatures, compressive residual stresses are essentially relaxed; however, it is the presence of near-surface work hardened layers, with a nanocystalline structure in the case of deep-rolling and dense dislocation tangles in the case of laser-shock peening, which remain fairly stable even after cycling at 450?-550?C, that provide the basis for the beneficial role of mechanical surface treatments on the fatigue strength of Ti-6Al-4V at elevated temperatures.

  3. Nanostructured aluminium titanate (Al{sub 2}TiO{sub 5}) particles and nanofibers: Synthesis and mechanism of microstructural evolution

    SciTech Connect (OSTI)

    Azarniya, Abolfazl; Azarniya, Amir; Hosseini, Hamid Reza Madaah; Simchi, Abdolreza

    2015-05-15

    In this study, aluminium titanate (AT) particles and nanofibers were synthesized through citrate sol gel and sol gel-assisted electrospinning methods in both nanostructured powder and nanofiber forms. The results of X-ray diffraction analysis, field-emission scanning electron microscopy and differential thermal analysis showed that the synthetic products benefit a nanostructured nature with a grain size less than 70 nm. The optimal values for time and temperature at which a roughly pure AT is attained were determined as 2 h and 900 °C, respectively. It was found that the sol gel precursor bears an amorphous structure till 700 °C and begins to be crystallized to alumina, anatase and AT at higher temperatures. Moreover, AT tends to decompose into rutile and alumina at temperatures higher than 900 °C and its degradation rate reaches a maximum at temperatures near to 1100 °C. In this synthesis, citric acid was used as a chelating agent for Al{sup 3} {sup +} and Ti{sup 4} {sup +} ions and it was shown that a low citric acid-to-metal cation ratio leads to larger numbers of nuclei during crystallization and smaller grain size. Finally, a model was suggested to describe the microstructural evolution of AT compound based on a nucleation and growth regime. - Graphical abstract: Display Omitted - Highlights: • We synthesized aluminium titanate ceramic in both powder and nanofiber forms. • The methods in use were citrate sol gel and sol gel-assisted electrospinning. • Powders and nanofibers bear a nanostructured nature with a grain size less than 70 nm. • A model is suggested to describe microstructural evolution of synthetic products.

  4. The Effects of Oxide Supports on the Low Temperature Hydrogenation Activity of Acetone over Pt/Ni Bimetallic Catalysts on SiO2 gamma-Al2O3 and TiO2

    SciTech Connect (OSTI)

    S Qi; B Cheney; R Zheng; W Lonergan; W Yu; J Chen

    2011-12-31

    Low temperature (308 K) hydrogenation of acetone was used as a probe reaction to investigate the support effect on the hydrogenation activity of Pt/Ni bimetallic catalysts supported on TiO{sub 2}, SiO{sub 2} and {gamma}-Al{sub 2}O{sub 3}. The oxide supports significantly affected the catalytic properties of Pt/Ni catalysts, in which Pt/Ni/SiO2 bimetallic catalysts exhibited significantly higher activity than the other two bimetallic catalysts. TEM measurements revealed that the three supported Pt/Ni bimetallic catalysts have similar particle size distribution, while CO chemisorption measurements showed very different chemisorption capacity. Extended X-Ray absorption fine structure (EXAFS) measurements of the Pt L{sub III}-edge indicated that Pt atoms were fully reduced and the Pt-Ni bimetallic bonds were formed on all three catalysts. The extent of Pt-Ni bond formation followed the trend of SiO{sub 2} > {gamma}-Al{sub 2}O{sub 3} > TiO{sub 2}, which correlated very well with the hydrogenation activity.

  5. Phase Relations and Elemental Distribution Among Co-Existing Phases in the Ceramics of the Pseudobinary System CaZrTi{sub 2}O{sub 7}-LnAlO{sub 3} (Ln= Nd, Sm)

    SciTech Connect (OSTI)

    Mikhailenko, Natalia; Stefanovsky, Sergey

    2007-07-01

    In the ceramics in series (1-x) CaZrTi{sub 2}O{sub 7} - x NdAlO{sub 3} and (1-x) CaZrTi{sub 2}O{sub 7} - x SmAlO{sub 3} (x = 0.25, 0.5 and 0.75) produced by cold pressing and sintering at 1400, 1450 and 1500 deg. C zirconolite was found to be a major phase, perovskite was an extra phase and traces of residual baddeleyite occurred. At x = 0.75 the perovskite was major phase and zirconolite and cubic oxide of fianite or tazheranite type were extra phases. Major Nd and Sm host phase at x = 0.25 was found to be zirconolite (about 65% of total Nd{sub 2}O{sub 3} and 74% of total Sm{sub 2}O{sub 3}). With the x value increasing perovskite becomes major host phase for Nd and Sm accumulating of up to about 92% of total Nd and about 72% of total Sm. As follows from SEM/EDS data Nd and Sm contents in the zirconolite may reach {approx}1 formula unit (fu). (authors)

  6. Integrating CSP w/ TES into a Utility System | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Integrating CSP w/ TES into a Utility System Integrating CSP w/ TES into a Utility System This presentation was delivered at the SunShot Concentrating Solar Power (CSP) Program Review 2013, held April 23-25, 2013 near Phoenix, Arizona. csp_review_meeting_042513_albert.pdf (1.81 MB) More Documents & Publications EA-1683: Final Environmental Assessment SunShot Vision Study: February 2012 (Book), SunShot, Energy Efficiency & Renewable Energy (EERE) A New Generation of Parabolic Trough

  7. Comparison of improved Aura Tropospheric Emission Spectrometer (TES) CO{sub 2} with HIPPO and SGP aircraft profile measurements

    SciTech Connect (OSTI)

    Kulawik, S. S.; Worden, J. R.; Wofsy, S. C.; Biraud, S. C.; Nassar, R.; Jones, D. B.A.; Olsen, E. T.; Osterman, G. B.

    2012-02-01

    Comparisons are made between mid-tropospheric Tropospheric Emission Spectrometer (TES) carbon dioxide (CO{sub 2}) satellite measurements and ocean profiles from three Hiaper Pole-to-Pole Observations (HIPPO) campaigns and land aircraft profiles from the United States Southern Great Plains (SGP) Atmospheric Radiation Measurement (ARM) site over a 4-yr period. These comparisons are used to characterize the bias in the TES CO{sub 2} estimates and to assess whether calculated and actual uncertainties and sensitivities are consistent. The HIPPO dataset is one of the few datasets spanning the altitude range where TES CO{sub 2} estimates are sensitive, which is especially important for characterization of biases. We find that TES CO{sub 2} estimates capture the seasonal and latitudinal gradients observed by HIPPO CO{sub 2} measurements; actual errors range from 0.8–1.2 ppm, depending on the campaign, and are approximately 1.4 times larger than the predicted errors. The bias of TES versus HIPPO is within 0.85 ppm for each of the 3 campaigns; however several of the sub-tropical TES CO{sub 2} estimates are lower than expected based on the calculated errors. Comparisons of aircraft flask profiles, which are measured from the surface to 5 km, to TES CO{sub 2} at the SGP ARM site show good agreement with an overall bias of 0.1 ppm and rms of 1.0 ppm. We also find that the predicted sensitivity of the TES CO{sub 2} estimates is too high, which results from using a multi-step retrieval for CO{sub 2} and temperature. We find that the averaging kernel in the TES product corrected by a pressure-dependent factor accurately reflects the sensitivity of the TES CO{sub 2} product.

  8. External review of the thermal energy storage (TES) cogeneration study assumptions. Final report

    SciTech Connect (OSTI)

    Lai, B.Y.; Poirier, R.N.

    1996-08-01

    This report is to provide a detailed review of the basic assumptions made in the design, sizing, performance, and economic models used in the thermal energy storage (TES)/cogeneration feasibility studies conducted by Pacific Northwest Laboratory (PNL) staff. This report is the deliverable required under the contract.

  9. Structure and Electrochemistry of LiNi1/3Co1/3-yMyMn1/3O2 (M=Ti, Al, Fe) Positive Electrode Materials

    SciTech Connect (OSTI)

    Wilcox, James; Patoux, Sebastien; Doeff, Marca

    2009-01-14

    A series of materials based on the LiNi1/3Co1/3-yMyMn1/3O2 (M = Ti,Al,Fe) system has been synthesized and examined structurally and electrochemically. It is found that the changes in electrochemical performance depend highly on the nature of the substituting atom and its effect on the crystal structure. Substitution with small amounts of Ti4+ (y = 1/12) leads to the formation of a high-capacity and high-rate positive electrode material. Iron substituted materials suffer from an increased antisite defect concentration and exhibit lower capacities and poor rate capabilities. Single-phase materials are found for LiNi1/3Co1/3-yAlyMn1/3O2 when y<_ 1/4 and all exhibit decreased capacities when cycled to 4.3 V. However, an increase in rate performance and cycle stability upon aluminum substitution is correlated with an improved lamellar structure.

  10. Microstructure and dielectric properties of Ba{sub 1-x}Sr{sub x}TiO{sub 3} films grown on LaAlO{sub 3} substrates

    SciTech Connect (OSTI)

    Gim, Y.; Hudson, T.; Fan, Y.; Kwon, C.; Findikoglu, A. T.; Gibbons, B. J.; Park, B. H.; Jia, Q. X.

    2000-08-21

    We report a systematic study of the microstructure and dielectric properties of barium strontium titanate, Ba{sub 1-x}Sr{sub x}TiO{sub 3}, films grown by laser ablation on LaAlO{sub 3} substrates, where x=0.1-0.9 at an interval of 0.1. X-ray diffraction analysis shows that when x<0.4, the longest unit-cell axis is parallel to the plane of the substrate but perpendicular as x approaches 1. Dielectric constant versus temperature measurements show that the relative dielectric constant has a maximum value and that the peak temperatures corresponding to the maximum relative dielectric constant are about 70 degree sign C higher when x{<=}0.4 but similar when x>0.4, compared with the peak temperatures of the bulk Ba{sub 1-x}Sr{sub x}TiO{sub 3}. At room temperature, the dielectric constant and tunability are relatively high when x{<=}0.4 but start to decrease rapidly as x increases. (c) 2000 American Institute of Physics.

  11. Friction behavior of a multi-interface system and improved performance by AlMgB14–TiB2–C and diamond-like-carbon coatings

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Qu, Jun; Blau, Peter J.; Higdon, Clifton; Cook, Bruce A.

    2016-03-29

    We investigated friction behavior of a bearing system with two interfaces involved: a roller component experiencing rolling–sliding interaction against twin cylinders under point contacts while simultaneously undergoing pure sliding interaction against a socket under a conformal contact. Lubrication modeling predicted a strong correlation between the roller's rolling condition and the system's friction behavior. Experimental observations first validated the analytical predictions using steel and iron components. Diamond-like-carbon (DLC) coating and AlMgB14–TiB2 coating with a carbon topcoat (BAMC) were then applied to the roller and twin cylinders, respectively. In conclusion, testing and analysis results suggest that the coatings effectively decreased the slipmore » ratio for the roller–cylinder contact and the sliding friction at both bearing interfaces and, as a result, significantly reduced the system frictional torque.« less

  12. High-Temperature Phase Change Materials (PCM) Candidates for Thermal Energy Storage (TES) Applications

    SciTech Connect (OSTI)

    Gomez, J. C.

    2011-09-01

    It is clearly understood that lower overall costs are a key factor to make renewable energy technologies competitive with traditional energy sources. Energy storage technology is one path to increase the value and reduce the cost of all renewable energy supplies. Concentrating solar power (CSP) technologies have the ability to dispatch electrical output to match peak demand periods by employing thermal energy storage (TES). Energy storage technologies require efficient materials with high energy density. Latent heat TES systems using phase change material (PCM) are useful because of their ability to charge and discharge a large amount of heat from a small mass at constant temperature during a phase transformation like melting-solidification. PCM technology relies on the energy absorption/liberation of the latent heat during a physical transformation. The main objective of this report is to provide an assessment of molten salts and metallic alloys proposed as candidate PCMs for TES applications, particularly in solar parabolic trough electrical power plants at a temperature range from 300..deg..C to 500..deg.. C. The physical properties most relevant for PCMs service were reviewed from the candidate selection list. Some of the PCM candidates were characterized for: chemical stability with some container materials; phase change transformation temperatures; and latent heats.

  13. High performance TiN gate contact on AlGaN/GaN transistor using a mechanically strain induced P-doping

    SciTech Connect (OSTI)

    Soltani, A. Rousseau, M.; Gerbedoen, J.-C.; Bourzgui, N.; Mattalah, M.; Bonanno, P. L.; Ougazzaden, A.; Telia, A.; Patriarche, G.; BenMoussa, A.

    2014-06-09

    High performance titanium nitride sub-100 nm rectifying contact, deposited by sputtering on AlGaN/GaN high electron mobility transistors, shows a reverse leakage current as low as 38 pA/mm at V{sub GS} = −40 V and a Schottky barrier height of 0.95 eV. Based on structural characterization and 3D simulations, it is found that the polarization gradient induced by the gate metallization forms a P-type pseudo-doping region under the gate between the tensile surface and the compressively strained bulk AlGaN barrier layer. The strain induced by the gate metallization can compensate for the piezoelectric component. As a result, the gate contact can operate at temperatures as high as 700 °C and can withstand a large reverse bias of up to −100 V, which is interesting for high-performance transistors dedicated to power applications.

  14. Conductance control at the LaAlO{sub 3}/SrTiO{sub 3}-interface by a multiferroic BiFeO{sub 3} ad-layer

    SciTech Connect (OSTI)

    Mix, Christian; Finizio, Simone; Kläui, Mathias; Jakob, Gerhard

    2014-06-30

    Multilayered BiFeO{sub 3} (BFO)/LaAlO{sub 3} (LAO) thin film samples were fabricated on SrTiO{sub 3} (STO) substrates by pulsed laser deposition. In this work, the ferroelectric polarization of a multiferroic BFO ad-layer on top of the quasi-two-dimensional electron gas (2DEG) at the LAO/STO interface is used to manipulate the conductivity of the quasi-2DEG. By microstructuring the conductive area of the LAO/STO-interface, a four-point geometry for the measurement of the resistivity was achieved. Piezo force microscopy allows for imaging and poling the spontaneous ferroelectric polarization of the multiferroic layer. The resistance changes showed a linear dependence on the area scanned and a hysteretic behavior with respect to the voltages applied in the scanning process. This is evidence for the ferroelectric polarization of the multiferroic causing the resistance changes. Coupling the antiferromagnetic BFO layer to another ferromagnetic layer could enable a magnetic field control of the conductance of the quasi-2DEG at the LAO/STO interface.

  15. A chemical confirmation of the faint Boötes II dwarf spheroidal galaxy

    SciTech Connect (OSTI)

    Koch, Andreas; Rich, R. Michael

    2014-10-10

    We present a chemical abundance study of the brightest confirmed member star of the ultra-faint dwarf galaxy Boötes II from Keck/HIRES high-resolution spectroscopy at moderate signal-to-noise ratios. At [Fe/H] = –2.93 ± 0.03(stat.) ± 0.17(sys.), this star chemically resembles metal-poor halo field stars and the signatures of other faint dwarf spheroidal galaxies at the same metallicities in that it shows enhanced [α/Fe] ratios, Solar Fe-peak element abundances, and low upper limits on the neutron-capture element Ba. Moreover, this star shows no chemical peculiarities in any of the eight elements we were able to measure. This implies that the chemical outliers found in other systems remain outliers pertaining to the unusual enrichment histories of the respective environments, while Boo II appears to have experienced an enrichment history typical of its very low mass. We also re-calibrated previous measurements of the galaxy's metallicity from the calcium triplet (CaT) and find a much lower value than reported before. The resulting broad metallicity spread, in excess of one dex, the very metal-poor mean, and the chemical abundance patterns of the present star imply that Boötes II is a low-mass, old, metal-poor dwarf galaxy and not an overdensity associated with the Sagittarius Stream as has been previously suggested based on its sky position and kinematics. The low, mean CaT metallicity of –2.7 dex falls right on the luminosity-metallicity relation delineated over four orders of magnitude from the more luminous to the faintest galaxies. Thus Boötes II's chemical enrichment appears representative of the galaxy's original mass, while tidal stripping and other mass loss mechanisms were probably not significant as for other low-mass satellites.

  16. Exploration of R2XM2 (R=Sc, Y, Ti, Zr, Hf, rare earth; X=main group element; M=transition metal, Si, Ge): Structural Motifs, the novel Compound Gd2AlGe2 and Analysis of the U3Si2 and Zr3Al2 Structure Types

    SciTech Connect (OSTI)

    Sean William McWhorter

    2006-05-01

    In the process of exploring and understanding the influence of crystal structure on the system of compounds with the composition Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} several new compounds were synthesized with different crystal structures, but similar structural features. In Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4}, the main feature of interest is the magnetocaloric effect (MCE), which allows the material to be useful in magnetic refrigeration applications. The MCE is based on the magnetic interactions of the Gd atoms in the crystal structure, which varies with x (the amount of Si in the compound). The crystal structure of Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} can be thought of as being formed from two 3{sup 2}434 nets of Gd atoms, with additional Gd atoms in the cubic voids and Si/Ge atoms in the trigonal prismatic voids. Attempts were made to substitute nonmagnetic atoms for magnetic Gd using In, Mg and Al. Gd{sub 2}MgGe{sub 2} and Gd{sub 2}InGe{sub 2} both possess the same 3{sup 2}434 nets of Gd atoms as Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4}, but these nets are connected differently, forming the Mo{sub 2}FeB{sub 2} crystal structure. A search of the literature revealed that compounds with the composition R{sub 2}XM{sub 2} (R=Sc, Y, Ti, Zr, Hf, rare earth; X=main group element; M=transition metal, Si, Ge) crystallize in one of four crystal structures: the Mo{sub 2}FeB{sub 2}, Zr{sub 3}Al{sub 2}, Mn{sub 2}AlB{sub 2} and W{sub 2}CoB{sub 2} crystal structures. These crystal structures are described, and the relationships between them are highlighted. Gd{sub 2}AlGe{sub 2} forms an entirely new crystal structure, and the details of its synthesis and characterization are given. Electronic structure calculations are performed to understand the nature of bonding in this compound and how electrons can be accounted for. A series of electronic structure calculations were performed on models with the U{sub 3}Si{sub 2} and Zr{sub 3}Al{sub 2} structures, using Zr and A1 as

  17. Elastic anisotropy, vibrational, and thermodynamic properties of U{sub 2}Ti intermetallic compound with AlB{sub 2}-type structure under high pressure up to 100 GPa

    SciTech Connect (OSTI)

    Yang, Jinwen; Gao, Tao; Liu, Benqiong; Sun, Guangai; Chen, Bo

    2015-03-28

    Structural, elastic anisotropy, dynamical, and thermodynamic properties of U{sub 2}Ti have been studied by employing density functional theory and density functional perturbative theory. The optimized lattice parameters a, c, unit volume V, bulk modulus B, and bond lengths d{sub U-U}, d{sub U-Ti} of U{sub 2}Ti are in favorable agreement with the available experimental data and other theoretical values. The elastic constants under pressure were obtained using “energy-strain” method. The polycrystalline modulus, Poisson's ratio, brittle/ductile characteristics, Debye temperature and the integration of elastic wave velocities over different directions, and hardness under pressure are also evaluated successfully. The anisotropy of the directional bulk modulus and the Young's modulus is systematically predicted for the first time. It turns out that U{sub 2}Ti should be stabilized mechanically up to 100 GPa, this compound just possesses slightly elastic anisotropy at zero pressure; however, the anisotropy becomes more and more significant with the increasing pressure. In particular, the phonon dispersion curves and phonon density of state under pressure are reported for the first time. The Raman and infrared-active phonon modes at Γ point are further assigned. Our results indicate that U{sub 2}Ti is also stable dynamically up to 100 GPa. Additionally, within the calculated phonon density of states, the thermodynamic properties are predicted.

  18. Dielectric properties of <001>-oriented Ba{sub 0.6}Sr{sub 0.4}TiO{sub 3} thin films on polycrystalline metal tapes using biaxially oriented MgO/{gamma}-Al{sub 2}O{sub 3} buffer layers

    SciTech Connect (OSTI)

    Choi, W.; Kang, B.S.; Jia, Q.X.; Matias, V.; Findikoglu, A.T.

    2006-02-06

    We report the growth of <001>-oriented Ba{sub 0.6}Sr{sub 0.4}TiO{sub 3} (BST) thin films on polycrystalline Ni-alloy tapes by pulsed laser deposition using biaxially oriented, ion-beam-assisted deposited (IBAD) MgO and {gamma}-Al{sub 2}O{sub 3} buffer layers. Dielectric constant values of our BST films were up to {approx}85% of those in the epitaxial films prepared under similar conditions on single-crystal MgO substrates. No significant dispersion of the dielectric constant was observed for frequencies from 100 Hz to 1 MHz. These results demonstrate the versatility of using IBAD-textured MgO and {gamma}-Al{sub 2}O{sub 3} buffer layers to integrate highly oriented good-quality BST films with nonsingle-crystalline substrates.

  19. ALS Spectrum

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Spectrum Print Begun in 2007, ALS Spectrum is a publication that encapsulates the same type of information contained in the ALS Activity Report but in a short, readable, ...

  20. ALS@20

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    tribulations encountered during the construction of the ALS from former Director Jay Marx, current ALS Scientific Director Steve Kevan and Director Roger Falcone talked about...

  1. ALS Spectrum

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Spectrum Print Begun in 2007, ALS Spectrum is a publication that encapsulates the same type of information contained in the ALS Activity Report but in a short, readable,...

  2. Industry @ ALS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Industry @ ALS Industry @ ALS Hewlett Packard Labs Gains Insights with Innovative ALS Research Tools Print Thursday, 05 May 2016 11:21 For the past eight years, Hewlett Packard Labs, the central research organization of Hewlett Packard Enterprise, has been using cutting-edge ALS techniques to advance some of their most promising technological research, including vanadium dioxide phase transitions and atomic movement during memristor operation. Summary Slide Read more... ALS, Molecular Foundry,

  3. ALS Spectrum

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Spectrum Print Begun in 2007, ALS Spectrum is a publication that encapsulates the same type of information contained in the ALS Activity Report but in a short, readable, newsletter-like format. Featured scientific and facility developments are front-paged, and a roundup of science highlights is provided in easily browsable summaries with Web links. Contents also include brief reports from ALS staff and user groups, articles about ALS people and events, and facility updates. These documents

  4. ALS Spectrum

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Spectrum Print Begun in 2007, ALS Spectrum is a publication that encapsulates the same type of information contained in the ALS Activity Report but in a short, readable, newsletter-like format. Featured scientific and facility developments are front-paged, and a roundup of science highlights is provided in easily browsable summaries with Web links. Contents also include brief reports from ALS staff and user groups, articles about ALS people and events, and facility updates. These documents

  5. X-ray-selected galaxy groups in Boötes

    SciTech Connect (OSTI)

    Vajgel, Bruna; Lopes, Paulo A. A.; Jones, Christine; Forman, William R.; Murray, Stephen S.; Goulding, Andrew; Andrade-Santos, Felipe

    2014-10-10

    We present the X-ray and optical properties of the galaxy groups selected in the Chandra X-Boötes survey. We used follow-up Chandra observations to better define the group sample and their X-ray properties. Group redshifts were measured from the AGN and Galaxy Evolution Survey spectroscopic data. We used photometric data from the NOAO Deep Wide Field Survey to estimate the group richness (N {sub gals}) and the optical luminosity (L {sub opt}). Our final sample comprises 32 systems at z < 1.75 with 14 below z = 0.35. For these 14 systems, we estimate velocity dispersions (σ {sub gr}) and perform a virial analysis to obtain the radii (R {sub 200} and R {sub 500}) and total masses (M {sub 200} and M {sub 500}) for groups with at least 5 galaxy members. We use the Chandra X-ray observations to derive the X-ray luminosity (L{sub X} ). We examine the performance of the group properties σ{sub gr}, L {sub opt}, and L{sub X} , as proxies for the group mass. Understanding how well these observables measure the total mass is important to estimate how precisely the cluster/group mass function is determined. Exploring the scaling relations built with the X-Boötes sample and comparing these with samples from the literature, we find a break in the L{sub X} -M {sub 500} relation at approximately M {sub 500} = 5 × 10{sup 13} M {sub ☉} (for M {sub 500} > 5 × 10{sup 13} M {sub ☉}, M{sub 500}∝L{sub X}{sup 0.61±0.02}, while for M {sub 500} ≤ 5 × 10{sup 13} M {sub ☉}, M{sub 500}∝L{sub X}{sup 0.44±0.05}). Thus, the mass-luminosity relation for galaxy groups cannot be described by the same power law as galaxy clusters. A possible explanation for this break is the dynamical friction, tidal interactions, and projection effects that reduce the velocity dispersion values of the galaxy groups. By extending the cluster luminosity function to the group regime, we predict the number of groups that new X-ray surveys, particularly eROSITA, will detect. Based on our cluster

  6. ALS Spectrum

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Spectrum Print Begun in 2007, ALS Spectrum is a publication that encapsulates the same type of information contained in the ALS Activity Report but in a short, readable, newsletter-like format. Featured scientific and facility developments are front-paged, and a roundup of science highlights is provided in easily browsable summaries with Web links. Contents also include brief reports from ALS staff and user groups, articles about ALS people and events, and facility updates. These documents are

  7. ALS Spectrum

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Spectrum Print Begun in 2007, ALS Spectrum is a publication that encapsulates the same type of information contained in the ALS Activity Report but in a short, readable, newsletter-like format. Featured scientific and facility developments are front-paged, and a roundup of science highlights is provided in easily browsable summaries with Web links. Contents also include brief reports from ALS staff and user groups, articles about ALS people and events, and facility updates. These documents are

  8. Domain matched epitaxial growth of (111) Ba{sub 0.5}Sr{sub 0.5}TiO{sub 3} thin films on (0001) Al{sub 2}O{sub 3} with ZnO buffer layer

    SciTech Connect (OSTI)

    Krishnaprasad, P. S. E-mail: mkj@cusat.ac.in; Jayaraj, M. K. E-mail: mkj@cusat.ac.in; Antony, Aldrin; Rojas, Fredy

    2015-03-28

    Epitaxial (111) Ba{sub 0.5}Sr{sub 0.5}TiO{sub 3} (BST) thin films have been grown by pulsed laser deposition on (0001) Al{sub 2}O{sub 3} substrate with ZnO as buffer layer. The x-ray ?-2?, ?-scan and reciprocal space mapping indicate epitaxial nature of BST thin films. The domain matched epitaxial growth of BST thin films over ZnO buffer layer was confirmed using Fourier filtered high resolution transmission electron microscope images of the film-buffer interface. The incorporation of ZnO buffer layer effectively suppressed the lattice mismatch and promoted domain matched epitaxial growth of BST thin films. Coplanar inter digital capacitors fabricated on epitaxial (111) BST thin films show significantly improved tunable performance over polycrystalline thin films.

  9. Melt Processed Single Phase Hollandite Waste Forms For Nuclear Waste Immobilization: Ba{sub 1.0}Cs{sub 0.3}A{sub 2.3}Ti{sub 5.7}O{sub 16}; A = Cr, Fe, Al

    SciTech Connect (OSTI)

    Brinkman, Kyle; Marra, James; Amoroso, Jake; Conradson, Steven D.; Tang, Ming

    2013-09-23

    Cs is one of the more problematic fission product radionuclides to immobilize due to its high volatility at elevated temperatures, ability to form water soluble compounds, and its mobility in many host materials. The hollandite structure is a promising crystalline host for Cs immobilization and has been traditionally fabricated by solid state sintering methods. This study presents the structure and performance of Ba{sub 1.0}Cs{sub 0.3}A{sub 2.3}Ti{sub 5.7}O{sub 16}; A = Cr, Fe, Al hollandite fabricated by melt processing. Melt processing is considered advantageous given that melters are currently in use for High Level Waste (HLW) vitrification in several countries. This work details the impact of Cr additions that were demonstrated to i) promote the formation of a Cs containing hollandite phase and ii) maintain the stability of the hollandite phase in reducing conditions anticipated for multiphase waste form processing.

  10. Application of Ti-alloys as compressor discs and blades

    SciTech Connect (OSTI)

    Helm, D.

    1999-07-01

    Ti-alloys are widely used as materials for compressor discs, blades, vanes and housings in modern aero-engines due to their excellent strength-to-weight ratio. Their high corrosion resistance and good weldability are additional factors for their application as main compressor components. A variety of different Ti-alloys have been developed in recent years and introduced into jet engines in order to fulfill the large spectrum of required mechanical properties. The main topic of the present paper is to describe the correlation between essential microstructural features of a number of Ti-alloys for compressor disc and blade applications and such mechanical properties as strength, creep and fatigue resistance, fracture toughness, and crack propagation behavior. It will be shown that for different engine requirements the choice of the suitable alloy, as well as tailoring of microstructural features with the aim to achieve an optimized balance of relevant mechanical properties, is necessary. The influence of thermomechanical treatment on morphology and dimensions of phases, and the resulting correlation to mechanical properties, will be discussed in detail for selected Ti-alloys, i.e., Ti-6Al-4V, Ti-6Al-2Sn-4Zr-2Mo and IMI 834 (Ti-5.8Al-4Sn-3.5Zr-0.5Mo-0.7Nb-0.35Si-0.06C). Additionally, effects of surface conditions caused by surface treatment (shot peening) or by service exposure (surface oxidation) will be presented.

  11. Phase equilibria, formation, crystal and electronic structure of ternary compounds in Ti-Ni-Sn and Ti-Ni-Sb ternary systems

    SciTech Connect (OSTI)

    Romaka, V.V.; Rogl, P.; Romaka, L.; Stadnyk, Yu.; Melnychenko, N.; Grytsiv, A.; Falmbigl, M.; Skryabina, N.

    2013-01-15

    The phase equilibria of the Ti-Ni-Sn and Ti-Ni-Sb ternary systems have been studied in the whole concentration range by means of X-ray and EPM analyses at 1073 K and 873 K, respectively. Four ternary intermetallic compounds TiNiSn (MgAgAs-type), TiNi{sub 2-x}Sn (MnCu{sub 2}Al-type), Ti{sub 2}Ni{sub 2}Sn (U{sub 2}Pt{sub 2}Sn-type), and Ti{sub 5}NiSn{sub 3} (Hf{sub 5}CuSn{sub 3}-type) are formed in Ti-Ni-Sn system at 1073 K. The TiNi{sub 2}Sn stannide is characterized by homogeneity in the range of 50-47 at% of Ni. The Ti-Ni-Sb ternary system at 873 K is characterized by formation of three ternary intermetallic compounds, Ti{sub 0.8}NiSb (MgAgAs-type), Ti{sub 5}Ni{sub 0.45}Sb{sub 2.55} (W{sub 5}Si{sub 3}-type), and Ti{sub 5}NiSb{sub 3} (Hf{sub 5}CuSn{sub 3}-type). The solubility of Ni in Ti{sub 0.8}NiSb decreases number of vacancies in Ti site up to Ti{sub 0.91}Ni{sub 1.1}Sb composition. - Graphical abstract: Isothermal section of the Ti-Ni-Sn phase diagram and DOS distribution in hypothetical TiNi{sub 1+x}Sn solid solution. Highlights: Black-Right-Pointing-Pointer Ti-Ni-Sn phase diagram was constructed at 1073 K. Black-Right-Pointing-Pointer Four ternary compounds are formed: TiNiSn, TiNi{sub 2-x}Sn, Ti{sub 2}Ni{sub 2}Sn, and Ti{sub 5}NiSn{sub 3}. Black-Right-Pointing-Pointer Three ternary compounds exist in Ti-Ni-Sb system at 873 K. Black-Right-Pointing-Pointer The TiNi{sub 2}Sb compound is absent.

  12. ALS Visitors

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ... September 2012 Congressman Steve Womack (R-Arkansas) toured the ALS on September 25, along ... Womack, a freshman member of Congress is Vice Chairman of the House Energy and Water ...

  13. Magnetic anisotropy and order structure of L1{sub 0}-FePt(001) single-crystal films grown epitaxially on (001) planes of MgO, SrTiO{sub 3}, and MgAl{sub 2}O{sub 4} substrates

    SciTech Connect (OSTI)

    Hotta, A. Hatayama, M.; Tsumura, K.; Ono, T.; Kikuchi, N.; Okamoto, S.; Kitakami, O.; Shimatsu, T.

    2014-05-07

    L1{sub 0}–FePt(001) single-crystal films were grown epitaxially on SrTiO{sub 3}(001), MgAl{sub 2}O{sub 4}(001), and MgO(001) substrates. Their uniaxial magnetic anisotropy K{sub u} and the order structure were examined for the film thickness t range of 2–14 nm. All series of films show large K{sub u} of 4 × 10{sup 7} erg/cm{sup 3} in the thickness range higher than 10 nm, with order parameter S of 0.8 and saturation magnetization M{sub s} of 1120 emu/cm{sup 3}. K{sub u} decreased gradually as t decreased. The K{sub u} reduction was considerable when t decreased from 4 nm to 2 nm. No marked difference in the thickness dependence of K{sub u} was found in any series of films, although the lattice mismatch between FePt and the substrates was markedly different. K{sub u} reduction showed good agreement with the reduction of S for the films on MgAl{sub 2}O{sub 4} and MgO. The K{sub u} ∼ S{sup 2} plot showed an almost linear relation, which is in good agreement with theoretical predictions. Transmission electron microscopy images for a FePt film on MgO substrate revealed that the lattice mismatch between FePt(001) and MgO(001) was relaxed in the initial 1 or 2 layers of FePt(001) lattices, which is likely to be true also for two other series of films.

  14. ALD Produced B{sub 2}O{sub 3}, Al{sub 2}O{sub 3} and TiO{sub 2} Coatings on Gd{sub 2}O{sub 3} Burnable Poison Nanoparticles and Carbonaceous TRISO Coating Layers

    SciTech Connect (OSTI)

    Weimer, Alan

    2012-11-26

    This project will demonstrate the feasibility of using atomic layer deposition (ALD) to apply ultrathin neutron-absorbing, corrosion-resistant layers consisting of ceramics, metals, or combinations thereof, on particles for enhanced nuclear fuel pellets. Current pellet coating technology utilizes chemical vapor deposition (CVD) in a fluidized bed reactor to deposit thick, porous layers of C (or PyC) and SiC. These graphitic/carbide materials degrade over time owing to fission product bombardment, active oxidation, thermal management issues, and long-term irradiation effects. ALD can be used to deposit potential ceramic barrier materials of interest, including ZrO{sub 2}, Y{sub 2}O{sub 3}:ZrO{sub 2} (YSZ), Al{sub 2}O{sub 3}, and TiO{sub 2}, or neutron-absorbing materials, namely B (in BN or B{sub 2}O{sub 3}) and Gd (in Gd{sub 2}O{sub 3}). This project consists of a two-pronged approach to integrate ALD into the next-generation nuclear plant (NGNP) fuel pellet manufacturing process:

  15. BOO-1137-AN EXTREMELY METAL-POOR STAR IN THE ULTRA-FAINT DWARF SPHEROIDAL GALAXY BOOeTES I

    SciTech Connect (OSTI)

    Norris, John E.; Yong, David; Gilmore, Gerard; Wyse, Rosemary F. G.

    2010-03-01

    We present high-resolution (R {approx} 40,000), high-signal-to-noise ratio (20-90) spectra of an extremely metal-poor giant star Boo-1137 in the 'ultra-faint' dwarf spheroidal galaxy (dSph) Booetes I, absolute magnitude M{sub V} {approx} -6.3. We derive an iron abundance of [Fe/H] = -3.7, making this the most metal-poor star as yet identified in an ultra-faint dSph. Our derived effective temperature and gravity are consistent with its identification as a red giant in Booetes I. Abundances for a further 15 elements have also been determined. Comparison of the relative abundances, [X/Fe], with those of the extremely metal-poor red giants of the Galactic halo shows that Boo-1137 is 'normal' with respect to C and N, the odd-Z elements Na and Al, the iron-peak elements, and the neutron-capture elements Sr and Ba, in comparison with the bulk of the Milky Way halo population having [Fe/H] {approx}<-3.0. The alpha-elements Mg, Si, Ca, and Ti are all higher by DELTA[X/Fe] {approx} 0.2 than the average halo values. Monte Carlo analysis indicates that DELTA[alpha/Fe] values this large are expected with a probability {approx}0.02. The elemental abundance pattern in Boo-1137 suggests inhomogeneous chemical evolution, consistent with the wide internal spread in iron abundances we previously reported. The similarity of most of the Boo-1137 relative abundances with respect to halo values, and the fact that the alpha-elements are all offset by a similar small amount from the halo averages, points to the same underlying galaxy-scale stellar initial mass function, but that Boo-1137 likely originated in a star-forming region where the abundances reflect either poor mixing of supernova (SN) ejecta, or poor sampling of the SN progenitor mass range, or both.

  16. Stoichiometry dependence of potential screening at La ( 1 - δ ) Al ( 1 + δ ) O 3 / SrTiO 3 interfaces

    SciTech Connect (OSTI)

    Weiland, Conan; Sterbinsky, George E.; Rumaiz, Abdul K.; Hellberg, C. Stephen; Woicik, Joseph C.; Zhu, Shaobo; Schlom, Darrell G.

    2015-04-03

    Hard x-ray photoelectron spectroscopy (HAXPES) and variable kinetic energy x-ray photoelectron spectroscopy (VKE-XPS) analyses have been performed on ten-unit-cell-thick La(1-δ)Al(1+δ)O₃ films, with La:Al ratios of 1.1, 1.0, and 0.9, deposited on SrTiO₃. Only Al-rich films are known to have a conductive interface. VKE-XPS, coupled with maximum entropy analysis, shows significant differences in the compositional depth profile among the Al-rich, La-rich, and stoichiometric films: significant La enrichment at the interface is observed in the La-rich and stoichiometric films, while the Al-rich film shows little to no intermixing. Additionally, the La-rich and stoichiometric films show a high concentration of Al at the surface, which is not observed in the Al-rich film. HAXPES valence band (VB) analysis shows a broadening of the VB for the Al-rich sample relative to the stoichiometric and La-rich samples. This broadening is consistent with an electric field across the Al-rich film. These results are consistent with a defect-driven electronic reconstruction.

  17. AL. I

    Office of Legacy Management (LM)

    AL. I Department of Energy Washington, DC 20545 OCT 13 Vii87 Mr. John T. Shields A214 National Fertilizer Development Center Tennessee Valley Authority Muscle Shoals, Alabama 35660 Dear Mr. Shields: As you may know, the Department of Energy (DOE) is evaluating the radiological condition of sites that were utilized under the Manhattan Engineer District and the Atomic Energy Commission (AEC) during the early years of nuclear development to determine whether they need remedial action and whether

  18. Using Encapsulated Phase Change Material in Thermal Energy Storage for Baseload Concentrating Solar Power (EPCM-TES)

    SciTech Connect (OSTI)

    Mathur, Anoop

    2013-12-15

    Terrafore successfully demonstrated and optimized the manufacturing of capsules containing phase-changing inorganic salts. The phase change was used to store thermal energy collected from a concentrating solar-power plant as latent heat. This latent heat, in addition to sensible heat increased the energy density (energy stored per unit weight of salt) by over 50%, thus requiring 40% less salt and over 60% less capsule container. Therefore, the cost to store high-temperature thermal energy collected in a concentrating solar power plant will be reduced by almost 40% or more, as compared to conventional two-tank, sensible-only storage systems. The cost for thermal energy storage (TES) system is expected to achieve the Sun Shot goal of $15 per kWh(t). Costs associated with poor heat-transfer in phase change materials (PCM) were also eliminated. Although thermal energy storage that relies on the latent heat of fusion of PCM improves energy density by as much as 50%, upon energy discharge the salt freezes and builds on the heat transfer surfaces. Since these salts have low thermal conductivity, large heat-transfer areas, or larger conventional heat-exchangers are needed, which increases costs. By encapsulating PCM in small capsules we have increased the heat transfer area per unit volume of salt and brought the heat transfer fluid in direct contact with the capsules. These two improvements have increased the heat transfer coefficient and boosted heat transfer. The program was successful in overcoming the phenomenon of melt expansion in the capsules, which requires the creation of open volume in the capsules or shell to allow for expansion of the molten salt on melting and is heated above its melting point to 550°C. Under contract with the Department of Energy, Terrafore Inc. and Southwest Research Institute, developed innovative method(s) to economically create the open volume or void in the capsule. One method consists of using a sacrificial polymer coating as the

  19. A=16Mg (1993TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    93TI07) (Not observed) See (1986AN07

  20. A=16Na (1993TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    93TI07) (Not observed) See (1986AN07

  1. A=16Si (1993TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    93TI07) (Not observed) See (1986AN07

  2. A=19Be (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    95TI07) (Not observed) See (1983ANZQ

  3. A=19He (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    95TI07) (Not observed) See (1983ANZQ

  4. A=19Li (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    95TI07) (Not observed) See (1983ANZQ

  5. Microstructural studies on cast Zr[sub 3]Al-3wt%Nb

    SciTech Connect (OSTI)

    Tewari, R.; Dey, G.K.; Mukhopadhyay, P.; Banerjee, S. . Metallurgy Div.)

    1994-05-01

    In the binary Zr-Al system, Zr[sub 3]Al is the intermetallic phase richest in zirconium. In view of its low absorption cross section for thermal neutrons and its good strength and corrosion resistance, Zr[sub 3]Al may have possible applications as a structural material in thermal reactors. This phase has the ordered cubic L1[sub 2] structure and forms through the peritectoid reaction: [beta]-Zr + Zr[sub 2]Al[minus] > Zr[sub 3]Al, the reaction temperature being 1,292 K. Structurally Zr[sub 3]Al is quite similar to the [alpha][sub 2] or the Ti[sub 3]Al phase (ordered hexagonal DO[sub 19] structure) in the Ti-Al system, the two structures differing only in the stacking sequence of the close packed atomic layers. But for its inherent brittleness, Ti[sub 3]Al is a promising structural material for aerospace applications. It has, however, been demonstrated that niobium additions can reduce the brittleness of this phase. Studies on the Ti[sub 3]Al-Nb system have also shown that niobium stabilizes the high temperature [beta] phase (bcc structure) which, on cooling, can decompose through various phase reactions, generating some interesting microstructures. Similar studies on the Zr[sub 3]Al-Nb system have not been reported yet. The present paper describes some microstructural observations made on a cast Zr[sub 3]Al-3wt%Nb alloy.

  6. ALS Communications Group

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Communications Group Print From left: Ashley White, Lori Tamura, Keri Troutman, and Carina Braun. The ALS Communications staff maintain the ALS Web site; write and edit all...

  7. A=6n (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (Not illustrated) 6n has not been observed. See (1979AJ01, 1988AJ01) and references cited there. More recently (1990AL40) reports a search for 6n in a 14C(7Li, 6n) activation experiment at E(7Li) = 82 MeV. No evidence for 6n was obtained. The method of angular potential functions was used by (1989GO18) in a calculation of the properties of multi-neutron systems which indicated that these systems have no bound states. The ground state energy of a six-neutron drop has been computed with

  8. Effects of Point Defects and Impurities on Kinetics in NaAlH4 | Department

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    of Energy Point Defects and Impurities on Kinetics in NaAlH4 Effects of Point Defects and Impurities on Kinetics in NaAlH4 A presentation showing that point defects play an important role in the kinetics of NaAlH4 including vacancies and interstitials consistent with observed effects of Ti. effects_of_point_defects.pdf (503.7 KB) More Documents & Publications Catalytic Effect of Ti for Hydrogen Cycling in NaAlH4 FTA - SunLine Transit Agency - Final Report Proceedings of the 1998 U.S. DOE

  9. TES for Residential Settings

    SciTech Connect (OSTI)

    Rutberg, Michael; Hastbacka, Mildred; Bouza, Antonio

    2013-07-31

    The article discusses thermal energy storage approaches for residential buildings. This article addresses both brick bank storage and phase change material technologies. The energy savings and market potential of these thermal energy storage methods are reviewed as well.

  10. ALS User Meeting

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    User Meeting ALS User Meeting web banner ALS User Meeting: October 5-7, 2015 Home Agenda Awards Exhibitors Lodging Posters Registration Transportation Workshops Contact Us User...

  11. ALS User Meeting

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS User Meeting Print web banner ALS User Meeting: October 5-7, 2015 Home Agenda Awards Exhibitors Lodging Posters Registration Transportation Workshops Contact Us User Meeting...

  12. ALS Users' Association Charter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Source (ALS) at the Lawrence Berkeley Laboratory (LBL) for their research and the ALS management, as well as to provide a channel for communication with other synchrotron...

  13. ALS User Meeting

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS User Meeting October 3-5, 2011 Lawrence Berkeley National Laboratory, California

  14. A=6H (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (See the Isobar Diagram for 6H) 6H was reported in the 7Li(7Li, 8B)6H reaction at E(7Li) = 82 MeV (1984AL08, 1985AL1G) [σ(θ) ~ 60 nb/sr at θ = 10°] and in the 9Be(11B, 14O)6H reaction at E(11B) = 88 MeV (1986BE35) [σ(θ) ~ 16 nb/sr at θ ~ 8°]. 6H is unstable with respect to breakup into 3H + 3n by 2.7 ± 0.4 MeV, Γ = 1.8 ± 0.5 MeV (1984AL08), 2.6 ± 0.5 MeV, Γ = 1.3 ± 0.5 MeV (1986BE35). The value adopted in the previous review (1988AJ01) is 2.7 ± 0.3 MeV, Γ = 1.6 ± 0.4

  15. ALS Chemistry Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Chemistry Lab Print ALS Chemistry Labs The ALS Chemistry Labs are located in the User Support Building (15-130) and in Building 6 (6-2233)*. These spaces are dedicated for chemistry work that involves higher quantities, higher toxicity or reactivity, and/or more complex work activity than is allowed on the ALS experiment floor. In addition, the great majority of hazardous chemicals at the ALS are stored in these facilities. Standard chemical safety engineering, administrative and PPE

  16. ALS Chemistry Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Chemistry Lab Print ALS Chemistry Labs The ALS Chemistry Labs are located in the User Support Building (15-130) and in Building 6 (6-2233)*. These spaces are dedicated for chemistry work that involves higher quantities, higher toxicity or reactivity, and/or more complex work activity than is allowed on the ALS experiment floor. In addition, the great majority of hazardous chemicals at the ALS are stored in these facilities. Standard chemical safety engineering, administrative and PPE

  17. A=10F (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (Not illustrated) Not observed: see (1979AJ01). See also (1988AJ01

  18. A=10Ne (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (Not illustrated) Not observed: see (1979AJ01). See also (1988AJ01

  19. A=10O (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (Not illustrated) Not observed: see (1979AJ01). See also (1988AJ01

  20. A=17He (1993TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    93TI07) (Not illustrated) Not observed: see (1986AJ04, 1988POZS

  1. A=17Li (1993TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    93TI07) (Not illustrated) Not observed: see (1986AJ04, 1988POZS

  2. A=17Mg (1993TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Mg (1993TI07) (Not observed) See (1983ANZQ, 1988WA18, 1992AV03).

  3. A=17P (1993TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    93TI07) (Not observed) See (1983ANZQ, 1988WA18, 1992AV03

  4. A=17Si (1993TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Si (1993TI07) (Not observed) See (1983ANZQ, 1988WA18, 1992AV03).

  5. A=18He (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    95TI07) (Not illustrated) Not observed: See (1982AV1A, 1983ANZQ

  6. A=20Be (1998TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    98TI06) (Not observed) See (1977CE05, 1983ANZQ, 1986AN07, 1987SIZX

  7. A=20n (1998TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    98TI06) (Not observed) See (1977CE05, 1983ANZQ, 1986AN07, 1987SIZX

  8. A=20O (1998TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    98TI06) (See Energy Level Diagrams for 20O) GENERAL: See Table Prev. Table 20.1 preview 20.1 [General Table] (in PDF or PS) and Table Prev. Table 20.2 preview 20.2 [Table of Energy Levels] (in PDF or PS) here. 1. 20O(β-)20F Qm = 3.814 20O decays with a half-life of 13.51 ± 0.05 s to the 1+ states 20F*(1.06, 3.49) with branching ratios (99.973 ± 0.003) and (0.027 ± 0.003)%, log f0t = 3.740 ± 0.006 and 3.65 ± 0.06, respectively (1987AL06). Upper limits for the branching to other states of

  9. A=7H (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (Not illustrated) 7H has not been observed. Attempts have been made to detect it in the spontaneous fission of 252Cf (1982AL33) and in the 7Li(π-, π+) reaction [see (1984AJ01)]. A study of 9Be(π-, 2p) (1987GO25) found no evidence for 7H. See also the review of (1989OG1B) and the 7Li(π-, π+) investigation reported in (1989GR06). The ground state is calculated to have Jπ = 1/2+ and to be unstable with respect to 1n, 2n, 3n and 4n emission. Excited states are predicted at 4.84, 5.00

  10. ALS Chemistry Lab

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Chemistry Lab Print ALS Chemistry Labs The ALS Chemistry Labs are located in the User Support Building (15-130) and in Building 6 (6-2233)*. These spaces are dedicated for chemistry work that involves higher quantities, higher toxicity or reactivity, and/or more complex work activity than is allowed on the ALS experiment floor. In addition, the great majority of hazardous chemicals at the ALS are stored in these facilities. Standard chemical safety engineering, administrative and PPE controls

  11. Tuning band alignment using interface dipoles at the Pt/anatase TiO2 interface

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tachikawa, Takashi; Minohara, Makoto; Hikita, Yasuyuki; Bell, Christopher; Hwang, Harold Y.

    2015-10-27

    The Schottky barrier heights at the Pt/TiO2 (001) junctions are modulated over 0.8 eV by inserting <1 nm of LaAlO3. The large electric field in the LaAlO3 is stabilized by preserving the continuity of in-plane lattice symmetry at the oxide interface. Lastly, these results greatly expand the application of dipole engineering to versatile polycrystalline metal/binary oxide functional interfaces.

  12. Microstructural evaluation of NiTi-based films deposited by magnetron sputtering

    SciTech Connect (OSTI)

    Crăciunescu, Corneliu M. Mitelea, Ion Budău, Victor; Ercuţa, Aurel

    2014-11-24

    Shape memory alloy films belonging to the NiTi-based systems were deposited on heated and unheated substrates, by magnetron sputtering in a custom made system, and their structure and composition was analyzed using electron microscopy. Several substrates were used for the depositions: glass, Cu-Zn-Al, Cu-Al-Ni and Ti-NiCu shape memory alloy ribbons and kapton. The composition of the Ti-Ni-Cu films showed limited differences, compared to the one of the target and the microstructure for the DC magnetron sputtering revealed crystallized structure with features determined on peel off samples from a Si wafer. Both inter and transcrystalline fractures were observed and related to the interfacial stress developed on cooling from deposition temperature.

  13. ELEMENTAL ABUNDANCES AND THEIR IMPLICATIONS FOR THE CHEMICAL ENRICHMENT OF THE BOOeTES I ULTRAFAINT GALAXY

    SciTech Connect (OSTI)

    Gilmore, Gerard; Norris, John E.; Yong, David; Monaco, Lorenzo; Wyse, Rosemary F. G.; Geisler, D. E-mail: jen@mso.anu.edu.au E-mail: lmonaco@eso.org E-mail: dgeisler@astro-udec.cl

    2013-01-20

    We present a double-blind analysis of high-dispersion spectra of seven red giant members of the Booetes I ultrafaint dwarf spheroidal galaxy, complemented with re-analysis of a similar spectrum of an eighth-member star. The stars cover [Fe/H] from -3.7 to -1.9 and include a CEMP-no star with [Fe/H] = -3.33. We conclude from our chemical abundance data that Booetes I has evolved as a self-enriching star-forming system, from essentially primordial initial abundances. This allows us uniquely to investigate the place of CEMP-no stars in a chemically evolving system, in addition to limiting the timescale of star formation. The elemental abundances are formally consistent with a halo-like distribution, with enhanced mean [{alpha}/Fe] and small scatter about the mean. This is in accord with the high-mass stellar initial mass function in this low-stellar-density, low-metallicity system being indistinguishable from the present-day solar neighborhood value. There is a non-significant hint of a decline in [{alpha}/Fe] with [Fe/H]; together with the low scatter, this requires low star formation rates, allowing time for supernova ejecta to be mixed over the large spatial scales of interest. One star has very high [Ti/Fe], but we do not confirm a previously published high value of [Mg/Fe] for another star. We discuss the existence of CEMP-no stars, and the absence of any stars with lower CEMP-no enhancements at higher [Fe/H], a situation that is consistent with knowledge of CEMP-no stars in the Galactic field. We show that this observation requires there be two enrichment paths at very low metallicities: CEMP-no and 'carbon-normal'.

  14. Access to the ALS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Gate Access Access to the ALS Print User Access The ALS experiment floor (Building 6) is a Controlled Access Area for radiation protection. All ALS users are required to register with the ALS User Services Office and take safety training (see Complete Safety Training ) before they are issued a Berkeley Lab ID badge and granted access to the facility. Note: Users arriving at the ALS outside registration business hours (Monday-Friday 8:00 a.m.-4:00 p.m.) must notify the User Office in advance and

  15. ALS Activity Reports

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Activity Reports Print These hard-copy annual reports were produced from 1993-2006. They illustrated the depth and breadth of the ALS scientific program with a selection of research results. They also summarized operations and ongoing R&D, highlighted educational outreach efforts and special events, and provided yearly documentation of the beamlines and publications. The Activity Report was replaced in 2007 by ALS Spectrum. The reports for 1996-2006 are available here. Activity Report

  16. ALS Communications Group

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Communications Group Print From left: Ashley White, Lori Tamura, and Keri Troutman. The ALS Communications staff maintain the ALS Web site; write and edit all print and electronic publications for the ALS, including Science Highlights, Science Briefs, brochures, handouts, and the monthly newsletter ALSNews; and create educational and scientific outreach materials. In addition, members of the group organize bi-monthly Science Cafés, create conference and workshop Web sites and publicity, and

  17. ALS Postdoctoral Fellowship Highlights

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Postdoctoral Fellowship Highlights Print Since its inception in 2005, the ALS Postdoctoral Fellowship program has supported young scientists in new and ongoing research projects at the ALS. In many cases, the postdoctoral fellows were also supported by collaborating institutions. These postdoc "highlights" -listed chronologically-feature a description of their projects while at the ALS, resulting publications, and their current positions and research activities. Name Year/Beamline

  18. ALS Users' Association Charter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Users' Executive Committee ALS Users' Association Charter Print The purpose of the Advanced Light Source Users' Association (ALSUA) is to provide an organized framework for the interaction between those who use the Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory (LBL) for their research and the ALS management, as well as to provide a channel for communication with other synchrotron radiation laboratories and, on suitable occasions, with federal agencies. The ALSUA, representing

  19. ALS Beamlines Directory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Beamlines Directory ALS Beamlines Directory Print Monday, 31 August 2009 08:16 Beamlines, Parameters, Contact Information, and Schedules Click on the image to see/download a high-resolution version of the ALS beamclock. Beamline Parameters Beamline and endstation technical information is available through the links below. Unless otherwise noted, all beamlines are currently operational. Individual beamline schedules are posted when available. Please contact the responsible beamline scientist

  20. ALS Biosciences Crosscutting Review

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Biosciences Crosscutting Review ALS Biosciences Crosscutting Review Print by Steve Kevan and Corie Ralston The ALS organized and recently held a two-day crosscutting review of its bioscience programs. The ALS Scientific Advisory Committee (SAC) sponsors these reviews, which are intended to evaluate the performance of entire research subdisciplines served by the facility and to motivate strategic thinking about capabilities and research directions that are ripe for future development. SAC member

  1. ALS Communications Group

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Communications Group Print From left: Ashley White, Lori Tamura, and Keri Troutman. The ALS Communications staff maintain the ALS Web site; write and edit all print and electronic publications for the ALS, including Science Highlights, Science Briefs, brochures, handouts, and the monthly newsletter ALSNews; and create educational and scientific outreach materials. In addition, members of the group organize bi-monthly Science Cafés, create conference and workshop Web sites and publicity, and

  2. ALS Users' Association Charter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Users' Association Charter Print The purpose of the Advanced Light Source Users' Association (ALSUA) is to provide an organized framework for the interaction between those who use the Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory (LBL) for their research and the ALS management, as well as to provide a channel for communication with other synchrotron radiation laboratories and, on suitable occasions, with federal agencies. The ALSUA, representing the research workers, will

  3. A=20He (1998TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    He (1998TI06) (Not observed) See (1977CE05, 1983ANZQ, 1986AN07, 1987SIZX).

  4. A=20Li (1998TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Li (1998TI06) (Not observed) See (1977CE05, 1983ANZQ, 1986AN07, 1987SIZX).

  5. A=5n (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (Not illustrated) See also the A = 5 introductory discussion titled A = 5 resonance parameters.

  6. Access to the ALS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS User Services Office and take safety training (see Complete Safety Training ) before ... the User Office in advance and have all their online forms completed before their arrival. ...

  7. 2013 ALS User Meeting

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    3 ALS User Meeting banner Home Agenda Awards Exhibitors Lodging Posters Registration T-Shirt Contest Transportation Workshops Contact Us User Meeting Archives Users' Executive...

  8. 2013 ALS User Meeting

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2013 ALS User Meeting Print banner Home Agenda Awards Exhibitors Lodging Posters Registration T-Shirt Contest Transportation Workshops Contact Us User Meeting Archives Users'...

  9. TiN coated aluminum electrodes for DC high voltage electron guns

    SciTech Connect (OSTI)

    Mamun, Md Abdullah A.; Elmustafa, Abdelmageed A.; Taus, Rhys; Forman, Eric; Poelker, Matthew

    2015-05-15

    Preparing electrodes made of metals like stainless steel, for use inside DC high voltage electron guns, is a labor-intensive and time-consuming process. In this paper, the authors report the exceptional high voltage performance of aluminum electrodes coated with hard titanium nitride (TiN). The aluminum electrodes were comparatively easy to manufacture and required only hours of mechanical polishing using silicon carbide paper, prior to coating with TiN by a commercial vendor. The high voltage performance of three TiN-coated aluminum electrodes, before and after gas conditioning with helium, was compared to that of bare aluminum electrodes, and electrodes manufactured from titanium alloy (Ti-6Al-4V). Following gas conditioning, each TiN-coated aluminum electrode reached −225 kV bias voltage while generating less than 100 pA of field emission (<10 pA) using a 40 mm cathode/anode gap, corresponding to field strength of 13.7 MV/m. Smaller gaps were studied to evaluate electrode performance at higher field strength with the best performing TiN-coated aluminum electrode reaching ∼22.5 MV/m with field emission less than 100 pA. These results were comparable to those obtained from our best-performing electrodes manufactured from stainless steel, titanium alloy and niobium, as reported in references cited below. The TiN coating provided a very smooth surface and with mechanical properties of the coating (hardness and modulus) superior to those of stainless steel, titanium-alloy, and niobium electrodes. These features likely contributed to the improved high voltage performance of the TiN-coated aluminum electrodes.

  10. Infrared spectroscopy of CaTiO3, SrTiO3, BaTiO3, Ba0.5Sr0.5TiO3...

    Office of Scientific and Technical Information (OSTI)

    Infrared spectroscopy of CaTiO3, SrTiO3, BaTiO3, Ba0.5Sr0.5TiO3 thin films, and (BaTiO3)5(SrTiO3)5 superlattice grown on SrRuO3SrTiO3(001) substrates Citation Details In-Document ...

  11. Access to the ALS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    are required to register with the ALS User Services Office and take safety training (see Complete Safety Training ) before they are issued a Berkeley Lab ID badge and granted...

  12. ALS in the News

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the ALS is well represented) New Lithium-Ion Battery Discovery Contradicts ... of water-no deeper than a few molecules-to the surface of a barium fluoride crystal. ...

  13. ALS Staff Photo

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    On May 14, 2013, members of ALS staff posed for a group photo in front of the dome. A hi-res version can be downloaded here. The last staff photo was taken in 2006. 2013 staff...

  14. ALS Communications Group

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    organize bi-monthly Science Cafs, create conference and workshop Web sites and publicity, and coordinate ALS participation in Lab-wide events such as the Berkeley Lab Open...

  15. ALS Users' Association Charter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    facility. Thorough discussion with users of current projects, as well as plans for the future, will place ALS management in a better position to evaluate the needs of users and...

  16. ALS Activity Reports

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Activity Reports Print These hard-copy annual reports were produced from 1993-2006. They illustrated the depth and breadth of the ALS scientific program with a selection of research results. They also summarized operations and ongoing R&D, highlighted educational outreach efforts and special events, and provided yearly documentation of the beamlines and publications. The Activity Report was replaced in 2007 by ALS Spectrum. The reports for 1996-2006 are available here. Activity Report 2006

  17. ALS Beamlines Directory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Beamlines Directory Print Beamlines, Parameters, Contact Information, and Schedules Click on the image to see/download a high-resolution version of the ALS beamclock. Beamline Parameters Beamline and endstation technical information is available through the links below. Unless otherwise noted, all beamlines are currently operational. Individual beamline schedules are posted when available. Please contact the responsible beamline scientist for additional schedule information. When calling

  18. ALS in the News

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in the News Print Recent Articles Featuring ALS Staff and Science 2015 February New Video: Berkeley Lab's "Who We Are" Grants Give Particle Accelerator Technologies a Boost Details on Presidential Budget Request for DOE R&D DOE Scientists Team up to Demonstrate Scientific Potential of Big Data Infrastructure January Timeline Chronicles Lab's Science Highlights in 2014 (...and the ALS is well represented!) New Lithium-Ion Battery Discovery Contradicts Everything You Thought You Knew

  19. ALS Activity Reports

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Activity Reports Print These hard-copy annual reports were produced from 1993-2006. They illustrated the depth and breadth of the ALS scientific program with a selection of research results. They also summarized operations and ongoing R&D, highlighted educational outreach efforts and special events, and provided yearly documentation of the beamlines and publications. The Activity Report was replaced in 2007 by ALS Spectrum. The reports for 1996-2006 are available here. Activity Report 2006

  20. ALS Activity Reports

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Activity Reports Print These hard-copy annual reports were produced from 1993-2006. They illustrated the depth and breadth of the ALS scientific program with a selection of research results. They also summarized operations and ongoing R&D, highlighted educational outreach efforts and special events, and provided yearly documentation of the beamlines and publications. The Activity Report was replaced in 2007 by ALS Spectrum. The reports for 1996-2006 are available here. Activity Report 2006

  1. ALS Beamlines Directory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Beamlines Directory Print Beamlines, Parameters, Contact Information, and Schedules Click on the image to see/download a high-resolution version of the ALS beamclock. Beamline Parameters Beamline and endstation technical information is available through the links below. Unless otherwise noted, all beamlines are currently operational. Individual beamline schedules are posted when available. Please contact the responsible beamline scientist for additional schedule information. When calling

  2. ALS Beamlines Directory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Beamlines Directory Print Beamlines, Parameters, Contact Information, and Schedules Click on the image to see/download a high-resolution version of the ALS beamclock. Beamline Parameters Beamline and endstation technical information is available through the links below. Unless otherwise noted, all beamlines are currently operational. Individual beamline schedules are posted when available. Please contact the responsible beamline scientist for additional schedule information. When calling

  3. ALS User Meeting Archives

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS User Meeting Archives Print Past User Meeting Programs, Workshops, and Awards Year David A. Shirley (Science) Klaus Halbach (Instrumentation) Tim Renner (Service) 2015 Program Workshops Wanli Yang, "For new concepts optimizing battery materials with the aid of soft x-ray microscopy." Hans Bechtel, Michael Martin, and Markus Raschke, "For the development of Synchrotron Infrared Nano Spectroscopy (SINS)." David Malone. "As the first person all 2400 ALS users contact

  4. ALS Users' Association Charter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Users' Association Charter Print The purpose of the Advanced Light Source Users' Association (ALSUA) is to provide an organized framework for the interaction between those who use the Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory (LBL) for their research and the ALS management, as well as to provide a channel for communication with other synchrotron radiation laboratories and, on suitable occasions, with federal agencies. The ALSUA, representing the research workers, will be in

  5. ALS Users' Association Charter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Users' Association Charter Print The purpose of the Advanced Light Source Users' Association (ALSUA) is to provide an organized framework for the interaction between those who use the Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory (LBL) for their research and the ALS management, as well as to provide a channel for communication with other synchrotron radiation laboratories and, on suitable occasions, with federal agencies. The ALSUA, representing the research workers, will be in

  6. Emission mechanisms in Al-rich AlGaN/AlN quantum wells assessed by excitation power dependent photoluminescence spectroscopy

    SciTech Connect (OSTI)

    Iwata, Yoshiya; Banal, Ryan G.; Ichikawa, Shuhei; Funato, Mitsuru; Kawakami, Yoichi

    2015-02-21

    The optical properties of Al-rich AlGaN/AlN quantum wells are assessed by excitation-power-dependent time-integrated (TI) and time-resolved (TR) photoluminescence (PL) measurements. Two excitation sources, an optical parametric oscillator and the 4th harmonics of a Ti:sapphire laser, realize a wide range of excited carrier densities between 10{sup 12} and 10{sup 21 }cm{sup −3}. The emission mechanisms change from an exciton to an electron-hole plasma as the excitation power increases. Accordingly, the PL decay time is drastically reduced, and the integrated PL intensities increase in the following order: linearly, super-linearly, linearly again, and sub-linearly. The observed results are well accounted for by rate equations that consider the saturation effect of non-radiative recombination processes. Using both TIPL and TRPL measurements allows the density of non-radiative recombination centers, the internal quantum efficiency, and the radiative recombination coefficient to be reliably extracted.

  7. Electrostatic analysis of n-doped SrTiO{sub 3} metal-insulator-semiconductor systems

    SciTech Connect (OSTI)

    Kamerbeek, A. M. Banerjee, T.; Hueting, R. J. E.

    2015-12-14

    Electron doped SrTiO{sub 3}, a complex-oxide semiconductor, possesses novel electronic properties due to its strong temperature and electric-field dependent permittivity. Due to the high permittivity, metal/n-SrTiO{sub 3} systems show reasonably strong rectification even when SrTiO{sub 3} is degenerately doped. Our experiments show that the insertion of a sub nanometer layer of AlO{sub x} in between the metal and n-SrTiO{sub 3} interface leads to a dramatic reduction of the Schottky barrier height (from around 0.90 V to 0.25 V). This reduces the interface resistivity by 4 orders of magnitude. The derived electrostatic analysis of the metal-insulator-semiconductor (n-SrTiO{sub 3}) system is consistent with this trend. When compared with a Si based MIS system, the change is much larger and mainly governed by the high permittivity of SrTiO{sub 3}. The non-linear permittivity of n-SrTiO{sub 3} leads to unconventional properties such as a temperature dependent surface potential non-existent for semiconductors with linear permittivity such as Si. This allows tuning of the interfacial band alignment, and consequently the Schottky barrier height, in a much more drastic way than in conventional semiconductors.

  8. Magnetic Hardening of CeFe11Ti and the Effect of TiC Addition...

    Office of Scientific and Technical Information (OSTI)

    Magnetic Hardening of CeFe11Ti and the Effect of TiC Addition Citation ... Publication Date: 2015-04-01 OSTI Identifier: 1221660 Report Number(s): IS-J 8423 Journal ID: ISSN ...

  9. AL2007-08.doc

    Broader source: Energy.gov (indexed) [DOE]

    Assessment Tool, IEEE Standard 1680-2006 for Environmental Assessment of Personal Computer Products. When is this Acquisition Letter (AL) Effective? This AL is effective...

  10. 2012 ALS User Meeting Awards

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2012 ALS User Meeting Awards Print Recipients of the 2012 Users' Executive Committee awards and Student Poster Competition were announced Tuesday, October 9, at the ALS User...

  11. 2012 ALS User Meeting Awards

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2 ALS User Meeting Awards Recipients of the 2012 Users' Executive Committee awards and Student Poster Competition were announced Tuesday, October 9, at the ALS User Meeting. David...

  12. AL PRO | Open Energy Information

    Open Energy Info (EERE)

    search Name: AL-PRO Place: Grossheide, Lower Saxony, Germany Zip: 26532 Sector: Wind energy Product: AL-PRO is an inndependent expert office for wind forecasts, wind...

  13. A=16Li (1993TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Li (1993TI07) (Not illustrated) This nucleus has not been observed. Shell model studies (1988POZS) are used to predict J and the magnetic dipole moment....

  14. A=16He (1993TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    93TI07) (Not illustrated) This nucleus has not been observed. See (1982AV1A, 1983ANZQ, 1986AJ04

  15. A=19Mg (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Mg (1995TI07) (Not observed) See (1987AJ02) and (1987GU1K, 1987PO01, 1993HI08

  16. Science DMZ for ALS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Science Engagement Move your data Programs & Workshops Science Requirements Reviews Case Studies OSCARS Case Studies Science DMZ Case Studies Science DMZ @ UF Science DMZ @ CU Science DMZ @ Penn & VTTI Science DMZ @ NOAA Science DMZ @ NERSC Science DMZ @ ALS Multi-facility Workflow Case Study Contact Us Technical Assistance: 1 800-33-ESnet (Inside US) 1 800-333-7638 (Inside US) 1 510-486-7600 (Globally) 1 510-486-7607 (Globally) Report Network Problems: trouble@es.net Provide Web

  17. Femtosecond laser-induced periodic surface structure on the Ti-based nanolayered thin films

    SciTech Connect (OSTI)

    Petrovi?, Suzana M.; Gakovi?, B.; Peruko, D.; Stratakis, E.; Department of Materials Science and Technology, University of Crete, 710 03 Heraklion, Crete ; Bogdanovi?-Radovi?, I.; ?ekada, M.; Fotakis, C.; Department of Physics, University of Crete, 714 09 Heraklion, Crete ; Jelenkovi?, B.

    2013-12-21

    Laser-induced periodic surface structures (LIPSSs) and chemical composition changes of Ti-based nanolayered thin films (Al/Ti, Ni/Ti) after femtosecond (fs) laser pulses action were studied. Irradiation is performed using linearly polarized Ti:Sapphire fs laser pulses of 40 fs pulse duration and 800 nm wavelength. The low spatial frequency LIPSS (LSFL), oriented perpendicular to the laser polarization with periods slightly lower than the irradiation wavelength, was typically formed at elevated laser fluences. On the contrary, high spatial frequency LIPSS (HSFL) with uniform period of 155 nm, parallel to the laser light polarization, appeared at low laser fluences, as well as in the wings of the Gaussian laser beam distribution for higher used fluence. LSFL formation was associated with the material ablation process and accompanied by the intense formation of nanoparticles, especially in the Ni/Ti system. The composition changes at the surface of both multilayer systems in the LSFL area indicated the intermixing between layers and the substrate. Concentration and distribution of all constitutive elements in the irradiated area with formed HSFLs were almost unchanged.

  18. ALS Staff Photo

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Staff Photo Print On May 14, 2013, members of ALS staff posed for a group photo in front of the dome. A hi-res version can be downloaded here. The last staff photo was taken in 2006. 2013 staff photo

  19. ALS Collaborative Postdoctoral Fellowship Program

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Collaborative Postdoctoral Fellowship Program ALS Collaborative Postdoctoral Fellowship Program Print Monday, 19 July 2010 15:13 The Advanced Light Source (ALS) Collaborative Postdoctoral Fellowship program provides challenging opportunities to conduct research and instrument development in areas supporting the scientific programs of the Department of Energy (DOE), Lawrence Berkeley National Laboratory (LBNL), and the ALS that include physical, chemical, material, energy, environmental,

  20. Recovery of Li from alloys of Al- Li and Li- Al using engineered scavenger compounds

    DOE Patents [OSTI]

    Riley, W. D.; Jong, B. W.; Collins, W. K.; Gerdemann, S. J.

    1994-01-01

    A method of producing lithium of high purity from lithium aluminum alloys using an engineered scavenger compound, comprising: I) preparing an engineered scavenger compound by: a) mixing and heating compounds of TiO2 and Li2CO3 at a temperature sufficient to dry the compounds and convert Li.sub.2 CO.sub.3 to Li.sub.2 O; and b) mixing and heating the compounds at a temperature sufficient to produce a scavenger Li.sub.2 O.3TiO.sub.2 compound; II) loading the scavenger into one of two electrode baskets in a three electrode cell reactor and placing an Al-Li alloy in a second electrode basket of the three electrode cell reactor; III) heating the cell to a temperature sufficient to enable a mixture of KCl-LiCl contained in a crucible in the cell to reach its melting point and become a molten bath; IV) immersing the baskets in the bath until an electrical connection is made between the baskets to charge the scavenger compound with Li until there is an initial current and voltage followed by a fall off ending current and voltage; and V) making a connection between the basket electrode containing engineered scavenger compound and a steel rod electrode disposed between the basket electrodes and applying a current to cause Li to leave the scavenger compound and become electrodeposited on the steel rod electrode.

  1. ALS Holds Annual Safety Day

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Holds Annual Safety Day ALS Holds Annual Safety Day Print by Scott Taylor, ALS Safety Manager Andrew Doran cleans equipment housing at Beamline 12.2.2. The ALS held its annual safety day on Monday, June 13 for all ALS and associated staff. The day started with an all-hands meeting, beginning with presentations by ALS Director Roger Falcone and LBNL Environmental Health and Safety Division Director (and former ALS Safety Manager) Jim Floyd. Both discussed the importance of the incorporation

  2. ALS Beamlines Directory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Beamlines Directory Print Beamlines, Parameters, Contact Information, and Schedules Click on the image to see/download a high-resolution version of the ALS beamclock. Beamline Parameters Beamline and endstation technical information is available through the links below. Unless otherwise noted, all beamlines are currently operational. Individual beamline schedules are posted when available. Please contact the responsible beamline scientist for additional schedule information. When calling from

  3. ALS User Meeting Archives

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Meeting Archives Past User Meeting Programs, Workshops, and Awards Year David A. Shirley (Science) Klaus Halbach (Instrumentation) Tim Renner (Service) 2015 Program Workshops Wanli Yang, "For new concepts optimizing battery materials with the aid of soft x-ray microscopy." Hans Bechtel, Michael Martin, and Markus Raschke, "For the development of Synchrotron Infrared Nano Spectroscopy (SINS)." David Malone. "As the first person all 2400 ALS users contact for their beam

  4. Microstructure and tribological performance of nanocomposite Ti-Si-C-N coatings deposited using hexamethyldisilazane precursor

    SciTech Connect (OSTI)

    Wei Ronghua; Rincon, Christopher; Langa, Edward; Yang Qi

    2010-09-15

    Thick nanocomposite Ti-Si-C-N coatings (20-30 {mu}m) were deposited on Ti-6Al-4V substrate by magnetron sputtering of Ti in a gas mixture of Ar, N{sub 2}, and hexamethyldisilazane (HMDSN) under various deposition conditions. Microstructure and composition of the coatings were studied using scanning electron microscopy, x-ray diffraction, and energy dispersive x-ray spectroscopy, while the mechanical and tribological properties of these coatings were studied using Rc indentation, and micro- and nanoindentations, solid particle erosion testing, and ball-on-disk wear testing. It has been observed that the Si concentration of these coatings is varied from 0% (TiN) to 15% (Ti-Si-C-N), while the structure of these coatings is similar to the nanocomposite Ti-Si-N coatings and consists of nanocrystalline B1 structured Ti(C,N) in an amorphous matrix of SiC{sub x}N{sub y} with the grain size of 5->100 nm, depending on the coating preparation process. These coatings exhibit excellent adhesion when subjected to Rc indentation tests. The microhardness of these coatings varies from 1200 to 3400 HV25, while the nanohardness varies from 10 to 26 GPa. Both the microhardness and nanohardness are slightly lower than those of similar coatings prepared using trimethylsilane. However, the erosion test using a microsand erosion tester at both 30 deg. and 90 deg. incident angles shows that these coatings have very high erosion resistance and up to a few hundred times of improvement has been observed. These coatings also exhibit very high resistance to sliding wear with a low coefficient of friction of about 0.2 in dry sliding. There are a few advantages of using the HMDSN precursor to prepare the Ti-Si-C-N coatings over conventional magnetron sputtered deposition of Ti-Si-N coatings including composition uniformity, precursor handling safety, and high deposition rate. The coatings can be applied to protect gas turbine compressor blades from solid particle erosion and steam turbine blades

  5. Upper limit to magnetism in LaAIO3/SrTiO3 heterostructures

    SciTech Connect (OSTI)

    Fitzsimmons, Michael R.; Hengartner, N. W.; Singh, S.; Zhernenkov, M.; Bruno, F. Y.; Santamaria, J.; Brinkman, A.; Huijben, M.; Molegraaf, H.; de la Venta, J.; Schuller, Ivan K.

    2012-02-27

    In 2004 Ohtomo and Hwang reported unusually high conductivity in LaAl03 and SrTi03 bilayer samples. Since then, metallic conduction, superconductivity, magnetism, and coexistence of superconductivity and ferromagnetism have been attributed to LaAl03/SrTi03 interfaces. Very recently, two studies have reported large magnetic moments attributed to interfaces from measurement techniques that are unable to distinguish between interfacial and bulk magnetism. Consequently, it is imperative to perform magnetic measurements that by being intrinsically sensitive to interface magnetism are impervious to experimental artifacts suffered by bulk measurements. Using polarized neutron reflectometry we measured the neutron spin dependent reflectivity from four LaAl03/SrTi03 superlattices. Our results indicate the upper limit for the magnetization averaged over the lateral dimensions of the sample induced by an 11 T magnetic field at 1.7 K is less than 2 G. SQUID magnetometry of the neutron superlattice samples sporadically finds an enhanced moment (consistent with past reports), possibly due to experimental artifacts. These observations set important restrictions on theories which imply a strongly enhanced magnetism at the interface between LaAI03 and SrTi03.

  6. The permeation behavior of deuterium through 1Cr18Ni9Ti stainless steel with TiN+TiC-TiN multiple films

    SciTech Connect (OSTI)

    Xiong, Y.; Song, J.; Luo, D.; Lei, Q.; Chen, C.

    2015-03-15

    The prevention of tritium losses via permeation through structure components is an important issue in fusion technology. The production of thin layers on materials with low diffusivity and/or low surface recombination constants (so-called permeation barriers) seems to be the most practical method to reduce or hinder the permeation of tritium through materials. TiN+TiC+TiN multiple films are deposited on the surface of 1Cr18Ni9Ti stainless steel by ion-beam assisted deposition technology. The characteristics of films are tested by XPS ASEM and XRD, which shows that the film are compact and uniform with a thickness of about 15 μm, and have a good adherence with the substrate below 773 K. The diffraction peaks in the XRD patterns for TiC and TiN are broadened, implying that the multiple films are deposited on the surface of 1Cr18Ni9Ti stainless steel. Meanwhile, the C-H bonded CH{sub 4}-appears in the infrared spectra of multiple films, suggesting that the CH{sub 4}- is in a static state, so hydrogen atom cannot migrate from the site bonded with carbon to a neighboring site. The measured deuterium permeability in 1Cr18Ni9Ti stainless steel coated with multiple films is 2-3 orders of magnitude lower than that of pure 1Cr18Ni9Ti stainless steel substrate from 473 K to 773 K. However, this barrier is partly destroyed above 773 K.

  7. Recovery of Li from alloys of Al-Li and Li-Al using engineered scavenger compounds

    SciTech Connect (OSTI)

    Riley, W.D.; Jong, B.W.; Collins, W.K.; Gerdemann, S.J.

    1992-01-01

    The invention relates to a process for obtaining Li metal selectively recovered from Li-Al or Al-Li alloy scrap by: (1) removing Li from aluminum-lithium alloys at temperatures between about 400 C-750 C in a molten salt bath of KC1-LiCl using lithium titanate (Li2O.3TiO2) as an engineered scavenger compound (ESC); and (2) electrodepositing of Li from the loaded ESC to a stainless steel electrode. By use of the second step, the ESC is prepared for reuse. A molten salt bath is required in the invention because of the inability of molten aluminum alloys to wet the ESC.

  8. ALS Doctoral Fellowship in Residence

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Doctoral Fellowship in Residence ALS Doctoral Fellowship in Residence Print Monday, 26 July 2010 09:21 The Advanced Light Source (ALS), a division of Lawrence Berkeley National Laboratory, is a national user facility that generates intense x-ray radiation for scientific and technological research. As the world's first third-generation synchrotron radiation source, the ALS offers outstanding performance in the VUV-soft x-ray energy range and excellent performance into the hard x-ray region.

  9. Crystal Structure and Thermodynamic Stability of Ba/Ti-Substituted Pollucites for Radioactive Cs/Ba Immobilization

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Xu, Hongwu; Chavez, Manuel E.; Mitchell, Jeremy N.; Garino, Terry J.; Schwarz, Haiqing L.; Rodriguez, Mark A.; Rademacher, David X.; Nenoff, Tina Maria

    2015-04-23

    An analogue of the mineral pollucite (CsAlSi2O6), CsTiSi2O6.5 has a potential host phase for radioactive Cs. However, as 137Cs and 135Cs transmute to 137Ba and 135Ba, respectively, through the beta decay, it is essential to study the structure and stability of this phase upon Cs → Ba substitution. In this work, two series of Ba/Ti-substituted samples, CsxBa(1-x)/2TiSi2O6.5 and CsxBa1-xTiSi2O7-0.5x, (x = 0.9 and 0.7), were synthesized by high-temperature crystallization from their respective precursors. Synchrotron X-ray diffraction and Rietveld analysis reveal that while CsxBa(1-x)/2TiSi2O6.5 samples are phase-pure, CsxBa1-xTiSi2O7-0.5x samples contain Cs3x/(2+x)Ba(1-x)/(2+x)TiSi2O6.5 pollucites (i.e., also two-Cs-to-one-Ba substitution) and a secondary phase, fresnoitemore » (Ba2TiSi2O8). Thus, the CsxBa1-xTiSi2O7-0.5x series is energetically less favorable than CsxBa(1-x)/2TiSi2O6.5. To study the stability systematics of CsxBa(1-x)/2TiSi2O6.5 pollucites, high-temperature calorimetric experiments were performed at 973 K with or without the lead borate solvent. Enthalpies of formation from the constituent oxides (and elements) have thus been derived. Our results show that with increasing Ba/(Cs + Ba) ratio, the thermodynamic stability of these phases decreases with respect to their component oxides. Hence, from the energetic viewpoint, continued Cs → Ba transmutation tends to destabilize the parent silicotitanate pollucite structure. However, the Ba-substituted pollucite co-forms with fresnoite (which incorporates the excess Ba), thereby providing viable ceramic waste forms for all the Ba decay products.« less

  10. Ti Leggett | Argonne Leadership Computing Facility

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Ti Leggett Deputy Project Directcor & Deputy Director of Operations Argonne National Laboratory 9700 S. Cass Avenue Building 240 - Room 3132 Argonne, IL 60439 630-252-1937 tleggett

  11. A=10C (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (See Energy Level Diagrams for 10C) GENERAL: References to articles on general properties of 10C published since the previous review (1988AJ01) are grouped into...

  12. A=10N (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (Not illustrated) GENERAL: References to articles on general properties of 10N published since the previous review (1988AJ01) are grouped into categories and listed,...

  13. A=10Li (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (See Energy Level Diagrams for 10Li) GENERAL: References to articles on general properties of 10Li published since the previous review (1988AJ01) are grouped into...

  14. A=10He (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (See Energy Level Diagrams for 10He) GENERAL: References to articles on general properties of 10He published since the previous review (1988AJ01) are grouped into...

  15. A=18Li (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Li (1995TI07) (Not illustrated) 18Li has not been observed. Shell model calculations described in (1988POZS) predict the ground-state magentic dipole moment and charge and matter radii.

  16. A=18Mg, etc. (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    95TI07) (Not observed) See (1986AN07) and (1983ANZQ). See also the results of calculations of β+/electron capture half lives for neutron deficient nuclei in (1993HI08

  17. A=6B (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (Not illustrated) Not observed: see ( 1984AJ01, 1989GR06 [6Li(π+, π-) at Eπ+ = 180, 240 MeV], 1993PO11 [properties of exotic light nuclei]) (1998SU18

  18. A=6C (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (Not illustrated) Not observed: see (1979AJ01, 1984AJ01, 1989GR06 [6Li(π+, π-) at Eπ+ = 180, 240 MeV], 1993PO11 [properties of exotic light nuclei]) (1998SU18

  19. A=20B (1998TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    98TI06) (Not observed) The mass excess of 20B is predicted to be 69.08 MeV (1974TH01). 20B is then unstable with respect to breakup into 19B + n by 0.9 MeV: see 19B in (1995TI07) and (1978AJ03, 1983ANZQ) and see the work on effective interactions for the (0p1s0d) nuclear shell-model space (1992WA22

  20. Aluminum Stabilized NbTi Conductor Test Coil Design, Fabrication, and Test Results

    SciTech Connect (OSTI)

    Andreev, N.; Chlachidze, G.; Evbota, D.; Kashikhin, V.S.; Lamm, M.; Makarov, A.; Tartaglia, M.; Nakamoto, T.; Ogitsu, T.; Tanaka, K.; Yamamoto, A.; /KEK, Tsukuba

    2011-09-01

    A new generation of precision muon conversion experiments is planned at both Fermilab and KEK. These experiments will depend upon a complex set of solenoid magnets for the production, momentum selection and transport of a muon beam to a stopping target, and for tracking detector momentum analysis of candidate conversion electrons from the target. Baseline designs for the production and detector solenoids use NbTi cable that is heavily stabilized by an extruded high RRR aluminum jacket. A U.S.-Japan research collaboration has begun whose goal is to advance the development of optimized Al-NbTi conductors, gain experience with the technology of winding coils from this material, and test the conductor performance as modest length samples become available. For this purpose, a 'conductor test' solenoid with three coils was designed and built at Fermilab. A sample of the RIKEN Al-NbTi conductor from KEK was wound into a 'test' coil; this was sandwiched between two 'field' coils wound from doubled SSC cable, to increase the peak field on the RIKEN test coil. All three solenoid coils were epoxy impregnated, and utilized aluminum outer bandage rings to apply preload to the coils when cold. The design and fabrication details, and results of the magnet quench performance tests are presented and discussed.

  1. Instability of Hydrogenated TiO2

    SciTech Connect (OSTI)

    Nandasiri, Manjula I.; Shutthanandan, V.; Manandhar, Sandeep; Schwarz, Ashleigh M.; Oxenford, Lucas S.; Kennedy, John V.; Thevuthasan, Suntharampillai; Henderson, Michael A.

    2015-11-06

    Hydrogenated TiO2 (H-TiO2) is toted as a viable visible light photocatalyst. We report a systematic study on the thermal stability of H-implanted TiO2 using X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), Rutherford backscattering spectrometry (RBS) and nuclear reaction analysis (NRA). Protons (40 keV) implanted at a ~2 atom % level within a ~120 nm wide profile of rutile TiO2(110) were situated ~300 nm below the surface. NRA revealed that this H-profile broadened preferentially toward the surface after annealing at 373 K, dissipated out of the crystal into vacuum at 473 K, and was absent within the beam sampling depth (~800 nm) at 523 K. Photoemission showed that the surface was reduced in concert with these changes. Similar anneals had no effect on pristine TiO2(110). The facile bulk diffusivity of H in rutile, as well as its activity toward interfacial reduction, significantly limits the utilization of H-TiO2 as a photocatalyst. This work was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences & Biosciences. Pacific Northwest National Laboratory (PNNL) is a multiprogram national laboratory operated for DOE by Battelle. The research was performed using the Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory.

  2. 2012 ALS User Meeting Awards

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2 ALS User Meeting Awards Recipients of the 2012 Users' Executive Committee awards and Student Poster Competition were announced Tuesday, October 9, at the ALS User Meeting. David A. Shirley Award for Outstanding Scientific Achievement at the ALS shirley award The David A. Shirley Award for Scientific Achievement went to, from left, Carl Percival (University of Manchester), Dudley Shallcross [(University of Bristol) not pictured], and Craig Taatjes and David Osborn (Sandia), for making the first

  3. ALS Doctoral Fellowship in Residence

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Doctoral Fellowship in Residence Print The Advanced Light Source (ALS), a division of Lawrence Berkeley National Laboratory, is a national user facility that generates intense x-ray radiation for scientific and technological research. As the world's first third-generation synchrotron radiation source, the ALS offers outstanding performance in the VUV-soft x-ray energy range and excellent performance into the hard x-ray region. The facility welcomes researchers from universities, industries,

  4. ALS Doctoral Fellowship in Residence

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Doctoral Fellowship in Residence Print The Advanced Light Source (ALS), a division of Lawrence Berkeley National Laboratory, is a national user facility that generates intense x-ray radiation for scientific and technological research. As the world's first third-generation synchrotron radiation source, the ALS offers outstanding performance in the VUV-soft x-ray energy range and excellent performance into the hard x-ray region. The facility welcomes researchers from universities, industries,

  5. ALS Scientific Advisory Committee Charter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Scientific Advisory Committee Charter Print This document was revised and approved December 18, 2008. I. FUNCTION AND REPORTING The ALS Scientific Advisory Committee (SAC) is advisory to the Berkeley Lab Director through the ALS Director. The SAC serves two primary functions: It acts as a "board of directors" to advise the Laboratory on current and future ALS operations, allocation of facility resources, strategic planning, budget development, and other major issues; and It reviews

  6. ALS Scientific Advisory Committee Charter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Scientific Advisory Committee Charter Print This document was revised and approved December 18, 2008. I. FUNCTION AND REPORTING The ALS Scientific Advisory Committee (SAC) is advisory to the Berkeley Lab Director through the ALS Director. The SAC serves two primary functions: It acts as a "board of directors" to advise the Laboratory on current and future ALS operations, allocation of facility resources, strategic planning, budget development, and other major issues; and It reviews

  7. ALS Collaborative Postdoctoral Fellowship Program

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    the National Center of Electron Microscopy, and the National Energy Research Scientific Computing Center. ALS Collaborative Postdoctoral Fellowships normally provide only partial...

  8. AL2007-05.doc

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AL 2007-05 Acquisition Regulation Date 03292007 ACQUISITION LETTER This Acquisition ... LETTERS REMAINING IN EFFECT NUMBER DATE SUBJECT 93-4 040793 Displaced Workers ...

  9. Data Management at the ALS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Data Management at the ALS Print Users of the ALS are responsible for meeting their data management obligations to their home institutions and granting agencies. Except as noted below for data stored at NERSC, the ALS does not provide specific resources to manage data that are generated through user experiments. Because the ALS does not have a facility-wide data archiving service or staff to manage the data, the user must generally make arrangements to copy data to their own storage systems or

  10. ALS Collaborative Postdoctoral Fellowship Program

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    scientists) to discuss possible projects and to identify external sources of matching funds. Applicants must then submit a completed ALS Collaborative Postdoctoral...

  11. ALS Evidence Confirms Combustion Theory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Evidence Confirms Combustion Theory Print Researchers recently uncovered the first step in the process that transforms gas-phase molecules into solid particles like soot and...

  12. ALS Scientific Advisory Committee Charter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    It acts as a "board of directors" to advise the Laboratory on current and future ALS operations, allocation of facility resources, strategic planning, budget development, and...

  13. Materials Data on TiAlFe2 (SG:225) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  14. Materials Data on Ti3AlC (SG:221) by Materials Project

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  15. Materials Data on Ti3AlN (SG:221) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2015-02-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  16. Materials Data on TiAl (SG:123) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  17. Materials Data on TiAl2 (SG:65) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2015-03-19

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  18. Materials Data on TiAlAu (SG:194) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2015-03-08

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  19. Multiple conducting carriers generated in LaAlO3/SrTiO3 heterostructur...

    Office of Scientific and Technical Information (OSTI)

    the origin of high-mobility transport to the low-density conducting carriers. Authors: Seo, Sung Seok A 1 ; Marton, Zsolt 1 ; Choi, W. S. 2 ; Hassink, G. W. J. 3 ; Blank, ...

  20. ALS Collaborative Postdoctoral Fellowship Program

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Collaborative Postdoctoral Fellowship Program Print The Advanced Light Source (ALS) Collaborative Postdoctoral Fellowship program provides challenging opportunities to conduct research and instrument development in areas supporting the scientific programs of the Department of Energy (DOE), Lawrence Berkeley National Laboratory (LBNL), and the ALS that include physical, chemical, material, energy, environmental, geological, and biological sciences. Fellows pursue individual research projects as

  1. ALS Collaborative Postdoctoral Fellowship Program

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Collaborative Postdoctoral Fellowship Program Print The Advanced Light Source (ALS) Collaborative Postdoctoral Fellowship program provides challenging opportunities to conduct research and instrument development in areas supporting the scientific programs of the Department of Energy (DOE), Lawrence Berkeley National Laboratory (LBNL), and the ALS that include physical, chemical, material, energy, environmental, geological, and biological sciences. Fellows pursue individual research projects as

  2. ALS Collaborative Postdoctoral Fellowship Program

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Collaborative Postdoctoral Fellowship Program Print The Advanced Light Source (ALS) Collaborative Postdoctoral Fellowship program provides challenging opportunities to conduct research and instrument development in areas supporting the scientific programs of the Department of Energy (DOE), Lawrence Berkeley National Laboratory (LBNL), and the ALS that include physical, chemical, material, energy, environmental, geological, and biological sciences. Fellows pursue individual research projects as

  3. Morphology, deformation, and defect structures of TiCr{sub 2} in Ti-Cr alloys

    SciTech Connect (OSTI)

    Chen, K.C.; Allen, S.M.; Livingston, J.D.

    1992-12-31

    The morphologies and defect structures of TiCr{sub 2} in several Ti-Cr alloys have been examined by optical metallography, x-ray diffraction, and transmission electron microscopy (TEM), in order to explore the room-temperature deformability of the Laves phase TiCr{sub 2}. The morphology of the Laves phase was found to be dependent upon alloy composition and annealing temperature. Samples deformed by compression have also been studied using TEM. Comparisons of microstructures before and after deformation suggest an increase in twin, stacking fault, and dislocation density within the Laves phase, indicating some but not extensive room-temperature deformability.

  4. Solution-Derived Bi(ZnTi)O3 - BaTiO3 Thin Films with Bulk-like...

    Office of Scientific and Technical Information (OSTI)

    Title: Solution-Derived Bi(ZnTi)O3 - BaTiO3 Thin Films with Bulk-like Permittivity. Abstract not provided. Authors: Meyer, Kelsey Elizabeth ; Kotula, Paul Gabriel ; Brennecka, ...

  5. Carrier-Controlled Ferromagnetism in SrTiO3

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Moetakef, Pouya; Williams, James R.; Ouellette, Daniel G.; Kajdos, Adam P.; Goldhaber-Gordon, David; Allen, S. James; Stemmer, Susanne

    2012-06-27

    Magnetotransport and superconducting properties are investigated for uniformly La-doped SrTiO3 films and GdTiO3/SrTiO3 heterostructures, respectively. GdTiO3/SrTiO3 interfaces exhibit a high-density 2D electron gas on the SrTiO3 side of the interface, while, for the SrTiO3 films, carriers are provided by the dopant atoms. Both types of samples exhibit ferromagnetism at low temperatures, as evidenced by a hysteresis in the magnetoresistance. For the uniformly doped SrTiO3 films, the Curie temperature is found to increase with doping and to coexist with superconductivity for carrier concentrations on the high-density side of the superconducting dome. The Curie temperature of the GdTiO3/SrTiO3 heterostructures scales with themore » thickness of the SrTiO3 quantum well. The results are used to construct a stability diagram for the ferromagnetic and superconducting phases of SrTiO3.« less

  6. Structure and physical properties of single crystal PrCr{sub 2}Al{sub 20} and CeM{sub 2}Al{sub 20} (M=V, Cr): A comparison of compounds adopting the CeCr{sub 2}Al{sub 20} structure type

    SciTech Connect (OSTI)

    Kangas, Michael J.; Schmitt, Devin C.; Sakai, Akito; Nakatsuji, Satoru; Institute of Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581 ; Chan, Julia Y.

    2012-12-15

    Crystal growth and full structure determination of compounds adopting the CeCr{sub 2}Al{sub 20} structure type, LnTi{sub 2}Al{sub 20} (Ln=La-Pr, Sm, and Yb), LnV{sub 2}Al{sub 20} (Ln=La-Pr, and Sm), and LnCr{sub 2}Al{sub 20} (Ln=La-Pr, Sm, and Yb), are reported. Resistivity, magnetic susceptibility, and heat capacity of flux grown single crystals of the nonmagnetic CeM{sub 2}Al{sub 20} (Ln=Ce, Yb; M=Ti, V) compounds are compared to PrCr{sub 2}Al{sub 20}. Of particular interest is PrCr{sub 2}Al{sub 20} which does not show any phase transition down to the lowest temperature of the measurement (400 mK in resistivity measurement and 1.8 K for magnetic susceptibility measurements) and exhibits Kondo behavior at low temperatures. - Graphical abstract: Crystal structure of SmV{sub 2}Al{sub 20} showing the interpenetrating diamond-like samarium network and pyrochlore-like vanadium network. Highlights: Black-Right-Pointing-Pointer Single crystals of LnM{sub 2}Al{sub 20} were grown from a molten aluminum flux. Black-Right-Pointing-Pointer Magnetic, electrical, and specific heat of single crystal LnM{sub 2}Al{sub 20} are presented. Black-Right-Pointing-Pointer PrCr{sub 2}Al{sub 20} exhibits evidence of Kondo effect.

  7. Giant persistent photoconductivity in BaTiO{sub 3}/TiO{sub 2} heterostructures

    SciTech Connect (OSTI)

    Plodinec, Milivoj; anti?, Ana; Gajovi?, Andreja; Zavanik, Janez; ?eh, Miran

    2014-10-13

    The persistent photoconductivity (PPC) effect in nanotube arrays of barium titanate and TiO{sub 2} (BTO/TiO{sub 2}NT) was studied at room temperature under daylight illumination. The BTO/TiO{sub 2}NT heterostructures exhibited a giant PPC effect that was six orders of magnitude higher than the dark conductivity, followed by a slow relaxation for 3 h. The PPC in this material was explained by the existence of defects at the surfaces and the interfaces of the investigated heterostructures. The sample was prepared using a two-step synthesis: the anodization of a Ti-foil and a subsequent hydrothermal synthesis. The structural and electrical characteristics were studied by micro-Raman spectroscopy, field-emission-gun scanning electron microscopy, and impedance spectroscopy.

  8. Development of ODS FeCrAl alloys for accident-tolerant fuel cladding

    SciTech Connect (OSTI)

    Dryepondt, Sebastien N.; Hoelzer, David T.; Pint, Bruce A.; Unocic, Kinga A.

    2015-09-18

    FeCrAl alloys are prime candidates for accident-tolerant fuel cladding due to their excellent oxidation resistance up to 1400 C and good mechanical properties at intermediate temperature. Former commercial oxide dispersion strengthened (ODS) FeCrAl alloys such as PM2000 exhibit significantly better tensile strength than wrought FeCrAl alloys, which would alloy for the fabrication of a very thin (~250 m) ODS FeCrAl cladding and limit the neutronic penalty from the replacement of Zr-based alloys by Fe-based alloys. Several Fe-12-Cr-5Al ODS alloys where therefore fabricated by ball milling FeCrAl powders with Y2O3 and additional oxides such as TiO2 or ZrO2. The new Fe-12Cr-5Al ODS alloys showed excellent tensile strength up to 800 C but limited ductility. Good oxidation resistance in steam at 1200 and 1400 C was observed except for one ODS FeCrAl alloy containing Ti. Rolling trials were conducted at 300, 600 C and 800 C to simulate the fabrication of thin tube cladding and a plate thickness of ~0.6mm was reached before the formation of multiple edge cracks. Hardness measurements at different stages of the rolling process, before and after annealing for 1h at 1000 C, showed that a thinner plate thickness could likely be achieved by using a multi-step approach combining warm rolling and high temperature annealing. Finally, new Fe-10-12Cr-5.5-6Al-Z gas atomized powders have been purchased to fabricate the second generation of low-Cr ODS FeCrAl alloys. The main goals are to assess the effect of O, C, N and Zr contents on the ODS FeCrAl microstructure and mechanical properties, and to optimize the fabrication process to improve the ductility of the 2nd gen ODS FeCrAl while maintaining good mechanical strength and oxidation resistance.

  9. A=18C (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of the 48Ca(18O, 18C)48Ti reaction. 18C is then bound by 4.188 MeV with respect to breakup into 17C + n. See also (1982FI10, 1987AJ02, 1992WA22). 1. 18C(-)18N Qm 11.807 The...

  10. A=18Na (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    95TI07) (Not observed) 18Na has not been observed; its atomic mass excess has been estimated to be 25.32 MeV (1993AU05); it is then unbound with respect to proton emission by 1.6 MeV: see (1978AJ03). See also (1986AN07) and (1983ANZQ

  11. A=5Be (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (See the Isobar Diagram for 5Be) See also the A = 5 introductory discussion titled A = 5 resonance parameters. The absence of any group structure in the neutron spectrum in the reaction 3He(3He, n)5Be at E(3He) = 18.0 to 26.0 MeV indicates that 5Beg.s

  12. ALS Doctoral Fellowship in Residence

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and technological research. As the world's first third-generation synchrotron radiation source, the ALS offers outstanding performance in the VUV-soft x-ray energy range and...

  13. ALS 20th Anniversary Celebration

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    20th Anniversary Celebration Print The 20th anniversary of the ALS was celebrated on Friday, October 4, with style, good humor, lots of stories, and a very large cake. More...

  14. ALS Scientific Advisory Committee Charter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ... The SAC will meet as often as necessary but no less than twice a year. The deliberations of the SAC will be confidential to the extent legally possible. The ALS Director andor ...

  15. Epitaxial growth of NiTiO3 with a distorted ilmenite structure

    SciTech Connect (OSTI)

    Varga, Tamas; Droubay, Timothy C.; Bowden, Mark E.; Nachimuthu, Ponnusamy; Shutthanandan, V.; Bolin, Trudy B.; Shelton, William A.; Chambers, Scott A.

    2012-06-30

    MTiO3 (M = Fe, Mn, Ni) compounds have received recent attention as possible candidates for new multiferroic materials capable of magnetization switching by application of an electric field. Epitaxial Ni1-xTi1-yO3 films of different thickness and composition were deposited on Al2O3(0001) by pulsed laser deposition, and characterized using several techniques. Structural parameters for the metastable LiNbO3-type NiTiO3 structure with the space group R3c were predicted using density functional theory calculations, and compared with the experimental results. Our structural data from x-ray diffraction and x-ray absorption spectroscopy indicate that epitaxial ilmenite-type NiTiO3 films were successfully grown. Furthermore, lattice strain exerted by the sapphire substrate results in a distorted ilmenite structure similar to the LiNbO3-type one. Our results demonstrate the potential of oxide heteroepitaxy to stabilize metastable multiferroic phases that may be difficult to prepare or are inaccessible in the bulk.

  16. Influence of fatigue on the nanohardness of NiTiCr-wires

    SciTech Connect (OSTI)

    Frotscher, M.; Young, M. L.; Bei, Hongbin; George, Easo P; Neuking, K.; Eggeler, G.

    2009-01-01

    Testing parameters, such as rotational speed and bending radius, have a strong influence on the fatigue life of pseudoelastic NiTi shape-memory alloys during bending rotation fatigue (BRF) experiments [M. F. X. Wagner, Int. J. Mat. Res. 97 (2006), p. 1687-1696. and M. Frotscher, et al., Thermomechanical processing, microstructure and bending rotation fatigue of ultra-fine grained NiTiCr-wires, Proceedings of the International Conference for Shape Memory and Superelastic Technologies (SMST 2007), Tsukuba, Japan, ASM International, (2008), p. 149-158.]. Previous studies showed a decrease in the fatigue life for smaller bending radius (i.e. higher equivalent strain) and larger rotational speed. This observation is associated with an increase of dislocation density, the stabilization of stressinduced martensite during cycling, and an increase of the plateau stresses due to self-heating. In the present study, we examine the influence of these fatigue parameters on the nanohardness and shape recovery of pseudoelastic NiTiCr shape-memory alloy wires by nanoindentation. We show that nanoindentation is a suitable method for the characterization of fatigue-related microstructural changes, which affect the mechanical properties.

  17. ALS Doctoral Fellowship in Residence

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Doctoral Fellowship in Residence Print The Advanced Light Source (ALS), a division of Lawrence Berkeley National Laboratory, is a national user facility that generates intense x-ray radiation for scientific and technological research. As the world's first third-generation synchrotron radiation source, the ALS offers outstanding performance in the VUV-soft x-ray energy range and excellent performance into the hard x-ray region. The facility welcomes researchers from universities, industries, and

  18. ALS Doctoral Fellowship in Residence

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Doctoral Fellowship in Residence Print The Advanced Light Source (ALS), a division of Lawrence Berkeley National Laboratory, is a national user facility that generates intense x-ray radiation for scientific and technological research. As the world's first third-generation synchrotron radiation source, the ALS offers outstanding performance in the VUV-soft x-ray energy range and excellent performance into the hard x-ray region. The facility welcomes researchers from universities, industries, and

  19. ALS Doctoral Fellowship in Residence

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Doctoral Fellowship in Residence Print The Advanced Light Source (ALS), a division of Lawrence Berkeley National Laboratory, is a national user facility that generates intense x-ray radiation for scientific and technological research. As the world's first third-generation synchrotron radiation source, the ALS offers outstanding performance in the VUV-soft x-ray energy range and excellent performance into the hard x-ray region. The facility welcomes researchers from universities, industries, and

  20. ALS Evidence Confirms Combustion Theory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Evidence Confirms Combustion Theory ALS Evidence Confirms Combustion Theory Print Wednesday, 22 October 2014 11:43 Researchers recently uncovered the first step in the process that transforms gas-phase molecules into solid particles like soot and other carbon-based compounds. It's a discovery that could help combustion chemists make more efficient, less polluting fuels and help materials scientists fine-tune their carbon nanotubes and graphene sheets for faster, smaller electronics. In

  1. The corrosivity and passivity of sputtered Mg-Ti alloys

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Song, Guang -Ling; Unocic, Kinga A.; Meyer, III, Harry M.; Cakmak, Ercan; Brady, Michael P.; Gannon, Paul E.; Himmer, Phil; Andrews, Quinn

    2015-11-30

    Our study explored the possibility of forming a “stainless” Mg–Ti alloy. The electrochemical behavior of magnetron-sputtered Mg–Ti alloys was measured in a NaCl solution, and the surface films on the alloys were examined by XPS, SEM and TEM. Increased corrosion resistance was observed with increased Ti content in the sputtered Mg–Ti alloys, but passive-like behavior was not reached until the Ti level (atomic %) was higher than the Mg level. Moreover, the surface film that formed on sputtered Mg–Ti based alloys in NaCl solution was thick, discontinuous and non-protective, whereas a thin, continuous and protective Mg and Ti oxide filmmore » was formed on a sputtered Ti–Mg based alloy.« less

  2. The corrosivity and passivity of sputtered Mg-Ti alloys

    SciTech Connect (OSTI)

    Song, Guang -Ling; Unocic, Kinga A.; Meyer, III, Harry M.; Cakmak, Ercan; Brady, Michael P.; Gannon, Paul E.; Himmer, Phil; Andrews, Quinn

    2015-11-30

    Our study explored the possibility of forming a “stainless” Mg–Ti alloy. The electrochemical behavior of magnetron-sputtered Mg–Ti alloys was measured in a NaCl solution, and the surface films on the alloys were examined by XPS, SEM and TEM. Increased corrosion resistance was observed with increased Ti content in the sputtered Mg–Ti alloys, but passive-like behavior was not reached until the Ti level (atomic %) was higher than the Mg level. Moreover, the surface film that formed on sputtered Mg–Ti based alloys in NaCl solution was thick, discontinuous and non-protective, whereas a thin, continuous and protective Mg and Ti oxide film was formed on a sputtered Ti–Mg based alloy.

  3. Experimental investigations of material models for Ti-6A1-4V and 2024-T3

    SciTech Connect (OSTI)

    Leseur, D

    1999-05-03

    This report describes studies of the deformation and failure behavior of Ti-6Al-4V and 2024-T3 aluminum. Data was obtained at high strain rates and large strains using the split Hopkinson pressure bar technique. This information, plus additional data from the literature, was used to critically evaluate the ability of the Johnson Cook material model to represent the deformation and failure response of Ti-6AMV and 2024-T3 under conditions relevant to simulations of engine containment and the influence of uncontained engine debris on aircraft structures. This model is being used in the DYNA3D finite element code, which is being developed/validated for evaluating aircraft/engine designs relative to the federal airworthiness standards and for improving mitigation/containment technology. The results of the experimental work reported here were used to define a new set of material constants for the strength component of the Johnson Cook model for Ti-6Al-4V and 2024-T3. The capabilities and limitations of the model are reviewed. The model can accurately represent the stress-strain response of the materials. The major concern with the Johnson Cook material model is its ability to accurately represent the stress - strain rate response at strain rates greater than 10{sup 3}-10{sup 4} s{sup {minus}1}. Additional work is also needed to adequately account for failure via shear localization, which was the dominant failure mode at high strain rates in both materials. Failure modeling in both Ti-6Al-N and 2024-T3 will be considered further in future reports.

  4. Role of Y-Al oxides during extended recovery process of a ferritic ODS alloy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Capdevila, C.; Pimentel, G.; Aranda, M. M.; Rementeria, R.; Dawson, K.; Urones-Garrote, E.; Tatlock, G. J.; Miller, Michael K.

    2015-08-04

    The microstructural stability of Y-Al oxides during the recrystallization of Fe-Cr-Al oxide dispersion strengthened alloy is studied in this work. The goal is to determine the specific distribution pattern of oxides depending where they are located: in the matrix or at the grain boundaries. It was concluded that those located at the grain boundaries yielded a faster coarsening than the ones in the matrix, although no significant differences in composition and/or crystal structure were observed. However, the recrystallization heat treatment leads to the dissolution of the Y2O3 and its combination with Al to form the YAlO3 perovskite oxide particles process,more » mainly located at the grain boundaries. Lastly, atom probe tomography analysis revealed a significant Ti build-up at the grain boundaries that might affect subsequent migration during recrystallization.« less

  5. Role of Y-Al oxides during extended recovery process of a ferritic ODS alloy

    SciTech Connect (OSTI)

    Capdevila, C.; Pimentel, G.; Aranda, M. M.; Rementeria, R.; Dawson, K.; Urones-Garrote, E.; Tatlock, G. J.; Miller, Michael K.

    2015-08-04

    The microstructural stability of Y-Al oxides during the recrystallization of Fe-Cr-Al oxide dispersion strengthened alloy is studied in this work. The goal is to determine the specific distribution pattern of oxides depending where they are located: in the matrix or at the grain boundaries. It was concluded that those located at the grain boundaries yielded a faster coarsening than the ones in the matrix, although no significant differences in composition and/or crystal structure were observed. However, the recrystallization heat treatment leads to the dissolution of the Y2O3 and its combination with Al to form the YAlO3 perovskite oxide particles process, mainly located at the grain boundaries. Lastly, atom probe tomography analysis revealed a significant Ti build-up at the grain boundaries that might affect subsequent migration during recrystallization.

  6. Sheet resistance under Ohmic contacts to AlGaN/GaN heterostructures

    SciTech Connect (OSTI)

    Hajłasz, M.; Donkers, J. J. T. M.; Sque, S. J.; Heil, S. B. S.; Gravesteijn, D. J.; Rietveld, F. J. R.; Schmitz, J.

    2014-06-16

    For the determination of specific contact resistance in semiconductor devices, it is usually assumed that the sheet resistance under the contact is identical to that between the contacts. This generally does not hold for contacts to AlGaN/GaN structures, where an effective doping under the contact is thought to come from reactions between the contact metals and the AlGaN/GaN. As a consequence, conventional extraction of the specific contact resistance and transfer length leads to erroneous results. In this Letter, the sheet resistance under gold-free Ti/Al-based Ohmic contacts to AlGaN/GaN heterostructures on Si substrates has been investigated by means of electrical measurements, transmission electron microscopy, and technology computer-aided design simulations. It was found to be significantly lower than that outside of the contact area; temperature-dependent electrical characterization showed that it exhibits semiconductor-like behavior. The increase in conduction is attributed to n-type activity of nitrogen vacancies in the AlGaN. They are thought to form during rapid thermal annealing of the metal stack when Ti extracts nitrogen from the underlying semiconductor. The high n-type doping in the region between the metal and the 2-dimensional electron gas pulls the conduction band towards the Fermi level and enhances horizontal electron transport in the AlGaN. Using this improved understanding of the properties of the material underneath the contact, accurate values of transfer length and specific contact resistance have been extracted.

  7. Bioactive glass coatings with hydroxyapatite and Bioglass (registered) particles on Ti-based implants. 1. Processing

    SciTech Connect (OSTI)

    Gomez-Vega, J.M.; Saiz, E.; Tomsia, A.P.; Marshall, G.W.; Marshall, S.J.

    1999-06-01

    Silicate-based glasses with thermal expansion coefficients that match those of Ti6Al4V were prepared and used to coat Ti6Al4V by a simple enameling technique. Bioglass (BG) (registered) or hydroxyapatite (HA) particles were embedded on the coatings in order to enhance their bioactivity. HA particles were partially embedded during heating and remained firmly embedded on the coating after cooling. There was no apparent reaction at the glass/HA interface at the temperatures used in this work (800-840 degrees C). In contrast, BG particles softened and some infiltration into the glass coating took place during heat treatment. In this case, particles with sizes over 45 (mu)m were required, otherwise the particles became hollow due to the infiltration and crystallization of the glass surface. The concentration of the particles on the coating was limited to 20% of surface coverage. Concentrations above this value resulted in cracked coatings due to excessive induced stress. Cracks did not prop agate along the interfaces when coatings were subjected to Vickers indentation tests, indicating that the particle/glass and glass/metal interfaces exhibited strong bonds. Enameling, producing excellent glass/metal adhesion with well-attached bioactive particles on the surface, is a promising method of forming reliable and lasting implants which can endure substantial chemical and mechanical stresses.

  8. Influence of Ni on Martensitic Phase Transformations in NiTi Shape Memory Alloys

    SciTech Connect (OSTI)

    Frenzel, J.; George, Easo P; Dlouhy, A.; Somsen, Ch.; Wagner, M. F.-X; Eggeler, G.

    2010-01-01

    High-precision data on phase transformation temperatures in NiTi, including numerical expressions for the effect of Ni on M{sub S}, M{sub F}, A{sub S}, A{sub F} and T{sub 0}, are obtained, and the reasons for the large experimental scatter observed in previous studies are discussed. Clear experimental evidence is provided confirming the predictions of Tang et al. 1999 regarding deviations from a linear relation between the thermodynamic equilibrium temperature and Ni concentration. In addition to affecting the phase transition temperatures, increasing Ni contents are found to decrease the width of thermal hysteresis and the heat of transformation. These findings are rationalized on the basis of the crystallographic data of Prokoshkin et al. 2004 and the theory of Ball and James. The results show that it is important to document carefully the details of the arc-melting procedure used to make shape memory alloys and that, if the effects of processing are properly accounted for, precise values for the Ni concentration of the NiTi matrix can be obtained.

  9. Structural and Morphological Difference Between Ti/TiN/TiCN Coatings Grown in Multilayer and Graded Form

    SciTech Connect (OSTI)

    Restrepo, E.; Baena, A.; Agudelo, C.; Castillo, H.; Devia, A.; Marino, A.

    2006-12-04

    Thin films can be grown in super-lattice, multilayers and graded form, having each one advantages and disadvantages. The difference between multilayer and graded coatings is the interface. In multilayers the interface is abrupt and in graded coatings it is diffuse. The interface influences many chemical and physical properties of the materials, and its choice depends on the application. Graded coatings have the advantage of having gradual properties such as thermal expansion coefficient and lattice parameter, avoiding adherence problems due to good match between their component materials. In this work the comparison between some properties of coatings grown as multilayer and graded is performed. The materials are produced using the sputtering DC technique because of its facility to control the deposition parameters and generate a slow growth. The target is a disc of titanium and the samples are made of stainless steel 304. The working gases are argon, nitrogen and methane, which are mixed according to the material to be produced, i.e. Ti layer is grown with argon, the TiN film is produced with a mixture of argon and nitrogen, and the TiCN material is obtained mixing argon, nitrogen and methane. These materials are characterized with AFM in order to determine grain size and with XPS studying the chemical composition and performing depth profiles.

  10. Microsoft Word - AL2006-11.doc

    Broader source: Energy.gov (indexed) [DOE]

    Guide Chapter 7.1, Acquisition Planning Acquisition Guide Chapter 42.5, Contract Management Planning When is this Acquisition Letter (AL) Effective? This AL is effective...

  11. ALS Ceramics Materials Research Advances Engine Performance

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Ceramics Materials Research Advances Engine Performance ALS Ceramics Materials Research Advances Engine Performance Print Thursday, 27 September 2012 00:00 ritchie ceramics...

  12. ALS@20 Kick-Off Celebration

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    tribulations encountered during the construction of the ALS from former Director Jay Marx, current ALS Scientific Director Steve Kevan and Director Roger Falcone talked about...

  13. ALS 20th Anniversary Celebration

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    20th Anniversary Celebration Print The 20th anniversary of the ALS was celebrated on Friday, October 4, with style, good humor, lots of stories, and a very large cake. More important, however, was the large number of current and former colleagues and users, who were delighted to have the opportunity to visit and catch up with former workmates. When not chatting with colleagues or listening to the high-shool chamber trio, attendees were entertained by a video montage, old photos featuring ALS

  14. A=3n (1987TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1987TI07) (Not illustrated) GENERAL: The weight of experimental evidence reviewed in the previous compilation of Fiarman and Hanna (1975FI08) is strongly against the existence of a bound state of the three-neutron system, and only controversial evidence of 3n resonances was cited. Several experiments carried out more recently have strengthened the evidence against the bound trineutron and have failed to discover resonance structure that cannot be otherwise explained. The most suggestive work is

  15. A Review Corrosion of TI Grade 7 and Other TI Alloys in Nuclear Waste Repository Environments

    SciTech Connect (OSTI)

    F. Hua; K. Mon; P. Pasupathi; G. Gordon

    2004-05-11

    Titanium alloy degradation modes are reviewed in relation to their performance in repository environments. General corrosion, localized corrosion, stress corrosion cracking, hydrogen induced cracking, microbially influenced corrosion, and radiation-assisted corrosion of Ti alloys are considered. With respect to the Ti Grade 7 drip shields selected for emplacement in the repository at Yucca Mountain, general corrosion, hydrogen induced cracking, and radiation-assisted corrosion will not lead to failure within the 10,000 year regulatory period; stress corrosion cracking (in the absence of disruptive events) is of no consequence to barrier performance; and localized corrosion and microbially influenced corrosion are not expected to occur. To facilitate the discussion, Ti Grades 2, 5, 7, 9, 11, 12, 16, 17, 18, and 24 are included in this review.

  16. Nature of Transactions (TI) Code | National Nuclear Security Administration

    National Nuclear Security Administration (NNSA)

    | (NNSA) Nature of Transactions (TI) Code U.S. Department of Energy / U.S. Nuclear Regulatory Commission Nuclear Materials Management & Safeguards System Nature of Transactions (TI) Code* Nature of Transactions (TI) Code* Code: Description: A Initiates lease and financial responsibility of DOE-owned material B Transfer of lease and financial responsiblity of DOE-owned material C Transfer of DOE-owned material with no change in lease or financial responsibility D Return to DOE for credit

  17. On the possibility of neutron generation in an imploding TiD{sub 2} puff Z pinch

    SciTech Connect (OSTI)

    Baksht, Rina B.; Tel-Aviv University, Tel Aviv ; Oreshkin, Vladimir I.; Tomsk Polytechnic University, Tomsk ; Rousskikh, Alexander G.

    2013-08-15

    Simulation of implosion of a TiD{sub 2} puff Z pinch is reported. The Z pinch is supposed to be produced by the plasma flow generated by a vacuum arc, as described by Rousskikh et al.[Phys. Plasmas 18, 092707 (2011)]. To simulate the implosion, a one-dimensional two-temperature radiative magnetohydrodynamics code was used. The simulation has shown that neutrons are generated during the implosion of a TiD{sub 2} puff Z pinch due to thermalization of the pinch plasma stagnated on axis. It has been shown that the necessary condition for neutron generation is that the ion temperature must be substantially higher than the electron temperature. For a pinch current of 1 MA, the predicted yield of 'thermal' neutrons is 2.5 10{sup 9} neutrons/shot.

  18. Thermoelastic Analysis of a Vibrating TiB/Ti Cantilever Beam Using Differential Thermography

    SciTech Connect (OSTI)

    Byrd, Larry; Wyen, Travis; Byrd, Alex

    2008-02-15

    Differential thermography has been used to detect the fluctuating temperatures due the thermoelastic effect for a number of years. This paper examines functionally graded TiB/Ti cantilever beams excited on an electromechanical shaker in fully reversed bending. Finite difference analysis of specimens was used to look at the effect of heat conduction, convection and the fundamental frequency on the surface temperature distribution and compared to experimental data. The thermoelastic effect was also used to detect cracking and the stress field at the tip of the fixture during fatigue.

  19. Ab initio Study of He Stability in hcp-Ti

    SciTech Connect (OSTI)

    Dai, Yunya; Yang, Li; Peng, SM; Long, XG; Gao, Fei; Zu, Xiaotao T.

    2010-12-20

    The stability of He in hcp-Ti was studied using ab initio method based on density functional theory. The results indicate that a single He atom prefers to occupy the tetrahedral site rather than the octahedral site. The interaction of He defects with Ti atoms has been used to explain the relative stabilities of He point defects in hcp-Ti. The relative stability of He defects in hcp-Ti is useful for He clustering and bubble nucleation in metal tritides, which provides the basis for development of improved atomistic models.

  20. Strain-dependence Of The Structure And Ferroic Properties Of Epitaxial Ni-1 (-) Ti-x(1) (-) O-y(3) Thin Films Grown On Sapphire Substrates

    SciTech Connect (OSTI)

    Varga, Tamas; Droubay, Timothy C.; Bowden, Mark E.; Stephens, Sean A.; Manandhar, Sandeep; Shutthanandan, V.; Colby, Robert J.; Hu, Dehong; Shelton, William A.; Chambers, Scott A.

    2015-03-01

    Polarization-induced weak ferromagnetism has been predicted a few years back in perovskite MTiO3 (M = Fe, Mn, Ni) [Fennie, Phys. Rev. Lett. 100, 167203 (2008)]. We set out to stabilize this metastable perovskite structure by growing NiTiO3 epitaxially on sapphire Al2O3 (001) substrate, and to control the polar and magnetic properties via strain. Epitaxial Ni1-xTi1-yO3 films of different Ni/Ti ratios and thicknesses were deposited on Al2O3 substrates by pulsed laser deposition at different temperatures, and characterized using several techniques. The effect of film thickness, deposition temperature, and film stoichiometry on lattice strain, film structure, and physical properties was investigated. Our structural data from x-ray diffraction, electron microscopy, and x-ray absorption spectroscopy shows that substrate-induced strain has a marked effect on the structure and crystalline quality of the films. Physical property measurements reveal a dependence of the Nel transition and lattice polarization on strain, and highlight our ability to control the ferroic properties in NiTiO3 thin films by film stoichiometry and thickness.

  1. Cathodic cage plasma deposition of TiN and TiO{sub 2} thin films on silicon substrates

    SciTech Connect (OSTI)

    Sousa, Romulo R. M. de; Sato, Patricia S.; Nascente, Pedro A. P.; Viana, Bartolomeu C.; Alves, Clodomiro; Nishimoto, Akio

    2015-07-15

    Cathodic cage plasma deposition (CCPD) was used for growing titanium nitride (TiN) and titanium dioxide (TiO{sub 2}) thin films on silicon substrates. The main advantages of the CCPD technique are the uniformity, tridimensionality, and high rate of the film deposition that occurs at higher pressures, lower temperatures, and lower treatment times than those used in conventional nitriding treatments. In this work, the influence of the temperature and gas atmosphere upon the characteristics of the deposited films was investigated. The TiN and TiO{sub 2} thin films were characterized by x-ray diffraction, scanning electron microscopy, and Raman spectroscopy to analyze their chemical, structural, and morphological characteristics, and the combination of these results indicates that the low-cost CCPD technique can be used to produce even and highly crystalline TiN and TiO{sub 2} films.

  2. Ferroelectric Self-assembled PbTiO3 Perovskite Nanostructures...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Perovskite Nanostructures onto (100)SrTiO3 Substrates from a Novel Microemulsion-aided Sol-Gel Preparation Figure 1. PbTiO3 nanostructures onto (100) SrTiO3 substrates....

  3. Optimizing optical absorption of TiO{sub 2} by alloying with...

    Office of Scientific and Technical Information (OSTI)

    Title: Optimizing optical absorption of TiOsub 2 by alloying with TiSsub 2 TiOsub 2 is an attractive material for photocatalytic water splitting, but its band gap is too ...

  4. Dissociation of misfit and threading dislocations in Ba{sub 0.75}Sr{sub 0.25}TiO{sub 3} epitaxial film

    SciTech Connect (OSTI)

    Wang, Y.Q.; Liang, W.S.; Petrov, Peter Kr.; Alford, Neil McN.

    2011-03-15

    Ba{sub 0.75}Sr{sub 0.25}TiO{sub 3} film was epitaxially grown on a (001) LaAlO{sub 3} substrate using single-target pulsed laser deposition. The dissociation of misfit and threading dislocations in the epitaxial Ba{sub 0.75}Sr{sub 0.25}TiO{sub 3} film was investigated using high-resolution transmission electron microscopy (HRTEM). For a misfit dislocation with a Burgers vector of [200], it was shown that it could dissociate into four partial dislocations with Burgers vector of type 1/2 < 110>. For the threading dislocations, it was found that they usually coexist with stacking faults. The formation mechanism for the dissociated dislocations was discussed. All the dislocations can relieve the local strain in the Ba{sub 0.75}Sr{sub 0.25}TiO{sub 3} epitaxial film. - Research Highlights: {yields}Dissociation behaviour of misfit dislocations in Ba{sub 0.75}Sr{sub 0.25}TiO{sub 3} film. {yields}Dissociation behaviour of threading dislocations in Ba{sub 0.75}Sr{sub 0.25}TiO{sub 3} film. {yields}Formation mechanism of the dissociated dislocations.

  5. Microsoft Word - AL2008-05.doc

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy No. AL 2008-05 Acquisition Regulation Date 04/03/2008 ACQUISITION LETTER This Acquisition Letter is issued under the authority of the DOE and NNSA Procurement Executives. Subject: Environmental, Energy, and Transportation Management References: Executive Order 13423, dated January 24, 2007 Implementing Instructions, dated March 28, 2007 When is this Acquisition Letter (AL) effective? This AL is effective upon issuance. When does this AL Expire? This AL remains in effect

  6. Structure-Curie temperature relationships in BaTiO 3 -based ferroelect...

    Office of Scientific and Technical Information (OSTI)

    ferroelectric perovskites: Anomalous behavior of ( Ba , Cd ) TiO 3 from DFT, ... ferroelectric perovskites: Anomalous behavior of ( Ba , Cd ) TiO 3 from DFT, ...

  7. Effects of hydrochloric acid treatment of TiO{sub 2}nanoparticles...

    Office of Scientific and Technical Information (OSTI)

    Effects of hydrochloric acid treatment of TiOsub 2 nanoparticlesnanofibers bilayer film ... Title: Effects of hydrochloric acid treatment of TiOsub 2 nanoparticlesnanofibers ...

  8. Equation of State Model Quality Study for Ti and Ti64.

    SciTech Connect (OSTI)

    Wills, Ann Elisabet; Sanchez, Jason James

    2015-02-01

    Titanium and the titanium alloy Ti64 (6% aluminum, 4% vanadium and the balance ti- tanium) are materials used in many technologically important applications. To be able to computationally investigate and design these applications, accurate Equations of State (EOS) are needed and in many cases also additional constitutive relations. This report describes what data is available for constructing EOS for these two materials, and also describes some references giving data for stress-strain constitutive models. We also give some suggestions for projects to achieve improved EOS and constitutive models. In an appendix, we present a study of the 'cloud formation' issue observed in the ALEGRA code. This issue was one of the motivating factors for this literature search of available data for constructing improved EOS for Ti and Ti64. However, the study shows that the cloud formation issue is only marginally connected to the quality of the EOS, and, in fact, is a physical behavior of the system in question. We give some suggestions for settings in, and improvements of, the ALEGRA code to address this computational di culty.

  9. ALS Evidence Confirms Combustion Theory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Evidence Confirms Combustion Theory Print Researchers recently uncovered the first step in the process that transforms gas-phase molecules into solid particles like soot and other carbon-based compounds. It's a discovery that could help combustion chemists make more efficient, less polluting fuels and help materials scientists fine-tune their carbon nanotubes and graphene sheets for faster, smaller electronics. In addition, the results could have implications for the burgeoning field of

  10. ALS Evidence Confirms Combustion Theory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Evidence Confirms Combustion Theory Print Researchers recently uncovered the first step in the process that transforms gas-phase molecules into solid particles like soot and other carbon-based compounds. It's a discovery that could help combustion chemists make more efficient, less polluting fuels and help materials scientists fine-tune their carbon nanotubes and graphene sheets for faster, smaller electronics. In addition, the results could have implications for the burgeoning field of

  11. ALS Evidence Confirms Combustion Theory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Evidence Confirms Combustion Theory Print Researchers recently uncovered the first step in the process that transforms gas-phase molecules into solid particles like soot and other carbon-based compounds. It's a discovery that could help combustion chemists make more efficient, less polluting fuels and help materials scientists fine-tune their carbon nanotubes and graphene sheets for faster, smaller electronics. In addition, the results could have implications for the burgeoning field of

  12. ALS Evidence Confirms Combustion Theory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Evidence Confirms Combustion Theory Print Researchers recently uncovered the first step in the process that transforms gas-phase molecules into solid particles like soot and other carbon-based compounds. It's a discovery that could help combustion chemists make more efficient, less polluting fuels and help materials scientists fine-tune their carbon nanotubes and graphene sheets for faster, smaller electronics. In addition, the results could have implications for the burgeoning field of

  13. ALS Evidence Confirms Combustion Theory

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Evidence Confirms Combustion Theory Print Researchers recently uncovered the first step in the process that transforms gas-phase molecules into solid particles like soot and other carbon-based compounds. It's a discovery that could help combustion chemists make more efficient, less polluting fuels and help materials scientists fine-tune their carbon nanotubes and graphene sheets for faster, smaller electronics. In addition, the results could have implications for the burgeoning field of

  14. Crystal Structure and Thermodynamic Stability of Ba/Ti-Substituted Pollucites for Radioactive Cs/Ba Immobilization

    SciTech Connect (OSTI)

    Xu, Hongwu; Chavez, Manuel E.; Mitchell, Jeremy N.; Garino, Terry J.; Schwarz, Haiqing L.; Rodriguez, Mark A.; Rademacher, David X.; Nenoff, Tina Maria

    2015-04-23

    An analogue of the mineral pollucite (CsAlSi2O6), CsTiSi2O6.5 has a potential host phase for radioactive Cs. However, as 137Cs and 135Cs transmute to 137Ba and 135Ba, respectively, through the beta decay, it is essential to study the structure and stability of this phase upon Cs → Ba substitution. In this work, two series of Ba/Ti-substituted samples, CsxBa(1-x)/2TiSi2O6.5 and CsxBa1-xTiSi2O7-0.5x, (x = 0.9 and 0.7), were synthesized by high-temperature crystallization from their respective precursors. Synchrotron X-ray diffraction and Rietveld analysis reveal that while CsxBa(1-x)/2TiSi2O6.5 samples are phase-pure, CsxBa1-xTiSi2O7-0.5x samples contain Cs3x/(2+x)Ba(1-x)/(2+x)TiSi2O6.5 pollucites (i.e., also two-Cs-to-one-Ba substitution) and a secondary phase, fresnoite (Ba2TiSi2O8). Thus, the CsxBa1-xTiSi2O7-0.5x series is energetically less favorable than CsxBa(1-x)/2TiSi2O6.5. To study the stability systematics of CsxBa(1-x)/2TiSi2O6.5 pollucites, high-temperature calorimetric experiments were performed at 973 K with or without the lead borate solvent. Enthalpies of formation from the constituent oxides (and elements) have thus been derived. Our results show that with increasing Ba/(Cs + Ba) ratio, the thermodynamic stability of these phases decreases with respect to their component oxides. Hence, from the energetic viewpoint, continued Cs → Ba transmutation tends to destabilize the parent silicotitanate pollucite structure. However, the Ba-substituted pollucite co-forms with fresnoite (which incorporates the excess Ba

  15. A=10B (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (See Energy Level Diagrams for 10B) GENERAL: References to articles on general properties of 10B published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 10B located on our website at: (www.tunl.duke.edu/nucldata/General_Tables/10b.shtml). See also Table Prev. Table 10.18 preview 10.18 [Table of Energy Levels] (in PDF or PS). μ = +1.80064475 ± 0.00000057 μN: see (1989RA17); Q = +84.72

  16. A=19B (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    95TI07) (Not illustrated) 19B has been observed in the bombardment of Be by 12 MeV/A 56Fe ions (1984MU27) and in the fragmentation of 44 MeV/A 40Ar (1988GU1A) and 55 MeV/A 48Ca (1991MU19). See also (1989DE52). The mass excess adopted by (1993AU05) is 59.360 ± 0.400 MeV. Shell model predictions for low-lying levels are discussed in (1992WA22). See also (1989PO1K, 1990LO11

  17. A=20C (1998TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    98TI06) (Not illustrated) 20C has been observed in heavy ion projectile fragmentation reactions (1987GI05, 1990MU06, 1991MU19) and in proton-induced target-fragmentation reactions (1987VI13, 1988MU08, 1993WOZZ). The atomic mass excess is 37.560 ± 0.200 MeV (1995AU04). It is then stable with respect to 19C + n and 18C + 2n by 3.3 and 3.5 MeV, respectively. β-delayed neutron emission has been observed (1987GI05, 1990MU06, 1991MU19). The half life and neutron emission probability have been

  18. A=20N (1998TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    98TI06) (Not illustrated) 20N is particle stable. Its atomic mass excess is 21.770 ± 0.050 MeV (1995AU04). It has been observed in heavy-ion transfer (1989OR03) and projectile fragmentation reactions (1987GI05, 1988DUZT, 1988MU08, 1990MU06, 1991OR01) and in target fragmentation reactions (1988WO09, 1991RE02, 1993WOZZ). See also the review (1988VI1D). Mass measurements were reported in (1987GI05, 1988WO09, 1989OR03, 1991OR01, 1993WOZZ). Nuclear matter rms radii have been derived from

  19. A=3He (1987TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1987TI07) GENERAL: Ground State: Jπ = 1/2+, μ = -2.127624 ± 0.0000011 nm, M - A = 14.93132 ± 0.00003 MeV. General properties of the ground state of the A = 3 system are under 3H above. The wave function is predominantly S-state (~ 90%) with S'-state (1 - 2%) and D-state (~ 9%) admixtures (1975FI08, 1980PA12, 1984CI05, 1984CI09). For 3He the measured magnetic moment is μ = -2.127624 ± 0.0000011 nm (1978LEZA, 1978NE12). Calculations which include both impulse and pion exchange contributions

  20. A=3Li (1987TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1987TI07) GENERAL: The previous compilation (1975FI08) listed a small number of references reporting on the four reactions discussed below. Only one of the experiments cited contained any evidence for a 3p resonance, and the discussion suggested that the observed enhancement in 3He(p, n) was more likely a final state interaction. In the work reported since (1975FI08) and listed below, only (1974POZN) contains any mention of the tri-proton, and no evidence for its existence was observed. 1. 2H(p,

  1. A=4HE (1992TI02)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    He (1992TI02) (See Energy Level Diagrams for 4He) GENERAL: Ground state:Due to non-central forces, the wave function for the Jπ = 0+ ground state of 4He can be a positive-parity mixture of three 1S0, six 3P0, and five 5D0 orthogonal states (1967BE74). Of course, the symmetric S-wave component is the dominant part of the wavefunction, with significant D-wave and almost negligible P-wave contributions. Since the D-state admixture can be inferred from measurements such as the tensor analyzing

  2. A=4Li (1992TI02)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Li (1992TI02) (See Energy Level Diagrams for 4Li) GENERAL: The stability of 8B against particle decay (1988AJ01), in particular against decay into 4He + 4Li, sets an upper limit of 1.7 MeV on the separation energy of 4Li into p + 3He (1952SH44). The instability of 4H against particle decay (see 4H, GENERAL section) makes the particle stability of 4Li very unlikely, since the Coulomb energy of 4Li is approximately 1.7 MeV larger than that of 4H (1963WE10), and the nuclear energies should be

  3. A=5H (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (Not illustrated) See also the A = 5 introductory discussion titled A = 5 resonance parameters. The previous review (1988AJ01) noted that the 9Be(11B, 15O) reaction at E(11B) = 52 - 76 MeV showed no evidence for the formation of 5H (1986BE35, 1987BO40). For the earlier work see (1984AJ01). See also (1987KO47, 1988SEZJ). In several experiments on π- absorption at rest there is some evidence for the formation of a very broad (8 ± 3 MeV) resonance in the 5H system with Er = 7.4 ± 0.7

  4. A=5He (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (See Energy Level Diagrams for 5He) GENERAL: References to articles on general properties of 5He published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 5He located on our website at (www.tunl.duke.edu/NuclData/General_Tables/5he.shtml). See also Table Prev. Table 5.1 preview 5.1 [Table of Energy Levels] (in PDF or PS). See also the A = 5 introductory discussion titled A = 5 resonance

  5. A=5Li (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (See Energy Level Diagrams for 5Li) GENERAL: References to articles on general properties of 5Li published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 5Li located on our website at (www.tunl.duke.edu/NuclData/General_Tables/5li.shtml). See also Table Prev. Table 5.3 preview 5.3 [Table of Energy Levels] (in PDF or PS). See also the A = 5 introductory discussion titled A = 5 resonance

  6. A=6Be (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (See Energy Level Diagrams for 6Be) GENERAL: References to articles on general properties of 6Be published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 6Be located on our website at (www.tunl.duke.edu/NuclData/General_Tables/6be.shtml). See also Table Prev. Table 6.14 preview 6.14 [Table of Energy Levels] (in PDF or PS). 1. (a) 3He(3He, γ)6Be Qm = 11.4884 (b) 3He(3He, p)5Li Qm = 11.17

  7. A=6He (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (See Energy Level Diagrams for 6He) GENERAL: References to articles on general properties of 6He published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 6He located on our website at (www.tunl.duke.edu/NuclData/General_Tables/6he.shtml). See also Table Prev. Table 6.1 preview 6.1 [Table of Energy Levels] (in PDF or PS). Ground State Properties: The interaction radius of 6He, obtained

  8. A=6Li (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (See Energy Level Diagrams for 6Li) GENERAL: References to articles on general properties of 6He published since the previous review (1988AJ01) are grouped into categories and isted, along with brief descriptions of each item, in the General Tables for 6Li located on our website at (www.tunl.duke.edu/NuclData/General_Tables/6li.shtml). See also Table Prev. Table 6.4 preview 6.4 [Table of Energy Levels] (in PDF or PS). Ground State Properties: μ = +0.8220473(6) nm, +0.8220567(3) nm:

  9. A=7Be (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (See Energy Level Diagrams for 7Be) GENERAL: References to articles on general properties of 7Be published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 7Be located on our website at (www.tunl.duke.edu/NuclData/General_Tables/7be.shtml). See also Table Prev. Table 7.7 preview 7.7 [Table of Energy Levels] (in PDF or PS). The interaction nuclear radius of 7Be is 2.22 ± 0.02 fm

  10. A=7He (2002TI10)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2002TI10) (See Energy Level Diagrams for 7He) GENERAL: References to articles on general properties of 7He published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 7He located on our website at (www.tunl.duke.edu/NuclData/General_Tables/7he.shtml). See also Table Prev. Table 7.1 preview 7.1 [Table of Energy Levels] (in PDF or PS). Mass of 7He: The atomic mass excess of 7He is 26.11 ± 0.03 MeV:

  11. A=8B (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (See Energy Level Diagrams for 8B) GENERAL: References to articles on general properties of 8B published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 8B located on our website at (www.tunl.duke.edu/nucldata/General_Tables/8b.shtml). See also Table Prev. Table 8.15 preview 8.15 [Table of Energy Levels] (in PDF or PS). μ = 1.0355 ± 0.0003 μN: see (1996FIZY). Q = 68.3 ± 2.1 mb

  12. A=8He (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (See Energy Level Diagrams for 8He) GENERAL: References to articles on general properties of 8He published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 8He located on our website at (www.tunl.duke.edu/nucldata/General_Tables/8he.shtml). See also Table Prev. Table 8.1 preview 8.1 [Table of Energy Levels] (in PDF or PS). Mass of 8He: The atomic mass excess of 8He adopted by us and by

  13. A=9B (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (See Energy Level Diagrams for 9B) GENERAL: References to articles on general properties of 9B published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 9B located on our website at (www.tunl.duke.edu/nucldata/General_Tables/9b.shtml). See also Table Prev. Table 9.13 preview 9.13 [Table of Energy Levels] (in PDF or PS). The low-lying levels of 9B have mainly [441] spatial symmetry and

  14. A=9Be (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (See Energy Level Diagrams for 9Be) GENERAL: References to articles on general properties of 9Be published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 9Be located on our website at (www.tunl.duke.edu/nucldata/General_Tables/9be.shtml). See also Table Prev. Table 9.2 preview 9.2 [Table of Energy Levels] (in PDF or PS). μ = -1.1778 ± 0.0009 μN: see (1978LEZA); Q = 52.88 ± 0.38 mb:

  15. A=9C (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (See Energy Level Diagrams for 9C) GENERAL: References to articles on general properties of 9C published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 9C located on our website at (www.tunl.duke.edu/nucldata/General_Tables/9c.shtml). See also Table Prev. Table 9.16 preview 9.16 [Table of Energy Levels] (in PDF or PS). Ground state properties: μ = -1.3914 ± 0.0005 μN (1996MA38). See

  16. A=9He (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (See the Isobar Diagram for 9He) GENERAL: References to articles on general properties of 9He published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 9He located on our website at (www.tunl.duke.edu/nucldata/General_Tables/9he.shtml). Mass of 9He: Although the value adopted in the 2003 Atomic Mass Evaluation (2003AU02) for the 9He ground state is 40.939 ± 0.029 MeV based on the results

  17. A=9Li (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (See Energy Level Diagrams for 9Li) GENERAL: References to articles on general properties of 9Li published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 9Li located on our website at (www.tunl.duke.edu/nucldata/General_Tables/9li.shtml). See also Table Prev. Table 9.1 preview 9.1 [Table of Energy Levels] (in PDF or PS). Ground state properties: μ = 3.4391 ± 0.0006 μN (1983CO11). See

  18. A=9N (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (Not illustrated) Not observed: see (1988AJ01). Mass excesses of 46.56 and 46.40 MeV have been estimated from two different mass formulae (2000PO32). 9N would then be proton unbound by ~ 4 MeV. However, mass formulae neither take into account the fact that the last occupied orbit(s) may change near the drip lines nor the fact that an extended low-l orbit leads to a lowered Coulomb energy. The suggested s-wave ground-state of 9He and a Coulomb energy estimated from the 11N ground state

  19. Stability of Y-Ti-O Precipitates ...

    Office of Scientific and Technical Information (OSTI)

    ... Sci., 1992, 27, 2687-2694. 5 B. J. Inkson, P. L. Threadgill, 'Friction welding of FeAl40 grade 3 ODS alloy'Mater. Sci. Eng. A, 1998, 258, 313-318. 6 H. Ates, M. Turker, A. ...

  20. A Study of Selected Properties and Applications of AlMgB14 and Related Composites: Ultra-Hard Materials

    SciTech Connect (OSTI)

    Theron L. Lewis

    2002-05-28

    This research presents a study of the hardness, electrical, and thermal properties AlMgB{sub 14} containing Al{sub 2}MgO{sub 4} spinel. This research also investigated how much Al{sub 2}MgO{sub 4} spinel consistently forms with AlMgB{sub 14}, if AlMgB{sub 14} materials can be produced by hot isostatic pressing (HIP), what effects TiC and TiB{sub 2} have on this composite material, and the importance of mechanical alloying. Included also is a study of the variation in hardness measurements and how they relate to SI units. Heretofore, all ultra-hard materials (hardness > 40 GPA) have been found to be cubic in structure, electrical insulators, and expensive; the behavior of AlMgB{sub 14}, which in certain specimens and compositions can have hardness values greater than 40 GPa, is therefore quite unusual since it is non-cubic, conductive, and moderate in cost. This offers an opportunity to investigate the relationship between hardness, thermal, and electrical properties from a new perspective. The main purpose of this project was to characterize the different properties of the AlMgB{sub 14} materials and to demonstrate that this material can be made in bulk. The technologies used for this study include microhardness measurement techniques, scanning electron microscopy, energy dispersive spectroscopy, x-ray diffraction spectroscopy, x-ray diffraction spectroscopy at different temperatures, optical microscopy, thermomechanical analysis, differential thermal analysis, 4-point probe resistivity, density techniques, Seebeck Effect, and Hall Effect. This research may lead to use of this material for applications where high abrasion resistance along with electrical conduction is needed. Also this research gave more information about a material that could have a great impact on industrial applications.

  1. Synthesis of AlN/Al Polycrystals along with Al Nanoparticles Using Thermal Plasma Route

    SciTech Connect (OSTI)

    Kanhe, Nilesh S.; Nawale, A. B.; Kulkarni, N. V.; Bhoraskar, S. V.; Mathe, V. L.; Das, A. K.

    2011-07-15

    This paper for the first time reports the (200) oriented growth of hexagonal Aluminum nitride crystals during synthesis of aluminum nanoparticles in dc transferred arc thermal plasma reactor by gas phase condensation in nitrogen plasma. The structural and morphological study of as synthesized AlN crystal and aluminium nanoparticles was done by using the x-ray diffraction method, scanning electron microscopy and transmission electron microscopy.

  2. Fabrication of TiO{sub 2} Thick Film for Photocatalyst from Commercial TiO{sub 2} Powder

    SciTech Connect (OSTI)

    Asteti, S. Fuji; Syarif, D. Gustaman

    2008-03-17

    Photocatalytic activity of TiO{sub 2} thick film ceramics made of commercial TiO{sub 2} powder has been studied. The TiO{sub 2} powder was nano sized one that was derived from dried TiO{sub 2} suspension. The TiO{sub 2} suspension was made by pouring some blended commercial TiO{sub 2} powder into some amount of water. The paste of TiO{sub 2} was made by mixing the nano sized TiO{sub 2} powder with organic vehicle and glass frit. The paste was spread on a glass substrate. The paste was dried at 100 deg. C and heated at different temperatures (400 deg. C and 500 deg. C) for 60 minutes to produce thick film ceramics. The photocatalytic activity of these films was evaluated by measuring the concentration of a solution of methylene blue where the thick films were inside after being illuminated by UV light at various periods of times. The initial concentration of the methylene blue solution was 5 ppm. Structural analyses were carried out by X-ray diffraction (XRD). The XRD analyses showed that the produced thick film ceramic had mainly crystal structure of anatase. According to the photocatalytical data, it was known that the produced thick film ceramics were photocatalyst which were capable of decomposing an organic compound such as the methylene blue.

  3. Electrostatic carrier doping of GdTiO{sub 3}/SrTiO{sub 3} interfaces

    SciTech Connect (OSTI)

    Moetakef, Pouya; Cain, Tyler A.; Zhang, Jack Y.; Janotti, Anderson; Van de Walle, Chris G.; Stemmer, Susanne; Ouellette, Daniel G.; Allen, S. James; Klenov, Dmitri O.; Rajan, Siddharth

    2011-12-05

    Heterostructures and superlattices consisting of a prototype Mott insulator, GdTiO{sub 3}, and the band insulator SrTiO{sub 3} are grown by molecular beam epitaxy and show intrinsic electronic reconstruction, approximately 1/2 electron per surface unit cell at each GdTiO{sub 3}/SrTiO{sub 3} interface. The sheet carrier densities in all structures containing more than one unit cell of SrTiO{sub 3} are independent of layer thicknesses and growth sequences, indicating that the mobile carriers are in a high concentration, two-dimensional electron gas bound to the interface. These carrier densities closely meet the electrostatic requirements for compensating the fixed charge at these polar interfaces. Based on the experimental results, insights into interfacial band alignments, charge distribution, and the influence of different electrostatic boundary conditions are obtained.

  4. AL2002-01.pdf | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    2-01.pdf AL2002-01.pdf PDF icon AL2002-01.pdf More Documents & Publications AL2002-04.pdf AL2002-08.pdf AL2002-06...

  5. AL2002-04.pdf | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    4.pdf AL2002-04.pdf PDF icon AL2002-04.pdf More Documents & Publications AL2004-01r2.pdf AL2002-01.pdf AL2002-08...

  6. Microsoft Word - al2007-11.doc | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    al2007-11.doc Microsoft Word - al2007-11.doc PDF icon Microsoft Word - al2007-11.doc More Documents & Publications Acquisition Letter: AL2005-08 Microsoft Word - al2004-03.doc OPAM...

  7. ALS Operating Schedule on Google Calendar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Operating Schedule on Google Calendar Print ALS Operating Schedule Your browser does not appear to support JavaScript, but this page needs to use JavaScript to display...

  8. Al Corn Clean Fuel | Open Energy Information

    Open Energy Info (EERE)

    Corn Clean Fuel Jump to: navigation, search Name: Al-Corn Clean Fuel Place: Claremont, North Dakota Product: Al-Corn is an ethanol plant located in Claremont, North Dakota, which...

  9. Promising Magnesium Battery Research at ALS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Promising Magnesium Battery Research at ALS Promising Magnesium Battery Research at ALS Print Wednesday, 23 January 2013 16:59 toyota battery a) Cross-section of the in situ ...

  10. Category:Montgomery, AL | Open Energy Information

    Open Energy Info (EERE)

    Montgomery, AL Jump to: navigation, search Go Back to PV Economics By Location Media in category "Montgomery, AL" The following 16 files are in this category, out of 16 total....

  11. Aluminium distribution in ZSM-5 revisited: The role of Al-Al interactions

    SciTech Connect (OSTI)

    Ruiz-Salvador, A. Rabdel; Grau-Crespo, Ricardo; Gray, Aileen E.; Lewis, Dewi W.

    2013-02-15

    We present a theoretical study of the distribution of Al atoms in zeolite ZSM-5 with Si/Al=47, where we focus on the role of Al-Al interactions rather than on the energetics of Al/Si substitutions at individual sites. Using interatomic potential methods, we evaluate the energies of the full set of symmetrically independent configurations of Al siting in a Si{sub 94}Al{sub 2}O{sub 192} cell. The equilibrium Al distribution is determined by the interplay of two factors: the energetics of the Al/Si substitution at an individual site, which tends to populate particular T sites (e.g., the T14 site), and the Al-Al interaction, which at this Si/Al maximises Al-Al distances in general agreement with Dempsey's rule. However, it is found that the interaction energy changes approximately as the inverse of the square of the distance between the two Al atoms, rather than the inverse of the distance expected if this were merely charge repulsion. Moreover, we find that the anisotropic nature of the framework density plays an important role in determining the magnitude of the interactions, which are not simply dependent on Al-Al distances. - Graphical abstract: Role of Al-Al interactions in high silica ZSM-5 is shown to be anisotropic in nature and not dependent solely on Coulombic interactions. Highlights: Black-Right-Pointing-Pointer Si-Al distribution in ZSM-5 is revisited, stressing the role of the Al-Al interaction. Black-Right-Pointing-Pointer Coulomb interactions are not the key factors controlling the Al siting. Black-Right-Pointing-Pointer Anisotropy of the framework is identified as a source of departure from Dempsey's rule.

  12. Development of Ti/Ti{sub 3}Sn functionally gradient material produced by eutectic bonding method

    SciTech Connect (OSTI)

    Kirihara, S.; Takeda, M.; Tsujimoto, T. [Ibaraki Univ., Hitachi (Japan). Faculty of Engineering] [Ibaraki Univ., Hitachi (Japan). Faculty of Engineering

    1996-07-15

    Although many materials which have a single function have been developed, future needs are anticipated to include materials which have various functions. A functionally gradient material (FGM) which has characteristics of two different materials is a promising candidate for multi-functional material. The present methods for production of FGM, however, are very complicated and costly. In this study the authors answer the serious problem of high production cost by fabricating the FGM by a eutectic bonding method. This fabrication method includes structural control of FGM by changing the cooling process. They describe Ti/Ti{sub 3}Sn FGM obtained by the eutectic bonding method, and tell how the structure of its composition gradient part is changed by controlling the cooling process.

  13. Band alignment in visible-light photo-active CoO/SrTiO{sub 3} (001) heterostructures

    SciTech Connect (OSTI)

    Seo, Hosung; Demkov, Alexander A.

    2014-12-28

    Epitaxial oxide heterostructures are of fundamental interest in a number of problems ranging from oxide electronics to model catalysts. The epitaxial CoO/SrTiO{sub 3} (001) heterostructure on Si(001) has been recently studied as a model oxide catalyst for water splitting under visible light irradiation (Ngo et al., J. Appl. Phys. 114, 084901 (2013)). We use density functional theory to investigate the valence band offset at the CoO/SrTiO{sub 3} (001) interface. We examine the mechanism of charge transfer and dielectric screening at the interface and demonstrate that charge transfer is mediated by the metal-induced gap states in SrTiO{sub 3}, while the dielectric screening at the interface is largely governed by the ionic polarization of under-coordinated oxygen. Based on this finding, we argue that strain relaxation in CoO plays a critical role in determining the band offset. We find that the offsets of 1.36–1.10 eV, calculated in the Schottky-limit are in excellent agreement with the experimental value of 1.20 eV. In addition, we investigate the effect of the Hubbard correction, applied on the Co 3d states, on the dipole layer and potential shift at the interface.

  14. Tes Co Ltd | Open Energy Information

    Open Energy Info (EERE)

    Product: Korean manufacturer of semiconductor capital equipment; works with LG Electronics to build PECVD equipment Coordinates: 37.22229, 127.227028 Show Map Loading...

  15. Nondestructive evaluation of Ni-Ti shape memory alloy

    SciTech Connect (OSTI)

    Meir, S.; Gordon, S.; Karsh, M.; Ayers, R.; Olson, D. L.; Wiezman, A.

    2011-06-23

    The nondestructive evaluation of nickel titanium (Ni-Ti) alloys for applications such as heat treatment for biomaterials applications (dental) and welding was investigated. Ni-Ti alloys and its ternary alloys are valued for mechanical properties in addition to the shape memory effect. Two analytical approaches were perused in this work. Assessment of the microstructure of the alloy that determines the martensitic start temperature (Ms) of Ni-Ti alloy as a function of heat treatment, and secondly, an attempt to evaluate a Friction Stir Welding, which involves thermo-mechanical processing of the alloy.

  16. A=16B (1993TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    93TI07) (Not illustrated) This nucleus has not been observed in the 4.8 GeV proton bombardment of a uranium target. It is particle unstable. Its mass excess is predicted to be 37.97 MeV; it would then be unstable with respect to decay into 15B + n by 0.93 MeV. See (1985WA02, 1986AJ04). The ground state is predicted to have Jπ = 0- and the first three excited states are predicted to lie at 0.95, 1.10, and 1.55 MeV [Jπ = 2-, 3-, 4-] in a (0 + 1)ℏω space shell model calculation. See (1983ANZQ,

  17. A=16C (1993TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    93TI07) (See Energy Level Diagrams for 16C) GENERAL: See Table Prev. Table 16.1 preview 16.1 [General Table] (in PDF or PS) and Table Prev. Table 16.2 preview 16.2 [Table of Energy Levels] (in PDF or PS) here. 1. 16C(β-)16N Qm = 8.012 The half life of 16C is 0.747 ± 0.008 sec. It decays to 16N*(0.12, 3.35, 4.32) [Jπ = 0-, 1+, 1+]: see Table Prev. Table 16.3 preview 16.3 (in PDF or PS) and (1993CH06). See also (1986AJ04) and see (1986KI05, 1988WA1E, 1992WA1L) for theoretical discussions of

  18. A=16Ne (1993TI07)

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    93TI07) (See the Isobar Diagram for 16Ne) GENERAL: See Table Prev. Table 16.29 preview 16.29 [General Table] (in PDF or PS) and Table Prev. Table 16.32 preview 16.32 [Table of Energy Levels] (in PDF or PS). Mass of 16Ne: The Q-values of the 20Ne(α, 8He) and 16O(π+, π-) reactions lead to atomic mass excesses of 23.93 ± 0.08 MeV (1978KE06), 23.978 ± 0.024 MeV (1983WO01) and 24.048 ± 0.045 MeV (1980BU15) [recalculated using the (1985WA02) masses for 8He, 16O and 20Ne]. The weighted mean is

  19. A=17C (1993TI07)

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    93TI07) (See the Isobar Diagram for 17C) The atomic mass excess given by (1988WA18) for 17C is 21035 ± 17 keV. See also (1986AN07). 17C is then stable with respect to 16C + n by 0.73 MeV. Eβ- (max) to 17Ng.s. = 13.16 MeV. See also (1986BI1A). The half-life of 17C has been measured to be 202 ± 17 msec (1986CU01), 220 ± 80 msec (1986DU07), 180 ± 31 msec (1988SA04), and 174 ± 31 msec (1991RE02). Relative intensities of β-delayed gammas were measured by (1986DU07, 1986HU1A, 1986JEZY) [see

  20. A=17Ne (1993TI07)

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    93TI07) (See the Isobar Diagram for 17Ne) GENERAL: See Table Prev. Table 17.26 preview 17.26 [Table of Energy Levels] (in PDF or PS). 1. (a) 17Ne(β+)17F* → 16O + p Qm = 13.928 (b) 17Ne(β+)17F → 13N + α Qm = 8.711 (c) 17Ne(β+)17F Qm = 14.529 The half-life of 17Ne has been reported as 109.0 ± 1.0 msec (1971HA05) and 109.3 ± 0.6 msec (1988BO39): the weighted mean is 109.2 ± 0.6 and we adopt it. The decay is primarily to the proton unstable states of 17F at 4.65, 5.49, 6.04 and 8.08 MeV

  1. A=18B (1995TI07)

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    95TI07) (Not illustrated) 18B has not been observed in the bombardment of Ta by 44 MeV/A Ar ions (1985DE60, 1985LA03, 1986PO13) or in the bombardment of Be by 12 MeV/A 56Fe ions (1984MU27). 18B has been predicted to have a mass excess of 52.3 MeV (1993AU05). It would then be unstable with respect to 17B + n by 0.5 MeV: see (1978AJ03, 1985WA02). 18B is calculated to have Jπ = 4- and to have excited states at 0.62, 0.86 and 1.59 MeV with Jπ = 1-, 2- and 2- (1985PO10).The shell model calculations

  2. A=18F (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    95TI07) (See Energy Level Diagrams for 18F) GENERAL: See Table Prev. Table 18.23 preview 18.23 [General Table] (in PDF or PS) and Table Prev. Table 18.24 preview 18.24 [Table of Energy Levels] (in PDF or PS). μ1.12 = +2.86 ± 0.03 nm [see (1983AJ01)] Q1.12 = 0.13 ± 0.03 b [see (1983AJ01)]. 1. 18F(β+)18O Qm = 1.655 The positron decay is entirely to the ground state of 18O [Jπ = 0+, T = 1]; the half-life is 109.77 ± 0.05 min [see Table Prev. Table 18.11 preview 18.11 (in PDF or PS) in

  3. A=18N (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    95TI07) (See Energy Level Diagrams for 18N) GENERAL: See Table Prev. Table 18.3 preview 18.3 [General Table ] (in PDF or PS) and Table Prev. Table 18.4 preview 18.4 [Table of Energy Levels] (in PDF or PS). Mass of 18N: The atomic mass excess derived from the Q-value of the 18O(7Li, 7Be)18N reaction and adopted by (1993AU05) is 13.117 ± 0.020 MeV (1983PU01). 18N is then stable with respect to breakup into 17N + n by 2.825 MeV. See (1983AJ01) for the earlier work. 1. 18N(β-)18O Qm = -13.899 The

  4. A=18Ne (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    95TI07) (See Energy Level Diagrams for 18Ne) GENERAL: See Table Prev. Table 18.35 preview 18.35 [General Table] (in PDF or PS) and Table Prev. Table 18.36 preview 18.36 [Table of Energy Levels] (in PDF or PS). For B(E2) of 18Ne*(1.89) and other parameters see (1987RA01) and Table Prev. Table 2 preview 2 in the Introduction. 1. 18Ne(β+)18F Qm = 4.446 The half-life of 18Ne is 1672 ± 8 ms: see (1978AJ03) and (1983AD03). The decay is primarily to 18F*(0, 1.04, 1.70 MeV). In addition there is an

  5. A=19C (1995TI07)

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    95TI07) (See the Isobar Diagram for 19C) 19C has been observed in the 0.8 GeV proton bombardment of thorium (1986VI09, 1988WO09) and in the fragmentation of 66 MeV/A argon ions (1987GI05) and in 44 MeV/A 22Ne on 181Ta, and in 112 MeV/A 20Ne on 12C (1994RAZW, 1995OZ02). The mass excess adopted by (1993AU05) is 32.23 ± 0.11 MeV. See also (1986VI09, 1987GI05, 1988WO09, 1991OR01). 19C is then stable with respect to decay into 18C + n by 0.16 MeV and into 17C + 2n by 4.35 MeV. The half-life was

  6. A=19N (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    95TI07) (See the Isobar Diagram for 19N) 19N has been produced in a number of different multinucleon transfer reactions (1983AJ01, 1987AJ02), and these results lead to an adopted value (1993AU05) of 15.860 ± 0.016 MeV for the mass excess. 19N is then stable with respect to decay into 18N + n by 5.33 MeV. The half-life has been measured to be 0.32 ± 0.10 s (1986DU07), 0.21+0.2-0.1 s (1988MU08), 0.235 ± 0.032 s (1988SA04), 0.300 ± 0.080 s (1988DUZT), 0.329 ± 0.019 s (1991RE02). The neutron

  7. A=19Na (1995TI07)

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    95TI07) (See the Isobar Diagram for 19Na) This nucleus was observed in the 24Mg(p, 6He)19Na reaction at Ep = 54.7 MeV (1969CE01). A study via the 24Mg(3He, 8Li)19Na reaction at E(3He) = 76.3 MeV leads to an atomic mass excess of 12.929 ± 0.012 MeV for 19Na; it is then unstable with respect to breakup into 18Ne + p by 321 ± 13 keV. An excited state at Ex = 120 ± 10 keV is also reported (1975BE38, 1993AU05). See also (1987AJ02) and (1987PO01, 1987SA24, 1988CO15, 1990PO04, 1992AV03

  8. A=19Ne (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    95TI07) (See Energy Level Diagrams for 19Ne) GENERAL: See Table Prev. Table 19.26 preview 19.26 [General Table] (in PDF or PS) and Table Prev. Table 19.27 preview 19.27 [Table of Energy Levels] (in PDF or PS) here. μg.s. = -1.88542 (8) nm (1982MA39) μ0.239 = -0.740 (8) nm (1978LEZA) 1. 19Ne(β+)19F Qm = 3.238 We adopt the half-life of 19Ne suggested by (1983AD03): 17.34 ± 0.09 s. See also (1978AJ03). The decay is principally to 19Fg.s.: see Table Prev. Table 19.29 preview 19.29 (in PDF or

  9. A=19O (1995TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    95TI07) (See Energy Level Diagrams for 19O) GENERAL: See Table Prev. Table 19.1 preview 19.1 [General Table] (in PDF or PS) and Table Prev. Table 19.2 preview 19.2 [Table of Energy Levels] (in PDF or PS) here. 1. 19O(β-)19F Qm = 4.819 The weighted mean of several half-lives is 26.96 ± 0.07 s: see (1972AJ02, 1987AJ02). The decay is complex: see reaction 34 of 19F and Table Prev. Table 19.23 preview 19.23 (in PDF or PS) and Table Prev. Table 19.24 preview 19.24 (in PDF or PS). 2. 9Be(18O,

  10. A=20F (1998TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    98TI06) (See Energy Level Diagrams for 20F) GENERAL: See Table Prev. Table 20.4 preview 20.4 [General Table] (in PDF or PS) and Table Prev. Table 20.5 preview 20.5 [Table of Energy Levels] (in PDF or PS) here. μ = +2.0935 (9) nm (1989RA17) Q = -0.042 (3) b (1989RA17) 1. 20F(β-)20Ne Qm = 7.025 The half-life of 20F is (11.163 ± 0.008) s (1992WA04), (11.11 ± 0.04) s (1995IT1C). For earlier measurements see (1987AJ02). 20F decays principally to 20Ne*(1.63): see 20Ne, reaction 37. 2. (a) 6Li(15N,

  11. A=20Mg (1998TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    98TI06) (See the Isobar Diagram for 20Mg) 20Mg has been populated in the 24Mg(α, 8He) reaction at Eα = 127 and 156 MeV, in the 20Ne(3He, 3n) reaction at E(3He) = 70 MeV, and more recently in projectile fragmentation reactions. Reviews of proton rich nuclei and methods of production are presented in (1989AYZU, 1993SO13). See also (1990PO04). The super-allowed decay of 20Mg to the first T = 2 (Jπ = 0+) state of 20Na [Ex = 6.534 ± 0.013 MeV (1995PI03)] has been reported in early work (1979MO02,

  12. A=20Na (1998TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    98TI06) (See Energy Level Diagrams for 20Na) GENERAL: See Table Prev. Table 20.32 preview 20.32 [General Table] (in PDF or PS) and Table Prev. Table 20.33 preview 20.33 [Table of Energy Levels] (in PDF or PS) here. μ = 0.3694 ± 0.0002 nm (1975SC20, 1989RA17) 1. 20Na(β+)20Ne Qm = 13.887 20Na decays by positron emission to 20Ne*(1.63) and to a number of other excited states of 20Ne: see Table Prev. Table 20.31 preview 20.31 (in PDF or PS) and reaction 59 in 20Ne. The half-life of 20Na is 447.9

  13. A=3H (1987TI07)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1987TI07) (Not illustrated) GENERAL: Ground State: Jπ = 1/2+, μ = 2.978960 ± 0.000001 nm, M - A = 14.94991 ± 0.00003 MeV. The wave function for the triton bound state is calculated to be mostly S-state (~ 90%) with S'-state (~ 1%) and D-state (~ 9%) admixtures depending on the potentials used (1979SA15, 1986IS06). See also (1980HA10, 1980LO091983FR19, 1984CI05, 1984CI09, 1984MU23). The measured magnetic moment for 3H is μ = 2.978960 ± 0.000001 nm (1978LEZA). Calculations which include both

  14. A=4n (1992TI02)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    4n (1992TI02) GENERAL: The stability of 8He (1968BA48, 1968ME03, 1973FI04, 1988AJ01) sets an upper limit to the total binding energy of 4n, because the decay 8He → 4He + 4n does not occur (1964GO1B, 1964GO25). The most precisely determined mass excess of 8He (1988WA18) yields B(4n) ≤ 3.1 MeV. Noting that in all known nuclei the proton binding energy increases when two neutrons are added, (1964VL1A) show that B(4n) < -Q, where Q is the decay energy for 5H → 3H + 2n. Since Q > 0

  15. A=7B (2002TI10)

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    2002TI10) (See the Isobar Diagram for 7B) The mass excess of 7B adopted by (1997AU04) is 27.870 ± 0.070 MeV. It was obtained by averaging the values of 27.94 ± 0.10 MeV from the 10B(3He, 6He)7B reaction (1967MC14, 1988AJ01) and the value 27.800 ± 0.10 MeV obtained in the 7Li(π+, π-)7B reaction (1981SE1B). The width of the ground state is Γ = 1.4 ± 0.2 MeV: see (1967MC14, 1988AJ01). 7B is unbound with respect to 6Be + p, 5Li + 2p and 4He + 3p by 2.21, 1.61 and 3.38 MeV, respectively. The

  16. A=8Be (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (See Energy Level Diagrams for 8Be) GENERAL: References to articles on general properties of 8Be published since the previous review (1988AJ01) are grouped into categories and listed, along with brief descriptions of each item, in the General Tables for 8Be located on our website at (www.tunl.duke.edu/nucldata/General_Tables/8be.shtml). See also Table Prev. Table 8.9 preview 8.9 [Table of Energy Levels] (in PDF or PS). 1. 8Be → 4He4He Qm = 0.0918 Γcm for 8Beg.s. = 5.57 ± 0.25 eV:

  17. A=8C (2004TI06)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    2004TI06) (See the Isobar Diagram for 8C) Mass of 8C: The atomic mass excess of 8C is 35094 ± 23 keV (2003AU03); Γcm = 230 ± 50 keV [Jπ = 0+; T = 2]: see (1979AJ01). 8C is stable with respect to 7B + p (Q = -0.07 MeV) and unstable with respect to 6Be + 2p (Q = 2.14), 5Li + 3p (Q = 1.55) and 4He + 4p (Q = 3.51). At E(3He) = 76 MeV the differential cross section for formation of 8Cg.s. in the 14N(3He, 9Li) reaction is ~ 5 nb/sr at θlab = 10°. The 12C(α, 8He)8C reaction has been studied at

  18. Modeling and experimental studies of oxide covered metal surfaces: TiO{sub 2}/Ti a model system. Progress report

    SciTech Connect (OSTI)

    Smyrl, W.H.

    1991-12-31

    Prior work in our laboratories at the Corrosion Research Center has shown that thin, anodic TiO{sub 2} films formed by the Slow Growth Mode (SGM) on polycrystalline titanium and microcrystalline with a texture that varies from one metal grain to another. Furthermore, the underlying metal grains are mapped by the photoelectrochemical response of the oxide. The same characteristics have also been demonstrated in our laboratory for ZnO grown on Zn. The TiO{sub 2}/Ti system has been chosen for study both because of its importance in energy systems, and because it can serve as a model system for other metal-metal oxide couples. The investigations of anodic TiO{sub 2} films on Ti have shown that the properties of thin films are consistent with the rutile form of the oxide. Both experimental data and theoretical calculations show the close resemblance to results on single crystal TiO{sub 2}. Furthermore, the modeling studies reveal that the optical transitions near the bandedge arise from the bulk band structure. The photoelectrochemical properties of anodic TiO{sub 2} films have now been shown to obey the simple Gaertner-Butler model for the semiconductor-electrolyte interface, with a few modifications. The most important deviation has now been shown to be a result of multiple internal reflections in the oxide film.

  19. Modeling and experimental studies of oxide covered metal surfaces: TiO sub 2 /Ti a model system

    SciTech Connect (OSTI)

    Smyrl, W.H.

    1991-01-01

    Prior work in our laboratories at the Corrosion Research Center has shown that thin, anodic TiO{sub 2} films formed by the Slow Growth Mode (SGM) on polycrystalline titanium and microcrystalline with a texture that varies from one metal grain to another. Furthermore, the underlying metal grains are mapped by the photoelectrochemical response of the oxide. The same characteristics have also been demonstrated in our laboratory for ZnO grown on Zn. The TiO{sub 2}/Ti system has been chosen for study both because of its importance in energy systems, and because it can serve as a model system for other metal-metal oxide couples. The investigations of anodic TiO{sub 2} films on Ti have shown that the properties of thin films are consistent with the rutile form of the oxide. Both experimental data and theoretical calculations show the close resemblance to results on single crystal TiO{sub 2}. Furthermore, the modeling studies reveal that the optical transitions near the bandedge arise from the bulk band structure. The photoelectrochemical properties of anodic TiO{sub 2} films have now been shown to obey the simple Gaertner-Butler model for the semiconductor-electrolyte interface, with a few modifications. The most important deviation has now been shown to be a result of multiple internal reflections in the oxide film.

  20. Controlling Atomic Layer Deposition of TiO2 in Aerogels through Surface Functionalization

    SciTech Connect (OSTI)

    Ghosal, S; Baumann, T F; King, J S; Kucheyev, S; Wang, Y; Worsley, M A; Biener, J; Bent, S F; Hamza, A V

    2009-03-09

    This report demonstrates a chemical functionalization method for controlling atomic layer deposition (ALD) of TiO{sub 2} in low-density nanoporous materials. Functionalization of silica aerogel with trimethylsilane is shown to strongly suppress TiO{sub 2} growth via ALD. Subsequent modification of the functionalization through selective removal of the hydrocarbon groups reactivates the aerogel towards TiO{sub 2} deposition. These results demonstrate the potential use of ALD as a selective tool for creating novel nanoporous materials. Nanoporous materials present significant technological advantage for a wide range of applications, including catalysis, energy storage and conversion, nanoelectronics to name just a few (1-4). Hence, there is considerable interest in developing synthetic pathways for the fabrication of nanoporous materials with tailored properties. Aerogels (AGs) are unique low-density, open-cell porous materials consisting of submicrometer pores and ligaments that can be used as a robust material platform for designing novel nanoporous materials. In recent years, a synthetic approach based on ALD on AG templates has emerged as a promising method for the directed growth of nanoporous materials (5-11, 18). This approach has been used successfully to prepare millimeter-sized high aspect ratio aerogels coated uniformly with zinc oxide (ZnO), tungsten (W) and alumina (Al{sub 2}O{sub 3}) (10, 11). The ALD process utilizes two sequential, self-limiting surface reactions resulting in a layer-by-layer growth mode. The self limiting nature of the surface reactions makes ALD a particularly suitable technique for uniform deposition onto high aspect ratio porous substrates. Additionally, chemical specificity of the surface reactions in ALD enables one to control the deposition process through selective functionalization of the substrate surface. In fact the functionalization of planar substrates such as silicon wafers with organosilane groups (R{sub n}SiX{sub 4-n

  1. Strain-Dependence of the Structure and Ferroic Properties of Epitaxial NiTiO 3 Thin Films Grown on Different Substrates

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Varga, Tamas; Droubay, Timothy C.; Bowden, Mark E.; Kovarik, Libor; Hu, Dehong; Chambers, Scott A.

    2015-01-01

    Polarization-induced weak ferromagnetism has been predicted a few years back in perovskite MTiO 3 (M = Fe, Mn, and Ni). We set out to stabilize this metastable perovskite structure by growing NiTiO 3 epitaxially on different substrates and to investigate the dependence of polar and magnetic properties on strain. Epitaxial NiTiO 3 films were deposited on Al 2 O 3 , Fe 2 O 3 , and LiNbO 3 substrates by pulsed laser deposition and characterized using several techniques. The effect of substrate choice on lattice strain, film structure, and physical properties was investigated. Our structural data from X-raymore » diffraction and electron microscopy shows that substrate-induced strain has a marked effect on the structure and crystalline quality of the films. Physical property measurements reveal a dependence of the weak ferromagnetism and lattice polarization on strain and highlight our ability to control the ferroic properties in NiTiO 3 thin films by the choice of substrate. Our results are also consistent with the theoretical prediction that the ferromagnetism in acentric NiTiO 3 is polarization induced. From the substrates studied here, the perovskite substrate LiNbO 3 proved to be the most promising one for strong multiferroism.« less

  2. Strain-Dependence of the Structure and Ferroic Properties of Epitaxial NiTiO3Thin Films Grown on Different Substrates

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Varga, Tamas; Droubay, Timothy C.; Bowden, Mark E.; Kovarik, Libor; Hu, Dehong; Chambers, Scott A.

    2015-01-01

    Polarization-induced weak ferromagnetism has been predicted a few years back in perovskite MTiO3(M = Fe, Mn, and Ni). We set out to stabilize this metastable perovskite structure by growing NiTiO3epitaxially on different substrates and to investigate the dependence of polar and magnetic properties on strain. Epitaxial NiTiO3films were deposited on Al2O3, Fe2O3, and LiNbO3substrates by pulsed laser deposition and characterized using several techniques. The effect of substrate choice on lattice strain, film structure, and physical properties was investigated. Our structural data from X-ray diffraction and electron microscopy shows that substrate-induced strain has a marked effect on the structure and crystallinemorequality of the films. Physical property measurements reveal a dependence of the weak ferromagnetism and lattice polarization on strain and highlight our ability to control the ferroic properties in NiTiO3thin films by the choice of substrate. Our results are also consistent with the theoretical prediction that the ferromagnetism in acentric NiTiO3is polarization induced. From the substrates studied here, the perovskite substrate LiNbO3proved to be the most promising one for strong multiferroism.less

  3. Strain-dependence Of The Structure And Ferroic Properties Of Epitaxial NiTiO3 Thin Films Grown On Different Substrates

    SciTech Connect (OSTI)

    Varga, Tamas; Droubay, Timothy C.; Bowden, Mark E.; Kovarik, Libor; Hu, Dehong; Chambers, Scott A.

    2015-08-14

    Polarization-induced weak ferromagnetism has been predicted a few years back in perovskite MTiO3 (M = Fe, Mn, Ni) [Fennie, Phys. Rev. Lett. 100, 167203 (2008)]. We set out to stabilize this metastable perovskite structure by growing NiTiO3 epitaxially on different substrates, and to investigate the dependence of polar and magnetic properties on strain. Epitaxial NiTiO3 films were deposited on Al2O3, Fe2O3, and LiNbO3 substrates by pulsed laser deposition, and characterized using several techniques. The effect of substrate choice on lattice strain, film structure, and physical properties was investigated. Our structural data from x-ray diffraction and electron microscopy shows that substrate-induced strain has a marked effect on the structure and crystalline quality of the films. Physical property measurements reveal a dependence of the weak ferromagnetism and lattice polarization on strain, and highlight our ability to control the ferroic properties in NiTiO3 thin films by the choice of substrate. Our results are also consistent with the theoretical prediction that the ferromagnetism in acentric NiTiO3 is polarization-induced. From the substrates studied here, the perovskite substrate LiNbO3 proved to be the most promising one for strong multiferroism.

  4. Photoinduced electron transfer in perylene-TiO2 nanoassemblies

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ABSTRACT: The photosensitization effect of three perylene dye derivatives on titanium dioxide nanoparticles (TiO2 NPs) has been investigated. The dyes used, 1,7-dibromoperylene-3,4...

  5. Vacuum induction melting of Ti-6Ai-4V in a cold crucible. Report of Investigations/1988

    SciTech Connect (OSTI)

    Paige, J.I.

    1988-05-01

    The effect of fluoride inclusions on the properties of titanium produced from the Bureau of Mines-developed induction slag-melting process is of concern to the titanium industry. The objective of the research was to determine the effect of removing the nonconductive molten calcium fluoride (CaF/sub 2/) slag used as an insulator between the titanium and the segmented copper crucible. The data were obtained from single-induction-melted ingots prepared with no CaF/sub 2/ insulating slag and an ingot prepared with the normal addition of 4% CaF/sub 2/ slag. The results showed that the mechanical properties of single-induction-slag-melted and annealed Ti-6Al-4V alloy exceed the minimum values specified in Aerospace Materials Specification for Titanium Alloy Bars and Forgings AMS4928H. High-cycle, tension-tension fatigue testing yielded similar results. The data from 44 of the 45 specimens were contained within the typical scatter band for fatigue data on wrought Ti-6Al-4V alloy. Although the removal of the insulating slag is a desirable change, the data from the specimens with the previously standard 4% slag addition showed no detrimental effect from the slag inclusions.

  6. Martensite transformation of epitaxial Ni-Ti films

    SciTech Connect (OSTI)

    Buschbeck, J.; Kozhanov, A.; Kawasaki, J. K.; James, R. D.; Palmstroem, C. J.

    2011-05-09

    The structure and phase transformations of thin Ni-Ti shape memory alloy films grown by molecular beam epitaxy are investigated for compositions from 43 to 56 at. % Ti. Despite the substrate constraint, temperature dependent x-ray diffraction and resistivity measurements reveal reversible, martensitic phase transformations. The results suggest that these occur by an in-plane shear which does not disturb the lattice coherence at interfaces.

  7. Microstructure of V-based ohmic contacts to AlGaN/GaN heterostructures at a reduced annealing temperature

    SciTech Connect (OSTI)

    Schmid, A. Schroeter, Ch.; Otto, R.; Heitmann, J.; Schuster, M.; Klemm, V.; Rafaja, D.

    2015-02-02

    Ohmic contacts with V/Al/Ni/Au and V/Ni/Au metalization schemes were deposited on AlGaN/GaN heterostructures. The dependence of the specific contact resistance on the annealing conditions and the V:Al thickness ratio was shown. For an optimized electrode stack, a low specific contact resistance of 8.9??10{sup ?6} ? cm{sup 2} was achieved at an annealing temperature of 650?C. Compared to the conventional Ti/Al/Ni/Au contact, this is a reduction of 150?K. The microstructure and contact formation at the AlGaN/metal interface were investigated by transmission electron microscopy including high-resolution micrographs and energy dispersive X-ray analysis. It was shown that for low-resistive contacts, the resistivity of the metalization has to be taken into account. The V:Al thickness ratio has an impact on the formation of different intermetallic phases and thus is crucial for establishing ohmic contacts at reduced annealing temperatures.

  8. A comparative study of precipitation effects in Ti only and Ti-V Ultra Low Carbon (ULC) strip steels

    SciTech Connect (OSTI)

    Ooi, S.W.; Fourlaris, G. . E-mail: g.fourlaris@swansea.ac.uk

    2006-04-15

    Two ULC steel grades were investigated, one based on combined vanadium and titanium additions and the other based on titanium only additions. It has been established that TiC formation during interphase precipitation retards grain growth of the {l_brace}111{r_brace} texture grains during continuous annealing and hence positively affects the r value of the Ti only steel. The formation of newly formed TiC precipitates on dislocations during continuous annealing has been found to result in an increase of the yield strength in both steel grades, as the annealing temperature is increased. It is also confirmed that VC particles formed during the coiling process dissolve during the continuous annealing cycles. Suitable continuous annealing cycles can be adopted to produce high formable steels with a bake hardening potential using the beneficial effects of combined Ti-V additions.

  9. IBM Probes Material Capabilities at the ALS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    IBM Probes Material Capabilities at the ALS IBM Probes Material Capabilities at the ALS Print Wednesday, 12 February 2014 11:05 Vanadium dioxide, one of the few known materials that acts like an insulator at low temperatures but like a metal at warmer temperatures, is a somewhat futuristic material that could yield faster and much more energy-efficient electronic devices. Researchers from IBM's forward-thinking Spintronic Science and Applications Center (SpinAps) recently used the ALS to gain

  10. IBM Probes Material Capabilities at the ALS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    IBM Probes Material Capabilities at the ALS IBM Probes Material Capabilities at the ALS Print Wednesday, 12 February 2014 11:05 Vanadium dioxide, one of the few known materials that acts like an insulator at low temperatures but like a metal at warmer temperatures, is a somewhat futuristic material that could yield faster and much more energy-efficient electronic devices. Researchers from IBM's forward-thinking Spintronic Science and Applications Center (SpinAps) recently used the ALS to gain

  11. Ringleader: Cobber Lam, ALS Systems Administrator

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cobber Lam, ALS Systems Administrator Print Cobber Lam started working at Berkeley Lab 10 years ago as a student assistant, while attending college at Cal State East Bay. Within two months, he was assigned to the ALS and has stayed put ever since. He used to be matrixed via IT, but last year he became a direct ALS employee. ALS IT support is divided between Lam and Tim Kellogg, with Lam being more forward-facing, dealing with users and staff, and Kellogg working on the back-end mostly with

  12. IBM Probes Material Capabilities at the ALS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Researchers from IBM's forward-thinking Spintronic Science and Applications Center (SpinAps) recently used the ALS to gain greater insight into vanadium dioxide's unusual phase ...

  13. Al Turi Biomass Facility | Open Energy Information

    Open Energy Info (EERE)

    NEEDS 2006 Database Retrieved from "http:en.openei.orgwindex.php?titleAlTuriBiomassFacility&oldid397128" Feedback Contact needs updating Image needs updating...

  14. Microsoft Word - AL2005-03.doc

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AL 2005-03 Acquisition Regulation Date 100804 ACQUISITION LETTER This Acquisition Letter is issued under the authority of the DOE and NNSA Procurement Executives. Subject:...

  15. April 27, 2015-Special ALS Colloquium

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Years Janos Kirz, ALS Abstract Rntgen's great discovery became an instant public sensation. Fascination with the "new kind of rays" that could reveal the structure of opaque...

  16. Al Tayyar Energy | Open Energy Information

    Open Energy Info (EERE)

    Jump to: navigation, search Name: Al Tayyar Energy Place: Abu Dhabi, United Arab Emirates Sector: Renewable Energy Product: Provides development capital and equity investments...

  17. Microsoft Word - al2006-12.doc

    Broader source: Energy.gov (indexed) [DOE]

    AL-2006-12 (092906) 7 III. What Procedures Ensure Effective Audit Management? Some strategies for managing required audit activity include: 1. Contracting officers should...

  18. Crystallographic Consulting Brings Research to the ALS

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of the participating research team (PRT) members at the Berkeley Center for Structural Biology (BCSB), which operates five ALS beamlines. As PRT members, companies are...

  19. Al Furat Petroleum Company | Open Energy Information

    Open Energy Info (EERE)

    Furat Petroleum Company Name: Al Furat Petroleum Company Place: Damascus, Syria Product: oil and hydrocarbon gas Year Founded: 1985 Phone Number: 00963-11- (6183333) Website:...

  20. ALS Reveals New State of Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Reveals New State of Matter ALS Reveals New State of Matter Print Wednesday, 13 October 2010 00:00 ALS user groups from Princeton and Stanford have been making waves this past year with several high-profile papers and extensive news coverage of their work on a new state of matter embodied by "topological insulators," materials that conduct electricity only on their surfaces. First identified at the ALS in 2007 by a Princeton team led by M. Zahid Hasan, topological insulators have

  1. Microsoft Word - Final MR AL.doc

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy No. AL 2009-01 Acquisition Regulation Date: 10062008 ACQUISITION ... Subject: Management Reserve and Contingency References: FAR Subpart 15.4 Contract Pricing ...

  2. Electronic structure of cation-codoped TiO{sub 2} for visible-light photocatalyst applications from hybrid density functional theory calculations

    SciTech Connect (OSTI)

    Long, Run; English, Niall J.

    2011-04-04

    The electronic structures of Mg/Ca- and/or Mo/W- (mono- and co-) doped anatase TiO{sub 2} have been investigated via generalized Kohn-Sham theory with the Heyd-Scuseria-Ernzerhof hybrid functional for exchange-correlation (J. Heyd et al., [J. Chem. Phys. 118, 8207 (2003)], J. Heyd et al., [J. Chem. Phys. 124, 219906 (2006)], and J. Paier et al., [J. Chem. Phys. 125, 249901 (2006)]), in the context of density functional theory. Gap narrowing is small for monodoping, which also creates impuritiy bands in the ''forbidden gap,'' either as acceptor or donor states, limiting possible utility as visible-light photocatalysts. However, codoping of Mg/Ca and Mo/W not only induces appreciable gap narrowing, but also serves to passivate the impurity bands, which can harvest visible-light to a greater extent. Considering ionic radii, Mg and Mo should constitute the best cation-pair.

  3. Native SrTiO3 (001) surface layer from resonant Ti L2,3 reflectance spectroscopy

    SciTech Connect (OSTI)

    Valvidares, Manuel; Huijben, Mark; Yu, Pu; Ramesh, Ramamoorthy; Kortright, Jeffrey

    2010-11-03

    We quantitatively model resonant Ti L2,3 reflectivity Rs,p(q, hn) from several SrTiO3 (001) single crystals having different initial surface preparations and stored in ambient conditions before and between measurements. All samples exhibit unexpected 300 K Rs(hn) - Rp(hn) anisotropy corresponding to weak linear dichroism and tetragonal distortion of the TiO6 octahedra indicating a surface layer with properties different from cubic SrTiO3. Oscillations in Rs(q) confirm a ubiquitous surface layer 2-3 nm thick that evolves over a range of time scales. Resonant optical constant spectra derived from Rs,p(hn) assuming a uniform sample are refined using a single surface layer to fit measured Rs(q). Differences in surface layer and bulk optical properties indicate that the surface is significantly depleted in Sr and enriched in Ti and O. While consistent with the tendency of SrTiO3 surfaces toward non-stoichiometry, this layer does not conform simply to existing models for the near surface region and apparently forms via room temperature surface reactions with the ambient. This new quantitative spectral modeling approach is generally applicable and has potential to study near-surface properties of a variety of systems with unique chemical and electronic sensitivities.

  4. AL 2014-06 ACQUISITION LETTERS REMAINING IN EFFECT | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AL 2014-06 ACQUISITION LETTERS REMAINING IN EFFECT AL 2014-06 ACQUISITION LETTERS REMAINING IN EFFECT AL 2014-06 ACQUISITION LETTERS REMAINING IN EFFECT Acquisition Letters (AL)...

  5. Microsoft Word - al2005-04.doc | Department of Energy

    Energy Savers [EERE]

    al2005-04.doc Microsoft Word - al2005-04.doc PDF icon Microsoft Word - al2005-04.doc More Documents & Publications AL2005-04ClassDeviation.pdf Microsoft Word - Matrixpart2.doc...

  6. Microsoft Word - AL2004-02.doc | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    Microsoft Word - AL2004-02.doc More Documents & Publications Microsoft Word - AL2005-02.doc Microsoft Word - al2005-04.doc Microsoft Word - AL-Omnibus FY 2009 Apr 22 2009 all...

  7. Microsoft Word - AL2006-08.doc | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    8.doc Microsoft Word - AL2006-08.doc PDF icon Microsoft Word - AL2006-08.doc More Documents & Publications AL2007-05.doc&0; Microsoft Word - AL2005-14.doc Microsoft Word - ...

  8. Microsoft Word - AL2005-03.doc | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    5-03.doc Microsoft Word - AL2005-03.doc PDF icon Microsoft Word - AL2005-03.doc More Documents & Publications Microsoft Word - AL2005-01.doc Microsoft Word - AL2006-08.doc ...

  9. Microsoft Word - al2005-06.doc | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    - al2005-06.doc PDF icon Microsoft Word - al2005-06.doc More Documents & Publications Microsoft Word - AL2006-01.doc OPAM Policy Acquisition Guides Acquisition Letter: AL2005-08...

  10. Microsoft Word - AL2008-05.doc | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Microsoft Word - AL2008-05.doc Microsoft Word - AL2008-05.doc Microsoft Word - AL2008-05.doc More Documents & Publications Microsoft Word - AL 2010-07 Acquistion Letters Remaining...

  11. Microsoft Word - al2004-03.doc | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    al2004-03.doc Microsoft Word - al2004-03.doc PDF icon Microsoft Word - al2004-03.doc More Documents & Publications Acquisition Letter: AL2005-08 OPAM Policy Acquisition Guides ...

  12. Microsoft Word - AL2005-10.doc | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AL2005-10.doc Microsoft Word - AL2005-10.doc Microsoft Word - AL2005-10.doc (133.11 KB) More Documents & Publications Microsoft Word - AL2005-16.doc Audit Report: IG-0860 Microsoft ...

  13. AL2010-01.pdf | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    1.pdf AL2010-01.pdf PDF icon AL2010-01.pdf More Documents & Publications G Microsoft Word - AL-Omnibus FY 2009 Apr 22 2009 all sections.doc Microsoft Word - AL-Consolidated Approps...

  14. AL2007-09.pdf | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    7-09.pdf AL2007-09.pdf PDF icon AL2007-09.pdf More Documents & Publications AL2007-04.pdf RL-2007OMCPIA.pdf AL2007-06.pdf...

  15. AL2007-04.pdf | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    4.pdf AL2007-04.pdf PDF icon AL2007-04.pdf More Documents & Publications Preliminary Notice of Violation, BWXT Y-12 LLC - EA-2007-04 AL2007-05.doc&0; AL2007-09...

  16. AL2007-06.pdf | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    6.pdf AL2007-06.pdf PDF icon AL2007-06.pdf More Documents & Publications AL2007-04.pdf AL2007-09.pdf RL-2007OMCPIA...

  17. Magneto-transport in LaTi{sub 1−x}Mn{sub x}O{sub 3}/SrTiO{sub 3} oxide heterostructures

    SciTech Connect (OSTI)

    Kumar, Pramod Dogra, Anjana Budhani, R. C.

    2014-04-24

    We report the growth of ultrathin film of Mn doped LaTiO{sub 3} on TiO{sub 2} terminated SrTiO{sub 3} (001) substrate by pulsed laser deposition (PLD) and their electrical transport characteristics including magnetoresistance (MR). Though the replacement of Mn in LaTiO{sub 3} at the Ti site in dilute limit does not affect the metallic behaviour of films but variation in resistance is observed. Normalised resistance behaviour is explained on the basis of variation in charge carriers and increased interaction between Mn atoms in the system under investigation.

  18. Direct imaging of LaAlO{sub 3}/SrTiO{sub 3} nanostructures using...

    Office of Scientific and Technical Information (OSTI)

    Determination of the nanoscale dimensions has previously required a destructive readout ... Images of conductive and insulating nanoscale features are achieved with feature sizes as ...

  19. Materials Data on Ca3Ti2AlSi3O14F (SG:2) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  20. Materials Data on Ca3TiAl2Si3O13F2 (SG:2) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  1. Materials Data on SrLa4TiAl4O15 (SG:51) by Materials Project

    SciTech Connect (OSTI)

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  2. Electric field effects in graphene/LaAlO{sub 3}/SrTiO{sub 3}...

    Office of Scientific and Technical Information (OSTI)

    exfoliation and transfer from chemical-vapor deposition on ultraflat copper substrates. ... MICROSCOPY; CHEMICAL VAPOR DEPOSITION; COPPER; ELECTRIC FIELDS; ENERGY BEAM DEPOSITION; ...

  3. Role of the Interface on Radiation Damage in the SrTiO3/LaAlO3...

    Office of Scientific and Technical Information (OSTI)

    Authors: Bi, Zhenxing 1 ; Uberuaga, Blas 1 ; Vernon, Lj 1 ; Aguiar, Jeffery 1 ; Fu, Engang 1 ; Zheng, Shijan 1 ; Zhang, Shixiong 1 ; Wang, Yongqiang 1 ; Misra, Amit ...

  4. Morphology and structural development of reduced anatase-TiO{sub 2} by pure Ti powder upon annealing and nitridation: Synthesis of TiO{sub x} and TiO{sub x}N{sub y} powders

    SciTech Connect (OSTI)

    Bolokang, A.S.; Motaung, D.E.

    2015-02-15

    It is well known that nitriding of titanium is suitable for surface coating of biomaterials and in other applications such as anti-reflective coating, while oxygen-rich titanium oxynitride has been applied in thin film resistors and photocatalysis. Thus in this work anatase was reduced with pure titanium powder during annealing in argon. This was done to avoid any metallic contamination and unwanted residual metal doping. As a result, interesting and different types of particle morphology were synthesized when the pre-milled elemental anatase and titanium powders were mixed. The formation of metastable face centred cubic and monoclinic titanium monoxide was detected by the X-ray diffraction technique. The phases were confirmed by energy dispersive X-ray spectroscopy analysis. Raman analysis revealed weak intensity peaks for samples annealed in argon as compared to those annealed under nitrogen. - Graphical abstract: Display Omitted - Highlights: • Reaction of TiO{sub 2} and Ti induced metastable FCC and monoclinic TiO{sub x}. • Compositions of mixed powder were prepared from the unmilled and pre-milled powders. • Nitridation of TiO{sub x} yielded TiO{sub x}N{sub y} phase. • Mixed morphology was observed on all three powder samples.

  5. Incorporation of chromium into TiO{sub 2} nanopowders

    SciTech Connect (OSTI)

    Kollbek, Kamila; Sikora, Marcin; Kapusta, Czesław; Szlachetko, Jakub; Radecka, Marta; Lyson-Sypien, Barbara; Zakrzewska, Katarzyna

    2015-04-15

    Highlights: • Nanopowders of TiO{sub 2}:Cr with different amount of Cr dopant were obtained by flame spray synthesis, FSS. • Increase in the optical absorption and a shift of the absorption edge were observed upon Cr doping. • HERFD-XANES measurements indicated that the average valence state of titanium ions was preserved. • Increasing magnetic susceptibility of a paramagnetic character was observed upon Cr doping. - Abstract: The paper reports on the results of a study of optical, electronic and magnetic properties of TiO{sub 2} nanopowders doped with Cr ions. Diffused reflectance spectra reveal an increase in the optical absorption and a shift of the absorption edge towards lower energies upon Cr doping. Direct information on the Ti electronic state and the symmetry of its nearest environment is obtained from XANES Ti K-edge spectra. Magnetic behaviour is probed by means of the temperature dependence of DC magnetic susceptibility. Increasing magnetic susceptibility of a paramagnetic character is observed upon increasing chromium doping. The Curie constant of TiO{sub 2}:10 at.% Cr sample (0.12 emu K/mol Oe) is lower than that expected for Cr{sup 3+} (0.1875 emu K/mol Oe) possibly due to the appearance of Cr{sup 4+} or the presence of the orbital contribution to the magnetic moment.

  6. Development of ODS FeCrAl for compatibility in fusion and fission energy applications

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Pint, Bruce A.; Dryepondt, Sebastien N.; Unocic, Kinga A.; Hoelzer, David T.

    2014-11-15

    In this paper, oxide dispersion strengthened (ODS) FeCrAl alloys with 12–15% Cr are being evaluated for improved compatibility with Pb-Li for a fusion energy application and with high temperature steam for a more accident-tolerant light water reactor fuel cladding application. A 12% Cr content alloy showed low mass losses in static Pb-Li at 700°C, where a LiAlO2 surface oxide formed and inhibited dissolution into the liquid metal. All the evaluated compositions formed a protective scale in steam at 1200°C, which is not possible with ODS FeCr alloys. However, most of the compositions were not protective at 1400°C, which is amore » general and somewhat surprising problem with ODS FeCrAl alloys that is still being studied. More work is needed to optimize the alloy composition, microstructure and oxide dispersion, but initial promising tensile and creep results have been obtained with mixed oxide additions, i.e. Y2O3 with ZrO2, HfO2 or TiO2.« less

  7. Development of ODS FeCrAl for compatibility in fusion and fission energy applications

    SciTech Connect (OSTI)

    Pint, Bruce A.; Dryepondt, Sebastien N.; Unocic, Kinga A.; Hoelzer, David T.

    2014-11-15

    In this paper, oxide dispersion strengthened (ODS) FeCrAl alloys with 12–15% Cr are being evaluated for improved compatibility with Pb-Li for a fusion energy application and with high temperature steam for a more accident-tolerant light water reactor fuel cladding application. A 12% Cr content alloy showed low mass losses in static Pb-Li at 700°C, where a LiAlO2 surface oxide formed and inhibited dissolution into the liquid metal. All the evaluated compositions formed a protective scale in steam at 1200°C, which is not possible with ODS FeCr alloys. However, most of the compositions were not protective at 1400°C, which is a general and somewhat surprising problem with ODS FeCrAl alloys that is still being studied. More work is needed to optimize the alloy composition, microstructure and oxide dispersion, but initial promising tensile and creep results have been obtained with mixed oxide additions, i.e. Y2O3 with ZrO2, HfO2 or TiO2.

  8. Interface-Induced Polarization in SrTiO3-LaCrO3 Superlattices...

    Office of Scientific and Technical Information (OSTI)

    Through x-ray absorption near edge spectroscopy and aberration-corrected scanning transmission electron microscopy we show that the Ti cations are displaced off-center in the TiO6 ...

  9. FIRST-PRINCIPLES PHASE STABILITY IN THE TI-V ALLOY SYSTEM (Journal...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: FIRST-PRINCIPLES PHASE STABILITY IN THE TI-V ALLOY SYSTEM Citation Details In-Document Search Title: FIRST-PRINCIPLES PHASE STABILITY IN THE TI-V ALLOY SYSTEM ...

  10. Local Metal and Deuterium Ordering in the Deuterated ZrTiNi C14...

    Office of Scientific and Technical Information (OSTI)

    Local Metal and Deuterium Ordering in the Deuterated ZrTiNi C14 Laves Phase Citation Details In-Document Search Title: Local Metal and Deuterium Ordering in the Deuterated ZrTiNi ...

  11. Deformation behavior of Nb nanowires in TiNiCu shape memory alloy...

    Office of Scientific and Technical Information (OSTI)

    in TiNiCu shape memory alloy matrix This content will become publicly available on August 18, 2016 Title: Deformation behavior of Nb nanowires in TiNiCu shape memory alloy matrix ...

  12. Electric control of magnetism at the Fe/BaTiO3 interface (Journal...

    Office of Scientific and Technical Information (OSTI)

    Electric control of magnetism at the FeBaTiO3 interface Citation Details In-Document Search Title: Electric control of magnetism at the FeBaTiO3 interface Interfacial ...

  13. High-Ti-concentration aerogels for bright x-ray sources (Technical...

    Office of Scientific and Technical Information (OSTI)

    Ti-concentration aerogels for bright x-ray sources Citation Details In-Document Search Title: High-Ti-concentration aerogels for bright x-ray sources Authors: Perez, F ; Patterson,...

  14. High-Ti-concentration aerogels for bright x-ray sources (Technical...

    Office of Scientific and Technical Information (OSTI)

    Ti-concentration aerogels for bright x-ray sources Citation Details In-Document Search Title: High-Ti-concentration aerogels for bright x-ray sources You are accessing a...

  15. Low temperature fabrication of perovskite solar cells with TiO...

    Office of Scientific and Technical Information (OSTI)

    the perovskite were fabricated from TiOsub 2 nanoparticles with different grain sizes. ... performance of solar cells was improved by combination of two TiOsub 2 nanoparticles. ...

  16. Ti3CrCu4: A possible 2-D ferromagnetic spin fluctuating system...

    Office of Scientific and Technical Information (OSTI)

    Ti3CrCu4: A possible 2-D ferromagnetic spin fluctuating system Title: Ti3CrCu4: A possible ... Country of Publication: United States Language: English Word Cloud More Like This Free ...

  17. Conversion of 1,3-Propylene Glycol on Rutile TiO2(110) (Journal...

    Office of Scientific and Technical Information (OSTI)

    Conversion of 1,3-Propylene Glycol on Rutile TiO2(110) Citation Details In-Document Search Title: Conversion of 1,3-Propylene Glycol on Rutile TiO2(110) The adsorption of...

  18. Electrolyte Gate-Controlled Kondo Effect in SrTiO3 (Journal Article...

    Office of Scientific and Technical Information (OSTI)

    Electrolyte Gate-Controlled Kondo Effect in SrTiO3 Prev Next Title: Electrolyte Gate-Controlled Kondo Effect in SrTiO3 Authors: Lee, Menyoung ; Williams, J. R. ; Zhang, Sipei ...

  19. Electric control of magnetism at the Fe/BaTiO3 interface (Journal...

    Office of Scientific and Technical Information (OSTI)

    Electric control of magnetism at the FeBaTiO3 interface Citation Details In-Document Search Title: Electric control of magnetism at the FeBaTiO3 interface You are accessing a ...

  20. Water adsorption induced in-plane domain switching on BaTiO{sub 3} surface

    SciTech Connect (OSTI)

    Li, X.; Bai, Y.; Su, Y. J.; Wang, B. C.

    2015-09-07

    In this study, the influences of the adsorption of water molecules on the changes in the atomic and electric structures of BaTiO{sub 3} surface were investigated using ab initio calculation. Water molecules are molecularly and dissociatively adsorbed on the BaTiO{sub 3} surface, which makes electrons transfer from water molecules to the BaTiO{sub 3} surface. The redistribution of electrons in the BaTiO{sub 3} surface layers weakens the Ba-O interactions and strengthens the Ti-O interactions, so that the Ti atom shifts in TiO{sub 2} plane, i.e., an in-plane domain switching. The adsorption of water molecules on BaTiO{sub 3} surfaces also results in a reduction in the surface rumpling.

  1. Visible Light Absorption of N-Doped TiO2 Rutile Using (LR/RT...

    Office of Scientific and Technical Information (OSTI)

    N-Doped TiO2 Rutile Using (LRRT)-TDDFT and Active Space EOMCCSD Calculations Citation Details In-Document Search Title: Visible Light Absorption of N-Doped TiO2 Rutile Using ...

  2. April 27, 2015-Special ALS Colloquium

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    April 27, 2015-Special ALS Colloquium April 27, 2015-Special ALS Colloquium Print Wednesday, 22 April 2015 13:19 Special Event on Monday, April 27 @ 12 noon, USB 15-253 X-Ray Microscopy: The First 120 Years Janos Kirz, ALS Abstract Röntgen's great discovery became an instant public sensation. Fascination with the "new kind of rays" that could reveal the structure of opaque objects swept the world in 1896. Fifty years later it was widely recognized that the short wavelength of the

  3. ALS Reveals New State of Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Reveals New State of Matter Print ALS user groups from Princeton and Stanford have been making waves this past year with several high-profile papers and extensive news coverage of their work on a new state of matter embodied by "topological insulators," materials that conduct electricity only on their surfaces. First identified at the ALS in 2007 by a Princeton team led by M. Zahid Hasan, topological insulators have been the subject of intense interest, based on unusual quantum

  4. ALS Reveals New State of Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Reveals New State of Matter Print ALS user groups from Princeton and Stanford have been making waves this past year with several high-profile papers and extensive news coverage of their work on a new state of matter embodied by "topological insulators," materials that conduct electricity only on their surfaces. First identified at the ALS in 2007 by a Princeton team led by M. Zahid Hasan, topological insulators have been the subject of intense interest, based on unusual quantum

  5. Summary Slides of ALS Industry Highlights

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Industry Highlights Print No. Slide Beamline Full Web Highlight ALSNews Volume 19 HP Gains Insight with Innovative ALS Tools 11.0.2, 5.3.2.2 05.11.2016 Vol. 372 18 Collaboration Produces World's Best Metrology Tool 6.1.2 01.27.2016 Vol. 369 17 Takeda Advances Diabetes Research at ALS 5.0.2, 5.0.3 06.02.2015 Vol. 364 16 Metrology for Next-Generation Nanopatterning 7.3.3, 11.0.1 01.28.2015 Vol. 360 15 Caribou Biosciences Has Roots at ALS - 09.24.2014 Vol. 357 13 Lithium-Battery Dendrite Growth: A

  6. ALS Reveals New State of Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Reveals New State of Matter Print ALS user groups from Princeton and Stanford have been making waves this past year with several high-profile papers and extensive news coverage of their work on a new state of matter embodied by "topological insulators," materials that conduct electricity only on their surfaces. First identified at the ALS in 2007 by a Princeton team led by M. Zahid Hasan, topological insulators have been the subject of intense interest, based on unusual quantum

  7. ALS Reveals New State of Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Reveals New State of Matter Print ALS user groups from Princeton and Stanford have been making waves this past year with several high-profile papers and extensive news coverage of their work on a new state of matter embodied by "topological insulators," materials that conduct electricity only on their surfaces. First identified at the ALS in 2007 by a Princeton team led by M. Zahid Hasan, topological insulators have been the subject of intense interest, based on unusual quantum

  8. ALS Reveals New State of Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Reveals New State of Matter Print ALS user groups from Princeton and Stanford have been making waves this past year with several high-profile papers and extensive news coverage of their work on a new state of matter embodied by "topological insulators," materials that conduct electricity only on their surfaces. First identified at the ALS in 2007 by a Princeton team led by M. Zahid Hasan, topological insulators have been the subject of intense interest, based on unusual quantum

  9. ALS Reveals New State of Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Reveals New State of Matter Print ALS user groups from Princeton and Stanford have been making waves this past year with several high-profile papers and extensive news coverage of their work on a new state of matter embodied by "topological insulators," materials that conduct electricity only on their surfaces. First identified at the ALS in 2007 by a Princeton team led by M. Zahid Hasan, topological insulators have been the subject of intense interest, based on unusual quantum

  10. ALS Reveals New State of Matter

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ALS Reveals New State of Matter Print ALS user groups from Princeton and Stanford have been making waves this past year with several high-profile papers and extensive news coverage of their work on a new state of matter embodied by "topological insulators," materials that conduct electricity only on their surfaces. First identified at the ALS in 2007 by a Princeton team led by M. Zahid Hasan, topological insulators have been the subject of intense interest, based on unusual quantum

  11. Coating power RF components with TiN

    SciTech Connect (OSTI)

    Kuchnir, M.; Hahn, E.

    1995-03-01

    A facility for coating RF power components with thin films of Ti and/or TiN has been in operation for some time at Fermilab supporting the Accelerator Division RF development work and the TESLA program. It has been experimentally verified that such coatings improve the performance of these components as far as withstanding higher electric fields. This is attributed to a reduction in the secondary electron emission coefficient of the surfaces when coated with a thin film containing titanium. The purpose of this Technical Memorandum is to describe the facility and the procedure used.

  12. Resonance photoelectron spectroscopy of TiX{sub 2} (X = S, Se, Te) titanium dichalcogenides

    SciTech Connect (OSTI)

    Shkvarin, A. S. Yarmoshenko, Yu. M.; Skorikov, N. A.; Yablonskikh, M. V.; Merentsov, A. I.; Shkvarina, E. G.; Titov, A. N.

    2012-11-15

    The photoelectron valence band spectra of TiS{sub 2}, TiSe{sub 2}, and TiTe{sub 2} dichalcogenides are investigated in the Ti 2p-3d resonance regime. Resonance bands in the vicinity of the Fermi energy are found for TiS{sub 2} and TiTe{sub 2}. The nature of these bands is analyzed based on model calculations of the density of electronic states in TiS{sub 2}, TiSe{sub 2}, and TiTe{sub 2} compounds intercalated by titanium atoms. Analysis of experimental data and their comparison with model calculations showed that these bands have different origins. It is found that the resonance enhancement of an additional band observed in TiS{sub 2} is explained by self-intercalation by titanium during the synthesis of this compound. The resonance enhancement in TiTe{sub 2} is caused by occupation of the 3d band in Ti.

  13. High strength, light weight Ti-Y composites and method of making same

    DOE Patents [OSTI]

    Verhoeven, John D.; Ellis, Timothy W.; Russell, Alan M.; Jones, Lawrence L.

    1993-04-06

    A high strength, light weight "in-situ" Ti-Y composite is produced by deformation processing a cast body having Ti and Y phase components distributed therein. The composite comprises elongated, ribbon-shaped Ti and Y phase components aligned along an axis of the deformed body.

  14. High strength, light weight Ti-Y composites and method of making same

    DOE Patents [OSTI]

    Verhoeven, J.D.; Ellis, T.W.; Russell, A.M.; Jones, L.L.

    1993-04-06

    A high strength, light weight in-situ'' Ti-Y composite is produced by deformation processing a cast body having Ti and Y phase components distributed therein. The composite comprises elongated, ribbon-shaped Ti and Y phase components aligned along an axis of the deformed body.

  15. Summary Slides of ALS Industry Highlights

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Print No. Slide Beamline Full Web Highlight ALSNews Volume 17 Takeda Advances Diabetes Research at ALS 5.0.2, 5.0.3 06.02.2015 Vol. 364 16 Metrology for Next-Generation...

  16. Microsoft Word - Maeder et al.doc

    Office of Scientific and Technical Information (OSTI)

    ... molecular nitrogen (Bomar and Knoll 1985; Lobo and Zinder 1988). 73 They also adapt to ... Syst. Appl. Microbiol. 7: 293-299. 494 Lobo, A.L. and S.H. Zinder. 1988. Diazotrophy and ...

  17. Summary Slides of ALS Science Highlights

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Summary Slides of ALS Science Highlights Print No. Slide ... Vol. 356 294 Graphene's 3D Counterpart 10.0.1 ... 06.27.2007 Vol. 277 142 Laser-Seeded CSR 1.4.3 04.25.2007 ...

  18. ALS History: The First 20 Years

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    History: The First 20 Years Print Below is an interactive timeline covering highlights of the first 20 years of ALS history. By no means exhaustive, it is meant to provide a broad ...

  19. Al Husseini Amelio JV | Open Energy Information

    Open Energy Info (EERE)

    Solar Product: JV company to develop a 1GW solar plant in Jordan and an integrated 200MW thin-film module factory. References: Al-Husseini & Amelio JV1 This article is a stub....

  20. Western Baldwin County, AL Grid Interconnection Project

    SciTech Connect (OSTI)

    Thomas DeBell

    2011-09-30

    The Objective of this Project was to provide an additional supply of electricity to the affected portions of Baldwin County, AL through the purchase, installation, and operation of certain substation equipment.