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Sample records for re-123 coated conductors

  1. Comparison between Bi-2223 tape and RE-123 coated conductor from the view point of current transport properties influencing thermal stability

    NASA Astrophysics Data System (ADS)

    Kiss, Takanobu; Inoue, Masayoshi; Higashikawa, Kohei; Suzuki, Takumi; Lyu, Lin; Takasaki, Ken; Imamura, Kazutaka; Onodera, Yuta; Uetsuhara, Dai; Ibi, Akira; Izumi, Teruo; Kitaguchi, Hitoshi

    2016-12-01

    We have investigated flux flow dissipation in typical two kinds of HTS tapes, i.e., a Bi-2223 multi-filamentary tape and a RE-123 coated conductor (CC) from the view point of heat load under over current conditions. Based on systematic measurements on current-voltage characteristics, the nonlinear flux flow dissipation has been described analytically by taking into account current sharing in metallic sheath or stabilization layer. Flux flow dissipation in the RE-123 CC shows much steeper temperature dependence than that of the Bi-2223 tape. As a result, attainable cooling power becomes smaller in the RE-123 CC in comparison with that of Bi-2223 tape even if the same cooling condition. In other word, acceptable temperature rise in the RE-123 CC is small at over current condition, whereas moderate temperature dependence in the Bi-2223 tape allows stable operation even if the bias current exceeds the critical current. Influence of spatial inhomogeneity in the both HTS tapes has also been investigated. Longitudinal variation of local critical current, Ic, and its statistical behavior have been characterized by use of reel-to-reel scanning Hall probe microscopy. It has been found that the flux flow dissipation is possibly localized more than one order higher than that of the average value due to discrete local Ic drops.

  2. Sample and length-dependent variability of 77 and 4.2 K properties in nominally identical RE123 coated conductors

    NASA Astrophysics Data System (ADS)

    Rossi, L.; Hu, X.; Kametani, F.; Abraimov, D.; Polyanskii, A.; Jaroszynski, J.; Larbalestier, D. C.

    2016-05-01

    We present a broad study by multiple techniques of the critical current and critical current density of a small but representative set of nominally identical commercial RE123 (REBa2Cu3O7-δ , RE = rare Earth, here Y and Gd) coated conductors (CC) recently fabricated by SuperPower Inc. to the same nominal high pinning specification with BaZrO3 and RE2O3 nanoprecipitate pinning centers. With high-field low-temperature applications to magnet technology in mind, we address the nature of their tape-to-tape variations and length-wise I c inhomogeneities by measurements on a scale of about 2 cm rather than the 5 m scale normally supplied by the vendor and address the question of whether these variations have their origin in cross-sectional or in vortex pinning variations. Our principal method has been a continuous measurement transport critical current tool (YateStar) that applies about 0.5 T perpendicular and parallel to the tape at 77 K, thus allowing variations of c-axis and ab-plane properties to be clearly distinguished in the temperature and field regime where strong pinning defects are obvious. We also find such in-field measurements at 77 K to be more valuable in predicting 4.2 K, high-field properties than self-field, 77 K properties because the pinning centers controlling 77 K performance play a decisive role in introducing point defects that also add strongly to J c at 4.2 K. We find that the dominant source of I c variation is due to pinning center fluctuations that control J c, rather than to production defects that locally reduce the active cross-section. Given the 5-10 nm scale of these pinning centers, it appears that the route to greater I c homogeneity is through more stringent control of the REBCO growth conditions in these Zr-doped coated conductors.

  3. YBCO COATED CONDUCTORS

    SciTech Connect

    Paranthaman, Mariappan Parans

    2010-01-01

    carefully aligning the grains in YBCO films, low angle boundaries between superconducting YBCO grains allow more current to flow. In fact below a critical misalignment angle of 4 , the critical current density approaches that of YBCO films grown on single crystal substrates [10]. Typically, 2G HTS wires have three components, flexible metal substrate, buffer layers, and REBa2Cu3O7- (REBCO: RE = Rare Earth) superconductor layers [1-7]. Several methods were developed to obtain biaxially textured templates suitable for fabricating high-performance YBCO coated conductors. They are Ion-Beam Assisted Deposition (IBAD), Rolling-Assisted Biaxially Textured Substrates (RABiTS) and Inclined-Substrate Deposition (ISD). Compared to 1G wire, for producing 2G wires using RABiTS or IBAD process, silver is replaced by a low cost nickel alloy, which allows for fabrication of less expensive HTS wires.

  4. High Critical Current Coated Conductors

    SciTech Connect

    Paranthaman, M. P.; Selvamanickam, V.

    2011-12-27

    One of the important critical needs that came out of the DOE’s coated conductor workshop was to develop a high throughput and economic deposition process for YBCO. Metal-organic chemical vapor deposition (MOCVD) technique, the most critical steps in high technical micro fabrications, has been widely employed in semiconductor industry for various thin film growth. SuperPower has demonstrated that (Y,Gd)BCO films can be deposited rapid with world record performance. In addition to high critical current density with increased film thickness, flux pinning properties of REBCO films needs to be improved to meet the DOE requirements for various electric-power equipments. We have shown that doping with Zr can result in BZO nanocolumns, but at substantially reduced deposition rate. The primary purpose of this subtask is to develop high current density MOCVD-REBCO coated conductors based on the ion-beam assisted (IBAD)-MgO deposition process. Another purpose of this subtask is to investigate HTS conductor design optimization (maximize Je) with emphasis on stability and protection issues, and ac loss for REBCO coated conductors.

  5. Strain-controlled critical temperature in REBa2Cu3Oy-coated conductors

    PubMed Central

    Awaji, Satoshi; Suzuki, Takumi; Oguro, Hidetoshi; Watanabe, Kazuo; Matsumoto, Kaname

    2015-01-01

    Recently, we succeeded in detwinning REBa2Cu3O7 (RE123, RE = rare-earth elements)-coated conductors by annealing under an external uniaxial strain. Using the untwinned RE123 tapes, the uniaxial-strain dependencies of the critical temperature Tc along the a and b crystal axes were investigated over a wide strain region from compression to tension. We found that the strain dependencies of Tc for the a and b axes obey a power law but exhibit opposite slopes. In particular, the maximum value of Tc is obtained when the CuO2 plane becomes a square, and its lattice constant is close to 0.385 nm. It is suggested that a tetragonal structure with a ≈ 0.385 nm is the optimum condition for a high critical temperature in high-Tc cuprates. PMID:26063123

  6. Activity in SRL Nagoya Coated Conductor Center for YBCO Coated Conductor by IBAD+ PLD Method -Long, high Ic conductor and a new bamboo-like nanostructure for efficient pinning

    SciTech Connect

    Yamada, Yutaka; Ibi, Akira; Fukushima, Hiroyuki; Kuriki, Reiji; Takahashi, Kazuhiro; Kobayashi, Hiroyoshi; Ishida, Satoru; Konishi, Masaya; Miyata, Seiki; Watanabe, Tomonori; Kato, Takeharu; Hirayama, Tsukasa; Shiohara, Yuh

    2006-03-31

    In SRL-Nagoya Coated Conductor Center (NCCC), long buffered substrate tapes and YBCO coated conductors have been successfully fabricated by using ion-beam assisted deposition (IBAD) and pulsed laser deposition (PLD) methods. For the buffered tape, the PLD-CeO2 method, what we call the 'Self-Epitaxial' method, realized the high degree of in-plane texturing around 4 degrees along the length of 220 m. For YBCO deposition, we have recently introduced new reel-to-reel PLD equipment with a multi-plume and multi-turn deposition system (MPMT PLD). This system succeeded in fabricating a long coated conductor with a high critical current, Ic, of 245 A and length of 212 m. Ic xL (length) reached the world record of 51940 Am. Furthermore, the introduction of artificial pinning center and RE 123 materials were also studied for improving flux pinning and enhancing Ic. A new columnar structure of the 'bamboo structure' (BaZrO3/Y123 layer-stacked structure) was found in Y123+YSZ sample. This columnar structure and the stacking faults in Gd123 were found to be effective for enhancing pinning properties. Using these techniques, we have succeeded in increasing Ic at 0 T to 480 A/cm and also enhancing Ic in a magnetic field.

  7. Oxygen order control by post-annealing for optimizing critical temperature of YBaCuO coated conductors with silver protective layer

    NASA Astrophysics Data System (ADS)

    Jian, Hongbin; Zhong, Huaxiao; Liu, Xumin; Liu, Zhiyong; Bai, Chuanyi; Lu, Yuming; Guo, Yanqun; Boubeche, Mebrouka; Fang, Qiang; Zhang, Hang; Cai, Chuanbing

    2017-07-01

    Oxygenation is one of the most essential processes for practical applications of REBa2Cu3O7-δ (RE123, RE = Y, Gd etc. rare earths) superconductors. Second generation high-Tc superconducting coated conductors are based on biaxial textured RE123 thin films, on which, a cover layer of silver for protecting is normally applied. It results in a little more complicated oxygenation process compared to naked film without silver protective layer. In the present work, a series of absorbing oxygen post-annealing processes were carried out for YBa2Cu3O7-δ coated conductors. The oxygen diffusion procedure and the kinetics in the annealing process were investigated. Analysis and calculations show that the activation energy was 1.01 eV, consistent with previous reports. Moreover, experiments show that the ;over-doping; phenomena frequently occurs in coated conductors, and thus dropping the Tc to as low as 86-88 K. To improve the temperature margin for practical applications (temperature difference between the superconducting transition temperature Tc and application temperature), we investigated the potential of increase in Tc by preventing from the ;over-doped; happening, while keeping oxygen in order. Finally, by employing the new annealing process, we can produce long (several hundred meters) coated conductor with high Tc,onset (92 K), narrow transition width and stable performance.

  8. Percolation analysis of the effect of tape length on the critical current density of 123 coated conductors

    NASA Astrophysics Data System (ADS)

    Nakamura, Yuichi; Izumi, Teruo; Shiohara, Yuh

    2001-07-01

    Although the RE123 coated conductors substantially consist of highly bi-axially aligned polycrystalline RE123 superconductors, the supercurrent must flow through grain boundaries with some angles of misorientation. To investigate the effects of tape length and number of grains in width on the critical current density (Jc), percolation analysis was performed considering the Jc reduction due to misorientation at grain boundaries. The calculation results suggested that the normalized critical current density increased as increasing the number of grains in width and decreased as increasing the tape length. The degree of Jc reduction as increasing the tape length became smaller as increasing the number of grains in width. The calculation results showed that the Jc value of 1 km tape conductor with misorientation full width half maximum /(FWHM)=9° was possibly kept more than 44% of the intragrain Jc when the grain number in width was more than 100 with the grain size of 100 /μm. The tendency of the calculation results of length and FWHM dependence on Jc agreed well with the experimentally obtained length dependence on Jc values of ion-beam assisted deposition conductors.

  9. Percolation analysis of the effect of tape length on the critical current density of 123 coated conductors

    NASA Astrophysics Data System (ADS)

    Nakamura, Yuichi; Izumi, Teruo; Shiohara, Yuh

    2002-07-01

    Although the RE123 coated conductors substantially consist of highly bi-axially aligned polycrystalline RE123 superconductors, the supercurrent must flow through grain boundaries with some angles of misorientation. To investigate the effects of tape length and number of grains in width on the critical current density ( Jc), percolation analysis was performed considering the Jc reduction due to misorientation at grain boundaries. The calculation results suggested that the normalized critical current density increased as increasing the number of grains in width and decreased as increasing the tape length. The degree of Jc reduction as increasing the tape length became smaller as increasing the number of grains in width. The calculation results showed that the Jc value of 1 km tape conductor with misorientation full width half maximum (FWHM)=9° was possibly kept more than 44% of the intragrain Jc when the grain number in width was more than 100 with the grain size of 100 μm. The tendency of the calculation results of length and FWHM dependence on Jc agreed well with the experimentally obtained length dependence on Jc values of ion-beam assisted deposition conductors.

  10. Resistive coating for current conductors in cryogenic applications

    DOEpatents

    Hirayama, Chikara; Wagner, George R.

    1982-05-18

    This invention relates to a resistive or semiconducting coating for use on current conductors in cryogenic applications. This includes copper-clad superconductor wire, copper wire used for stabilizing superconductor magnets, and for hyperconductors. The coating is a film of cuprous sulfide (Cu.sub.2 S) that has been found not to degrade the properties of the conductors. It is very adherent to the respective conductors and satisfies the mechanical, thermal and electrical requirements of coatings for the conductors.

  11. EDITORIAL: Coated conductors and their applications Coated conductors and their applications

    NASA Astrophysics Data System (ADS)

    Freyhardt, Herbert C.; Lee, Dominic; Izumi, Teruo

    2010-01-01

    The attractive perspectives offered by coated conductors, known as the 2nd generation of high temperature superconductors (2G-HTS), have triggered broad and fruitful R&D efforts to make them ready for the marketplace. The anisotropic features of YBCO and its weak-link behavior require the processing of almost single crystalline thin films into flat tapes of coated conductors by basically two different methods: RABiTS—rolling-assisted biaxially textured substrates; and IBAD—ion-beam assisted deposition. Reliable processing technologies are now at hand, and critical current carrying capacities can be raised to almost 10-20% of the theoretically possible limit by optimizing current transfer through grain boundaries as well as flux pinning through control and design of the microstructural landscapes. The optimization of the in-field properties of the 2G-HTS wires, as well as the manufacturing of coated conductors with low ac losses and of assembled conductors for high current application remain active development areas. Cost reduction and more economic processing are still an issue. However, coated conductors are now beginning to penetrate the market, particularly for power and electrical applications, where savings in energy are essential and where the unique features of high temperature superconducting materials can be utilized. Major international conferences have followed up the progress in this exciting realm, and important workshops and discussion meetings have been held on this topic. Nonetheless, it was felt that a concise and up-to-date issue of Superconductor Science and Technology would be most welcome to summarize and collect the latest developments in processing and characterizing coated conductors, as well as drawing attention to the most innovative applications. The Guest Editors of this focus issue owe great thanks to those colleagues who were willing to contribute with their most recent findings to this issue on 'Coated conductors and their

  12. Conversion of Oxyfluoride Based Coated Conductors

    SciTech Connect

    Dan Wesolowski

    2006-11-01

    Direct measurements of HF pressure in equilibrium with the film during the BaF2 process are sorely needed. It is the HF partial pressure that governs the rate at which the film composition is changing and is, therefore, an important factor in controlling the composition/time trajectory of the film. Establishing the composition/time trajectory of both MOD-derived and e-beam derived films for a given set of conditions is another goal for the project. These studies will provide a fundamental understanding of the ex situ process for producing coated conductors.

  13. Coated conductors for power applications: materials challenges

    NASA Astrophysics Data System (ADS)

    Obradors, Xavier; Puig, Teresa

    2014-04-01

    This manuscript reports on the recent progress and the remaining materials challenges in the development of coated conductors (CCs) for power applications and magnets, with a particular emphasis on the different initiatives being active at present in Europe. We first summarize the scientific and technological scope where CCs have been raised as a complex technology product and then we show that there exists still much room for performance improvement. The objectives and CC architectures being explored in the scope of the European project EUROTAPES are widely described and their potential in generating novel breakthroughs emphasized. The overall goal of this project is to create synergy among academic and industrial partners to go well beyond the state of the art in several scientific issues related to CCs’ enhanced performances and to develop nanoengineered CCs with reduced costs, using high throughput manufacturing processes which incorporate quality control tools and so lead to higher yields. Three general application targets are considered which will require different conductor architectures and performances and so the strategy is to combine vacuum and chemical solution deposition approaches to achieve the targeted goals. A few examples of such approaches are described related to defining new conductor architectures and shapes, as well as vortex pinning enhancement through novel paths towards nanostructure generation. Particular emphasis is made on solution chemistry approaches. We also describe the efforts being made in transforming the CCs into assembled conductors and cables which achieve appealing mechanical and electromagnetic performances for power systems. Finally, we briefly mention some outstanding superconducting power application projects being active at present, in Europe and worldwide, to exemplify the strong advances in reaching the demands to integrate them in a new electrical engineering paradigm.

  14. Maximum permissible voltage of YBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Wen, J.; Lin, B.; Sheng, J.; Xu, J.; Jin, Z.; Hong, Z.; Wang, D.; Zhou, H.; Shen, X.; Shen, C.

    2014-06-01

    Superconducting fault current limiter (SFCL) could reduce short circuit currents in electrical power system. One of the most important thing in developing SFCL is to find out the maximum permissible voltage of each limiting element. The maximum permissible voltage is defined as the maximum voltage per unit length at which the YBCO coated conductors (CC) do not suffer from critical current (Ic) degradation or burnout. In this research, the time of quenching process is changed and voltage is raised until the Ic degradation or burnout happens. YBCO coated conductors test in the experiment are from American superconductor (AMSC) and Shanghai Jiao Tong University (SJTU). Along with the quenching duration increasing, the maximum permissible voltage of CC decreases. When quenching duration is 100 ms, the maximum permissible of SJTU CC, 12 mm AMSC CC and 4 mm AMSC CC are 0.72 V/cm, 0.52 V/cm and 1.2 V/cm respectively. Based on the results of samples, the whole length of CCs used in the design of a SFCL can be determined.

  15. Preparation of nickel substrates for coated conductors.

    SciTech Connect

    Truchan, T. G.; Rountree, F. H.; Lanagan, M. T.; McClellan, S. M.; Miller, D. J.; Goretta, K. C.; Tomsic, M.; Foley, R.

    2000-11-01

    Polycrystalline Ni has been used as a substrate for high-current, coated YBa{sub 2}Cu{sub 3}O{sub x} superconductors. For many conductors, Ni is rolled to large deformation and annealed to produce a cube texture. In this study, Ni was rolled to >95% reduction and annealed in 5% H{sub 2}/95% He at 300-1000 C for various times. The resulting substrates were examined by scanning electron microscopy, X-ray and electron diffraction, and surface interferometry. Key determinations for the Ni were extent of in-plane and out-of-plane texture, surface smoothness, and grain size. The extent of texture was approximately independent of annealing temperature and increased slightly with annealing time. Annealing at temperatures >600 C increased surface roughness, primarily due to grain-boundary grooving. Grain growth was fastest at 1000 C and was proportional to time to the 0.1 power.

  16. Fabrication of Filamentary YBCO Coated Conductor by Inkjet Printing

    SciTech Connect

    List III, Frederick Alyious; Kodenkandath, Thomas; Rupich, Marty

    2007-01-01

    Inkjet printing is a potentially low cost, high rate method for depositing precursors for filamentary YBCO coated conductors. The method offers considerable flexibility of filament pattern, width, and thickness. Using standard solution precursors and RABiTSTM substrates, the printing, processing, and properties of some inkjet-derived filamentary YBCO coated conductors for Second Generation (2G) wire are demonstrated on a laboratory scale. Some systematic variations of growth rate and critical transport current with filament width are observed and discussed.

  17. Numerical analysis of quench in coated conductors with defects

    NASA Astrophysics Data System (ADS)

    Liu, Wenbin; Yong, Huadong; Zhou, Youhe

    2016-09-01

    When the superconductor is subjected to local thermal perturbations, a large amount of joule heat may be generated in the conductor, which may lead to a quench. In a quench event, a normal zone irreversibly spreads throughout the conductor leading to failure of the superconducting device. In this paper, we will discuss the one-dimensional quench behavior in the coated conductors with internal defects or interface defects. Based on the numerical procedure given in the previous works, the normal zone propagation is studied by using the finite difference method. The numerical results are presented to discuss the normal zone propagation. We consider the effect of internal defect on the nonuniform temperature propagation. For the conductor with interface defects, it can be found that the normal zone propagation velocity is increased by defects.

  18. Improving YBCO Coated Conductors for Applications (Postprint)

    DTIC Science & Technology

    2012-02-01

    Dec 2006. 14. ABSTRACT Superconducting power devices made of high temperature superconductors (HTS) can enable megawatt-class power systems which... superconductors (HTS) can enable megawatt-class power systems which are lighter in weight and smaller in size than their conventional counterparts. The... motors , and transformers are being developed to address these power concerns. HTS conductors make the development of these HTS power devices

  19. Overview of Materials and Power Applications of Coated Conductors Project

    NASA Astrophysics Data System (ADS)

    Shiohara, Yuh; Taneda, Takahiro; Yoshizumi, Masateru

    2012-01-01

    There are high expectations for coated conductors in electric power applications such as superconducting magnetic energy storage (SMES) systems, power cables, and transformers owing to their ability to contribute to stabilizing and increasing the capacity of the electric power supply grid as well as to reducing CO2 emission as a result of their high critical-current characteristics. Research and development has been performed on wires/tapes and electric power devices worldwide. The Materials and Power Applications of Coated Conductors (M-PACC) Project is a five-year national project in Japan started in 2008, supported by the Ministry of Economy, Trade and Industry (METI) and the New Energy and Industrial Technology Development Organization (NEDO), to develop both coated conductors that meet market requirements and basic technologies for the above-mentioned power applications using coated conductors. In this article, research and development results are reviewed and compared with the interim/final targets of the project, and future prospects are discussed.

  20. Transport AC Losses in Striated YBCO Coated Conductors (Postprint)

    DTIC Science & Technology

    2012-02-01

    Introduction The recent development of Y1Ba2Cu3O7-δ (YBCO) coated conductors has made superconducting machines (such as generators and motors ) for high...where Ploss (in watts) is the power loss of the sample at operating temperature To, Tamb is the ambient temperature and η is the efficiency of the...compared with a conventional one. The relative importance of HTS machine efficiency vs the reduction in weight and volume of a superconducting machine

  1. Critical Current in YBCO Coated Conductors in the Presence of a Macroscopic Defect (POSTPRINT)

    DTIC Science & Technology

    2010-03-01

    AFRL-RZ-WP-TP-2010-2084 CRITICAL CURRENT IN YBCO COATED CONDUCTORS IN THE PRESENCE OF A MACROSCOPIC DEFECT (POSTPRINT) Milan Polak and...CRITICAL CURRENT IN YBCO COATED CONDUCTORS IN THE PRESENCE OF A MACROSCOPIC DEFECT (POSTPRINT) 5a. CONTRACT NUMBER In-house 5b. GRANT NUMBER 5c...display, or disclose the work. 14. ABSTRACT We have studied the effects of localized defects in the YBCO coated conductors on the critical current. The

  2. Removal of degradation of the performance of an epoxy impregnated YBCO-coated conductor double pancake coil by using a polyimide-electrodeposited YBCO-coated conductor

    NASA Astrophysics Data System (ADS)

    Yanagisawa, Y.; Sato, K.; Piao, R.; Nakagome, H.; Takematsu, T.; Takao, T.; Kamibayashi, H.; Takahashi, M.; Maeda, H.

    2012-06-01

    Degradation of the epoxy impregnated YBCO coil performance is due to tensile radial stress concentration on the outer edge of the conductor during cool down. This stress acts as a cleavage stress and opens the conductor edge, fracturing the YBCO layer. The fracture propagates to another edge of the conductor, resulting in degradation of the coil performance. Degradation of the epoxy impregnated YBCO coil is eliminated, if we use a polyimide-electrodeposited YBCO-coated conductor: tensile radial stress concentration on the outer edge of the conductor is reduced due to plastic deformation of the ductile polyimide. Polyimide electrodeposition onto the YBCO-coated conductor is reliable, uniform, easy to apply, and can be extended to larger YBCO magnets, removing the risk of coil degradation.

  3. R&D of coated conductors for applications in Japan

    NASA Astrophysics Data System (ADS)

    Izumi, T.; Shiohara, Y.

    2010-11-01

    On the research and development of coated conductors in Japan, the Ic characteristics and the length have been remarkably improved in the national project. Five hundred meter-long tapes with higher Ic values than 300 A/cm-width were realized by the pulsed laser deposition (PLD) and the metal organic deposition using trifluoroacetates (TFA-MOD) processings for the superconducting layer on the IBAD-GZO buffered substrates. In order to realize the low cost by the increasing the production rate of the ion beam assisted deposition (IBAD) layer, the process of IBAD-MgO was developed and a 1000 m-long IBAD buffer tape was fabricated at an extremely high production rate of 1 km/h. On the other hand, the artificial pinning center has been introduced in both PLD and MOD processing. The BaZrO3 nano-rods were aligned along the c-axis of GdBCO superconducting films by the PLD process. The Jc value in the magnetic field parallel to the c-axis was remarkably improved. Additionally, the BaZrO3 nano-particles were uniformly dispersed in YGdBCO films by the TFA-MOD process and the Jc-B-θ property was confirmed to be isotropic. Based on the above-mentioned achievements, the new national project, whose main objective is the development of some electric power applications using a coated conductor, started in 2008. In this project, the improvement of the coated conductor includes the five sub-themes: (1) degradation of tapes, (2) high Ic under magnetic field, (3) low AC loss, (4) high mechanical strength and high Je and (5) low cost and high yield.

  4. Improvement of spatial homogeneity in IBAD based YBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Zulkifli, Z.; Kiss, T.; Inoue, M.; Enpuku, K.; Kashima, N.; Watanabe, T.; Mori, M.; Nagaya, S.; Ibi, A.; Miyata, S.; Yamada, Y.; Shiohara, Y.

    2008-09-01

    Prior to the development of fabrication technique for the chemical vapor deposited (CVD) YBa 2Cu 3O 7-δ coated conductor on a IBAD-Gd 2Zr 2O 7, investigations on the improvement of spatial homogeneity have been done. By using spatially resolved measurements and combined multiple microanalysis techniques with length scale of several μm, physical and transport properties of the CVD samples have been investigated before and after fabrication modification. Structural inhomogeneity was visualized using thermoelectric voltage imaging (TVI) technique using a laser scanning microscope. Laser scanning microscopy at superconducting temperature is used to visualize flux flow dissipation; furthermore, mappings of 2D local current flow density distribution have been done using a scanning SQUID microscopy. It has been shown that the superconducting layer consisted of YBCO matrix with localized defects originating from the buffer layer. This led to current non-uniformity and caused high flux flow dissipation within the vicinity of the defects. Process conditions have been modified effectively based on those insights. After fabrication modification, our measurement analyses shows that the texturing of the YBCO layer improved significantly and the appearance of spatially distributed obstacles that are responsible for non-uniform current distribution and localized dissipation are reduced. Our complementing, quick yet non-invasive technique not only can quantify the improvement of YBCO homogeneity but also shed light on the basic understanding of the current limiting mechanism in the IBAD based coated conductors.

  5. High current DyBCO-ROEBEL Assembled Coated Conductor (RACC)

    NASA Astrophysics Data System (ADS)

    Goldacker, W.; Nast, R.; Kotzyba, G.; Schlachter, S. I.; Frank, A.; Ringsdorf, B.; Schmidt, C.; Komarek, P.

    2006-06-01

    Low AC loss high transport current HTS cables (>1 kA) are required for application in transformers, generators and are considered for future generations of fusion reactors coils. 2G coated conductors are suitable candidates for high field application at quite high operation temperatures of 50-77 K, which is crucial precondition for economical cooling costs. As a feasibility study we present the first ROEBEL bar cable of approx. 35 cm length made from industrial DyBCO coated conductor (THEVA GmbH, Germany). Meander shaped ROEBEL strands of 4 mm width with a twist pitch of 180 mm were cut from 10 mm wide CC tapes using a specially designed tool. The strands carried in average 157 Amps/cm-width DC and were assembled to a subcable with 5 strands and a final cable with 16 strands. The 5 strand cable was tested and carried a transport current of >300 Amps DC at 77 K, equivalent to the sum of the individual strand transport critical currents. The 16 strand cable carried 500 A limited through heating effects and non sufficient stabilisation and current sharing. A pulse current load indicated a current carrying potential of >1 kA for the 16 strand cable.

  6. Development of HTS power cable using YBCO coated conductor

    NASA Astrophysics Data System (ADS)

    Mukoyama, Shinichi; Yagi, Masashi; Hirano, Hironobu; Yamada, Yutaka; Izumi, Teruo; Shiohara, Yuh

    2006-10-01

    Reductions of AC losses and of cost of HTS power cables are important to put it into practical power networks. Since an YBCO-coated-conductor (YBCO tape) has higher Jc and better magnetic property than a Bi2223-Ag-sheathed-tape, an AC power cable using YBCO tapes will obtain higher performance than XLPE-cables and HTS cables using BSCCO tapes in future. Especially, an YBCO HTS cable will be expected to become a higher economical cable than a Bi cable because an YBCO tape reduced its AC losses and its wire cost. We have started developing HTS power cables using YBCO tapes. Mechanical properties, superconducting properties and other electro magnetic properties of YBCO tapes have been measured to estimate the applicability to the HTS cable. Moreover, we have developed some technologies to bring out latent potentials of YBCO tapes.

  7. Solderability Study of RABiTS-Based YBCO Coated Conductors

    SciTech Connect

    Zhang, Yifei; Duckworth, Robert C; Ha, Tam T; Gouge, Michael J

    2011-01-01

    The solderability of commercially available YBa{sub 2}Cu{sub 3}O{sub 7-x} (YBCO) coated conductors that were made from Rolling Assisted Biaxially Textured Substrates (RABiTS)-based templates was studied. The coated conductors, also known as second-generation (2G) high temperature superconductor (HTS) wires (in the geometry of flat tapes about 4 mm wide), were laminated with copper, brass, or stainless steel strips as stabilizers. To understand the factors that influence their solderability, surface profilometry and scanning electron microscopy were used to characterize the wire surfaces. The solderability of three solders, 52In48Sn, 67Bi33In, and 100In (wt.%), was evaluated using a standard test (IPC/ECA J-STD-002) and with two different commercial fluxes. It was found that the solderability varied with the solder and flux but the three different wires showed similar solderability for a fixed combination of solder and flux. Solder joints of the 2G wires were fabricated using the tools and the procedures recommended by the HTS wire manufacturer. The solder joints were made in a lap-joint geometry and with the superconducting sides of the two wires face-to-face. The electrical resistances of the solder joints were measured at 77 K, and the results were analyzed to qualify the soldering materials and evaluate the soldering process. It was concluded that although the selection of soldering materials affected the resistance of a solder joint, the resistivity of the stabilizer was the dominant factor.

  8. Stability and Normal Zone Propagation Speed in YBCO Coated Conductors with Increased Interfacial Resistance (PREPRINT)

    DTIC Science & Technology

    2010-03-01

    AFRL-RZ-WP-TP-2010-2085 STABILITY AND NORMAL ZONE PROPAGATION SPEED IN YBCO COATED CONDUCTORS WITH INCREASED INTERFACIAL RESISTANCE...August 2006 – 25 August 2008 4. TITLE AND SUBTITLE STABILITY AND NORMAL ZONE PROPAGATION SPEED IN YBCO COATED CONDUCTORS WITH INCREASED INTERFACIAL...reproduce, release, perform, display, or disclose the work. 14. ABSTRACT We will discuss how stability and speed of normal zone propagation in YBCO

  9. Interface morphological stability of unidirectionally solidified RE123 superconductor

    SciTech Connect

    Sumida, M.; Umeda, T.; Shiohara, Y.

    1998-12-31

    A simple model is proposed to analyze the interface stability of the RE123 superconductor in accordance with the constitutional supercooling criterion. As the single crystal growth of the 123 phase is largely dependent on the growth interface stability, a quantitative analysis has been required. From the numerical analysis for the case of peritectically solidified Sm123, it was clarified that the constitutional supercooling must exist in the liquid when the 123 growth interface comes close to a 211 particle. It could also predict that larger 211 particle radius, smaller volume fraction of the 211 particles, larger growth rate, or smaller imposed temperature gradient cause easy occurrence of the constitutional supercooling. The growth rate and a 211 particle radius are determining parameters. Further consideration of the nucleation at the L/211 interface just ahead of the 123 growth front could describe the 123 growth morphological transition from the planar interface to the equiaxed blocky.

  10. High Jc coated conductors with a simple buffer layer architecture

    NASA Astrophysics Data System (ADS)

    Gianni, L.; Baldini, A.; Bindi, M.; Gauzzi, A.; Rampino, S.; Zannella, S.

    2005-10-01

    We report on the in situ route for the continuous fabrication of YBCO coated conductors (CC) by thermal co-evaporation. CC architecture consists of YBCO film grown on biaxially textured Ni-alloys tapes buffered with a single layer of CeO2. The buffer layer deposition has been optimized by either e-beam or thermal evaporation using respectively ceria or metallic cerium. Best results have been obtained on CeO2 film, with a thickness less or equal than 100 nm, grown in a reducing atmosphere at 690 °C with a growth rate of 2.4 Å/s. The optimal samples exhibit a highly biaxial texture, as indicated by FWHM values in the range of 5-8° and 4-6° for respectively in- and out-of-plane orientations. The layers are characterized by an uniform and crack-free surface with an average roughness lower than 10 nm. SIMS analysis confirms the effectiveness of CeO2 buffer layer against Ni interdiffusion. This template allows to obtain YBCO films strong textured, with good superconductive properties. YBCO texture data are equivalent the CeO2 ones. Midpoint critical temperature, Tc, falls reproducibly in 87-88 K range, with transition widths ΔTc < 2-3 K. Critical current density, Jc, up to 2 MA/cm2 at 77 K in self-field, have been achieved in a meter long CC corresponding to Ic/width value of 130 A/cm-width. Uniformity and reproducibility of long CC properties are under optimization.

  11. Influence of substrate magnetism of coated conductors on critical current distribution measurement using magnetic knife method

    NASA Astrophysics Data System (ADS)

    Jiang, Z.; Amemiya, N.; Onuma, T.; Kato, T.; Ueyama, M.; Kashima, N.; Nagaya, S.; Shiohara, Y.

    2008-09-01

    A YBCO coated conductor with non-magnetic substrate and a magnetic Ni alloy tape were prepared to investigate the influence of the substrate magnetism on the Jc distribution measurement. We measured the Jc distribution of the YBCO coated conductor and that of the same YBCO coated conductor with the magnetic tape over-lied on its face (the space between the superconducting layer and the magnetic tape is 20 μm which is the thickness of protecting Ag layer), and compared the measured results with each other. The measured results agreed well with each other, and there was little influence of the tape magnetism on the Jc distribution measurement. Based on this fact, the Jc distribution in a HoBCO coated conductor with magnetic substrate was measured using the magnetic knife method. Twenty-two voltage taps were attached to the conductor with 5 mm separation along the conductor axis. The lateral Jc distributions in the sections were generally in the shape of trapezoid.

  12. Development of Low AC Loss TFA-MOD Coated Conductors

    NASA Astrophysics Data System (ADS)

    Katayama, K.; Machi, T.; Nakamura, T.; Takagi, Y.; Nakaoka, K.; Yoshizumi, M.; Izumi, T.; Shiohara, Y.

    TFA-MOD process is expected to be promising for future applications since it can produce high performance YBCO coated conductors (CCs) with low cost. Applying YBCO CCs to the power electric devices such as transformers and power cables, the reduction of alternating current (AC) loss for long wire is necessary. Multi-filamentation process, which is one of the most effective approaches for AC loss reduction, has been developed by the scribing process. We have developed the filamentation process using chemical etching. MOD derived CCs are, however, easily damaged in the chemical etching process due to existence of pores in a YBCO layer, resulting in critical current (Ic)-degradation and weak delamination strength. Consequently, it is difficult to scribe MOD derived CCs into 1mm-wide filaments for long length using the chemical etching process. Accordingly, we have studied a scribing process using an excimer laser without chemical etching. We defined P' value in this study as a function of irradiated laser power [J] divided by processing speed[m/s]. We studied relationship between the P' value and the results of scribing. It was found that we could scribe the C.C. with a sufficient depth in the condition of large P' value. Furthermore, we found that the Ic was degraded with further increase of the P' value. A 5 mm wide short sample was divided into 10 filaments by the excimer laser scribing process at the P' of 9[J/(m/s)]. The sample revealed reduction of the hysteresis loss down to 1/10 which could be expected from a theoretical prediction using the numbers of the filaments. Ic-degradation was suppressed as 28%, which was smaller than that of the scribed sample using chemical etching (Ic degradation was 38%). Subsequently, we applied the technique to a 100m long YBCO CC. The hysteresis loss of the 100m long MOD derived CC was reduced down to 1/10 (1/the number of filaments) after the multi-filamentation.

  13. Modelling ac ripple currents in HTS coated conductors

    NASA Astrophysics Data System (ADS)

    Xu, Zhihan; Grilli, Francesco

    2015-10-01

    Dc transmission using high temperature superconducting (HTS) coated conductors (CCs) offers a promising solution to the globally growing demand for effective, reliable and economic transmission of green energy up to the gigawatt level over very long distances. The credible estimation of the losses and thereby the heat dissipation involved, where ac ripples (introduced in rectification/ac-dc conversion) are viewed as a potential source of notable contribution, is highly essential for the rational design of practical HTS dc transmission cables and corresponding cryogenic systems to fulfil this demand. Here we report a targeted modelling study into the ac losses in a HTS CC subject to dc and ac ripple currents simultaneously, by solving Maxwell’s equations using the finite element method (FEM) in the commercial software package COMSOL. It is observed that the instantaneous loss exhibits only one peak per cycle in the HTS CC subject to sinusoidal ripples, given that the amplitude of the ac ripples is smaller than approximately 20% of that of the dc current. This is a distinct contrast to the usual observation of two peaks per cycle in a HTS CC subject to ac currents only. The unique mechanism is also revealed, which is directly associated with the finding that, around any local minima of the applied ac ripples, the critical state of -J c is never reached at the edges of the HTS CC, as it should be according to the Bean model. When running further into the longer term, it is discovered that the ac ripple loss of the HTS CC in full-wave rectification decays monotonically, at a speed which is found to be insensitive to the frequency of the applied ripples within our targeted situations, to a relatively low level of approximately 1.38 × 10-4 W m-1 in around 1.7 s. Comparison between this level and other typical loss contributions in a HTS dc cable implies that ac ripple currents in HTS CCs should only be considered as a minor source of dissipation in superconducting dc

  14. Measurement Of Transverse Jc Profiles Of Coated Conductors Using A Magnetic Knife Of Permanent Magnets

    SciTech Connect

    Hanisch, J; Mueller, F M; Ashworth, S P; Coulter, J Y; Matias, Vlad

    2008-01-01

    The transverse J{sub c} distribution in YBCO coated conductors was measured nondestructively with high resolution using a 'magnetic knife' made of permanent magnets. The method utilizes the strong depression of J{sub c} in applied magnetic fields. A narrow region of low (including zero) magnetic field, in a surrounding higher field, is moved transversely across the sample in order to reveal the critical-current density distribution. The net resolution of this device is approximately 65 {mu}m, and the J{sub c} resolution is better than 0.5%. A Fourier series inversion process was used to determine the transverse J{sub c} distribution in the sample. The J{sub c} profile was correlated with other sample properties of coated conductors prepared by pulsed laser deposition. Because of its straight-forward and inexpensive design, this J{sub c} imaging technique can be a powerful tool for quality control in coated-conductor production.

  15. Remarkable weakness against cleavage stress for YBCO-coated conductors and its effect on the YBCO coil performance

    NASA Astrophysics Data System (ADS)

    Yanagisawa, Y.; Nakagome, H.; Takematsu, T.; Takao, T.; Sato, N.; Takahashi, M.; Maeda, H.

    2011-08-01

    Cleavage strength for an YBCO-coated conductor at 77 K was investigated with a model experiment. The nominal cleavage strength for an YBCO-coated conductor is extremely low, typically 0.5 MPa. This low nominal cleavage strength is due to stress concentration on a small part of the YBCO-coated conductor in cleavage fracture. Debonding by the cleavage stress occurs at the interface between the buffer layer and the Hastelloy substrate. The nominal cleavage strength for a slit edge of the conductor is 2.5-times lower than that for the original edge of the conductor; cracks and micro-peel existing over the slit edge reduce the cleavage strength for the slit edge. Cleavage stress and peel stress should be avoided in coil winding, as they easily delaminate the YBCO-coated conductor, resulting in substantial degradation of coil performance. These problems are especially important for epoxy impregnated YBCO-coated conductor coils. It appears that effect of cleavage stress and peel stress are mostly negligible for paraffin impregnated YBCO-coated conductor coils or dry wound YBCO-coated conductor coils.

  16. Test of 60 kA coated conductor cable prototypes for fusion magnets

    NASA Astrophysics Data System (ADS)

    Uglietti, D.; Bykovsky, N.; Sedlak, K.; Stepanov, B.; Wesche, R.; Bruzzone, P.

    2015-12-01

    Coated conductors could be promising materials for the fabrication of the large magnet systems of future fusion devices. Two prototype conductors (flat cables in steel conduits), each about 2 m long, were manufactured using coated conductor tapes (4 mm wide) from Super Power and SuperOx, with a total tape length of 1.6 km. Each flat cable is assembled from 20 strands, each strand consisting of a stack of 16 tapes surrounded by two half circular copper profiles, twisted and soldered. The tapes were measured at 12 T and 4.2 K and the results of the measurements were used for the assessment of the conductor electromagnetic properties at low temperature and high field. The two conductors were assembled together in a sample that was tested in the European Dipole (EDIPO) facility. The current sharing temperatures of the two conductors were measured at background fields from 8 T up to 12 T and for currents from 30 kA up to 70 kA: the measured values are within a few percent of the values expected from the measurements on tapes (short samples). After electromagnetic cycling, T cs at 12 T and 50 kA decreased from about 12 K to 11 K (about 10%), corresponding to less than 3% of I c.

  17. Inkjet printing of multifilamentary YBCO for low AC loss coated conductors

    NASA Astrophysics Data System (ADS)

    Hopkins, S. C.; Joseph, D.; Mitchell-Williams, T. B.; Calleja, A.; Vlad, V. R.; Vilardell, M.; Ricart, S.; Granados, X.; Puig, T.; Obradors, X.; Usoskin, A.; Falter, M.; Bäcker, M.; Glowacki, B. A.

    2014-05-01

    Considerable progress has been made with the development of REBCO coated conductors in recent years, and high performance conductors are available commercially. For many applications, however, the cost remains prohibitive, and AC losses discourage their selection for higher frequency applications. Chemical solution deposition (CSD) methods are attractive for low-cost, scalable preparation of buffer and superconductor layers, and in many respects inkjet printing is the method of choice, permitting non-contact deposition with minimal materials wastage and excellent control of coating thickness. Highly textured coatings of YBCO and Gd-doped CeO2 have previously been reported on buffered metal substrates. Inkjet printing also introduces the possibility of patterning - directly depositing two and three dimensional structures without subtractive processing - offering a low-cost route to coated conductors with reduced AC losses. In this contribution, the inkjet deposition of superconducting YBCO tracks is reported on industrially relevant buffered metal substrates both by direct printing and an inverse patterning approach. In the latter approach, ceria tracks were printed reported, which are a candidate both for resistive filament spacers and buffer layers. TFA-based precursor solutions have been printed on SS/ABAD-YSZ/CeO2 and Ni-W/LZO/CeO2 RABiTS substrates, and the resulting multifilamentary samples characterised by microscopy and scanning Hall probe measurements. The prospects for future inkjet-printed low AC loss coated conductors are discussed, including control of interfilamentary resistivity and bridging, transposed filamentary structures and stabilisation material.

  18. Long length coated conductor fabrication by inclined substrate deposition and evaporation

    NASA Astrophysics Data System (ADS)

    Prusseit, W.; Hoffmann, C.; Nemetschek, R.; Sigl, G.; Handke, J.; Lümkemann, A.; Kinder, H.

    2006-06-01

    The commercial development of coated conductors is rapidly progressing. As a result we present an economic route to produce second generation HTS tape from the initial substrate preparation to the final metal coating. The most important and technically challenging steps are the deposition of an oriented buffer layer and the superconductor film in a reel-to-reel configuration. New evaporation techniques have been developed to enable reliable, high rate tape coating. Highly oriented MgO - buffer layers are realized by inclined substrate deposition (ISD) and DyBCO is deposited by simple e-gun evaporation yielding critical currents beyond 200 A/cm. Coated conductors have been fabricated up to 40 m length and are currently tested in a variety of applications.

  19. The Integration of YBCO Coated Conductors into Magnets and Rotating Machinery (Postprint)

    DTIC Science & Technology

    2012-02-01

    14. ABSTRACT The implementation of the second generation high-Tc superconductors in power applications, such as electrical transformers, motors ...implementation of the 2"d generation high-Tc superconductors in power applications, such as electrical transformers, motors and generators requires...properties of coated conductors manufactured today. 15. SUBJECT TERMS implementation, superconductors , time-varying magnetic field, low bending

  20. Bending properties of different REBCO coated conductor tapes and Roebel cables at T = 77 K

    NASA Astrophysics Data System (ADS)

    Otten, Simon; Kario, Anna; Kling, Andrea; Goldacker, Wilfried

    2016-12-01

    Application of REBCO coated conductors in coils or cables involves deformation of the conductor in different modes, such as in-plane bending, out-of-plane bending and torsion. For example, the dipole magnet designs in the EuCARD-2 project require bending radii as low as 7.5 mm, inducing significant bending strain in the REBCO layer. In this paper, we investigate the effect of out-of-plane bending on the current-carrying properties of coated conductors from different manufacturers. The samples are manipulated by means of a Goldacker-type bending rig, which allows continuous bending at T = 77 K. By reversal to R=∞ after each bending step, the reversible strain effect is separated from irreversible degradation. All tested conductors are found to tolerate compressive bending to a radius of 6 mm with less than 5% irreversible degradation of the critical current. The magnitude of the reversible strain effect shows a large variation among the samples. The effect of out-of-plane bending on Roebel cables is investigated as well, and the results are compared to the bending characteristic of single conductors. The results show no detrimental effect of the cable assembly on the bending properties within the constraints of the test.

  1. Influence of magnetization on field quality in cosine-theta and block design dipole magnets wound with coated conductors

    NASA Astrophysics Data System (ADS)

    Sogabe, Yusuke; Sakashita, Masaki; Nakamura, Taketsune; Ogitsu, Toru; Amemiya, Naoyuki

    2016-04-01

    We carried out electromagnetic field analyses on the cross sections of two dipole magnets wound with coated conductors. One was a cosine-theta magnet, and the other was a block design magnet. The electric field-current density characteristics of the coated conductors were formulated using a percolation depinning model based on the measured voltage-current characteristics. We calculated the temporal evolutions of the current-density distributions in all the turns of each magnet and used these evolutions to calculate the multipole components of the magnetic field. We compared the two magnets, which differed in coated-conductor orientations, regarding the influence of coated-conductor magnetization on the field qualities.

  2. Highly cube textured Cu-based substrates for YBCO-coated conductors

    NASA Astrophysics Data System (ADS)

    Nast, R.; Obst, B.; Goldacker, W.; Holzapfel, B.

    2006-06-01

    Cube textured Cu/Cu-based tapes are shown to be an alternative to Ni/Ni alloy substrates widely used in high current capability YBCO-coated conductors. Copper, other than nickel, is non-magnetic and has a larger thermal and electrical conductivity, keeping up thermal stabilization of the superconductor at cryogenic temperatures. Jointly with the cube texture of exceptional strength that develops after rolling and recrystallization, Cu is, therefore, a candidate material for coated conductor architecture. In this work, we report on the texturing of pure copper and different copper alloys, such as Cu- Mn and a dispersion hardened Cu-B4C tape. For Cu and Cu-B4C, the maximum found in the cube texture histograms are 3.8° and 4.4°, respectively.

  3. Apparatus and method for measuring critical current properties of a coated conductor

    DOEpatents

    Mueller, Fred M [Los Alamos, NM; Haenisch, Jens [Dresden, DE

    2012-07-24

    The transverse critical-current uniformity in a superconducting tape was determined using a magnetic knife apparatus. A critical current I.sub.c distribution and transverse critical current density J.sub.c distribution in YBCO coated conductors was measured nondestructively with high resolution using a magnetic knife apparatus. The method utilizes the strong depression of J.sub.c in applied magnetic fields. A narrow region of low, including zero, magnetic field in a surrounding higher field is moved transversely across a sample of coated conductor. This reveals the critical current density distribution. A Fourier series inversion process was used to determine the transverse J.sub.c distribution in the sample.

  4. Construction and test of a non-insulated insert coil using coated conductor tape

    NASA Astrophysics Data System (ADS)

    Uglietti, D.; Wesche, R.; Bruzzone, P.

    2014-05-01

    A small coated conductor coil (central field 1 T at 200 A) was constructed and tested in order to evaluate the benefit and the possible disadvantages of non insulated, double pancake construction, in particular regarding quench protection. The insert coil consists of three double pancakes without turn to turn insulation, and it was impregnated with beeswax. The coil was equipped with voltage taps on each pancake, thermocouples and a quench heater. Quench tests were carried out because quench protection is one of the main issues in developing coil technology for coated conductors. Quenches were induced either by a heater or by exceeding the coil critical current; in all cases the quench protection system was able to detect the quench.

  5. Development of Nickel Alloy Substrates for Y-Ba-Cu-O Coated Conductor Applications

    DTIC Science & Technology

    2003-10-01

    development of texture in high strength, non-magnetic substrate materials. As the development of cube texture is easier in medium to high stacking fault...superconducting layer, during high temperature processing. Several studies have determined that a sharp, reproducible cube texture can easily develop...become the substrate of choice for coated conductor applications due to ease of achieving sharp cube texture as well as its chemical compatibility

  6. On-Line Texture Diagnostics for Coated Conductor Manufacture. Final Report

    SciTech Connect

    White, M. K.

    2002-12-30

    This Phase I project was undertaken to assess the feasibility of implementing a particular diagnostic method for characterizing the crystallographic texture of high temperature superconductor (HTS) coated conductors on-line during their reel-to-reel continuous manufacture. Key factors in this technique were the use of an area detector to greatly reduce scan time, an x-ray mirror to enhance incident beam brightness, and an automation scheme for diffractometer control, tape motion control, and calculation and output of texture characterizations.

  7. High Upper Critical Field and Irreversibility Field in MgB2 Coated-Conductor Fibers

    DTIC Science & Technology

    2016-06-13

    B. Betts and C. H. Mielke National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 Received 7 September...coated conductors for superconducting magnets . © 2005 American Institute of Physics. DOI: 10.1063/1.2149289 The recently discovered superconductor MgB2...see Ref. 1 is a promising material for high- magnetic -field applications.2 The transition temperature at 40 K allows practical operation above 20 K

  8. Construction and Performance of Small-Sized Coated Conductor Pancake Coils for Surgical Applications

    NASA Astrophysics Data System (ADS)

    Ge, Y.; Lewin, R.; Cahill, R.; Mortensen, N.; Jones, H.

    With a view to applying small-sized superconducting coils for magnetic manipulation in surgery, three pancake coils have been built with commercially available (RE)BCO coated conductor using different impregnation methods and tested in liquid nitrogen and liquid helium. This paper presents the design and construction procedures of these pancake coils and subsequent test results including transport current characteristics in background fields are discussed.

  9. Measurement of transverse Jc profiles of coated conductors using a magnetic knife of permanent magnets

    SciTech Connect

    Haenisch, J; Mueller, F M; Ashworth, S P; Coulter, J Y; Matias, Vlad

    2008-01-01

    The transverse J{sub c} distribution in YBCO coated conductors was measured non-destructively with high resolution using a 'magnetic knife' made of permanent magnets. The method utilizes the strong depression of J{sub c} in applied magnetic fields. A narrow region of low (including zero) magnetic field, in a surrounding higher field, is moved transversely across the sample in order to reveal the critical-current density distribution. The net resolution of this device is approximately 65 {micro}m, and the J{sub c} resolution is better than 0.5%. A Fourier series inversion process was used to determine the transverse J{sub c} distribution in the sample. The J{sub c} profile was correlated with other sample properties of coated conductors prepared by pulsed laser deposition. Because of its straight-forward and inexpensive design, this J{sub c} imaging technique can be a powerful tool for quality control in coated-conductor production.

  10. An efficient 3D finite element method model based on the T-A formulation for superconducting coated conductors

    NASA Astrophysics Data System (ADS)

    Zhang, Huiming; Zhang, Min; Yuan, Weijia

    2017-02-01

    An efficient three dimensional (3D) finite element method numerical model is proposed for superconducting coated conductors. The model is based on the T-A formulation and can be used to tackle 3D computational challenges for superconductors with high aspect ratios. By assuming a sheet approximation for the conductors, the model can speed up the computational process. The model has been validated by established analytical solutions. Two examples with complex geometries, which can hardly be simulated by the 2D model, are given. The model could be used to characterise and design large-scale applications using superconducting coated conductors, such as high field magnets and other electrical devices.

  11. Enhanced low-temperature critical current by reduction of stacking faults in REBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Puichaud, A.-H.; Wimbush, S. C.; Knibbe, R.

    2017-07-01

    The effect of stacking faults (SF) on flux pinning and critical current (I c) in rare earth based coated conductors was investigated. The SF density in YBa2Cu3O7-δ (YBCO) films with and without Dy addition, produced by metal organic deposition, was modified by altering the oxygenation temperature. A detailed microstructural analysis of the coated conductors was performed by x-ray diffraction, scanning and transmission electron microscopy and energy dispersive spectroscopy, and the observed defect population was correlated with both the self-field and in-field I c. We report that the best self-field I c was obtained for samples having a low SF density, in spite of the SF being effective flux pinning defects at 77 K for magnetic fields applied within the ab plane. We also show that the SF have no observable flux pinning effect at low temperatures. This study demonstrates that for devices operated at low temperatures, the elimination of SF in the conductor wires is essential to attain higher I c.

  12. Field and temperature scaling of the critical current density in commercial REBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Senatore, Carmine; Barth, Christian; Bonura, Marco; Kulich, Miloslav; Mondonico, Giorgio

    2016-01-01

    Scaling relations describing the electromagnetic behaviour of coated conductors (CCs) greatly simplify the design of REBCO-based devices. The performance of REBCO CCs is strongly influenced by fabrication route, conductor architecture and materials, and these parameters vary from one manufacturer another. In the present work we have examined the critical surface for the current density, J c(T, B, θ), of coated conductors from six different manufacturers: American Superconductor Co. (US), Bruker HTS GmbH (Germany), Fujikura Ltd (Japan), SuNAM Co. Ltd (Korea), SuperOx ZAO (Russia) and SuperPower Inc. (US). Electrical transport and magnetic measurements were performed at temperatures between 4.2 K and 77 K and in magnetic fields of up to 19 T. Experiments were conducted at three different orientations of the field with respect to the crystallographic c-axis of the REBCO layer, θ = 0°, 45° and 90°, in order to probe the angular anisotropy of J c. In spite of the large variability of the CCs’ performance, we show here that field and temperature dependences of J c at a given angle can be reproduced over wide ranges using a scaling relation based only on three parameters. Furthermore, we present and validate a new approach combining magnetic and transport measurements for the determination of the scaling parameters with minimal experimental effort.

  13. Performance of coils wound from long lengths of surface-coated, reacted, BSCCO-2212 conductor

    SciTech Connect

    Walker, M.S.; Hazelton, D.W.; Gardner, M.T.

    1996-10-01

    React-before-wind surface-coated BSCCO-2212 is being established as a relatively low cost HTS conductor for practical applications. Quality tape is presently being manufactured in 450-500m lengths at a cost estimated to be 1/3-1/5 of the industry costs of BSCCO-2223 powder-in-tube tape. Robust, mechanically sound coils for applications ranging from NMR insert magnets to transformer windings are being made from this BSCCO-2212 tape. The coils have performed consistently through test and thermal cycling without degradation and as projected from short sample measurements. A hybrid approach, which uses mainly BSCCO- 2212 augmented by BSCCO-2223 conductor in the high radial field end regions, is expected to halve magnet system costs.

  14. Interlayer structure in YBCO-coated conductors prepared by chemical solution deposition

    NASA Astrophysics Data System (ADS)

    Molina-Luna, Leopoldo; Egoavil, Ricardo; Turner, Stuart; Thersleff, Thomas; Verbeeck, Jo; Holzapfel, Bernhard; Eibl, Oliver; Van Tendeloo, Gustaaf

    2013-07-01

    The functionality of YBa2Cu3O7-δ (YBCO)-coated conductor technology depends on the reliability and microstructural properties of a given tape or wire architecture. Particularly, the interface to the metal tape is of interest since it determines the adhesion, mechanical stability of the film and thermal contact of the film to the substrate. A trifluoroacetate (TFA)—metal organic deposition (MOD) prepared YBCO film deposited on a chemical solution-derived buffer layer architecture based on CeO2/La2Zr2O7 and grown on a flexible Ni5 at.%W substrate with a {100}<001> biaxial texture was investigated. The YBCO film had a thickness was 440 nm and a jc of 1.02 MA cm-2 was determined at 77 K and zero external field. We present a sub-nanoscale analysis of a fully processed solution-derived YBCO-coated conductor by aberration-corrected scanning transmission electron microscopy (STEM) combined with electron energy-loss spectroscopy (EELS). For the first time, structural and chemical analysis of the valence has been carried out on the sub-nm scale. Intermixing of Ni, La, Ce, O and Ba takes place at these interfaces and gives rise to nanometer-sized interlayers which are a by-product of the sequential annealing process. Two distinct interfacial regions were analyzed in detail: (i) the YBCO/CeO2/La2Zr2O7 region (10 nm interlayer) and (ii) the La2Zr2O7/Ni-5 at.%W substrate interface region (20 nm NiO). This is of particular significance for the functionality of these YBCO-coated conductor architectures grown by chemical solution deposition.

  15. Growth and properties of REBiO 3 new buffer materials for coated conductors

    NASA Astrophysics Data System (ADS)

    Li, G.; Pu, M. H.; Sun, R. P.; Wang, W. T.; Zhang, X.; Zhang, H.; Yang, Y.; Zhang, Y.; Zhang, H.; Cheng, C. H.; Zhao, Y.

    2008-09-01

    A new series of ABO 3-type REBiO 3 have been derived from the system Bi 2O 3-RE 2O 3, in which cubic RE 2O 3 stabilize cubic structure of δ-Bi 2O 3, enabling the formation of REBiO 3 at relatively low temperature range. A chemical solution deposition (CSD) route has been used to deposit epitaxial thin films of REBiO 3. The crystal lattice, chemical stability, texture development, combined with the successful deposition of high quality superconducting layer demonstrate that the newly developed compounds may play as potential alternatives of buffer layer materials for REBCO-based coated conductors.

  16. Development of cube textured Ni-W alloy substrates used for coated conductors

    NASA Astrophysics Data System (ADS)

    Suo, Hongli; Ma, Lin; Gao, Mangmang; Meng, Yichen; Wang, Yi; Liu, Min; Zhao, Yue; Grivel, Jean-Claude

    2014-05-01

    It is considered as a challenge for RABiTS route to get cube textured Ni-W alloy substrates with high mechanical and magnetic properties for coated conductors. The works of our group in recent years are summarized about different Ni-W substrates with high W content and composite tapes made by RABiTS technique. The fabrication process and the mechanism of cube texture formation in above different tapes are studied systematically. Compared with commercial Ni-5 at.%W substrate, these alloy substrates show a comparable texture quality and improved mechanical properties as well as reduced or zero magnetization especially in the novel composite substrates.

  17. Development of Coated Conductors in Japanese National Project "Development of Fundamental Technologies for HTS Coils"

    NASA Astrophysics Data System (ADS)

    Yoshizumi, Masateru; Izumi, Teruo; Shiohara, Yuh

    RE1Ba2Cu3O7-x (REBCO, RE=rare earth) coated conductors have attracted the attention of many scientists due to the high superconducting properties, etc. Due to the great progress of R&D on coated conductors, the activities have shifted to specific applications. The new Japanese national project, named as "Development of Fundamental Technologies for HTS Coils", started last year aiming for the applications of MRI and medical accelerators. To meet the requirements of those applications, the R&D of REBCO coated conductors (CCs) are being performed with that of coiling technology in parallel. The theme has two sub-themes of "development of long CCs with high in-field performance" and "development of CCs with extremely low heat generation" in this national project. The ambitious goals of these themes are set as intermediate ones due 2016 Mar; the theme of in-field: 100m-500A/cm-w@65K, 3T -850A/cm-w@35K, 10T, the theme of low heat generation: 100m-500 μm of filament width w/ Icfilament inhomogeneity of distribution within 10% and joint resistance below 5nΩ. The final goals of these themes due 2018 Mar. were set as follows; the theme of in-field: 200m-600A/cm-w@65K, 3T -1000A/cm-w@35K, 10T, the theme of low heat generation: 200m-500 μm of filament width w/ Icfilament distribution within 5% and joint resistance below 3nΩ. The objectives, goals and progress of this project will be reviewed in this article. As for the progress, for example, the combination of EuBCO+BHO was found to be effective to improve the in-field performance of PLD derived coated conductors. A 94 m long wire with Icmin of 108A/cm-w@77K, 3T (corresponding to 472A/cm-w @65K, 3T) was successfully fabricated. It is as twice Icmin of the long tape as the highest one in the previous project.

  18. Insert Coil Test for HEP High Field Magnets Using YBCO Coated Conductor Tapes

    SciTech Connect

    Lombardo, V.; Barzi, E.; Turrioni, D.; Zlobin, A.V.; /Fermilab

    2011-06-15

    The final beam cooling stages of a Muon Collider may require DC solenoid magnets with magnetic fields of 30-50 T. In this paper we present progress in insert coil development using commercially available YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} Coated Conductor. Technological aspects covered in the development, including coil geometry, insulation, manufacturing process and testing are summarized and discussed. Test results of double pancake coils operated in liquid nitrogen and liquid helium are presented and compared with the performance of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} tape short samples.

  19. Influence of superconductor film composition on adhesion strength of coated conductors

    SciTech Connect

    Kesgin, Ibrahim; Khatri, Narayan; Liu, Yuhao; Delgado, Louis; Galstyan, Eduard; Selvamanickam, Venkat

    2015-11-20

    The effect of high temperature superconductor (HTS) film composition on the adhesion strength of rare- earth barium copper oxide coated conductors (CCs) has been studied. It has been found that the mechanical integrity of the superconductor layer is very susceptible to the defects especially those along the ab plane, probably due to the weak interfaces between the defects and the matrix. Gd and Y in the standard composition were substituted with Sm and the number of in-plane defects was drastically reduced. Consequently, a four-fold increase in adhesion or peeling strength in Sm-based CCs was achieved compared to the standard GdYBCO samples.

  20. High current density electropolishing in the preparation of highly smooth substrate tapes for coated conductors

    DOEpatents

    Kreiskott, Sascha [Los Alamos, NM; Matias, Vladimir [Santa Fe, NM; Arendt, Paul N [Los Alamos, NM; Foltyn, Stephen R [Los Alamos, NM; Bronisz, Lawrence E [Los Alamos, NM

    2009-03-31

    A continuous process of forming a highly smooth surface on a metallic tape by passing a metallic tape having an initial roughness through an acid bath contained within a polishing section of an electropolishing unit over a pre-selected period of time, and, passing a mean surface current density of at least 0.18 amperes per square centimeter through the metallic tape during the period of time the metallic tape is in the acid bath whereby the roughness of the metallic tape is reduced. Such a highly smooth metallic tape can serve as a base substrate in subsequent formation of a superconductive coated conductor.

  1. Coated conductors

    DOEpatents

    Arendt, Paul N.; Foltyn, Stephen R.; Stan, Liliana; Usov, Igor O.; Wang, Haiyan

    2010-06-15

    Articles are provided including a base substrate having a layer of an IBAD oriented material thereon, and, a layer of barium-containing material selected from the group consisting of barium zirconate, barium hafnate, barium titanate, barium strontium titanate, barium dysprosium zirconate, barium neodymium zirconate and barium samarium zirconate, or a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates upon the layer of an IBAD oriented material. Such articles can further include thin films of high temperature superconductive oxides such as YBCO upon the layer of barium-containing material selected from the group consisting of barium zirconate, barium hafnate, barium titanate, barium strontium titanate, barium dysprosium zirconate, barium neodymium zirconate and barium samarium zirconate, or a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates.

  2. Flux pinning study of RE barium coper oxide coated conductors for high field magnet applications

    NASA Astrophysics Data System (ADS)

    Xu, Aixia

    REBa2Cu3O7-δ (REBCO, RE = rare earth) coated conductor (CC) holds great promise for high field magnet applications owing to its strong irreversibility field (Hirr), low electromagnetic anisotropy (γ2), and high critical current density (Jc). The work of this thesis is tightly related to the development of the funded 32 T, all-superconducting magnet project at the NHMFL. My concern is thus for understanding the optimizing of the working parameters of REBCO CC at low temperatures T, and very high magnetic fields H, focusing on how to enhance Ic and to reduce its angular dependence. Increasing the active cross-section is a direct and economical strategy to enhance the current-carrying capability for REBCO coated conductors. Unfortunately, the high Jc in thin REBCO layers is seldom sustained in thick layers because of difficulties of thick film growth control. In the presence of strong 3D (pin separation far less than film thickness) pins, a high and thickness-independent (Jc) should result. One of major tasks of this thesis is to explore what are the effective strong 3D pins that develop a high and thickness-independent Jc. High and weak thickness-dependent Jc at 77 K is obtained on most recent coated conductors, and BZO nanorods and RE2O 3 nanoparticles are identified as strong 3D pins contributing to this respectable Jc performance. At 77 K, we found that the strong pinning of BZO nanorods remains at least up to 9 T, whereas the strong pinning of RE2O3 nanoparticles gradually evolves to weak collective pinning as the irreversibility field is approached. The second principal part of this thesis concentrates on understanding and minimizing the angular dependence of Jc. Our study is based on the following procedure. First, we investigated the angular dependence of Jc (Jc(θ)) in the working condition of the future 32 T all-superconducting magnet, i.e. 4.2 K and high magnetic field up to 31 T. Our work shows that the low temperature Jc(θ) is Ginzburg-Landau-like at

  3. Ac-loss measurement of a DyBCO-Roebel assembled coated conductor cable (RACC)

    NASA Astrophysics Data System (ADS)

    Schuller, S.; Goldacker, W.; Kling, A.; Krempasky, L.; Schmidt, C.

    2007-10-01

    Low ac-loss HTS cables for transport currents well above 1 kA are required for application in transformers and generators and are taken into consideration for future generations of fusion reactor coils. Coated conductors (CC) are suitable candidates for high field application at an operation temperature around 50-77 K, which is a crucial precondition for economical cooling costs. We prepared a short length of a Roebel bar cable made of industrial DyBCO coated conductor (Theva Company, Germany). Meander shaped tapes of 4 mm width with a twist pitch of 122 mm were cut from 10 mm wide CC tapes using a specially designed tool. Eleven of these strands were assembled to a cable. The electrical and mechanical connection of the tapes was achieved using a silver powder filled conductive epoxy resin. Ac-losses of a short sample in an external ac field were measured as a function of frequency and field amplitude in transverse and parallel field orientations. In addition, the coupling current time constant of the sample was directly measured.

  4. Development of buffer layers on 30 mm wide textured metal substrates for REBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Yamaguchi, T.; Ota, H.; Ohki, K.; Konishi, M.; Ohmatsu, K.

    2010-11-01

    We have been studying REBa2Cu3Ox (RE: rare earth elements) coated conductors on clad-type substrates. We developed coated conductors on the 10 mm wide clad-type tape, and succeeded in obtaining the maximum critical current of 380 A/cm with the 2.0 μm thick GdBa2Cu3Ox superconducting film. At present, we are trying to widen the tape width from 10 mm to 30 mm in order to increase production throughput. We report our recent progress on scaling-up of the buffer layers and their properties. The buffer layers consisted of three layers; CeO2 as the seed layer, yttrium-stabilized zirconia (YSZ) as the diffusion barrier layer and CeO2 as the lattice matching layer. They were grown by the RF-sputtering method and the electron beam evaporation technique (EB). EB deposition has possibility of higher throughput compared with the RF-sputtering. The intensity ratio of (2 0 0) to (2 0 0) + (1 1 1) for the lattice matching layer showed as high as 98%. The uniform properties of 40 m long and 30 mm wide substrates were successfully produced by all sputtering method. Additionally, the tape travel speed of the seed layer can be increased from 7 m/h (RF-sputtering deposition) to 10 m/h (EB deposition) on short sample (0.3 m long).

  5. Development of a laser scribing process of coated conductors for the reduction of AC losses

    NASA Astrophysics Data System (ADS)

    Suzuki, K.; Matsuda, J.; Yoshizumi, M.; Izumi, T.; Shiohara, Y.; Iwakuma, M.; Ibi, A.; Miyata, S.; Yamada, Y.

    2007-08-01

    Expectations are high for using coated conductors for electric power applications not only because of better cost performance but also higher Jc-B properties compared with Bi2Sr2Ca2Cu3O10 (BSCCO) tapes. Furthermore, the coated conductors could also reduce AC losses by the use of various methods in post-treatment. When a YAG laser was used for scribing the superconductive layer, an AC loss reduction due to a decrease in the width of the superconductivity layer could be confirmed in short samples. In the case of AC applications using long tapes, high resistance between scribed filaments is necessary. However, the resistance between the filaments scribed by a laser was as low as 10-3 Ω cm-1. The reason for the low resistance was the existence of dross in the filament spacings, which was confirmed by a cross-sectional compositional mapping observation. Although the superconductivity layer was divided by the laser, the dross of the metal substrate made a bridge over the superconductivity filaments. Post-annealing in an O2 atmosphere to oxidize the dross was carried out in order to increase the resistance. Consequently, the resistance between the filaments was improved to be as high as 50 Ω cm-1. We succeeded in controlling the resistance value between filaments in a range five orders of magnitude higher than that of the as-scribed YBCO film, through oxygen atmosphere post-annealing.

  6. Study of Corrosion Resistance Improvement by Metallic Coating for Overhead Transmission Line Conductor

    NASA Astrophysics Data System (ADS)

    Isozaki, Masanori; Adachi, Kouichi; Hita, Takanori; Asano, Yuji

    Applying anti-corrosion grease and aluminum clad steel (AC) wires to ACSR has adopted as general methods to prevent overhead transmission line conductors and/or wires from corrosion. However, there are some cases that ineffectiveness of those means are reported on some transmission lines passing through acid atmosphere in the vicinity of a factory exhausting acid smoke. The feature of the corrosion caused by acid atmosphere is to show a higher speed in its progressing as well known. As means against such acid corrosion, application of high purity aluminum, selective removal of inter-metallic compound in aluminum and plastic coating wires has been reported before, and each has both of advantage and disadvantage actually. In the former letter, we reported the new type of anti-corrosion grease that shows an excellent property against acid atmosphere as well as in a salty circumstance. Here presents a new type of anti-corrosion technology of applying high corrosion resistance aluminum alloy or zinc coatings on each component wires of a conductor that we succeed in developing through a serial study of anti-corrosion methods on overhead transmission lines.

  7. Observation of important current-limiting defects in a recent high pinning force MOCVD IBAD-MgO coated conductor

    NASA Astrophysics Data System (ADS)

    Li, Pei; Abraimov, Dmytro; Xu, Aixia; Larbalestier, David

    2012-02-01

    Optimization of vortex pinning in REBCO coated conductors has been very successful in recent years, but here we report that strong current-limiting effects can still be present in even highly optimized samples. We studied a state-of-the-art MOCVD IBAD-MgO coated conductor, finding it to have a global pinning force Fpmax(77 K, H ∥ c axis) that reached 11 GN m-3. Using low temperature laser scanning microscopy (LTLSM), we found that the local electric field in the flux-flow state was very inhomogeneous and dominated by a high density of a-axis grains, which obstruct current flow on dimensions of several µm. By carefully cutting narrow tracks without such grains in the path, Fpmax rose to 17 GN m-3, a value exceeding all but a very few, carefully made research films. That today’s coated conductors can develop exceptional vortex pinning properties, while still losing a significant fraction of the current density to blocking by growth defects, emphasizes that coated conductor development requires simultaneous attention both to enhancement of vortex pinning and to minimization of current-blocking defects.

  8. Stability measurement of double-side-surface-coated Bi-2212 tape conductors in water environment

    NASA Astrophysics Data System (ADS)

    Zhou, J. P.; McDevitt, J. T.; Hazelton, D. W.

    1999-09-01

    The stability of double-side-coated Bi2Sr2CaCu2O8 (Bi-2212) tapes on Ag substrates in a water environment has been studied. A phase analysis of the as-processed tape conductors was performed and indicated that aqueous precipitates are formed in the tapes exposed to aerated water solution. The nominal composition of the precipitates was found to be Sr1-xCaxCuO2 (xicons/Journals/Common/backsimeq" ALT="backsimeq" ALIGN="TOP"/>0.4). This phase is present in the tapes before the corrosive damage ensues. In order to evaluate the stability properties of the Sr0.6Ca0.4CuO2 phase in a water environment, the pure compound was synthesized and treated under the same conditions as the tapes. Studies reveal that similar corrosion occurs in the Sr0.6Ca0.4CuO2 phase. Thus, the presence of this impurity phase, which appears upon heat treatment of the tape assemblies, is found to be an important factor in the degradation behaviour of the Bi-2212 tape conductors.

  9. Individual grain boundary properties and overall performance of metal-organic deposition coated conductors

    NASA Astrophysics Data System (ADS)

    Weigand, M.; Speller, S. C.; Hughes, G. M.; Rutter, N. A.; Lozano-Perez, S.; Grovenor, C. R. M.; Durrell, J. H.

    2010-05-01

    We have investigated single grain boundaries (GBs) isolated in coated conductors produced by metal-organic deposition. When a magnetic field is swept in the film plane, an angle-dependent crossover from boundary to grain limited critical current density Jc is found. In the force-free orientation, even at fields as high as 8 T, the GBs still limit Jc . We deduce that this effect is a direct consequence of GB meandering. We have employed these single GB results to explain the dependence of Jc of polycrystalline tracks on their width: in-plane measurements become flatter as the tracks are narrowed down. This result is consistent with the stronger GB limitation at field configurations close to force-free found from the isolated boundaries. Our study shows that for certain geometries even at high fields the effect of GBs cannot be neglected.

  10. Powder metallurgy for the fabrication of bi-axially textured Ni tapes for YBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Lee, Dong-Wook; Ki Ji, Bong; Hyung Lim, Jun; Jung, Choong-Hwan; Joo, Jinho; Park, Soon-Dong; Jun, Byung-Hyuk; Hong, Gye-Won; Kim, Chan-Joong

    2003-04-01

    Bi-axially textured Ni tapes for YBCO coated conductors were fabricated by forming, sintering, cold rolling and heat treatment of Ni powder compacts. The powder metallurgy process consists of filling of fine Ni powders in a rubber mold, cold isostatical pressing in a water chamber and sintering of the powder compacts. The sintered compacts were cold-rolled and made into tapes with a thickness of 100 micron and then heat-treated at 1000 °C for various time periods for the development of the (2 0 0) texture. The (2 0 0) texture of Ni tape was successfully formed through the optimization of the recrystallization heat treatment condition for the cold rolled Ni tapes. The full width half maximum of the Ni tapes was 8-10° and the atomic force microscopy surface roughness was 3-5 nm.

  11. Test results of 12/18 kA ReBCO coated conductor current leads

    NASA Astrophysics Data System (ADS)

    Kovalev, I. A.; Surin, M. I.; Naumov, A. V.; Novikov, M. S.; Novikov, S. I.; Ilin, A. A.; Polyakov, A. V.; Scherbakov, V. I.; Shutova, D. I.

    2017-07-01

    A pair of hybrid current leads (brass + stacked & soldered ReBCO tapes) rated for 12 kA in steady state and for up to 18 kA at pulsed over current conditions was designed, developed and tested at NRC ;Kurchatov Institute; (NRC ;KI;). During the experiment at LN2 temperature, the current leads (CLs) were successfully charged with 18 kA at 100 A/s ramp rate. To date, as far as we know, this is the highest current capacity achieved for 2G HTS current leads. The feasibility of ;stack-and-soldering technique; for 10 kA+ class coated conductor CLs for accelerators and fusion was demonstrated. This paper gives an overview of the leads design and presents the preliminary test results. Detailed studies of magnetic properties and current sharing process for the stacked and staggered HTS joints are also reported.

  12. RCS of a coated circular waveguide terminated by a perfect conductor

    NASA Technical Reports Server (NTRS)

    Lee, Choon S.; Lee, Shung-Wu

    1987-01-01

    The radar cross section (RCS) of a circular waveguide terminated by a perfect electric conductor is calculated by the geometrical theory of diffraction for the rim diffraction and by a physical optics approximation for the interior irradiation. The interior irradiation is generally more than 10 dB higher than the rim diffraction for a/lambda equal to or greater than 1 (a is the waveguide radius, lambda is the free-space wavelength). At low frequencies (a/lambda about 1), the interior irradiation can be significantly reduced over a broad range of incident angle if the interior waveguide wall is coated with a thin layer (1 percent of the radius) of lossy magnetic material. Our theoretical prediction is confirmed by measurements. At higher frequencies (a/lambda about 3), a thin layer of coating is effective for the case of near axial incidence, provided that a good transition of the TE(11) mode near the waveguide opening to the HE(11) mode inside the waveguide is made. A thicker layer of coating is required for the RCS reduction over wider incident angle.

  13. Pd layer on cube-textured substrates for MOD-TFA and PLD YBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Mancini, A.; Celentano, G.; Galluzzi, V.; Rufoloni, A.; Vannozzi, A.; Augieri, A.; Ciontea, L.; Petrisor, T.; Gambardella, U.; Longo, G.; Cricenti, A.

    2008-01-01

    Pd films were deposited on rolling assisted biaxially textured substrate (RABiTS) Ni-5 at.% W in order to exploit the Pd effect of the texture sharpening with respect to that of the substrate, for the development of YBa2Cu3O7-x (YBCO) coated conductors. The Pd sharpening effect was relevant in the out-of-plane direction where the reduction for the ω-scans' full width at half maximum (FWHM) ranged from 55 to 65%, depending on the substrate roughness. The obtained minimum values of the FWHM in the transverse rolling direction of the (002) Pd ω-scan and in the (111) Pd phi-scan were of about 2.5° and 5°, respectively. The CeO2/YSZ/CeO2 (YSZ is Y2O3-stabilised ZrO2) heterostructure of the buffer layer was developed by pulsed laser deposition (PLD). In order to transfer the sharp orientation of the Pd film, both the seed CeO2 layer and the YSZ layer were deposited at low temperatures (450 °C), low enough to avoid Pd/Ni-W interdiffusion. The YBCO, films deposited by both PLD and metal-organic deposition (MOD) using metal trifluoroacetate acid (TFA), exhibited rolling direction (005) ω-scan and the (113) phi-scan FWHM values of about 2° and 5°, respectively. In spite of the complete interdiffusion between Ni and Pd during the YBCO film deposition, the coated conductors exhibit good adherence, as well as a smooth and crack-free surface. A zero-resistance critical temperature (TC0) of 90.8 K for the MOD-TFA YBCO films and critical current-density (JC) up to 2.2 MA cm-2 at 77 K and self-field for PLD YBCO films have been obtained.

  14. Cube-textured substrates for YBCO-coated conductors: microstructure evolution and stability

    NASA Astrophysics Data System (ADS)

    Vannozzi, A.; Rufoloni, A.; Celentano, G.; Augieri, A.; Ciontea, L.; Fabbri, F.; Galluzzi, V.; Gambardella, U.; Mancini, A.; Petrisor, T.

    2006-12-01

    The realization of YBCO-based coated conductors with high critical current density involves the deposition of highly biaxially textured YBCO films. The use of epitaxial growth shifts this requirement to the template used for YBCO deposition. In the rolling-assisted biaxially textured substrate (RABiTS) approach, an appropriately oriented template is provided by a cube-textured substrate. The development of a cube texture is the result of recrystallization occurring in a heavily deformed tape, which is activated by high-temperature annealing. In the case of Ni-based alloys, thermal treatment at temperatures ranging from 900 to 1150 °C for at least 30 min is commonly used. The determination of the minimum conditions for thermal treatments in terms of temperature-time involved in the recrystallization process is therefore of practical interest. In this work, Ni-5 at.% W alloy has been studied as a substrate for YBCO-coated conductors. 100 µm thick tapes have been obtained through heavy cold rolling, followed by annealing in high vacuum. Different thermal treatments with rates of 20 °C min-1 have been performed in order to study the formation and the evolution of the cube texture. Moreover, the annealing time has been varied in order to inspect the thermal stability of the substrate microstructure at the relatively high deposition temperature of YBCO films. It is found that the substrate begins recrystallizing at 700 °C and that the cube texture is fully developed at temperatures higher than 800 °C, while annealing at 900 °C for 1 h produces a stable microstructure at the typical YBCO deposition conditions.

  15. Development of Solution Buffer Layers for RABiTS Based YBCO Coated Conductors

    SciTech Connect

    Paranthaman, Mariappan Parans; Qiu, Xiaofeng; List III, Frederick Alyious; Zhang, Yifei; Li, Xiaoping; Sathyamurthy, Srivatsan; Thieme, C. L. H.; Rupich, M. W.

    2011-01-01

    Abstract The main objective of this research is to find a suitable alternate solution based seed layer for the standard RABiTS three-layer architecture of physical vapor deposited CeO cap/YSZ barrier/Y O seed on Ni-5%W metal tape. In the present work, we have identified CeO buffer layer as a potential replacement for Y O seeds. Using a metal-organic deposition (MOD) process, we have grown smooth, crack-free, epitaxial thin films of CeO (pure and Zr, Cu and Gd-doped) directly on biaxially textured Ni-5W substrates in short lengths. Detailed XRD studies indicate that a single epitaxial CeO phase with slightly improved out-of-plane texture compared to the texture of the underlying Ni-W substrates can be achieved in pure, undoped CeO samples. We have also demonstrated the growth of YSZ barrier layers on pure CeO seeds using sputtering. Both sputtered CeO cap layers and MOD-YBCO films were grown epitaxially on these YSZ-buffered MOD-CeO /Ni-5W substrates. High critical currents per unit width, of 264 A/cm (critical current density, of 3.3 MA/cm ) at 77 K and 0.01 T was achieved for 0.8 m thick MOD-YBCO films grown on MOD-CeO seeds. These results indicate that CeO films can be grown directly on Ni-5W substrates and still support high performance YBCO coated conductors. This work holds promise for a route for producing low-cost buffer architecture for RABiTS based YBCO coated conductors.

  16. Practical fit functions for transport critical current versus field magnitude and angle data from (RE)BCO coated conductors at fixed low temperatures and in high magnetic fields

    NASA Astrophysics Data System (ADS)

    Hilton, D. K.; Gavrilin, A. V.; Trociewitz, U. P.

    2015-07-01

    Applications of (RE = Y, Gd)BCO coated conductors for the generation of high magnetic fields are increasing sharply, this while (RE)BCO coated conductors themselves are evolving rapidly. This article describes and demonstrates recently developed and applied mathematical models that systematically and comprehensively characterize the transport critical current angular dependence of a batch of (RE)BCO coated conductor in high magnetic fields at fixed temperatures with an uncertainty of 10% or better. The model development was based on analysis of experimental data sets from various published sources and coated conductors with different microstructures. These derivations directly are applicable to the accurate prediction of the performance in high magnetic fields of coils wound with (RE)BCO coated conductors. In particular, a nonlinear fit is discussed in this article of transport critical current at T = 4.2 K versus field and angle data. This fit was used to estimate the hysteresis losses of (RE)BCO coated conductors in high magnetic fields, and to design the inserts wound with such conductors of the all-superconducting 32 T magnet being constructed at the NHMFL. A series of such fits, recently developed at several fixed temperatures, continues to be used to simulate the quench behavior of that magnet.

  17. An equation for the quench propagation velocity valid for high field magnet use of REBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Bonura, M.; Senatore, C.

    2016-06-01

    Based on a study of the thermophysical properties, we derived a practical formula for the normal zone propagation velocity appropriate for REBa2Cu3O7-x coated conductors in high magnetic fields. An analytical expression to evaluate the current sharing temperature as a function of the operating conditions is also proposed. The presented study has allowed us to account for experimental results not fully understood in the framework of the models widely used in the literature. In particular, we provided a fundamental understanding of the experimental evidence that the normal zone propagation velocity in REBa2Cu3O7-x coated conductors can be mainly determined by the operating current, regardless of the applied field and temperature.

  18. Development of 6.6 kV/600 A superconducting fault current limiter using coated conductors

    NASA Astrophysics Data System (ADS)

    Yazawa, T.; Koyanagi, K.; Takahashi, M.; Toba, K.; Takigami, H.; Urata, M.; Iijima, Y.; Saitoh, T.; Amemiya, N.; Shiohara, Y.; Ito, T.

    2009-10-01

    As one of the programs in the Ministry of Economy, Trade and Industry (METI) project regarding R&D on superconducting coated conductor, three-phase superconducting fault current limiter (SFCL) for 6.6 kV application was developed and successfully tested. The developed SFCL was mainly comprised three-phase set of current limiting coils installed in a sub-cooled nitrogen cryostat with a GM cryocooler, circuit breakers and a sequence circuit. The whole system was installed in a cubicle. Two tapes of coated conductor were wound in parallel in each coil to obtain the rated current of 72 A rms. After developing the whole SFCL system, short circuit experiments were implemented with a short circuit generator. In a three-line ground fault test, the SFCL successfully restricted the prospected short circuit current over 1.6 kA to about 800 A by the applied voltage of 6.6 kV. The SFCL was installed in a user field and connected with a gas engine generator, followed by a consecutive operation. In this program, 600 A class FCL coil, with which four coated conductor tapes were wound, was also developed. The coil showed sufficiently low AC loss at the rated current. With these results, the program attained the planned target of the fundamentals for the 6.6 kV/600 A SFCL.

  19. Enhanced critical currents of commercial 2G superconducting coated conductors through proton irradiation

    NASA Astrophysics Data System (ADS)

    Welp, Ulrich; Leroux, M.; Kihlstrom, K. J.; Kwok, W.-K.; Koshelev, A. E.; Miller, D. J.; Rupich, M. W.; Fleshler, S.; Malozemoff, A. P.; Kayani, A.

    2015-03-01

    We report on magnetization and transport measurements of the critical current density, Jc, of commercial 2G YBCO coated conductors before and after proton irradiation. The samples were irradiated along the c-axis with 4 MeV protons. Proton irradiation produces a mixed pinning landscape composed of pre-existing rare earth particles and a uniform distribution of irradiation induced nm-sized defects. This pinning landscape strongly reduces the suppression of Jc in magnetic fields resulting in a doubling of Jc in a field of ~ 4T. The irradiation dose-dependence of Jc is characterized by a temperature and field dependent sweat spot that at 5 K and 6 T occurs around 20x1016 p/cm2. Large-scale time dependent Ginzburg-Landau simulations yield a good description of our results. This work supported by the Center for Emergent Superconductivity, an Energy Frontier Research Center funded by the U.S. D.O.E., Office of Science, Office of Basic Energy Sciences (KK, ML, AEK) and by the D.O.E, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357 (UW, WKK).

  20. Long length oxide template for YBCO coated conductor prepared by surface-oxidation epitaxy method

    NASA Astrophysics Data System (ADS)

    Watanabe, Tomonori; Matsumoto, Kaname; Maeda, Toshihiko; Tanigawa, Toru; Hirabayashi, Izumi

    2001-08-01

    A 50 m long, biaxially textured NiO buffer layer for epitaxial growth ofYBa 2Cu 3O 7- δ (YBCO) film has been fabricated on the long cube textured nickel tape using surface-oxidation epitaxy (SOE) method. The SOE-NiO layers were highly {1 0 0} <0 0 1> textured. The full width at half maximum of 10-14.5° from X-ray φ-scan ( Δφ) was in the range of 10-14.5° through the whole length. The critical current density ( Jc) values exceeding 0.3 MA/cm 2 (77 K, 0 T) have been obtained in short samples of YBCO films on NiO/Ni tapes, by using thin MgO cap layer. Thirty meters long Ni-clad Ni-20wt.%Cr (Ni/NiCr) and Ni-clad austenitic stainless steel (Ni/SS) tapes were also prepared for YBCO coated conductors with higher strength and lower magnetism than those of pure nickel tape. Highly {1 0 0} <0 0 1> textured NiO layers were formed on those textured composite tapes by SOE method as same as on cube textured pure nickel tapes. YBCO films with Jc of 0.1 MA/cm 2 (77 K, 0 T) have been obtained on MgO/SOE-NiO layer of short Ni/NiCr composite tape.

  1. Development of cube-textured Ni-W alloy substrates for YBCO-coated conductor

    NASA Astrophysics Data System (ADS)

    Kim, Kyu Tae; Lim, Jun Hyung; Kim, Jung Ho; Joo, Jinho; Nah, Wansoo; Ji, Bong Ki; Jun, Byung-Hyuk; Kim, Chan-Joong; Hong, Gye-Won

    2004-10-01

    We fabricated pure Ni and Ni-W alloy substrates for YBCO-coated conductor applications and evaluated the effect of W in Ni on texture, grain size, grain boundary and surface morphology, and hardness of the substrates. Pure Ni, Ni-2at.%W, and Ni-5at.%W alloy substrates were prepared by plasma arc melting, cold rolling, and recrystallization heat treatment at various temperatures (700-1300 °C). Substrate texture was evaluated by pole-figure and microstructure and surface morphology were investigated by optical and atomic force microscopy (AFM). We observed that the Ni-W alloy substrates had stronger cube texture that was maintained at higher annealing temperatures than seen for the pure Ni substrate: Full-width at half-maximum of in-plane texture was 13.40° for the Ni substrate and 4.42-5.57° for the Ni-W substrate annealed at 1000 °C. In addition, the Ni-W substrate had smaller grain size, less thermal grooving, and higher hardness, compared to those of the pure Ni substrate, indicating that the presence of W in Ni effectively restricts grain growth and enhances thermal stability by strengthening the grain boundary in the Ni substrate.

  2. Influence of soft ferromagnetic substrate on magneto-elastic behavior in a superconducting coated conductor strip

    NASA Astrophysics Data System (ADS)

    He, An; Xue, Cun; Yong, Huadong; Zhou, Youhe

    2013-11-01

    Ferromagnetic materials will affect not only the electromagnetic response but also the mechanical behaviors of coated conductors. The influence of soft ferromagnetic substrate on magneto-elastic behavior in a superconductor/ferromagnetic (SC/FM) bilayer exposed to a transverse magnetic field is investigated theoretically. The ferromagnetic substrate is regarded as ideal soft magnets with high permeability and small magnetic hysteresis. Due to the composite structure of SC/FM hybrids, magneto-elastic behavior will be subjected to combined effect of equivalent force and flexural moment. Analytical expressions for internal stress and strain components are derived by virtue of a two-dimensional elasticity analysis. It is worth pointing out that the y component of strain has much larger positive value during field ascent, which may result in the delamitation at the interface. Irreversible magnetostrictive behaviors are observed both along x direction and along y direction. For the thickness dependence of magnetostriction, the flexural moment dominates when the SC thickness is small while the equivalent force plays a critical role at higher SC thickness.

  3. Microstructure Characteristics of High Lift Factor MOCVD REBCO Coated Conductors With High Zr Content

    SciTech Connect

    Galstyan, E; Gharahcheshmeh, MH; Delgado, L; Xu, AX; Majkic, G; Selvamanickam, V

    2015-06-01

    We report the microstructural characteristics of high levels of Zr-added REBa2Cu3O7-x (RE = Gd, Y rare earth) coated conductors fabricated by Metal Organic Chemical Vapor Deposition (MOCVD). The enhancements of the lift factor defined as a ratio of the in-field (3 T, B parallel to c-axis) critical current density (J(c)) at 30 K and self-field J(c) at 77 K have been achieved for Zr addition levels of 20 and 25 mol% via optimization of deposition parameters. The presence of strong flux pinning is attributed to the aligned nanocolumns of BaZrO3 and nanoprecipitates embedded in REBa2Cu3O7-x matrix with good crystal quality. A high density of BZO nanorods with a typical size 6-8 nm and spacing of 20 nm has been observed. Moreover, the high Zr content was found to induce a high density of intrinsic defects, including stacking faults and dislocations. The correlation between in-field performance along the c-axis and microstructure of (Gd, Y) BCO film with a high level of Zr addition is discussed.

  4. Modeling of screening currents in coated conductor magnets containing up to 40000 turns

    NASA Astrophysics Data System (ADS)

    Pardo, E.

    2016-08-01

    Screening currents caused by varying magnetic fields degrade the homogeneity and stability of the magnetic fields created by REBCO coated conductor coils. They are responsible for the AC loss; which is also important for other power applications containing windings, such as transformers, motors and generators. Since real magnets contain coils exceeding 10000 turns, accurate modeling tools for this number of turns or above are necessary for magnet design. This article presents a fast numerical method to model coils with no loss of accuracy. We model a 10400-turn coil for its real number of turns and coils of up to 40000 turns with continuous approximation, which introduces negligible errors. The screening currents, the screening current induced field (SCIF) and the AC loss is analyzed in detail. The SCIF is at a maximum at the remnant state with a considerably large value. The instantaneous AC loss for an anisotropic magnetic-field dependent J c is qualitatively different than for a constant J c , although the loss per cycle is similar. Saturation of the magnetization currents at the end pancakes causes the maximum AC loss at the first ramp to increase with J c . The presented modeling tool can accurately calculate the SCIF and AC loss in practical computing times for coils with any number of turns used in real windings, enabling parameter optimization.

  5. Measurement of AC Losses in a Racetrack Superconducting Coil Made from YBCO Coated Conductor

    NASA Astrophysics Data System (ADS)

    Seiler, Eugen; Abrahamsen, Asger B.; Kováč, Ján; Wichmann, Mike; Træholt, Chresten

    We present the results of transport measurements of AC losses in a racetrack shaped superconducting coil made from coated conductor tape. The outer dimensions of the coil are approximately 24 cm × 12 cm and it has 57 turns. The coil is impregnated with epoxy resin and fiberglass tape is used to insulate the individual turns and to improve the mechanical properties of the epoxy when exposed to thermal cycling. The coil is manufactured as a part of the field winding of a small synchronous generator; therefore stainless steel frames are installed on the inner and outer side of the winding to reinforce it. The AC loss is measured versus the transport current Ia with the coil immersed in liquid nitrogen. Measurements at frequencies 21 Hz, 36 Hz and 72 Hz are compared. The AC losses follow Ia2 dependence at low current amplitudes and Ia3 at high amplitudes. After cutting the inner steel frame the low amplitude losses are decreased, their frequency dependence is reduced but their dependence on the current remains unchanged.

  6. Roebel assembled coated conductor cables (RACC): Ac-Losses and current carrying potential

    NASA Astrophysics Data System (ADS)

    Frank, A.; Heller, R.; Goldacker, W.; Kling, A.; Schmidt, C.

    2008-02-01

    Low ac-loss HTS cables for transport currents well above 1 kA are required for application in transformers and generators and are taken into consideration for future generations of fusion reactor coils. Coated conductors (CC) are suitable candidates for high field application at an operation temperature in the range 50-77 K. Ac-field applications require cables with low ac-losses and hence twisting of the individual strands. We solved this problem using the Roebel technique. Short lengths of Roebel bar cables were prepared from industrial DyBCO and YBCO-CC. Meander shaped tapes of 4 or 5 mm width with twist pitches of 123 or 127 mm were cut from the 10 or 12 mm wide CC tapes using a specially designed tool. Eleven or twelve of these strands were assembled to a cable. The electrical and mechanical connection of the tapes was achieved using a silver powder filled conductive epoxy resin. Ac-losses of a short sample in an external ac-field were measured as a function of frequency and field amplitude as well as the coupling current decay time constant. We discuss the results in terms of available theories and compare measured time constants in transverse field with measured coupling losses. Finally the potential of this cable type for ac-use is discussed with respect to ac-losses and current carrying capability.

  7. Voltage-ampere characteristics of YBCO coated conductor under inhomogeneous oscillating magnetic field

    NASA Astrophysics Data System (ADS)

    Geng, J.; Shen, B.; Li, C.; Zhang, H.; Matsuda, K.; Li, J.; Zhang, X.; Coombs, T. A.

    2016-06-01

    Direct current carrying type II superconductors present a dynamic resistance when subjected to an oscillating magnetic field perpendicular to the current direction. If a superconductor is under a homogeneous field with high magnitude, the dynamic resistance value is nearly independent of transport current. Hoffmann and coworkers [Hoffmann et al., IEEE Trans. Appl. Supercond. 21, 1628 (2011)] discovered, however, flux pumping effect when a superconducting tape is under an inhomogeneous field orthogonal to the tape surface generated by rotating magnets. Following their work, we report the whole Voltage-Ampere (V-I) curves of an YBCO coated conductor under permanent magnets rotating with different frequencies and directions. We discovered that the two curves under opposite rotating directions differ from each other constantly when the transport current is less than the critical current, whereas the difference gradually reduces after the transport current exceeds the critical value. We also find that for different field frequencies, the difference between the two curves decreases faster with lower field frequency. The result indicates that the transport loss is dependent on the relative direction of the transport current and field travelling, which is distinct from traditional dynamic resistance model. The work may be instructive for the design of superconducting motors.

  8. Delamination behaviour of GdBCO coated conductor tapes under transverse tension

    NASA Astrophysics Data System (ADS)

    Gorospe, A.; Nisay, A.; Dizon, J. R.; Shin, H. S.

    2013-11-01

    The electromechanical property behaviour of 2G coated conductor (CC) tapes fabricated by multi-layer deposition process both in the in-plane and transverse direction should be understood. The CC tapes are used in the fabrication of epoxy resin-impregnated coils. In such case, the Lorentz force due to the high magnetic field applied as well as the thermal stress due to the difference in coefficient of thermal expansion (CTE) among constituent layers during cooling to cryogenic temperature will induce transversely applied load to the surface of CC tapes in coils. Hence, the CC tape should have a good mechanical property in the transverse direction in order to maintain its superior performance under magnetic field. In this study, a test frame which gives precisely aligned transverse load was devised. Using the fixture, the delamination behaviours including the delamination strength of the GdBCO CC tapes under transverse tensile loading were investigated. Large variation on the delamination strength of the CC tapes was recorded and might have resulted from the slit edge effect and the inhomogeneity of the CC tapes. The Ic degradation behaviour under transverse load was related to the location where delamination occurred in the sample.

  9. Tuning Vortex Creep in Irradiated YBa2Cu3O7-δ Coated Conductors

    NASA Astrophysics Data System (ADS)

    Eley, Serena; Kihlstrom, Karen; Holleis, Sigrid; Leroux, Maxime; Rupich, Martin; Miller, Dean; Kayani, Asghar; Welp, Ulrich; Kwok, Wai-Kwong; Civale, Leonardo

    YBa2Cu3O7-δ coated conductors (CCs) show non-monotonic changes in the temperature-dependent creep rate, S (T) , due to mixed pinning landscapes comprised of twin boundaries, planar defects, point defects, and nanoparticle precipitates. Notably, in low fields, there is a conspicuous dip in S as T increases from ~20K to ~65K. The source of this dip is poorly understood. Moreover, pinning landscapes that are favorable for high critical currents, Jc, are not necessarily optimal for low S. We have found that, though oxygen irradiation introduces few-nm-sized defects that result in significant increases in Jc, it is detrimental to creep, increasing S (reducing the dip depth) for T > 20K. Understanding the source of this dip is crucial to engineering pinning landscapes that concurrently promote high Jc and low S. To this end, we study changes in S (T) as we tune the ratio of smaller (point to few-nm-sized) defects to larger nanoparticles in an oxygen-irradiated CC by annealing in O2 at 250°C to 600°C. We observe a steady decrease in S (T > 20K) with increasing annealing temperature. This suggests that pre-existing nanoparticle precipitates are likely responsible for the dip in S (T) , and underlines the fact that the effects of defects are not additive, but rather can be competitive.

  10. Fabrication of YSZ buffer layer by single source MOCVD technique for YBCO coated conductor

    NASA Astrophysics Data System (ADS)

    Jun, Byung-Hyuk; Sun, Jong-Won; Kim, Ho-Jin; Lee, Dong-Wook; Jung, Choong-Hwan; Park, Soon-Dong; Kim, Chan-Joong

    2003-10-01

    Yttria stabilized zirconia (YSZ) buffer layers were deposited by a metal organic chemical vapor deposition technique using a single liquid source for the application of YBa 2Cu 3O 7- δ (YBCO) coated conductor. Y:Zr mole ratio was 0.2:0.8, and tetrahydrofuran (THF) was used as a solvent. The (1 0 0) single crystal MgO substrate was used for searching the deposition conditions. Bi-axially oriented CeO 2 and NiO films were fabricated on {1 0 0} <0 0 1> textured Ni substrate by the same method and used as templates. At a constant working pressure of 10 Torr, the deposition temperatures (660-800 °C) and oxygen flow rates (100-500 sccm) were changed to find the optimum deposition condition. The best (1 0 0) oriented YSZ film on MgO was obtained at 740 °C and O 2 flow rate of 300 sccm. For a YSZ buffer layer with this deposition condition on a CeO 2/Ni template, full width half maximum values of the in-plane ( ϕ-scan) and out-of-plane ( ω-scan) alignments were 10.6° and 9.8°, respectively. The SEM image of YSZ film on CeO 2/Ni showed surface morphologies without microcracks. The film deposition rate was about 100 nm/min.

  11. Broad Temperature Pinning Study of 15 mol.% Zr-Added (Gd, Y)-Ba-Cu-O MOCVD Coated Conductors

    SciTech Connect

    Xu, AX; Khatri, N; Liu, YH; Majkic, G; Galstyan, E; Selvamanickam, V; Chen, YM; Lei, CH; Abraimov, D; Hu, XB; Jaroszynski, J; Larbalestier, D

    2015-06-01

    BaZrO3 (BZO) nanocolumns have long been shown to be very effective for raising the pinning force F-p of REBa2Cu3Ox (REBCO, where RE = rare earth) films at high temperatures and recently at low temperatures too. We have successfully incorporated a high density of BZO nanorods into metal organic chemical vapor deposited (MOCVD) REBCO coated conductors via Zr addition. We found that, compared to the 7.5% Zr-added coated conductor, dense BZO nanorod arrays in the 15% Zr-added conductor are effective over the whole temperature range from 77 K down to 4.2 K. We attribute the substantially enhanced J(c) at 30 K to the weak uncorrelated pinning as well as the strong correlated pinning. Meanwhile, by tripling the REBCO layer thickness to similar to 2.8 mu m, the engineering critical current density J(e) at 30 K exceeds J(e) of optimized Nb-Ti wires at 4.2 K.

  12. Degradation of the performance of a YBCO-coated conductor double pancake coil due to epoxy impregnation

    NASA Astrophysics Data System (ADS)

    Takematsu, T.; Hu, R.; Takao, T.; Yanagisawa, Y.; Nakagome, H.; Uglietti, D.; Kiyoshi, T.; Takahashi, M.; Maeda, H.

    2010-09-01

    Now that YBCO-coated conductors have been commercialized, a number of YBCO coils have been developed. However, their basic performances have not been systematically investigated so far. Here, we demonstrate that of a YBCO double pancake coil. The critical current of an epoxy impregnated YBCO double pancake coil was substantially degraded, i.e. the normal voltage appears above 8 A, only 18% of that for the dry coil. It was inferred that degradation occurs if the cumulative radial stress developed during cool down exceeds the critical transverse stress for the YBCO-coated conductor (typically 10 MPa). Under these conditions, the conductor was debonded at the interface between the buffer layer and YBCO layers, or fractured in the YBCO layer itself, causing cracks on the YBCO layer, resulting in a significant decline of the critical current. These negative effects are suppressed if the coils are dry wound or impregnated with paraffin, as the bonding strengths between turns are negligible and therefore turns are separated if the cumulative radial stress tends to be tensile. For non-circular coils in which epoxy impregnation is inevitable, degradation due to cumulative tensile transverse stress is still the major problem.

  13. Modeling AC ripple currents in HTS coated conductors by integral equations

    NASA Astrophysics Data System (ADS)

    Grilli, Francesco; Xu, Zhihan

    2016-12-01

    In several HTS applications, the superconducting tapes experience the simultaneous presence of DC and AC excitations. For example in high-current DC cables, where the transport current is not perfectly constant, but it exhibits some ripples at different frequencies introduced by the rectification process (AC-DC conversion). These ripples give rise to dissipation, whose magnitude and possible influence on the device's cooling requirements need to be evaluated. Here we report a study of the AC losses in a HTS coated conductor subjected to DC currents and AC ripples simultaneously. The modeling approach is based on an integral equation method for thin superconductors: the superconducting tape is modeled as a 1-D object with a non-linear resistivity, which includes the dependence of the critical current density Jc on the magnetic field. The model, implemented in a commercial finite-element program, runs very fast (the simulation of one AC cycle typically takes a few seconds on standard desktop workstation): this allows simulating a large number of cycles and estimating when the AC ripple losses stabilize to a constant value. The model is used to study the influence of the flux creep power index n on the stabilization speed and on the AC loss values, as well as the effect of using a field-dependent Jc instead of a constant one. The simulations confirm that the dissipation level should not be a practical concern in HTS DC cables. At the same time, however, they reveal a strong dependence of the results upon the power index n and the form of Jc , which spurs the question whether the power-law is the most suitable description of the superconductor's electrical behavior for this kind of analysis.

  14. Development of scribing process of coated conductors for reduction of AC losses

    NASA Astrophysics Data System (ADS)

    Suzuki, K.; Yoshizumi, M.; Izumi, T.; Shiohara, Y.; Iwakuma, M.; Ibi, A.; Miyata, S.; Yamada, Y.

    2008-09-01

    Coated conductors (CCs) are prospective for electric power applications intended for not only better cost performance but also high critical current density ( Jc) under magnetic fields comparing with Bi 2Sr 2Ca 2Cu 3O y (BSCCO) tapes. Furthermore, they also have a possibility to reduce AC losses by various methods of post-treatments since the CCs are of a laminated structure with the insulating buffer layers. Multifilamentation by narrowing the tape width is quite effective to reduce the AC losses and therefore this approach is valid for the standard process to fabricate practical CCs with an appropriate architecture. In this study, we developed a tape scribing technique applying a technique of YAG laser with/without chemical etching to control the filament width in YBa 2Cu 3O y (YBCO) CCs for the multifilament. The AC loss was reducible to one-twentieth by 20-multifilament structure in a short sample test, and to one-third by 3-multifilament structure in the coil using 28 m long tapes in total. The authors measured the resistance between the filaments at 60-300 K after post-treatment to investigate the effective bridged materials, which is essential for decoupling of the filaments. We improved the resistance value between the filaments at liquid nitrogen temperature up to the order of 10 Ω/cm using the YAG laser with high-temperature oxygen anneals. Furthermore, the resistance over 10 6 Ω/cm was evident by the combination of laser scribing and chemical etching, which is much higher than the requirements of all the applications.

  15. Jointing of Coated Conductors by Using Nano-particle Metal Pastes

    NASA Astrophysics Data System (ADS)

    Nakanishi, Tsuyoshi; Machi, Takato; Izumi, Teruo; Teranishi, Ryo; Kato, Tomohiro; Kato, Takeharu; Hirayama, Tsukasa

    Development of a jointing technique of coated conductors is important for all applications, such as superconducting magnets, cables, etc. Low resistance jointing techniques by means of silver diffusion [1] and for superconducting joints[2] have been reported so far. Since these processes were carried out at higher temperatures than the O2 annealing temperature for appropriate carrier doping to the REBa2Cu3O7-d (REBCO) crystals and resulted in oxygen deficiency in the REBCO crystals, long time O2 annealing was required for compensation of this oxygen deficiency. Because the long time and high temperature post annealing is an inappropriate process as on-site technology, solder jointing technology has been widely accepted, in general, for practical applications. However, the resistance of the solder joint is 50 - 100 nΩ, and then the Joule heat generation in the joint region is a serious problem and must be solved. Consequently, we have studied a new jointing technique by using the pastes containing of silver or gold nano-particles. Because the Ic value of GdBCO was deteriorated with higher temperature heat treatment, we have tried to develop a jointing technology with the low temperature (below 200°C). We used the nano-particle metal pastes (∼5 nm) which contained dispersants around the chemically active surface of nano-particles and dissociates at low temperatures and achieved the low resistance joint (∼ 3nΩ, 10 x 160 mm2, 77 K) as well as no Ic degradation without O2 post annealing.

  16. Note: Effective anvil size for transverse delamination test of rare-earth-Ba₂Cu₃Oy coated conductor tapes.

    PubMed

    Shin, Hyung-Seop; Gorospe, Alking B; Dedicatoria, Marlon J

    2015-10-01

    In coated conductor (CC) tapes used in magnet and coil applications, delamination due to excessive transverse tensile stresses is still one of the major issues that need considerations. Recently, several methods in evaluating the delamination strength of CC tapes are being used. In the case of anvil test, size of the anvils will be an important factor considering its applications (i.e., superconducting coil impregnation). In this study, delamination strength of CC tape was examined using different upper anvil sizes and their effects were discussed. Finally, reasonable sizes of upper anvil to be used were proposed considering the application conditions.

  17. Note: Effective anvil size for transverse delamination test of rare-earth-Ba2Cu3Oy coated conductor tapes

    NASA Astrophysics Data System (ADS)

    Shin, Hyung-Seop; Gorospe, Alking B.; Dedicatoria, Marlon J.

    2015-10-01

    In coated conductor (CC) tapes used in magnet and coil applications, delamination due to excessive transverse tensile stresses is still one of the major issues that need considerations. Recently, several methods in evaluating the delamination strength of CC tapes are being used. In the case of anvil test, size of the anvils will be an important factor considering its applications (i.e., superconducting coil impregnation). In this study, delamination strength of CC tape was examined using different upper anvil sizes and their effects were discussed. Finally, reasonable sizes of upper anvil to be used were proposed considering the application conditions.

  18. The Effect of Strain on Grains and Grain Boundaries in YBa2Cu3O7-Delta Coated Conductors (Postprint)

    DTIC Science & Technology

    2009-12-09

    sample had a 2.5◦ GB isolated with the FIB and one had a 4◦ GB. The 200 nm thick YBCO thin films were deposited by pulsed-laser deposition on 4 mm × 12...transport current critical current density (Jc) of YBa2Cu3O7−δ ( YBCO ) coated conductors that are produced with metal–organic deposition (MOD) was...boundaries from the two kinds of YBCO samples can be expressed by the same function, however with a greater effective tensile strain at the grain

  19. Co-evaporated YBCO/doped-CeO 2/Ni-W coated conductors oxygen improved using a supersonic nozzle

    NASA Astrophysics Data System (ADS)

    Gilioli, E.; Baldini, M.; Bindi, M.; Bissoli, F.; Pattini, F.; Rampino, S.; Ginocchio, S.; Gauzzi, A.; Rocca, M.; Zannella, S.

    2007-10-01

    A novel process for the coated conductors (CC) deposition, characterized by a single CeO2 buffer layer architecture, and a new oxygenation device for the YBCO layer has been developed. In CC technology, usually the ceria layer thickness must be less than 100 nm to avoid the formation of cracks; in order to ensure an efficient barrier effect, complex and costly multi-buffer layers architectures must be grown. In this work, we describe the way to increase the thickness of crack-free single buffer layer.

  20. Design and test of current limiting modules using YBCO-coated conductors

    NASA Astrophysics Data System (ADS)

    Schmidt, W.; Gamble, B.; Kraemer, H.-P.; Madura, D.; Otto, A.; Romanosky, W.

    2010-01-01

    Within the cooperation between American Superconductor Corporation (AMSC) and Siemens Corporate Technology we have investigated the fault current limiting performance of YBCO-coated conductors (also called second-generation or 2G HTS wires) stabilized with stainless steel laminates. Design rules for the length and width of the wire depending on utility grid requirements have been established. Bifilar coils have been manufactured and tested with a typical limitation period of 50 ms under stepwise increasing voltage loads to determine the maximum temperature the wires can withstand without degradation. Coils have been assembled into limiter modules demonstrating uniform tripping of the individual coils and recovery within seconds. At present this cooperation is proceeding within a joint project funded by the US Department of Energy (DOE) that encompasses the design, construction and testing of a 115 kV FCL for power transmission within a time frame of 4-5 years, and additional partners. Besides AMSC and Siemens, Nexans contributes the high voltage terminations and Los Alamos National Lab investigates the ac losses. Installation and testing are planned for a Southern California Edison substation. The module planned for the transmission voltage application consists of 63 horizontally arranged coils connected in parallel and series to account for a rated current of 1.2 kArms and voltage of 31 kVrms plus margins. The rated voltage of the module is considerably lower than the line to ground voltage in the 115 kV grid owing to our shunted limiter concept. The shunt reactor connected in parallel to the module outside the cryostat allows for adjustment of the limited current and reduces voltage drop across the module in case of a fault. The fault current reduction ratio is 42% for our present design. A subscale module comprising six full-size coils has been assembled and tested recently to validate the coil performance and coil winding technique. The module had a critical

  1. High current superconductivity in FeSe0.5Te0.5-coated conductors at 30 tesla.

    PubMed

    Si, Weidong; Han, Su Jung; Shi, Xiaoya; Ehrlich, Steven N; Jaroszynski, J; Goyal, Amit; Li, Qiang

    2013-01-01

    Although high-temperature superconductor cuprates have been discovered for more than 25 years, superconductors for high-field application are still based on low-temperature superconductors, such as Nb(3)Sn. The high anisotropies, brittle textures and high manufacturing costs limit the applicability of the cuprates. Here we demonstrate that the iron superconductors, without most of the drawbacks of the cuprates, have a superior high-field performance over low-temperature superconductors at 4.2 K. With a CeO(2) buffer, critical current densities >10(6)  A cm(-2) were observed in iron-chalcogenide FeSe(0.5)Te(0.5) films grown on single-crystalline and coated conductor substrates. These films are capable of carrying critical current densities exceeding 10(5) A cm(-2) under 30 tesla magnetic fields, which are much higher than those of low-temperature superconductors. High critical current densities, low magnetic field anisotropies and relatively strong grain coupling make iron-chalcogenide-coated conductors particularly attractive for high-field applications at liquid helium temperatures.

  2. Development of a superconducting joint between a GdBa2Cu3O7-δ-coated conductor and YBa2Cu3O7-δ bulk: towards a superconducting joint between RE (Rare Earth) Ba2Cu3O7-δ-coated conductors

    NASA Astrophysics Data System (ADS)

    Jin, Xinzhe; Yanagisawa, Yoshinori; Maeda, Hideaki; Takano, Yoshiki

    2015-07-01

    We have started to develop a superconducting bridge joint between two GdBa2Cu3O7-δ (Gd123)-coated conductors, where both conductors are placed in an end-to-end arrangement on the surface of a melt-textured YBCO (including Y2BaCuO5 and YBa2Cu3O7-δ) bulk, which acts as a superconducting medium between the coated conductors. As a first step in the development, one half of the bridge joint assembly was modeled and investigated. Experimental results achieved are as follows: (a) the higher-melting-temperature textured Gd123-coated conductor acts as a seed for the melt texture of the YBa2Cu3O7-δ (Y123) bulk, and (b) the superconducting phase continues across the Y123/Gd123 boundary. The critical current of the joint model is 10 A, which is about 10% of the original Gd123-coated conductor, at 77 K in a self-magnetic field. These results are considered to be extensible to the superconducting bridge joint between the Gd123-coated conductors.

  3. New chemical approach to obtain dense layer phosphate-based ionic conductor coating on negative electrode material surface: Synthesis way, outgassing and improvement of C-rate capability

    NASA Astrophysics Data System (ADS)

    Fleutot, Benoit; Davoisne, Carine; Gachot, Grégory; Cavalaglio, Sébastien; Grugeon, Sylvie; Viallet, Virginie

    2017-04-01

    Li4Ti5O12 (LTO) based batteries have severe gassing behavior during charge/discharge and storage process, due to interfacial reactions between active material and electrolyte solution. In the same time, the electronic and ionic conductivity of pristine LTO is very poor and induces the use of nanoparticles which increase the outgassing phenomena. The coating of LTO particles could be a solution. For this the LTO spinel particles are modified with ionic conductor Li3PO4 coating using a spray-drying method. For the first time a homogeneous thin dense layer phosphate based conductor is obtained without nanoparticles, as a thin film material. It is so possible to study the influence of ionic conductor deposited on the negative electrode material on performances by the controlled layer thickness. This coating was characterized by XRD, SEM, XPS and TEM. The electrochemical performance of Li3PO4 coated Li4Ti5O12 is improved at high C-rate by the surface modification (improvement of 30 mAh g-1 at 5 C-rate compared to pristine LTO for 5 nm of coating), inducing by a modification of surface energy. An optimum coating thickness was studied. This type of coating allows a significant decrease of outgassing phenomena due the conformal coating and opens the way to a great number of studies and new technologies.

  4. Three-Dimensional Highly Stretchable Conductors from Elastic Fiber Mat with Conductive Polymer Coating.

    PubMed

    Duan, Shasha; Wang, Zhihui; Zhang, Ling; Liu, Jin; Li, Chunzhong

    2017-09-13

    The manufacture of stretchable conductors with well-reserved electrical performance under large-degree deformations via scalable processes remains of great importance. In this work, a highly stretchable 3D conductive framework consisting of a polyurethane fiber mat (PUF) and poly(3,4-ethylenedioxythiophene) (PEDOT) is reported through facile approaches, electrospinning, and in situ interfacial polymerization, which was then backfilled with poly(dimethylsiloxane) to obtain 3D conductors. The excellent stretchability of the 3D conductive network imparted the as-prepared electrode a superior mechanical durability. Moreover, the applied strains can be effectively accommodated by the arrangement and orientation of the fibers resulting in a relatively stable electrical performance with only a 20% increased resistance at 100% stretching. Meanwhile, the resistance of the conductor could remain constant during 2000 bending cycles and showed a slight increase during 100 cycles of 50% stretching. The potential in the applications of large-area stretchable electrodes was demonstrated by the construction of LED arrays with the PUF-based conductors as electrical connections.

  5. Barrier efficiency of sponge-like La2Zr2O7 buffer layers for YBCO-coated conductors

    NASA Astrophysics Data System (ADS)

    Molina, Leopoldo; Tan, Haiyan; Biermans, Ellen; Batenburg, Kees J.; Verbeeck, Jo; Bals, Sara; Van Tendeloo, Gustaaf

    2011-06-01

    Solution derived La2Zr2O7 films have drawn much attention for potential applications as thermal barriers or low-cost buffer layers for coated conductor technology. Annealing and coating parameters strongly affect the microstructure of La2Zr2O7, but different film processing methods can yield similar microstructural features such as nanovoids and nanometer-sized La2Zr2O7 grains. Nanoporosity is a typical feature found in such films and the implications for the functionality of the films are investigated by a combination of scanning transmission electron microscopy (STEM), electron energy-loss spectroscopy (EELS) and quantitative electron tomography. Chemical solution based La2Zr2O7 films deposited on flexible Ni-5 at.%W substrates with a {100}lang001rang biaxial texture were prepared for an in-depth characterization. A sponge-like structure composed of nanometer-sized voids is revealed by high-angle annular dark-field scanning transmission electron microscopy in combination with electron tomography. A three-dimensional quantification of nanovoids in the La2Zr2O7 film is obtained on a local scale. Mostly non-interconnected highly faceted nanovoids compromise more than one-fifth of the investigated sample volume. The diffusion barrier efficiency of a 170 nm thick La2Zr2O7 film is investigated by STEM-EELS, yielding a 1.8 ± 0.2 nm oxide layer beyond which no significant nickel diffusion can be detected and intermixing is observed. This is of particular significance for the functionality of YBa2Cu3O7 - δ coated conductor architectures based on solution derived La2Zr2O7 films as diffusion barriers.

  6. Low AC Loss YBCO Coated Conductor Geometry by Direct Inkjet Printing

    SciTech Connect

    Rupich, Martin, Dr.; Duckworth, Robert, Dr.

    2009-10-01

    The second generation (2G) high temperature superconductors (HTS) wire offers potential benefits for many electric power applications, including ones requiring filamentized conductors with low ac loss, such as transformers and fault current limiters. However, the use of 2G wire in these applications requires the development of both novel multi-filamentary conductor designs with lower ac losses and the development of advanced manufacturing technologies that enable the low-cost manufacturing of these filamentized architectures. This Phase I SBIR project focused on testing inkjet printing as a potential low-cost, roll-to-roll manufacturing technique to fabricate potential low ac loss filamentized architectures directly on the 2G template strips.

  7. Roebel cables from REBCO coated conductors: a one-century-old concept for the superconductivity of the future

    NASA Astrophysics Data System (ADS)

    Goldacker, Wilfried; Grilli, Francesco; Pardo, Enric; Kario, Anna; Schlachter, Sonja I.; Vojenčiak, Michal

    2014-09-01

    Energy applications employing high-temperature superconductors (HTS), such as motors/generators, transformers, transmission lines and fault current limiters, are usually operated in the alternate current (ac) regime. In order to be efficient, the HTS devices need to have a sufficiently low value of ac loss, in addition to the necessary current-carrying capacity. Most applications are operated with currents beyond the current capacity of single conductors and consequently require cabled conductor solutions with much higher current carrying capacity, from a few kA up to 20-30 kA for large hydro-generators. A century ago, in 1914, Ludwig Roebel invented a low-loss cable design for copper cables, which was successively named after him. The main idea behind Roebel cables is to separate the current in different strands and to provide a full transposition of the strands along the cable direction. Nowadays, these cables are commonly used in the stator of large generators. Based on the same design concept of their conventional material counterparts, HTS Roebel cables from REBCO coated conductors were first manufactured at the Karlsruhe Institute of Technology and have been successively developed in a number of varieties that provide all the required technical features such as fully transposed strands, high transport currents and low ac losses, yet retaining enough flexibility for a specific cable design. In the past few years a large number of scientific papers have been published on the concept, manufacturing and characterization of such cables. Therefore it is timely for a review of those results. The goal is to provide an overview and a succinct and easy-to-consult guide for users, developers, and manufacturers of this kind of HTS cable.

  8. High-performance FeSe0.5Te0.5 thin films fabricated on less-well-textured flexible coated conductor templates

    NASA Astrophysics Data System (ADS)

    Xu, Zhongtang; Yuan, Pusheng; Ma, Yanwei; Cai, Chuanbing

    2017-03-01

    We report on the transport properties of FeSe0.5Te0.5 (FST) thin films fabricated on less-well-textured flexible coated conductor templates with LaMnO3 (LMO) as buffer layers using pulsed laser deposition. The LMO buffer layers exhibit large in-plane misalignment of ˜7.72°, which is unfavorable for cuprate-coated conductors due to the high grain boundaries. The FST thin films show a superconducting transition temperature of 16.8 K, higher than that of bulk materials due to the compressive strain between LMO and FST. Atomic force microscopy observations reveal that island-like features appear at the surfaces of both LMO and FST, confirming the island growth mode. A self-field transport critical-current density of up to 0.43 MA cm-2 at 4.2 K has been observed in FST thin films, which is much higher than that in powder-in-tube processed FST tapes. The films are capable of carrying current densities of over 105 A cm-2 in the whole applied magnetic field up to 9 T, showing great potential for high-field applications. The results indicate that, for FST, highly textured metal tapes are not needed to produce coated conductors with high performance, which is of great advantage over cuprate-coated conductors.

  9. Approaches in controllable generation of artificial pinning center in REBa2Cu3O y -coated conductor for high-flux pinning

    NASA Astrophysics Data System (ADS)

    Yoshida, Y.; Miura, S.; Tsuchiya, Y.; Ichino, Y.; Awaji, S.; Matsumoto, K.; Ichinose, A.

    2017-10-01

    This paper reviews the progress of studies to determine optimum shapes of the artificial pinning center (APC) of REBa2Cu3O y thin films and coated conductors towards superconducting magnets operating at temperatures of 77 K or less. Superconducting properties vary depending on the kind and quantity of BaMO3 materials. Therefore, we study changes in the shapes of nanorods that are due to the difference in the quality of additives and growth temperature. In addition, we aim to control the APC using an optimum shape that matches the operating temperature. In particular, we describe the shape control of nanorods in SmBCO thin films and coated conductors by employing lower temperature growth (LTG) technology using seed layers. From the cross-sectional transmission electron microscopy observations, we confirmed that using the LTG method, the BaHfO3 (BHO) nanorods, which were comparatively thin and short in length, formed a firework structure in the case of SmBCO films with coated conductors. The superconducting properties in the magnetic field of the SmBCO-coated conductor with the optimum amount of BHO showed that {F}{{p}}\\max = 1.6 TN m-3 on a single crystalline substrate and 1.5 TN m-3 on metallic substrate with a biaxially textured MgO layer fabricated by ion-beam assisted deposition method tape 4.2 K.

  10. TOPICAL REVIEW: Importance of low-angle grain boundaries in YBa2Cu3O7-δ coated conductors

    NASA Astrophysics Data System (ADS)

    Durrell, J. H.; Rutter, N. A.

    2009-01-01

    Over the past ten years the perception of grain boundaries in YBa2Cu3O7-δ conductors has changed greatly. They are now not a problem to be eliminated, but an inevitable and potentially favourable part of the material. This change has arisen as a consequence of new manufacturing techniques which result in excellent grain alignment, reducing the spread of grain boundary misorientation angles. At the same time there is considerable recent evidence which indicates that the variation of properties of grain boundaries with mismatch angle is more complex than a simple exponential decrease in critical current. This is due to the fact that low-angle grain boundaries represent a qualitatively different system to high-angle boundaries. The time is therefore right for a targeted review of research into low-angle YBa2Cu3O7-δ grain boundaries. This article does not purport to be a comprehensive review of the physics of grain boundaries as found in YBa2Cu3O7-δ in general; for a broader overview we would recommend that the reader consult the comprehensive review of Hilgenkamp and Mannhart (2002 Rev. Mod. Phys. 74 485). The purpose of this article is to review the origin and properties of the low-angle grain boundaries found in YBa2Cu3O7-δ coated conductors both individually and as a collective system.

  11. Microstructure and Thermal Oxidation of Cube Textured NiCrW Metallic Substrate for HTS Coated Conductors

    NASA Astrophysics Data System (ADS)

    Tuissi, A.; Villa, E.; Zamboni, M.

    The non-magnetic highly resistant to oxygenation Ni88Cr8W4 tape demonstrated to be a good metallic substrate for the production high Tc coated conductors. In this work rhe rolling assisted biaxially textured substrates (RABiTS) method has been used to promote a sharp (100)[001] texture on NiCrW metallic tape. The influence of the critical processing parameters on the cube texture development of the tape is investigated Moreover thermal oxidation of the textured NiCrW substrate has been performed at several conditions to study the oxide growth on the surface. Electron BackScatter Diffraction (EBSD) analysis was used for high resolution crystal orientation mapping of the surfaces. The microstructure of the substrates has also been investigated by X-ray and SEM. Differential thermal analysis (TG/DTA) was used to study the oxidation behavior of the NiCrW tapes.

  12. Intrinsic strain effect on critical current in Cu-stabilized GdBCO coated conductor tapes with different substrates

    NASA Astrophysics Data System (ADS)

    Shin, Hyung-Seop; Dedicatoria, Marlon J.

    2013-05-01

    The intrinsic strain effect on critical current, Ic in Cu-stabilized GdBCO coated conductor (CC) tapes under bending and uniaxial tension has been investigated. The bending deformation tolerance of Ic in GdBCO CC tapes, fabricated by reactive co-evaporation by deposition and reaction (RCE-DR) with substrate materials of Hastelloy and stainless steel and fabricated by the metal organic chemical vapour deposition (MOCVD) process was evaluated. The intrinsic strain response of Ic under bending was found to be independent of the fabrication process, the substrate material and the geometry of the sample. For samples with a Hastelloy substrate, the intrinsic strain response of Ic/Icmax under bending was well correlated with those under uniaxial tension. However, for samples with a stainless steel substrate, these had a large strain sensitivity for Ic under uniaxial tension even though this showed a much higher irreversible strain limit up to 1.05%.

  13. Trapping a magnetic field of 7.9 T using a bulk magnet fabricated from stack of coated conductors

    NASA Astrophysics Data System (ADS)

    Tamegai, T.; Hirai, T.; Sun, Y.; Pyon, S.

    2016-11-01

    We have fabricated a bulk magnet using double stack, each 130 layers, of short segments of coated conductors (CCs). The bulk magnet is magnetized by field-cooling in a magnetic field of 9 T down to 4.2 K. After reducing the magnetic field down to zero, we have successfully trapped a magnetic field of 7.9 T at the centre of the double stack. The magnetic field profile of the bulk magnet is calculated by fully considering the Jc(B) characteristics of the short segment of the CC. The trapped magnetic field values measured by Hall probes at three locations near the centre of the double stacks agree reasonably well with the calculated magnetic induction.

  14. Pulsed laser deposition of epitaxial YBCO/oxide multilayers onto textured metallic substrates for coated conductor applications

    NASA Astrophysics Data System (ADS)

    Tomov, R. I.; Kursumovic, A.; Kang, D. J.; Glowacki, B. A.; Majoros, M.; Evetts, J. E.; Tuissi, A.; Villa, E.

    2002-08-01

    Pulsed laser deposition of different CeO 2 based buffer architectures have been performed onto biaxially textured Ni-based substrates. The potential of both industrially available low-oxygen resistant magnetic. NiFe and NiCrW substrates have been explored. An attempt to reveal the influence CeO 2 target doping and processing environment (vacuum or forming gas) on the formation of NiO as well as in-plane and out-of-plane orientation of the first buffer has been made. XRD has been used for layer texture characterisation. As-deposited YBCO layers were highly aligned on both types of substrate with out-of-plane and in-plane ω and ϕ scans having best FWHM values of 4° and 10° respectively. The quality of YBCO tapes as full-coated conductors or seeds for high-rate epitaxial growth by LPE is evaluated.

  15. Pulsed laser deposition of epitaxial YBCO/oxide multilayers onto textured metallic substrates for coated conductor applications

    NASA Astrophysics Data System (ADS)

    Tomov, R. I.; Bramley, A. P.; Kursumovic, A.; Evetts, J. E.; Glowacki, B. A.; Tuissi, A.; Villa, E.

    2001-04-01

    The development of a viable HTS coated conductor technology requires the deposition of biaxially aligned Y1Ba2Cu3CuO7-y (YBCO) layers onto flexible metallic substrates. Using pulsed laser deposition (PLD) YBCO/CeO2/YSZ heterostructures have been deposited onto biaxially textured Ni and Ni-alloy substrates. The influence of the critical processing parameters on the texture is investigated and some of the issues involved in the deposition of heterostructures are discussed. The texture in the layers has been characterized using X-ray Diffraction (XRD). The as deposited architecture shows YBCO layers with biaxial alignment with XRD (omega) and (phi) scans having best FWHM values of 3.5 degrees and 11 degrees respectively. The growth of the layers has also been studied using Atomic Force Microscopy. Tc at 90 K with sharp transition ((Delta) equals 2K) have been measured.

  16. Another approach for controlling size and distribution of nanoparticles in coated conductors fabricated by the TFA-MOD method

    NASA Astrophysics Data System (ADS)

    Nakaoka, K.; Yoshida, R.; Kimura, K.; Kato, T.; Usui, Y.; Izumi, T.; Shiohara, Y.

    2017-05-01

    A new process, which is conceptually different from that reported so far, was developed for positive and direct control of the size and distribution of BaZrO3 (BZO) nanoparticles acting as the effective magnetic flux pinning centers for coated conductors (CCs) fabricated on buffered metal substrates by the trifluoroacetate-based metal-organic decomposition method. The (Y,Gd)Ba2Cu3O6+δ (YGdBCO) phase crystallization heat-treatment process was applied one time to a multi-layered precursor prepared by repeating the coating/calcination process of the extremely thin layer of a few tens of nanometers. The size of BZO nanoparticles refined with thinning the once coated film thickness (d once) even in the same total film thickness of 0.6-0.7 μm, consequently the critical current density in magnetic-field (J c(B)) was increased. A YGdBCO CC fabricated with d once of 30 nm revealed very high J c(B∣∣c) characteristics of 0.26 and 1.60 MA cm-2 at 77 and 65 K, respectively, for 3.0 T.

  17. A single oxide buffer layer on a cube-textured Ni substrate for the development of YBCO coated conductors by photo-assisted MOCVD

    NASA Astrophysics Data System (ADS)

    Zeng, Jianming; Ignatiev, Alex; Zhou, Yuxiang; Salama, Kamel

    2006-08-01

    Large-scale commercial applications of high-temperature superconducting (HTS) YBa2Cu3O7-x (YBCO)-based second generation coated conductors require simple and cost-effective process technologies to fabricate the buffer layer(s) and YBCO superconducting layer. Sm0.2Ce0.8O2+x (SCO) thick films have been epitaxially deposited on roll-textured Ni substrates as the single buffer layer for HTS coated conductors by using high-rate photo-assisted metal-organic chemical vapour deposition (PhAMOCVD) at a relatively low deposition temperature of 600 °C. YBCO superconducting films were then successfully deposited on these thick SCO single buffer layers by the same high-rate PhAMOCVD process, and yielded critical current densities (Jc) of ~0.52 MA cm-2 at 77 K and zero applied field. X-ray diffraction and scanning electron microscope analyses of SCO/Ni samples revealed very good crystalline structure and surface morphology for the SCO single buffer layers. These results suggest that SCO single buffer layer, as well as the YBCO conductors, fabricated by the high-rate PhAMOCVD technique may offer great potential for manufacturing YBCO coated conductors.

  18. Electro-mechanical properties of REBCO coated conductors from various industrial manufacturers at 77 K, self-field and 4.2 K, 19 T

    NASA Astrophysics Data System (ADS)

    Barth, C.; Mondonico, G.; Senatore, C.

    2015-04-01

    Rare-Earth-barium-copper-oxide tapes are now available from several industrial manufacturers and are very promising conductors in high field applications. Due to diverging materials and deposition processes, these manufacturers’ tapes can be expected to differ in their electro-mechanical and mechanical properties. For magnets designers, these are together with the conductors’ in-field critical current performance of the highest importance in choosing a suitable conductor. In this work, the strain and stress dependence of the current carrying capabilities as well as the stress and strain correlation are investigated for commercial coated conductors from Bruker HTS, Fujikura, SuNAM, SuperOx and SuperPower at 77 K, self-field and 4.2 K, 19 T.

  19. Dynamic resistance of a high-T c coated conductor wire in a perpendicular magnetic field at 77 K

    NASA Astrophysics Data System (ADS)

    Jiang, Zhenan; Toyomoto, Ryuki; Amemiya, Naoyuki; Zhang, Xingyou; Bumby, Chris W.

    2017-03-01

    Superconducting high-T c coated conductor (CC) wires comprise a ceramic thin film with a large aspect ratio. This geometry can lead to significant dissipative losses when exposed to an alternating magnetic field. Here we report experimental measurements of the ‘dynamic resistance’ of commercially available SuperPower and Fujikura CC wires in an AC perpendicular field. The onset of dynamic resistance occurs at a threshold field amplitude, which is determined by the total DC transport current and the penetration field of the conductor. We show that the field-dependence of the normalised magnetisation loss provides an unambiguous value for this threshold field at zero transport current. From this insight we then obtain an expression for the dynamic resistance in perpendicular field. This approach implies a linear relationship between dynamic resistance and applied field amplitude, and also between threshold field and transport current and this is consistent with our experimental data. The analytical expression obtained yields values that closely agree with measurements obtained across a wide range of frequencies and transport currents, and for multiple CC wires produced by different wire manufacturers and with significantly differing dimensions and critical currents. We further show that at high transport currents, the measured DC resistance includes an additional nonlinear term which is due to flux-flow resistance incurred by the DC transport current. This occurs once the field-dependent critical current of the wire falls below the DC transport current for part of each field cycle. Our results provide an effective and simple approach to calculating the dynamic resistance of a CC wire, at current and field magnitudes consistent with those expected in superconducting machines.

  20. Effects of room-temperature tensile fatigue on critical current and n-value of IBAD-MOCVD YBa2Cu3O7-x /Hastelloy coated conductor

    NASA Astrophysics Data System (ADS)

    Rogers, Samuel; Kan Chan, Wan; Schwartz, Justin

    2016-08-01

    REBa2Cu3O7-x (REBCO) coated conductors potentially enable a multitude of superconducting applications, over a wide range of operating temperatures and magnetic fields, including high-field magnets, energy storage devices, motors, generators, and power transmission systems (Zhang et al 2013 IEEE Trans. Appl. Supercond. 23 5700704). Many of these are AC applications and thus the fatigue properties may be limiting (Vincent et al 2013 IEEE Trans. Appl. Supercond. 23 5700805). Previous electromechanical studies have determined the performance of REBCO conductors under single cycle loads (Barth et al 2015 Supercond. Sci. Technol. 28 045011), but an understanding of the fatigue properties is lacking. Here the fatigue behavior of commercial ion beam assisted deposition-metal organic chemical vapor deposition REBCO conductors on Hastelloy substrates is reported for axial tensile strains up to 0.5% and up to 100 000 cycles. Failure mechanisms are investigated via microstructural studies. Results show that REBCO conductors retained I c(ɛ)/I c0 = 0.9 for 10 000 cycles at ɛ = 0.35% and ɛ = 0.45% strain, and ɛ = 0.5% for 100 cycles. The main cause of fatigue degradation in REBCO conductors is crack propagation that initiates at the slitting defects that result from the manufacturing process.

  1. Chemically deposited La2Zr2O7 buffer layers for YBCO-coated conductors: film growth and microstructure

    NASA Astrophysics Data System (ADS)

    Molina, L.; Knoth, K.; Engel, S.; Holzapfel, B.; Eibl, O.

    2006-11-01

    An adequate buffer layer architecture is of great importance for YBa2Cu3O7-δ (YBCO)-coated conductor fabrication. We present a transmission electron microscopy (TEM) analysis of La2Zr2O7 (LZO) buffer layers on biaxially textured Ni-5 at.%W substrates for YBCO-coated conductors prepared by chemical solution deposition (CSD). The LZO thin films were heat-treated at 900 and 1050 °C respectively. Electron diffraction patterns, and bright and dark-field images were used to determine the microstructure, texture and the nanoporosity of the films. By x-ray diffraction the films were found to be [100] oriented and strongly biaxially textured. Although x-ray diffraction suggests an epitaxial growth of LZO on Ni it was shown by TEM that this was not the case. The grain size of the films is between 100 and 300 nm and therefore much smaller than the Ni grain size of 40 µm. Appropriate acquisition conditions for scanning electron microscopy (SEM) and TEM imaging are given to identify the nanogranularity of the films. For the film annealed at 1050 °C high-resolution SEM images clearly show a polycrystalline LZO microstructure and the grain size can readily be determined. Electron diffraction rings are more pronounced than for the film annealed at 900 °C, indicating a higher level of polycrystallinity in the film. SEM images of the film annealed at 900 °C yield no evidence of a polycrystalline microstructure; only single misoriented LZO grains separated by 500 nm are observed. Nanovoids 10-40 nm in size were found in the LZO buffer layers with a high density. The voids had approximately cuboid shape, indicating an anisotropy of the surface energy in LZO. The surface planes of the voids were identified as {111} lattice planes. Despite the nanoporosity, which is a typical feature of CSD-grown buffer layers, the LZO buffer layers act as efficient Ni diffusion barriers. Energy dispersive x-ray microanalysis (EDX) in the transmission electron microscope yielded the composition of

  2. New Approach to Depositing Yttria-Stabilized Zirconia Buffer Layers for Coated Conductors (Postprint)

    DTIC Science & Technology

    2012-02-01

    oxides, making the approach industrially scalable and economical. 15. SUBJECT TERMS high-temperature superconductors , critical current density...industrially scalable and economical. I. INTRODUCTION High-temperature superconductor (HTS)-coated con- ductors represent the next generation of HTS wire...tech- nology, with primary application in power generation, power transmission, and compact motors for both com- mercial and military use. HTS tapes

  3. Study on the interactions between the coatings of electric conductor or dielectric media and piezoelectric substrate in the piezoelectric functional devices

    NASA Astrophysics Data System (ADS)

    Hou, Peng-Fei; Zhang, Yang; Chen, Bing-Jie

    2017-09-01

    Because that most of piezoelectric functional devices are combined with the coatings of electric conductor or dielectric media and the piezoelectric substrate, the study on the interactions between them is valuable for their advanced design. In this paper, a method for the electro-mechanical coupling fields in these piezoelectric functional devices is presented. Firstly, the two-dimensional Green's function for a normal line force or line charge is derived. Then, based on the obtained Green's function, the interaction mechanism between the coatings of electric conductor or dielectric media and the piezoelectric substrate is studied. Finally, the electro-mechanical coupling fields under arbitrary loads are obtained by superposition principle and Gauss integration. Numerical results show that this method has high computational precision, efficiency and stability. And it can be used to improve the reliability and working performance of the piezoelectric functional device effectively.

  4. Nanostructural Characterization of Low Resistance Joints Using Ag Pastes for GdBa2Cu3O7-x Coated Conductors

    NASA Astrophysics Data System (ADS)

    Kato, Tomohiro; Machi, Takato; Yokoe, Daisaku; Yoshida, Ryuji; Kato, Takeharu; Izumi, Teruo; Hirayama, Tsukasa; Shiohara, Yuh

    2017-07-01

    GdBa2Cu3O7-x coated conductors were splice jointed by a face-to-face manner using a paste containing nano-sized Ag particles under a pressure of about 50 MPa at 150 °C for 1 hr. The low electrical resistance of 6 nΩ at the joint was attained. Nanostructural characterizations of the starting Ag paste and the jointed region of the coated conductors were carried out using scanning electron microscopy and transmission electron microscopy. The size of the Ag particles in the starting pastes were confirmed to be a few tens of nanometers in diameter. The size of Ag particles became larger during the jointing process. Both the surfaces of the stabilizing Ag layers were partially bonded by the Ag particles. No oxides or other elements were detected in the region of the bonding parts.

  5. buffer Layer Growth, the Thickness Dependence of Jc in Coated Conductors, Local Identification of Current Limiting Mechanisms and Participation in the Wire Development Group

    SciTech Connect

    Larbalestier, David; Hellstron, Eric; Abraimov, Dmytro

    2011-12-17

    The primary thrusts of our work were to provide critical understanding of how best to enhance the current-carrying capacity of coated conductors. These include the deconstruction of Jc as a function of fim thickness, the growth of in situ films incorporating strong pinning centers and the use of a suite of position-sensitive tools that enable location and analysis of key areas where current-limiting occurs.

  6. Pre-oxidized cube textured nickel tapes for YBa 2Cu 3O x coated conductors

    NASA Astrophysics Data System (ADS)

    Eickemeyer, J.; Selbmann, D.; Wendrock, H.; Hühne, R.; Hänisch, J.; Holzapfel, B.

    2007-09-01

    A homogeneous nickel oxide film epitaxially grown on cube textured nickel tapes was prepared as a first buffer layer for subsequent buffer and YBa 2Cu 3O x (YBCO) layer depositions. The nickel oxide film was produced under growth conditions of surface oxidation epitaxy (SOE). The preparation of homogeneous oxide films by SOE with a high texture quality and without disturbing columnar oxide growth succeeded on micro-alloyed nickel tapes. Cerium, yttrium and silver are proven beneficial elements for micro-alloying in this respect. In silver doped metallic substrates, the cube oriented grains were produced with an increased grain aspect ratio, which was transferred to the SOE nickel oxide. Increased transport currents in the YBCO coatings were measured in the longitudinal direction of the tapes, which were coated with an additional system of buffer layers. The critical current density reached up to Jc = 2.35 MA/cm 2 at 77 K in self field.

  7. Reliable fabrication process for long-length multi-filamentary coated conductors by a laser scribing method for reduction of AC loss

    NASA Astrophysics Data System (ADS)

    Machi, T.; Nakao, K.; Kato, T.; Hirayama, T.; Tanabe, K.

    2013-10-01

    We have developed a reliable fabrication process based on a laser scribing method for multi-filamentary coated conductors with a low alternating current loss. This process consists of shallow laser irradiation and two-step chemical etching. The shallow laser irradiation, which penetrates into only a masking polymer tape and a silver stabilizing layer, suppresses generation of dross that is formed due to melting and hardening of a metal substrate. The two-step chemical etching individually for the stabilizing and the superconducting layers prevents over-etching of the superconducting layer and thus suppresses degradation of the critical current (Ic). By using the developed laser scribing process, we realized an improvement of processing speed and a reduction of Ic degradation at the same time. Subsequently, we developed reel-to-reel equipment to apply this process to coated conductors several hundred meters long. We succeeded in fabricating 280 m and 70 m long coated conductors with 5 mm width divided into three and five filaments, respectively. It was confirmed that they had one-third and one-fifth hysteresis loss, respectively, in comparison with that before processing, and high inter-filament resistance, over 0.1 MΩ cm. The typical degradation rates of Ic in the developed laser scribing process were less than 20%.

  8. Observation of the three-dimensional distribution of flux pinning centers in Dy-doped YBa2Cu3O7-x coated conductors

    NASA Astrophysics Data System (ADS)

    Herrera, M.; Ortalan, V.; Morgan, D. G.; Browning, N. D.; Rupich, M. W.

    2008-04-01

    The spatial distribution of flux pinning centers (such as defects, secondary phases, etc.) has a critical effect on the superconducting properties of YBa2Cu3O7-x (YBCO) coated conductors. To increase the flux pinning in coated conductors, impurities such as Dy can be intentionally added during processing to induce the formation of distributed insulating nanostructures. In this work, we show that the addition of Dy to a particular YBCO coated conductor gives rise to a high density of secondary nanoparticles of composition (YsDy1-s)2Cu2O5 with s ˜0.6. Using high-angle annular dark-field tomographic methods, the three-dimensional distribution of these insulating nanoparticles is determined. The size of the nanoparticles and the uniformity of their distribution are found to depend on their interaction with the grain boundary network within the YBCO layer. A bimodal distribution in the size of the particles is seen, where areas away from grain boundaries have a favorable uniform distribution of small particles (˜25 nm) while unfavorable isolated large particles 100-140 nm are seen to intersect the grain boundaries. A grain boundary diffusion model is proposed to account for the agglomeration of the small nanoparticles to form the large ones to the detriment of flux pinning within these local regions of the superconductor.

  9. Laser drilling: enhancing superconducting joint of GdBa2Cu3O7 - δ coated conductors

    NASA Astrophysics Data System (ADS)

    Park, Y. J.; Lee, M. W.; Oh, Y. K.; Lee, H. G.

    2014-08-01

    While GdBa2Cu3O7 - δ (GdBCO) coated conductors (CCs) have been proposed for superconducting applications, they have not been used in devices with persistent current mode (PCM) operation because of a lack of joining techniques. A superconducting joint of CCs, formed via melting diffusion and oxygenation annealing, offers no electrical resistance between the CCs, thus establishing a superconducting closed loop for PCM operation. Because superconductivity degrades with oxygen out-diffusion during melting diffusion, oxygenation annealing allows oxygen diffusion into the GdBCO lattices. As effective oxygenation annealing requires oxygen pathways in the joint, low solubility and diffusivity of oxygen in the buffer and CC substrate hinder full superconductivity recovery. Here we show a laser-drilling technique to produce microholes as conduits on the surfaces of GdBCO CCs’ to promote oxygen in-diffusion, which resulted in reduced superconductivity recovery time. Superconductivity was fully recovered after laser drilling, melting diffusion at 850 °C for 1 min, and oxygenation annealing at 500 °C for 350 h.

  10. Planar current anisotropy and field dependence of J c in coated conductors assessed by scanning Hall probe microscopy

    NASA Astrophysics Data System (ADS)

    Lao, M.; Hecher, J.; Sieger, M.; Pahlke, P.; Bauer, M.; Hühne, R.; Eisterer, M.

    2017-02-01

    The local distribution of the critical current density, J c, of coated conductors and YBa2Cu3O{}7-δ (YBCO) films on single crystalline substrate was investigated by scanning Hall probe microscopy. The high spatial resolution of the measurements enabled an assessment of dependence of the local J c on the local magnetic induction, B, and electric field, E. The derived J c(B)-dependence agreed well with the global J c obtained from magnetization loops and provided values of J c at very low fields, which are inaccessible to magnetization and transport measurements. The anisotropic current flow within the film plane was investigated in YBCO films on miscut SrTiO3 substrates and a GdBa2Cu3O{}7-δ film on an MgO buffer layer prepared by inclined substrate deposition on a Hastelloy substrate. The c-axis currents calculated from the Hall maps were significantly larger than previously reported data obtained from direct transport measurements. The planar current anisotropy at 77 K was found to be highly influenced by the microstructure which can either deteriorate the current flowing across the ab-planes or cause enhanced pinning and increase the critical current flowing parallel to the ab-planes.

  11. Reel-to-reel deposition of epitaxial double-sided MgO buffer layers for coated conductors

    NASA Astrophysics Data System (ADS)

    Xue, Yan; Xiong, Jie; Zhang, Yahui; Zhang, Fei; Zhao, Rui-Peng; Hui, Wang; Wang, Quiling; Cheng, Guo; Zhao, Xiao-Hui; Tao, Bo-Wan

    2016-06-01

    We have successfully employed a double-sided process to deposit MgO buffer layers on both sides of amorphous Y2O3 surface for double-sided YBa2Cu3O7-δ (YBCO) coated conductors (CCs) for the first time, the structure of which is of great prospect to improve the performance and cut the production cost. The biaxial textures of MgO buffer layer are noticeably affected by the ion energy and film thickness, which is demonstrated by X-ray diffraction. The best biaxial texture of double-sided MgO films shows ω-scan of (002) MgO and Φ-scan of (220) MgO yield full width at half maximum values of 4° and 7.8° for one side, respectively, as well as 3.5° and 6.7° for the other side. The subsequent double-sided YBCO films are deposited on the as-prepared MgO template with entire critical current of over 300 A/cm for both sides.

  12. Engineering of second generation HTS coated conductor architecture to enhance the normal zone propagation velocity in various operating conditions

    NASA Astrophysics Data System (ADS)

    Lacroix, C.; Sirois, F.; Fournier Lupien, J.-H.

    2017-06-01

    The effects of operating conditions, critical current and stabilizer geometry on the normal zone propagation velocity (NZPV) of second generation (2G) high-temperature superconductor (HTS) coated conductors (CCs) are investigated using finite element simulations. The NZPV of tapes with a low interfacial resistance between the HTS and stabilizer layers are first compared with tapes with a current flow diverter (CFD) architecture. Our results indicates that the CFD concept increases the NZPV for the whole range of operating temperatures investigated (10-77 K). In particular, for an operating temperature of 77 K and an operating current of 0.9I c, our numerical results indicate that the NZPV of a 2G HTS CC with a CFD architecture and a 2 μm thick stabilizer layer could reach a value of 50 m s-1. Furthermore, numerical simulations realized on the effect of the stabilizer geometry on the NZPV of 2G HTS CCs revealed that putting most of the stabilizer on the substrate side can enhance the NZPV by a factor of 7 or more, even for tape with thick stabilizer (20 μm or more). This is particularly promising for improving quench detection in applications requiring a thick stabilizer such as superconducting coils.

  13. First steps towards cube textured nickel profile wires for YBCO-coated conductors

    NASA Astrophysics Data System (ADS)

    Eickemeyer, J.; Güth, A.; Freudenberger, J.; Holzapfel, B.; Schultz, L.

    2011-10-01

    Cube textured nickel alloy tapes prepared by cold rolling and annealing (RABiTS method) represent a standard metallic substrate for superconductor coatings of the YBa 2Cu 3O 7-δ (YBCO) type. These tapes have a width to thickness ratio of about 30-100. However, a value of close to one is optimal concerning low energetic losses under alternating current applications. First experiments on micro-alloyed nickel prove that the cube texture as a typical sheet texture can also be formed in profile wires with a rectangular cross-section after cold drawing and recrystallization treatment.

  14. Thermal instability induced by high current densities in high-Tc coated conductors

    NASA Astrophysics Data System (ADS)

    Maza, J.; Ferro, G.; Veira, J. A.; Vidal, F.

    2013-10-01

    By using a 1 ms pulse technique, the current-voltage curves (CVC) under zero-applied magnetic field have been measured in practical high-Tc superconducting wires based on coated (RE)BCO. The measurements extend up to the so-called supercritical current intensity, I*, at which superconductivity disappears accompanied by an abrupt jump in the voltage. The resulting CVC, including the temperature dependence of I*, were analysed at a quantitative level in terms of a thermal instability model proposed recently. An attractive aspect of our thermal instability approach is that in spite of the complexity of the coated layered structure, in its simpler formulation all the geometric and thermal variables are encapsulated into a single characteristic parameter r with units of thermal resistance. All the experimental results for I* from 76 to 86 K are quantitatively, within 2%, accounted for by the thermal instability analysis. Furthermore, the best-fit value of r is found to be quite consistent with the inner geometry and composition of the wires. Another remarkable result of our analysis is that the temperature T* reached by the wire at I*, i.e., the temperature triggering the thermal runaway, is less than one kelvin above the bath temperature. These results further support the universality of the thermal instability mechanism of superconductivity quenching by high current densities.

  15. Highly cube textured Ni-W-RABiTS tapes for YBCO coated conductors

    NASA Astrophysics Data System (ADS)

    Eickemeyer, J.; Selbmann, D.; Opitz, R.; Wendrock, H.; Maher, E.; Miller, U.; Prusseit, W.

    2002-08-01

    The investigation of Ni-W alloys in the concentration range of solid solubility of tungsten in nickel proved the potential of this metallurgical system for rolling assisted biaxially textured substrate (RABiTS) tapes of high performance. The cube texture of Ni+5 at.%W was characterized by a maximum of the deviation frequency at about 4°. For this material the beneficial effect of the initial grain size on the final texture quality was shown. The YBCO (YBa 2Cu 3O 7- δ) type coatings on CeO 2 buffer layers carried absolute currents up to I=130 A at 77 K. A critical current density of jc=1.2 MA/cm 2 was achieved at 77 K and zero field on tapes up to 20 cm long.

  16. Insulation effect on thermal stability of Coated Conductors wires in liquid nitrogen

    NASA Astrophysics Data System (ADS)

    Rubeli, Thomas; Dutoit, Bertrand; Martynova, Irina; Makarevich, Artem; Molodyk, Alexander; Samoilenkov, Sergey

    2017-02-01

    Superconducting wires are not perfectly homogeneous in term of critical current as well as stabilization. In resistive fault current limiter applications this could lead to hot spots if the fault current is only slightly above the nominal current of the device. Increasing stabilization by using thicker silver coating for example may prevent this problem but this method implies longer wire length to maintain the same impedance during a fault. Very efficient cooling in another way to prevent hot spots, this can be achieved in nucleate boiling regime. Optimal insulation can be used to prevent film boiling regime, staying in nucleate boiling regime in a much broader temperature range. In this work a novel technique is used to monitor in real time the temperature of the wire during the quench. Using this method several increasing insulation thicknesses are tested, measuring for each the heat exchange rate to the nitrogen bath. Exchange rate measurements are made in quasistatic regime and during the re-cooling of the wire. SuperOx wires provided with different insulation thicknesses exhibit an excellent stability, far above a bare wire. On the other side, for very thick insulations the stability gain is lost. Re-cooling speeds dependency on insulation thicknesses is measured too.

  17. Fabrication of the cube textured NiO buffer layer by line-focused infrared heating for coated conductor application

    NASA Astrophysics Data System (ADS)

    Chung, Jun-Ki; Kim, Won-Jeong; Tak, Jinsung; Kim, Cheol Jin

    2007-10-01

    Epitaxial growth of NiO on the bi-axially textured Ni-3 at.%W (Ni-3W) substrate as seed layer for coated conductor were studied. The bi-axially textured NiO was formed on the Ni-3W tapes using a line-focused infrared heater by oxidizing the surface of the substrate at 800-950 °C for 15-120 s in oxygen atmosphere. The thickness of the NiO layer could be controlled by changing heat-treatment, which was estimated as approximately 200-500 nm in the cross-sectional SEM micrographs of the NiO/Ni template. This thickness is enough to block the diffusion of the Ni in the substrate to the superconducting layer. The samples showed strong texture development of NiO layer. The sample oxidized at 900 °C with the tape transferring speed of 30 mm/h exhibited ω-scan full width at half maximum (FWHM) values for Ni-3W(2 0 0) and NiO(2 0 0) were 3.97°, and 3.67°, and φ-scan FWHM values for Ni-3W(1 1 1) and NiO(1 1 1) were 9.58°, and 8.79°, respectively. Also, the (1 1 1) pole-figure of the NiO buffer layer showed the good symmetry of the four peaks, securing the epitaxial growth of the buffer layers on the NiO layer. Also NiO layer exhibited root-mean-square roughness value of 39 nm by AFM (10 × 10 μm) investigation.

  18. On-line characterization of YBCO coated conductors using Raman spectroscopy methods.

    SciTech Connect

    Maroni, V. A.; Reeves, J. L.; Schwab, G.; Chemical Engineering; SuperPower, Inc.

    2007-04-01

    The use of Raman spectroscopy for on-line monitoring of the production of superconducting YBa2Cu3O6+X (YBCO) thin films on long-length metal tapes coated with textured buffer layers is reported for the first time. A methodology is described for obtaining Raman spectra of YBCO on moving tape exiting a metal-organic-chemical-vapor-deposition (MOCVD) enclosure. After baseline correction, the spectra recorded in this way show the expected phonons of the specific YBCO crystal orientation required for high supercurrent transport, as well as phonons of non-superconducting second-phase impurities when present. It is also possible to distinguish YBCO films that are properly textured from films having domains of misoriented YBCO grains. An investigation of the need for focus control on moving tape indicated that focusing of the laser on the surface of the highly reflective YBCO films exiting the MOCVD enclosure tends to produce aberrant photon bursts that swamp the Raman spectrum. These photon bursts are very likely a consequence of optical speckle effects induced by a combination of surface roughness, crystallographic texture, and/or local strain within the small grain microstructure of the YBCO film. Maintaining a slightly out-of-focus condition provides the best signal-to-noise ratio in terms of the obtained Raman spectra. In addition to examining moving tape at the post-MOCVD stage, Raman spectra of the film surface can also be recorded after the oxygen anneal performed to bring the YBCO to the optimum superconducting state. Consideration is given to data processing methods that could be adapted to the on-line Raman spectra to allow the tagging of out-of-specification tape segments and, at a more advanced level, feedback control to the MOCVD process.

  19. Magnetisation and field quality of a cosine-theta dipole magnet wound with coated conductors for rotating gantry for hadron cancer therapy

    NASA Astrophysics Data System (ADS)

    Amemiya, Naoyuki; Sogabe, Yusuke; Sakashita, Masaki; Iwata, Yoshiyuki; Noda, Koji; Ogitsu, Toru; Ishii, Yusuke; Kurusu, Tsutomu

    2016-02-01

    Electromagnetic field analyses were carried out to study the influence of coated-conductor magnetisation, i.e. the screening (shielding) current, on the field quality of a dipole magnet in a rotating gantry for hadron cancer therapy. The analyses were made on the cross section of a cosine-theta dipole magnet in a rotating gantry for carbon ions, which generated 2.90 T of magnetic field. The temporal profile (temporal variation) of the magnet current was determined based on the actual excitation schemes of the magnets in the rotating gantry. The experimentally determined superconducting property of a coated conductor was considered, and we calculated the temporal evolutions of the current-density distributions in all the turns of coated conductors in the magnet. From the obtained current-density distributions, we calculated the multipole components of the magnetic field and evaluated the field quality of the magnet. The deviation in the dipole component from its designed value was up to approximately 25 mT, which was approximately 1% of the designed maximum dipole component. Its variation between repeated excitations was approximately 0.03%, and it drifted approximately 0.06% in 10 s. Some compensation schemes might be required to counteract such influence of magnetisation on the dipole component. Meanwhile, the higher multipole components were small, stable, and sufficiently reproducible for a magnet in rotating gantries, i.e. |b 3| ˜ 1.1 × 10-3 and |Δb 3| ˜ 0.2 × 10-3 in 10 s.

  20. Architecture for coated conductors

    DOEpatents

    Foltyn, Stephen R.; Arendt, Paul N.; Wang, Haiyan; Stan, Liliana

    2010-06-01

    Articles are provided including a base substrate having a layer of an oriented cubic oxide material with a rock-salt-like structure layer thereon, and, a layer of epitaxial titanium nitride upon the layer of an oriented cubic oxide material having a rock-salt-like structure. Such articles can further include thin films of high temperature superconductive oxides such as YBCO upon the layer of epitaxial titanium nitride or upon a intermediate buffer layer upon the layer of epitaxial titanium nitride.

  1. Plasmonic Three-Dimensional Transparent Conductor Based on Al-Doped Zinc Oxide-Coated Nanostructured Glass Using Atomic Layer Deposition

    SciTech Connect

    Malek, Gary A.; Aytug, Tolga; Liu, Qingfeng; Wu, Judy

    2015-04-02

    Transparent nanostructured glass coatings, fabricated on glass substrates, with a unique three-dimensional (3D) architecture were utilized as the foundation for the design of plasmonic 3D transparent conductors. Transformation of the non-conducting 3D structure to a conducting 3D network was accomplished through atomic layer deposition of aluminum-doped zinc oxide (AZO). After AZO growth, gold nanoparticles (AuNPs) were deposited by electronbeam evaporation to enhance light trapping and decrease the overall sheet resistance. Field emission scanning electron microscopy and atomic force microcopy images revealed the highly porous, nanostructured morphology of the AZO coated glass surface along with the in-plane dimensions of the deposited AuNPs. Sheet resistance measurements conducted on the coated samples verified that the electrical properties of the 3D network are comparable to that of the untextured two-dimensional AZO coated glass substrates. In addition, transmittance measurements of the glass samples coated with various AZO thicknesses showed preservation of the highly transparent nature of each sample, while the AuNPs demonstrated enhanced light scattering as well as light-trapping capability.

  2. Plasmonic Three-Dimensional Transparent Conductor Based on Al-Doped Zinc Oxide-Coated Nanostructured Glass Using Atomic Layer Deposition

    DOE PAGES

    Malek, Gary A.; Aytug, Tolga; Liu, Qingfeng; ...

    2015-04-02

    Transparent nanostructured glass coatings, fabricated on glass substrates, with a unique three-dimensional (3D) architecture were utilized as the foundation for the design of plasmonic 3D transparent conductors. Transformation of the non-conducting 3D structure to a conducting 3D network was accomplished through atomic layer deposition of aluminum-doped zinc oxide (AZO). After AZO growth, gold nanoparticles (AuNPs) were deposited by electronbeam evaporation to enhance light trapping and decrease the overall sheet resistance. Field emission scanning electron microscopy and atomic force microcopy images revealed the highly porous, nanostructured morphology of the AZO coated glass surface along with the in-plane dimensions of the depositedmore » AuNPs. Sheet resistance measurements conducted on the coated samples verified that the electrical properties of the 3D network are comparable to that of the untextured two-dimensional AZO coated glass substrates. In addition, transmittance measurements of the glass samples coated with various AZO thicknesses showed preservation of the highly transparent nature of each sample, while the AuNPs demonstrated enhanced light scattering as well as light-trapping capability.« less

  3. Conformal Coating of Three-Dimensional Nanostructures via Atomic Layer Deposition for Development of Advanced Energy Storage Devices and Plasmonic Transparent Conductors

    NASA Astrophysics Data System (ADS)

    Malek, Gary A.

    Due to the prodigious amount of electrical energy consumed throughout the world, there exists a great demand for new and improved methods of generating electrical energy in a clean and renewable manner as well as finding more effective ways to store it. This enormous task is of great interest to scientists and engineers, and much headway is being made by utilizing three-dimensional (3D) nanostructured materials. This work explores the application of two types of 3D nanostructured materials toward fabrication of advanced electrical energy storage and conversion devices. The first nanostructured material consists of vertically aligned carbon nanofibers. This three-dimensional structure is opaque, electrically conducting, and contains active sites along the outside of each fiber that are conducive to chemical reactions. Therefore, they make the perfect 3D conducting nanostructured substrate for advanced energy storage devices. In this work, the details for transforming vertically aligned carbon nanofiber arrays into core-shell structures via atomic layer deposition as well as into a mesoporous manganese oxide coated supercapacitor electrode are given. Another unique type of three-dimensional nanostructured substrate is nanotextured glass, which is transparent but non-conducting. Therefore, it can be converted to a 3D transparent conductor for possible application in photovoltaics if it can be conformally coated with a conducting material. This work details that transformation as well as the addition of plasmonic gold nanoparticles to complete the transition to a 3D plasmonic transparent conductor.

  4. Introduction of Artificial Pinning Center into PLD-YBCO Coated Conductor on IBAD and Self-Epitaxial CeO2 Buffered Metal Substrate

    SciTech Connect

    Kobayashi, H.; Yamada, Y.; Ishida, S.; Takahashi, K.; Konishi, M.; Ibi, A.; Miyata, S.; Kato, T.; Hirayama, T.; Shiohara, Y.

    2006-03-31

    In order to fabricate YBa2Cu3O7-x (YBCO) coated conductors with high critical current density Jc in magnetic fields, we fabricated YBCO coated conductors with artificial pinning centers by the pulsed laser deposition (PLD) method on a self epitaxial PLD-CeO2 layer and ion-beam assisted deposition (IBAD)-Gd2Zr2O7 (GZO) buffered Hastelloy tape. Artificial pinning centers were introduced by the PLD deposition using the yttria-stabilized zirconia (YSZ) oxide target (nano-dot method) and YBCO target including YSZ particles (mixed target method). In the experiments using YSZ oxide target, YSZ nano-dots were observed. They were approximately 15 nm in height and 10 nm to 70 nm in diameter. We found that the density of nano-dots was controlled by the number of laser pulses. These samples exhibited higher Jc than YBCO films in magnetic fields. Furthermore, a similar improvement of Jc was observed in the experiments using YBCO target including YSZ particles. TEM observation revealed that columnar nano-structure made of BaZrO3 was formed during YBCO deposition and it was effective for pinning. We call this new epitaxial nano-structure 'bamboo structure' from its anisotropic growth and morphology.

  5. Pursuing low joint resistivity in Cu-stabilized REBa2Cu3O δ coated conductor tapes by the ultrasonic weld-solder hybrid method

    NASA Astrophysics Data System (ADS)

    Shin, Hyung-Seop; Kim, Jong-min; Dedicatoria, Marlon J.

    2016-01-01

    Development of a coated conductor tape joint with good quality and low joint resistivity, R sj, in terms of transport and mechanical properties, was attempted by direct bonding at the interface of the Cu-Cu stabilizers in overlapped GdBCO CC tapes. In this study, we attempted to achieve a low R sj by introducing hybrid joining, soldering and ultrasonic welding (UW), and its mechanism was analyzed theoretically. Coated conductor tapes were experimentally joined using various methods of soldering, UW, and combinations of the two. As a result, a much lower R sj of about 57 nΩ · cm2 was obtained for RCE-DR-processed GdBCO CC tape joints using the hybrid joining method. The mechanical properties of the jointed CC tapes were also evaluated at room temperature and 77 K under self-field. Load-displacement curves of joined CC tapes followed the curve of the single CC tape. Critical current and joint resistance, R j, of hybrid-joined CC tape were retained after double bending at room temperature up to 20 mm bending diameter.

  6. Interactive modeling-synthesis-characterization approach towards controllable in situ self-assembly of artificial pinning centers in RE-123 films

    NASA Astrophysics Data System (ADS)

    Wu, Judy; Shi, Jack

    2017-10-01

    Raising critical current density J c in high temperature superconductors (HTSs) is an important strategy towards performance-cost balanced HTS technology for commercialization. The development of strong nanoscale artificial pinning centers (APCs) in HTS, such as YBa2Cu3O7 or RE-123 in general, represents one of the most exciting progressions in HTS material research in the last decade. Significantly raised J c has been demonstrated in APC/RE-123 nanocomposites by enhanced pinning on magnetic vortices in magnetic fields towards that demanded in practical applications. Among other processes, strain-mediated self-organization has been explored extensively for in situ formation of the APCs based on fundamental physics design rules. The desire in controlling the morphology, dimension, orientation, and concentration of APCs has led to a fundamental question on how strains interact in determining APCs at a macroscopic scale. Answering this question demands an interactive modeling-synthesis-characterization approach towards a thorough understanding of fundamental physics governing the strain-mediated self-organization of the APCs in the APC/RE-123 nanocomposites. Such an understanding is the key for a leap forward from the traditionally empirical method to materials-by-design to enable an optimal APC landscape to be achieved in epitaxial films of APC/YBCO nanocomposites under a precise guidance of fundamental physics. The paper intends to provide a review of recent progress made in the controllable generation of APCs using the interactive modeling-synthesis-characterization approach. The emphasis will be given to the understanding so far achieved using such an approach on the collective effect of the strain field on the morphology, dimension, and orientation of APCs in epitaxial APC/RE-123 nanocomposite films.

  7. ENSYSTROB - Design, manufacturing and test of a 3-phase resistive fault current limiter based on coated conductors for medium voltage application

    NASA Astrophysics Data System (ADS)

    Elschner, S.; Kudymow, A.; Brand, J.; Fink, S.; Goldacker, W.; Grilli, F.; Noe, M.; Vojenciak, M.; Hobl, A.; Bludau, M.; Jänke, C.; Krämer, S.; Bock, J.

    2012-11-01

    Within the German project ENSYSTROB a 3-phase resistive fault current limiter for medium voltage applications (12 kV, 533 Arms) was designed, built, tested and installed in the grid for a one year's field test. The superconducting modules are made of YBCO coated conductors and replace the modules of an already successfully tested limiter on the basis of BSCCO 2212 bulk material. The components are multifilar spirals equipped with pairs of 12 mm wide YBCO tapes. The single components were characterized with respect to critical current, AC losses and limitation behavior under all possible operation conditions. The finally mounted limiter was successfully tested with respect to high voltage and limitation according to the standards of the customer. It is now installed and operating in its field test location. Finally we give a first comparison of both materials with respect to the different operational aspects.

  8. Preparation of biaxially cube textured Ag, Cu-Au and Cu-Au-Ag films on Cu substrates for HTS coated conductor applications

    NASA Astrophysics Data System (ADS)

    Díaz, J.; Segarra, M.; Espiell, F.; Piñol, S.

    2001-08-01

    Copper (100) cube textured tapes have been covered successfully with biaxially textured thin and thick films of silver, gold and gold-silver by electrodeposition techniques for high temperature superconductors (HTS) coated conductor applications. The cube texture of Cu was promoted by recrystallization after smooth cold rolling. The biaxially cube textured Ag films were obtained by the electro-epitaxial deposition technique using no post-deposition heat treatment. Intermediate gold buffer layers were prepared in order to increase the thermal stability of the cube-textured Ag-buffered Cu substrates. The as-electrodeposited Au buffer layers were polycrystalline, but after an annealing treatment at high temperature the Au is absorbed by diffusion mechanism into the Cu tapes and a biaxially solid solution of Au-Cu(100) is formed on the surface. Ag thin films deposited on Cu-Au substrates form the same biaxial cube texture as the rolled Cu tapes after recrystallization at high temperature.

  9. Grain and grain-boundary critical currents in coated conductors with noncorrelating YBa2Cu3O7 and substrate grain-boundary networks

    NASA Astrophysics Data System (ADS)

    Palau, A.; Puig, T.; Obradors, X.; Feenstra, R.; Gapud, A. A.; Specht, E. D.; Feldmann, D. M.; Holesinger, T. G.

    2006-03-01

    The superconducting grain-boundary (GB) network of coated conductors (CCs) is usually assumed to be a replica of the substrate network. In this letter, we analyze IBAD and RABITS CCs, where such replica either do or do not exist. We have analyzed the effect of GB overgrowth on the critical currents by quantifying the average superconducting grain size and determining the intragrain and grain-boundary critical current densities, JcG and JcGB. We have employed a recently developed inductive methodology enabling the simultaneous determination of these three parameters. We show that the percolative JcGB may be reduced by 50% if the GB networks do not correlate, while JcG and the grain pinning properties appear unaffected.

  10. Conductor-polymer composite electrode materials

    DOEpatents

    Ginley, D.S.; Kurtz, S.R.; Smyrl, W.H.; Zeigler, J.M.

    1984-06-13

    A conductive composite material useful as an electrode, comprises a conductor and an organic polymer which is reversibly electrochemically dopable to change its electrical conductivity. Said polymer continuously surrounds the conductor in intimate electrical contact therewith and is prepared by electrochemical growth on said conductor or by reaction of its corresponding monomer(s) on said conductor which has been pre-impregnated or pre-coated with an activator for said polymerization. Amount of the conductor is sufficient to render the resultant composite electrically conductive even when the polymer is in an undoped insulating state.

  11. ALTERNATING CURRENT LOSSES IN AG-SHEATHED BSCCO (2212 AND 2223) TAPES AND WIRES AND YBCO (123) COATED CONDUCTORS

    SciTech Connect

    Dr. John S. Hurley

    2000-01-01

    In this study, we focus on the examination of ac losses in conductors utilizing Bi{sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O [BSCCO (2223)] high TC superconductors (HTS). In addition, we seek to assist other facilities such as the University of Wisconsin-Madison Applied Superconductivity Center (UW-ASC), Brookhaven National Laboratory, and other DoE facilities investigating the use of HTS in electric power applications (e.g., generators, motors, and transformers). To accomplish this we will develop an ac losses capability at Clark Atlanta University to complement the established ac losses efforts at Brookhaven National Laboratory (BSCCO) on BSCCO/Ag and various material characterization efforts taking place at the UW-ASC. Our goal is through this effort to gain a greater understanding of the effects on ac losses due to parameters such as ac/dc current, J{sub c}, tape geometry, voltage tap placement, field orientation, material anisotropy, surface irregularities, percolations and filament coupling effects. As a result, we expect to better understand how to minimize ac losses in applications requiring real or practical conductors. HTS conductors based on BSCCO-2223 are now being routinely produced in industrial lengths of high quality. Vendors such as Southwire and ASC are producing multi-filamentary tapes in lengths of 6 km or more carrying critical current densities of up to 3 kA/cm**2 at 77 K. While this is approaching the level of performance where some large-scale applications are considered to be economically viable, a number of problems remain to be solved. The remaining issues include: rapid reduction in JC in magnetic fields; and power dissipation due to varying magnetic fields or currents (ac losses).

  12. Magnetic and structural characterization of inkjet-printed TFAYBa2Cu3O7-x/MODCZO/ABADYSZ/SS coated conductors

    NASA Astrophysics Data System (ADS)

    Bartolomé, E.; Vlad, V. R.; Calleja, A.; Aklalouch, M.; Guzmán, R.; Arbiol, J.; Granados, X.; Palau, A.; Obradors, X.; Puig, T.; Usoskin, A.

    2013-12-01

    The superconductor industry is demanding new methodologies to manufacture km-long, high quality coated conductors at high growth rates, using cost-effective, scalable processes. We report on the fabrication by an all-chemical deposition method of highly textured, thick (0.9 μm) inkjet-printed YBCO films, using a Ce0.9Zr0.1O2 (CZO) capping layer deposited by MOD, on top of robust, buffered ABADYSZ/SS substrates. Thinner, 0.25 μm spin-coated YBCO films were also analyzed for comparison. The structural study performed by x-ray diffraction, optical, AFM, SEM and TEM microscopy demonstrates the success of the capping layer for enhancing the planarity of the as-received tape and obtaining highly homogeneous and well-textured YBCO films. DC magnetometry granularity analysis was used to determine the mean superconducting grain diameter, ˜2.5 μm, and the intra- and intergranular critical current densities of the coated conductors (CCs). For the thin, spin-coated sample, high self-field intragrain critical currents were measured ({J}_{{c}}^{{G}}=4 0, 3.3 MA cm-2 at 5, 77 K). For the thick, inkjet-printed tape {J}_{{c}}^{{G}} was reduced by ˜30%, but, notably, the percolative critical current, {J}_{{c}}^{{GB}}=1 2.5~{MA}~{{cm}}^{-2}, was only ˜10% smaller at 5 K, thanks to good preservation of the texture. At 77 K, {J}_{{c}}^{{GB}}=1.3~{MA}~{{cm}}^{-2} was achieved, implying a critical current of Ic = 117 A/cm-width. AC susceptibility measurements allowed us to demonstrate the high homogeneity of the fabricated CCs, and investigate the magnetic vortex-pinning phase diagram. Remarkably, the thick, inkjet-printed sample showed comparable irreversibility line (IL) and activation energy for thermal depinning, Ue(H), to the thin sample. The present results open new perspectives for the fabrication of high quality-to-cost ratio, all-chemical CCs with yet higher Ic values by inkjet printing multideposition of thicker YBCO layers.

  13. Electrochemical performance of Li-rich oxide composite material coated with Li0.75La0.42TiO3 ionic conductor

    NASA Astrophysics Data System (ADS)

    Yang, Chun-Chen; Liao, Pin-Ci; Wu, Yi-Shiuan; Lue, Shingjiang Jessie

    2017-03-01

    Li-rich (spray-dried (SP)-Li1.2Ni0.2Mn0.60O2) composite materials were prepared via two-step ball-mill and spray dry methods by using LiOH, α-MnO2, β-Ni(OH)2 raw materials. Two raw materials of α-MnO2 nanowires and microsphere β-Ni(OH)2 were synthesized by a hydrothermal process. In addition, Li0.75La0.42TiO3 (LLTO) fast ionic conductor was coated on SP-Li1.2Ni0.2Mn0.60O2 composite via a sol-gel method. The properties of the LLTO-coated SP-Li1.2Ni0.2Mn0.60O2 composites were determined by X-ray diffraction, scanning electron microscopy, micro-Raman, XPS, and the AC impedance method. The discharge capacities of 1 wt.%-LLTO-coated SP-Li1.2Ni0.2Mn0.60O2 composites were 256, 250, 231, 200, 158, and 114 mAh g-1 at rates of 0.1, 0.2, 0.5, 1, 3, and 5C, respectively, in the voltage range 2.0-4.8 V. The 1 wt.%-LLTO-coated Li-rich oxide composite showed the discharge capacities of up to 256 mAh g-1 in the first cycle at 0.1C. After 30 cycles, the discharge capacity of 244 mAh g-1 was obtained, which showed the capacity retention of 95.4%.

  14. Flexible, Polymer-Filled Metallic Conductors

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A.; Swec, Diane M.

    1989-01-01

    Procedure developed to make materials both flexible and reasonably good electrical conductors. Metal or polymer sheet substrate cleaned with beam of energetic inert-gas ions to remove adsorbed gases and contaminants from surface. After cleaning, substrate coated by cosputter deposition of both conductive metal and flexible polymer. Removed by either mechanical or chemical-dissolution technique, and resulting flexible metal/polymer conductor bonded at low temperature to conductor-surface contacts.

  15. Flexible, Polymer-Filled Metallic Conductors

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A.; Swec, Diane M.

    1989-01-01

    Procedure developed to make materials both flexible and reasonably good electrical conductors. Metal or polymer sheet substrate cleaned with beam of energetic inert-gas ions to remove adsorbed gases and contaminants from surface. After cleaning, substrate coated by cosputter deposition of both conductive metal and flexible polymer. Removed by either mechanical or chemical-dissolution technique, and resulting flexible metal/polymer conductor bonded at low temperature to conductor-surface contacts.

  16. Development of cube textured Ni 5at.%W alloy substrates for YBCO coated conductor application using a powder metallurgy process

    NASA Astrophysics Data System (ADS)

    Kim, S.-S.; Tak, J.-S.; Bae, S.-Y.; Chung, J.-K.; Ahn, I.-S.; Kim, C.-J.; Kim, K.-W.; Cho, K.-K.

    2007-10-01

    In this paper, Ni-5at.%W alloy substrate for YBCO coated conductor was fabricated by a dry powder metallurgy process including powder compaction, cold isostatic pressing (CIP), cold rolling and annealing for recrystallization. Ni and W powders were ball-milled at this process for various times of 10, 30, 50 and 100 h in argon atmosphere. The rod-like Ni-W alloy compacts were sintered at 1150 °C for 1 h in 96%Ar-4%H2 atmosphere. The sintered rods were cold rolling into thin tape of 70-90 μm thickness with 5% reduction at each path. The Ni-W alloy tapes were annealed at 800-1200 °C in an atmosphere of 96%Ar-4%H2 mixing gas for the development of cube texture. The tape with the best properties of low surface roughness, small grain size and strong cube texture was obtained at the condition annealed at 1200 °C using ball-milled powder for 30 min. The W addition to Ni improved the mechanical properties by solid solution hardening and inhibited grain growth for annealing heat treatment. The tapes were characterized by X-ray pole-figure, optical microscopy (OM), scanning electron microscopy (SEM) and scanning probe microscopy (SPM).

  17. Development of cube textured Ni W alloy tapes using powder metallurgy along with high energy ball milling for HTS coated conductors

    NASA Astrophysics Data System (ADS)

    Zhou, Y. X.; Naguib, R.; Fang, H.; Salama, K.

    2004-07-01

    Ni based alloys have received considerable attention as the substrates for HTS coated conductors due to improved mechanical properties and reduced magnetization. Powder metallurgy is one of the promising processes for the fabrication of long alloy textured substrates. In this paper, Ni-3 at.% W alloy substrates were prepared by using high purity metal powders as starting materials. The Ni and 3 at.% W powder mixture was high energy ball milled for different periods, isostatically pressed, sintered, rolled and texture annealed. The high energy ball milling process made the powders mix uniformly and the grain sizes decrease significantly, which led to higher boundary energy and residual strain energy. The longer ball milling period resulted in a finer grain size and sharper texture in the substrate, which were confirmed by EBSD and SEM analysis. SEM and AFM observations indicate the surface of textured Ni-3 at.% W substrates is smooth and the roughness value (Rrms) is about 1.126 nm, which is suitable for deposition of buffer layers.

  18. The influence of grain boundary I c on the macroscopic strain effect of I c in BHO-doped GdBCO-coated conductors

    NASA Astrophysics Data System (ADS)

    Usami, Takashi; Ichino, Yusuke; Yoshida, Yutaka; Sugano, Michinaka; Ibi, Akira; Izumi, Teruo

    2016-07-01

    The effect of strain in REBa2Cu3O y (REBCO: RE = Y, Gd, Sm, Eu) coated conductors (CCs) on the critical current (I c) is one of the most fundamental factors for superconducting coil applications because CCs experience a variety of stresses. In this study, we carried out bending tests and measured the peak strain and the strain sensitivity of I c (a-value) for GdBCO CCs at 77 K under self-field. These values were evaluated for pure GdBCO CCs and BaHfO3 BHO-doped GdBCO CCs, which had oxide buffer layers with varying in-plane grain alignments of the CeO2 top layer. As a result, the peak strains and a-values for the BHO-doped GdBCO CCs depended on the FWHM of the CeO2 220 reflection in the φ-scan profile (Δφ), and decreased monotonically with decreasing Δφ. On the other hand, the peak strain and a-value were nearly independent of Δφ in the pure-GdBCO CCs. The change in peak strains for the BHO-doped GdBCO CCs are discussed on the basis of the relative contribution of intra-grain I c and inter-grain I c to the macroscopic strain effect of I c in the CCs.

  19. Characterizing transport current defects in 1-cm-wide YBa[sub 2]Cu[sub 3]O[sub 7-delta] coated conductors.

    SciTech Connect

    Brown, G. W.; Hawley, M. E.; Peterson, E. J.; Coulter, J. Y.; Dowden, P. C.; Arendt, P. N.; Foltyn, S. R.; Mueller, F. M.

    2001-01-01

    We have used a low temperature magnetic imaging system to determine current pathways in 5 cm long 'good' and 'bad' regions of a 1-cm-wide YBa2Cu3O7-{delta} coated conductor. The good and bad regions were identified with 4 point probe measurements taken at 1 cm intervals along the tape length. The current density map from the good region showed the expected edge peaked structure, similar to that seen in previous work on high quality test samples grown on single crystal substrates. The structure was also consistent with theoretical understanding of thin film superconductors where demagnetizing effects are strong. The maps from the bad region showed that the current was primarily confined to the right half of the sample. The left half carried only a small current that reached saturation quickly. Effectively halving the sample width quantitatively explains the critical current measured in that section. Spatially resolved xray analysis with 1 mm resolution was used to further characterize the bad section and suggested an abnormally large amount of a-axis YBCO present. This may be the result of non-uniform heating leading to a low deposition temperature in that area.

  20. Decoupling and tuning competing effects of different types of defects on flux creep in irradiated YBa2Cu3O7-δ coated conductors

    NASA Astrophysics Data System (ADS)

    Eley, S.; Leroux, M.; Rupich, M. W.; Miller, D. J.; Sheng, H.; Niraula, P. M.; Kayani, A.; Welp, U.; Kwok, W.-K.; Civale, L.

    2017-01-01

    YBa2Cu3O7-δ coated conductors (CCs) have achieved high critical current densities (J c) that can be further increased through the introduction of additional defects using particle irradiation. However, these gains are accompanied by increases in the flux creep rate, a manifestation of competition between the different types of defects. Here, we study this competition to better understand how to design pinning landscapes that simultaneously increase J c and reduce creep. CCs grown by metal organic deposition show non-monotonic changes in the temperature-dependent creep rate, S(T). Notably, in low fields, there is a conspicuous dip to low S as the temperature (T) increases from ˜20 to ˜65 K. Oxygen-, proton-, and Au-irradiation substantially increase S in this temperature range. Focusing on an oxygen-irradiated CC, we investigate the contribution of different types of irradiation-induced defects to the flux creep rate. Specifically, we study S(T) as we tune the relative density of point defects to larger defects by annealing both an as-grown and an irradiated CC in O2 at temperatures T A = 250 °C-600 °C. We observe a steady decrease in S(T > 20 K) with increasing T A, unveiling the role of pre-existing nanoparticle precipitates in creating the dip in S(T) and point defects and clusters in increasing S at intermediate temperatures.

  1. HTS planar gradiometer consisting of SQUID with multi-turn input coil and large pickup coil made of GdBCO coated conductor

    NASA Astrophysics Data System (ADS)

    Tsukamoto, Akira; Adachi, Seiji; Oshikubo, Yasuo; Hato, Tsunehiro; Enpuku, Keiji; Sugisaki, Masaki; Arai, Eiichi; Tanabe, Keiichi

    2013-01-01

    We have investigated the fabrication of a high-temperature superconducting (HTS) gradiometer with long baseline for geophysical applications. The proof-of-concept gradiometer using a 1-turn pickup coil made of a GdBa2Cu3Oy coated conductor (GCC) and 5.5-turn input coil integrated on a SQUID was fabricated in our previous work. In this study, we have optimized the device structure to improve the frequency response, gradient field sensitivity and gradiometer balance. The fabricated flux transformer consists of a 6-turn planar gradiometric pickup coil and a 26-turn input coil made of an HTS thin film. A low-melting-point alloy was used to connect polished Ag surfaces of the CGG pickup coil and Au pads of the input coil. An HTS SQUID was formed on another substrate and stacked on the input coil. A mechanical balancing structure using three pieces of GCC as a superconducting shield was also implemented. The fabricated gradiometer showed a gradient field noise of 0.8 fT/cm Hz1/2 in the white noise regions, a gradiometer balance of 1/142, and a cutoff frequency of 9 Hz corresponding to a 2 mΩ contact resistance between the pickup coil and the input coil.

  2. Experimental and numerical study of frequency-dependent transport loss in YBa2Cu3O7-δ coated conductors with ferromagnetic substrate and copper stabilizer

    NASA Astrophysics Data System (ADS)

    Liu, Guole; Zhang, Guomin; Yu, Hui; Jing, Liwei; Ai, Liwang; Liu, Qi

    2017-06-01

    Although AC transport losses of YBa2Cu3O7-δ (YBCO) coated conductors (CCs) have been studied extensively, the frequency dependence of transport losses still needs more investigations. This paper presents a study on the frequency dependence (in the range of 50-1000 Hz) of the transport losses in YBCO CCs with ferromagnetic substrate and copper stabilizer by the use of both experimental and finite element methods (FEMs). The finite element model (FEM) is based on H-formulation and E-J power law, and calculated AC transport losses accord with the experimental ones. The contributions of ferromagnetic (Ni-5at.%W substrate), eddy current (conventional metal), and hysteresis (superconducting YBCO) losses are extracted. It is shown that the AC transport loss per cycle increases with the frequency due to the growing contribution of eddy current loss. More than 80% of eddy current loss comes from the copper stabilizer adjacent to the ferromagnetic substrate. The influence of magnetic substrate on AC loss is also studied, and it is found that YBCO CCs with non-magnetic substrates are more suitable for high-frequency applications.

  3. Simulation and experiments of stacks of high temperature superconducting coated conductors magnetized by pulsed field magnetization with multi-pulse technique

    NASA Astrophysics Data System (ADS)

    Zou, Shengnan; Zermeño, Víctor M. R.; Baskys, A.; Patel, A.; Grilli, Francesco; Glowacki, B. A.

    2017-01-01

    High temperature superconducting bulks or stacks of coated conductors (CCs) can be magnetized to become trapped field magnets (TFMs). The magnetic fields of such TFMs can break the limitation of conventional magnets (<2 T), so they show potential for improving the performance of many electrical applications that use permanent magnets like rotating machines. Towards practical or commercial use of TFMs, effective in situ magnetization is one of the key issues. The pulsed field magnetization (PFM) is among the most promising magnetization methods in virtue of its compactness, mobility and low cost. However, due to the heat generation during the magnetization, the trapped field and flux acquired by PFM usually cannot achieve the full potential of a sample (acquired by the field cooling or zero field cooling method). The multi-pulse technique was found to effectively improve the trapped field by PFM in practice. In this work, a systematic study on the PFM with successive pulses is presented. A 2D electromagnetic-thermal coupled model with comprehensive temperature dependent parameters is used to simulate a stack of CCs magnetized by successive magnetic pulses. An overall picture is built to show how the trapped field and flux evolve with different pulse sequences and the evolution patterns are analyzed. Based on the discussion, an operable magnetization strategy of PFM with successive pulses is suggested to provide more trapped field and flux. Finally, experimental results of a stack of CCs magnetized by typical pulse sequences are presented for demonstration.

  4. Development of Biaxially Textured YBa{sub 2}Cu{sub 3}O{sub 7} Coated Conductors in the U.S.

    SciTech Connect

    Christen, D.K.; Hawsey, R.A.; Kroeger, D.M.

    1999-11-13

    Two new processes have been under development since 1991 that promise a new, cost-effective way to manufacture flexible, high current density wires made from YBa{sub 2}Cu{sub 3}O{sub 7} (YBCO). The key is to prepare a textured substrate, or ''template,'' on which the YBCO may be deposited as a biaxially aligned thick film. Ion beam assisted deposition (IBAD) of yttria stabilized zirconia or magnesium oxide on alloy tapes enables a final superconducting layer with grain-to-grain, in-plane alignment to within 3-5 degrees. Similar results are achieved on rolling-assisted, biaxially textured substrates (RABiTS) using a variety of oxide layers on textured nickel tapes. The performance of research lengths of prototype wires in strong magnetic fields at 65 K already exceeds that of NbTi and Nb{sub 3}Sn in liquid helium. A scalable, ex-situ process for the YBCO coating has been demonstrated on both types of substrates. Consistent values of critical current density (J{sub c }) greater than 1 x 10{sup 6} A/cm{sup 2} are now obtained on RABiTS, and J{sub c}'s in excess of 2 x 10{sup 6} A/cm{sup 2} have been obtained on both substrates. A nonmagnetic variation of RABiTS (Ni-13% Cr) has also been shown to yield Jc greater than 1.5 x 10{sup 6} A/cm{sup 2} . Six private companies in the U.S. are scaling up YBCO coated conductors for power and physics applications.

  5. Spray coating of crack templates for the fabrication of transparent conductors and heaters on flat and curved surfaces.

    PubMed

    Gupta, Ritu; Rao, K D M; Srivastava, Kartikeya; Kumar, Ankush; Kiruthika, S; Kulkarni, Giridhar U

    2014-08-27

    Transparent conducting electrodes (TCEs) have been made on flat, flexible, and curved surfaces, following a crack template method in which a desired surface was uniformly spray-coated with a crackle precursor (CP) and metal (Ag) was deposited by vacuum evaporation. An acrylic resin (CP1) and a SiO2 nanoparticle-based dispersion (CP2) derived from commercial products served as CPs to produce U-shaped cracks in highly interconnected networks. The crack width and the density could be controlled by varying the spray conditions, resulting in varying template thicknesses. By depositing Ag in the crack regions of the templates, we have successfully produced Ag wire network TCEs on flat-flexible PET sheets, cylindrical glass tube, flask and lens surface with transmittance up to 86%, sheet resistance below 11 Ω/□ for electrothermal application. When used as a transparent heater by joule heating of the Ag network, AgCP1 and AgCP2 on PET showed high thermal resistance values of 515 and 409 °C cm(2)/W, respectively, with fast response (<20 s), requiring only low voltages (<5 V) to achieve uniform temperatures of ∼100 °C across large areas. Similar was the performance of the transparent heater on curved glass surfaces. Spray coating in the context of crack template is a powerful method for producing transparent heaters, which is shown for the first time in this work. AgCP1 with an invisible wire network is suited for use in proximity while AgCP2 wire network is ideal for use in large area displays viewed from a distance. Both exhibited excellent defrosting performance, even at cryogenic temperatures.

  6. Surface oxidation of cube-textured Ni-Cr for the formation of a NiO buffer layer for superconducting coated conductors

    NASA Astrophysics Data System (ADS)

    Lockman, Z.; Qi, X.; Berenov, A.; Goldacker, W.; Nast, R.; deBoer, B.; Holzapfel, B.; MacManus-Driscoll, J. L.

    2002-12-01

    The surface oxidation epitaxy behaviour of the rolling assisted biaxially textured substrates of cube-textured Ni-10%Cr and Ni-13%Cr foils were investigated, in air, at 1050 °C. For both alloys, the optimum out-of-plane texture of cube oriented NiO was obtained for the shortest oxidation times, t, of a few minutes, although a strong texture still remained for longer times. For t<40 min, the NiO layer showed both 0° and 45° in-plane orientations with respect to the underlying Ni-Cr, whereas for t⩾40 min, a single, 45° in-plane orientation was observed. The surface roughness of the NiO layer was the lowest after ∼10-40 min oxidation. For oxidation times longer than 40 min, the macroscopic NiO roughness (mm 2 scale) increased dramatically due to a festooning effect. A fully connected Cr 2O 3 layer formed at the interface between the Ni and NiO for even the shortest oxidation times (few minutes). The Cr 2O 3 layer acted as a diffusion barrier to Ni, and limited the thickness of the surface NiO to a few microns, almost independent of oxidation time. The surface NiO layer showed better adherence to the Ni-10%Cr than to the Ni-13%Cr. For superconducting coated conductor applications, the optimum NiO buffer layer is formed on Ni-10%Cr foil after oxidation at 1050 °C for ∼40 min. The important columnar surface layer is ∼ 7 μm thick, is highly textured with an r.m.s. surface roughness of ∼200 nm on a mm 2 scale, and ∼100 nm on the scale of the grain size. The layer shows good adherence to the underlying Cr 2O 3/Ni-Cr.

  7. Buffer layers for coated conductors

    DOEpatents

    Stan, Liliana; Jia, Quanxi; Foltyn, Stephen R.

    2011-08-23

    A composite structure is provided including a base substrate, an IBAD oriented material upon the base substrate, and a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates upon the IBAD oriented material. Additionally, an article is provided including a base substrate, an IBAD oriented material upon the base substrate, a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates upon the IBAD oriented material, and a thick film upon the cubic metal oxide material. Finally, a superconducting article is provided including a base substrate, an IBAD oriented material upon the base substrate, a cubic metal oxide material selected from the group consisting of rare earth zirconates and rare earth hafnates upon the IBAD oriented material, and an yttrium barium copper oxide material upon the cubic metal oxide material.

  8. Microstructural investigation of phases and pinning properties in MBa2Cu3O7-x (M = Y and/or Gd) coated conductors produced by scale-up facilitie

    NASA Astrophysics Data System (ADS)

    Jin, Hye-Jin; Moon, Han-Kyoul; Yoon, Seokhyun; Jo, William; Kim, Kunsu; Kim, Miyoung; Ko, Rock-Kil; Jo, Young-Sik; Ha, Dong-Woo

    2016-03-01

    To expedite the commercialization of coated conductors, a robust stacking architecture of the wires must be developed and the performance of the critical currents improved. More importantly, the manufacturability, or large-scale delivery, and the capability of sustaining production at a high rate must be considered. The products of three companies, American Superconductor, Superpower Inc., and SuNAM Co., Ltd, were selected because these companies have announced commercial-grade production lines and delivered a significant amounts of wires to the open market that meet the standards demanded by power devices. X-ray diffraction patterns were used to verify the structural properties and the phase formation in the wires, and transmission electron microscopy with energy dispersive spectroscopy was used to investigate the microstructure and composition of the conductors. In addition, Raman scattering spectroscopy was used for the analysis of the phase formation and for the elucidation of secondary phases in the superconducting layers. The field dependence of the critical current was also studied to compare the transport characteristics under relatively low and medium magnetic field at 77 K and 60 K. Pinning forces were obtained from the field dependence of transport properties and pinning characteristics were investigated. The theoretical and experimental analyses were combined together using the Dew-Hughes formula to extract the scaling exponents and estimate the irreversibility lines of the fields. The results showed that the three conductors possess pinning mechanisms that originate from core pinning with a surface pinning geometry. It is remarkable that the wires discussed in this paper exhibit very similar pinning characteristics even though they have different characteristics in terms of chemical composition, microstructure, stacking architectures, and distribution of parasitic phases.

  9. Stretchable, transparent, ionic conductors.

    PubMed

    Keplinger, Christoph; Sun, Jeong-Yun; Foo, Choon Chiang; Rothemund, Philipp; Whitesides, George M; Suo, Zhigang

    2013-08-30

    Existing stretchable, transparent conductors are mostly electronic conductors. They limit the performance of interconnects, sensors, and actuators as components of stretchable electronics and soft machines. We describe a class of devices enabled by ionic conductors that are highly stretchable, fully transparent to light of all colors, and capable of operation at frequencies beyond 10 kilohertz and voltages above 10 kilovolts. We demonstrate a transparent actuator that can generate large strains and a transparent loudspeaker that produces sound over the entire audible range. The electromechanical transduction is achieved without electrochemical reaction. The ionic conductors have higher resistivity than many electronic conductors; however, when large stretchability and high transmittance are required, the ionic conductors have lower sheet resistance than all existing electronic conductors.

  10. Selective oxidation of cube textured Ni and Ni-Cr substrate for the formation of cube textured NiO as a component buffer layer for REBa 2Cu 3O 7+ x (REBCO) coated conductors

    NASA Astrophysics Data System (ADS)

    Lockman, Z.; Goldacker, W.; Nast, R.; deBoer, B.; MacManus-Driscoll, J. L.

    2002-08-01

    Thermal oxidation of cube textured, pure Ni and Ni-Cr tapes was undertaken under different oxidation conditions to form cube textured NiO for the use as a first component of buffer layer for the coated conductor. Cube textured NiO was formed on pure Ni after oxidising for more than 130 min in O 2 at 1250 °C. The oxide thickness was >30 μm. Much shorter oxidation times (20-40 min, NiO thickness of ∼5 μm) and lower temperature (1050 °C) were required to form a similar texture on Ni-Cr foils. In addition, NiO formed on Ni-13%Cr was more highly textured than Ni-10%Cr. A Cr 2O 3 inner layer and NiO outer layer was formed on the Ni-Cr alloys.

  11. Conductor requirements for high-temperature superconducting utility power transformers

    SciTech Connect

    Pleva, E. F.; Mehrotra, V.; Schwenterly, S W

    2010-01-01

    High-temperature superconducting (HTS) coated conductors in utility power transformers must satisfy a set of operating requirements that are driven by two major considerations-HTS transformers must be economically competitive with conventional units, and the conductor must be robust enough to be used in a commercial manufacturing environment. The transformer design and manufacturing process will be described in order to highlight the various requirements that it imposes on the HTS conductor. Spreadsheet estimates of HTS transformer costs allow estimates of the conductor cost required for an HTS transformer to be competitive with a similarly performing conventional unit.

  12. Thunderclouds and Lightning Conductors

    ERIC Educational Resources Information Center

    Martin, P. F.

    1973-01-01

    Discusses the historical background of the development of lightning conductors, describes the nature of thunderclouds and the lightning flash, and provides a calculation of the electric field under a thundercloud. Also discussed are point discharge currents and the attraction theory of the lightning conductor. (JR)

  13. Thunderclouds and Lightning Conductors

    ERIC Educational Resources Information Center

    Martin, P. F.

    1973-01-01

    Discusses the historical background of the development of lightning conductors, describes the nature of thunderclouds and the lightning flash, and provides a calculation of the electric field under a thundercloud. Also discussed are point discharge currents and the attraction theory of the lightning conductor. (JR)

  14. An all chemical solution deposition approach for the growth of highly textured CeO2 cap layers on La2Zr2O7-buffered long lengths of biaxially textured Ni W substrates for YBCO-coated conductors

    NASA Astrophysics Data System (ADS)

    Engel, S.; Knoth, K.; Hühne, R.; Schultz, L.; Holzapfel, B.

    2005-10-01

    A reel-to-reel, dip coating process has been developed to continuously deposit epitaxial La2Zr2O7 (LZO) and CeO2 on 5 m long cube-textured {100} (001)Ni tapes. Recent results for La2Zr2O7 and CeO2 buffer layers deposited on long lengths of Ni substrate for the realization of YBa2Cu3O7-x (YBCO)-coated conductors are presented. The major achievement is the development of a new all chemical solution deposition (CSD) process leading to the formation of highly textured buffer layers at moderate annealing temperatures. Reproducible highly textured, dense and crack-free LZO buffer layers and CeO2 cap layers were obtained for annealing temperatures as low as 900 °C in a reducing atmosphere (Ar-5 at.%-H2). The thickness of the LZO buffer layers was determined to be (200 ± 10) nm per single coating; prepared cerium oxide layers showed a thickness of 60 nm ± 10 nm. Pulsed laser deposition (PLD) was used to grow YBCO films on these substrates. A Tc 0 of T = 90.5 K and ΔTc = 1.4 K was obtained on PLD-YBCO/CSD-CeO2 /CSD-LZO/Ni-5 at.% W, which shows the outstanding features of this new buffer layer architecture processed by CSD. The large layer thickness combined with low annealing temperatures is the main advantage of this new process for low-cost buffer layer deposition on Ni-RABiTS (rolling-assisted biaxially textured substrates).

  15. Dependencies of dynamical magnetic losses in conductor-coated dielectric particles on radius of dielectric core, thickness and conductivity of conductive shell

    NASA Astrophysics Data System (ADS)

    Anzulevich, Anton; Butko, Leonid; Bychkov, Igor; Kalganov, Dmitry; Pavlov, Dmitry; Moiseev, Sergey

    2017-09-01

    In this work, we modeled dielectric spherical particles covered by metallic layer. We obtained dependencies of real and imaginary parts of the effective permittivity and permeability of powders from metalized dielectric particles on the frequency, radius and permittivity of the particle, thickness and conductivity of the metallic layer. We used finite element method for calculation of the electromagnetic fields in the investigated model and combination of impedance lows for ideal conductor and ideal magnetic mirror to calculate effective electrodynamics parameters. Novel technique for calculation of effective permittivity and permeability from results of direct calculations of electromagnetic fields in the model is provided in this paper. The imaginary part of the effective permeability is large enough compared with imaginary part of the effective permittivity and reaches its maximum values at the thickness of the metallic layer less than the skin depth. Therefore, microwave heating of such particles is due to dynamic magnetic losses. Moreover, the imaginary part of the effective permeability for metallized dielectric particles can be nearly twice greater than the one for entire conductive particles.

  16. The role of a-axis grains in the transition to the normal state of YBa{sub 2}Cu{sub 3}O{sub 7−δ} films and of 2G-coated conductors when induced by high electrical current densities

    SciTech Connect

    Bernstein, P. Harnois, C.; Mc Loughlin, C.; Noudem, J.; Thimont, Y.; Ferro, G.; Osorio, M. R.; Veira, J. A.; Vidal, D.; Vidal, F.

    2014-02-07

    The influence of surface defects, in particular of a-axis grains, on the transition to the normal state induced by high current densities in YBa{sub 2}Cu{sub 3}O{sub 7−δ} (YBCO) thin films and in a commercial 2G-coated conductor is investigated. For that purpose, the surface of the samples is observed by scanning electron microscopy and isothermal current-voltage curves are measured at different temperatures with pulsed currents up to the quenching value I*. The results show that the ratio of I* to the critical current is large if a-axis grains are not visible at the surface of the YBCO films, while it is much lower if the surface includes a-axis grains as this is the case for the coated conductor. The connection between the transition onset and the vortex dynamics, as well as the role of the a-axis grains in this process are discussed. The relation between the I* values obtained from thermal calculations and those resulting from vortex dynamics considerations is also discussed, as well as the possible consequences suggested by this work for the different applications of the coated conductors.

  17. Strong influence of the oxygen stoichiometry on the vortex bundle size and critical current densities J c of GdBa2Cu3O x -coated conductors grown by co-evaporation

    NASA Astrophysics Data System (ADS)

    Haberkorn, N.; Guimpel, J.; Suárez, S.; Troiani, H.; Granell, P.; Golmar, F.; Lee, Jae-Hun; Moon, S. H.; Lee, Hunju

    2017-09-01

    We report on the influence of oxygen stoichiometry on the vortex creep mechanism of GdBa2Cu3O x -coated conductors produced by co-evaporation. The oxygen stoichiometry of the films, x, was modified in a controlled way between 6.85 and 7, which resulted in systematic and reversible control of the superconducting critical temperature between about 78 and 93 K. The change in the oxygen stoichiometry produces a strong reduction in the self-field critical current densities J c without significantly modifying the power-law dependence at intermediate magnetic fields, which indicates a negligible contribution of oxygen vacancies to the pinning. In addition, the characteristic glassy exponent μ shows a systematic diminution from about 1.63 at x = 7 to about 1.12 at x = 6.85. The results are compared with those obtained for proton- and oxygen-irradiated films, in which the vortex dynamics is determined by a balance between the improved pinning, originating from nanocluster inclusion, and the suppressed superconducting properties due to disorder in the nanoscale.

  18. Miniaturization of BaHfO3 nanoparticles in YBa2Cu3O y -coated conductors using a two-step heating process in the TFA-MOD method

    NASA Astrophysics Data System (ADS)

    Horita, H.; Teranishi, R.; Yamada, Kazuhiro; Kaneko, K.; Sato, Y.; Otaguro, K.; Nishiyama, T.; Izumi, T.; Awaji, S.

    2017-02-01

    The critical current density (J c) of YBa2Cu3Oy (YBCO)-coated conductors in a magnetic field can be enhanced by the doping of flux-pinning centers in a metal organic deposition (MOD) process with trifluoroacetates (TFA). The size of these flux-pinning centers should be less than 10 nm to achieve commercial use due to the coherence length of YBCO at 77 K. In this paper, BaHfO3 (BHO) nanoparticles were introduced into YBCO films using the TFA-MOD method. Microstructures and the J c properties of the films prepared using a two-step heating process at crystallization were compared with film prepared using a conventional one-step heating process. The two-step heating process produced 15 nm average-sized BHO nanoparticles in the film compared to 19 nm nanoparticles in a film prepared using a one-step process. It was revealed that the size of nanoparticles in the films could be miniaturized by improving the heating processes in the MOD method, and the miniaturized nanoparticles could contribute to increased J c in magnetic fields. The mechanism of miniaturization is also discussed based on microstructure observations of quenched films.

  19. Fabrication and characterization of La2Zr2O7 films on different buffer architectures for YBa2Cu3O7-δ coated conductors by RF magnetron sputtering.

    PubMed

    Xu, Da; Liu, Linfei; Xiao, Guina; Li, Yijie

    2013-02-27

    La2Zr2O7 (LZO) films were grown on different buffer architectures by radio frequency magnetron sputtering for the large-scale application of YBa2Cu3O7-x (YBCO)-coated conductors. The three different buffer architectures were cerium oxide (CeO2), yttria-stabilized zirconia (YSZ)/CeO2, and CeO2/YSZ/CeO2. The microstructure and surface morphology of the LZO film were studied by X-ray diffraction, optical microscopy, field emission scanning electron microscopy, and atomic force microscopy. The LZO films prepared on the CeO2, YSZ/CeO2, and CeO2/YSZ/CeO2 buffer architectures were preferentially c-axis-oriented and highly textured. The in-plane texture of LZO film on CeO2 single-buffer architecture was ∆ φ = 5.5° and the out-of-plane texture was ∆ ω = 3.4°. All the LZO films had very smooth surfaces, but LZO films grown on YSZ/CeO2 and CeO2/YSZ/CeO2 buffer architectures had cracks. The highly textured LZO film grown on CeO2-seed buffered NiW tape was suitable for the epitaxial growth of YBCO film with high currents.

  20. Raman study of CeO2 texture as a buffer layer in the CeO2/La2Zr2O7/Ni architecture for coated conductors.

    PubMed

    Jiménez, C; Caroff, T; Bartasyte, A; Margueron, S; Abrutis, A; Chaix-Pluchery, O; Weiss, F

    2009-04-01

    The CeO(2)/La(2)Zr(2)O(7)/Ni piled-up structure is a very promising architecture for YBa(2)Cu(3)O(7) (YBCO) coated conductors. We have grown YBCO/CeO(2)/LZO/Ni epitaxial structures by metalorganic decomposition (MOD) and metalorganic chemical vapor deposition (MOCVD) methods. The crystallographic quality of the CeO(2) layer is not well determined by conventional X-ray diffraction (XRD) due to the superposition of LZO and CeO(2) reflections. An alternative simple Raman spectroscopy analysis of the crystalline quality of the CeO(2) films is proposed. The F(2g) Raman mode of CeO(2) can be quantified either by using two polarization configurations (crossed or parallel) or at two different rotation angles around the normal axis (0 degrees and 45 degrees ) to obtain information about the sample texture. The sample texture can be determined via a quality factor (referred to as the Raman intensity ratio, RIR) consisting of calculating the ratio of the integrated intensity of the CeO(2) F(2g) mode at 0 degrees and 45 degrees in parallel polarization. This factor correlates with superconducting performance and the technique can be used as an on-line nondestructive characterization method.

  1. Vortex creep and critical current densities J c in a 2 μm thick SmBa2Cu3O7-d coated conductor with mixed pinning centers grown by co-evaporation

    NASA Astrophysics Data System (ADS)

    Haberkorn, N.; Coulter, Y.; Condó, A. M.; Granell, P.; Golmar, F.; Ha, H. S.; Moon, S. H.

    2016-07-01

    We report the critical current densities J c and flux creep rates in a 2 μm thick SmBa2Cu3O7-δ coated conductor produced by co-evaporation. The sample presents strong pinning produced by correlated disorder (CD) (boundaries between growth islands, dislocations and twin boundaries) as well as random nanoparticles. Correlated pinning along the c-axis was evidenced due to the appearance of a large peak in the angular critical current, centered at H║c. The analysis of the critical current density J c (with the magnetic field applied parallel (H║c) and at 45° of the c-axis (H║45°)) indicates that CD assists pinning throughout the temperature range. For all temperatures and at both angles the in-field dependence of J c exhibits a power-law behavior. The contribution of CD drops when the field is rotated to intermediate angles between the c axis and a-b axis (i. e. H║45°), which derives in a reduction of the absolute J c value and poorer in-field dependences. The flux creep rate depends on the angle and its values remain approximately constant within the power-law regime. For H║c and H║45° and for magnetic fields lower than 20 kOe, the flux relaxation presents characterizing glassy exponents μ = 1.70 and μ = 1.32, respectively.

  2. Fabrication and characterization of La2Zr2O7 films on different buffer architectures for YBa2Cu3O7−δ coated conductors by RF magnetron sputtering

    PubMed Central

    2013-01-01

    La2Zr2O7 (LZO) films were grown on different buffer architectures by radio frequency magnetron sputtering for the large-scale application of YBa2Cu3O7−x (YBCO)-coated conductors. The three different buffer architectures were cerium oxide (CeO2), yttria-stabilized zirconia (YSZ)/CeO2, and CeO2/YSZ/CeO2. The microstructure and surface morphology of the LZO film were studied by X-ray diffraction, optical microscopy, field emission scanning electron microscopy, and atomic force microscopy. The LZO films prepared on the CeO2, YSZ/CeO2, and CeO2/YSZ/CeO2 buffer architectures were preferentially c-axis-oriented and highly textured. The in-plane texture of LZO film on CeO2 single-buffer architecture was ∆ φ = 5.5° and the out-of-plane texture was ∆ ω = 3.4°. All the LZO films had very smooth surfaces, but LZO films grown on YSZ/CeO2 and CeO2/YSZ/CeO2 buffer architectures had cracks. The highly textured LZO film grown on CeO2-seed buffered NiW tape was suitable for the epitaxial growth of YBCO film with high currents. PMID:23445764

  3. Coatings.

    ERIC Educational Resources Information Center

    Anderson, Dennis G.

    1989-01-01

    This review covers analytical techniques applicable to the examination of coatings, raw materials, and substrates upon which coatings are placed. Techniques include chemical and electrochemical methods, chromatography, spectroscopy, thermal analysis, microscopy, and miscellaneous techniques. (MVL)

  4. Coatings.

    ERIC Educational Resources Information Center

    Anderson, Dennis G.

    1989-01-01

    This review covers analytical techniques applicable to the examination of coatings, raw materials, and substrates upon which coatings are placed. Techniques include chemical and electrochemical methods, chromatography, spectroscopy, thermal analysis, microscopy, and miscellaneous techniques. (MVL)

  5. Rapid doubling of the critical current of YBa2Cu3O7-δ coated conductors for viable high-speed industrial processing

    DOE PAGES

    Leroux, M.; Kihlstrom, K. J.; Holleis, S.; ...

    2015-11-09

    Here, we demonstrate that 3.5-MeV oxygen irradiation can markedly enhance the in-field critical current of commercial second generation superconducting tapes with an exposure time of just 1 s per 0.8 cm2. Furthermore we demonstrate how speed is now at the level required for an industrial reel-to-reel post-processing. The irradiation is made on production line samples through the protective silver coating and does not require any modification of the growth process. From TEM imaging, we identify small clusters as the main source of increased vortex pinning.

  6. SuperPower's Second Generation HTS Conductor Design for Stability and Low AC Losses

    NASA Astrophysics Data System (ADS)

    Hazelton, D. W.; Xie, Y. Y.; Qiao, Y.; Zhang, E.; Selvamanickam, V.

    2006-03-01

    SuperPower is developing a conductor design for improved mechanical properties, quench stability, and low ac losses. Coated conductors are typically 12 mm wide with a few microns of silver overlayer. SuperPower's design modifies such base conductor designs into geometries more suited for practical applications. Wide conductors are slit into 4 mm wide tapes, in particular for cable applications, but also to reduce ac losses. After slitting, the conductor is stabilized with approximately 20 microns of surround copper stabilizer, completely encapsulating the conductor and providing a hermetic seal. Other advantages of the surround copper stabilizer configuration are rounded edges for dielectric integration and superior over-current handling capability (9X critical current with 300 ms wide pulses). Prototype 1 m cables made by Sumitomo Electric using this practical conductor showed total ac losses under 0.4 W/kA-m. To further reduce ac losses, especially for high frequency applications of the military, SuperPower's conductor design involves striating the current-carrying layers by a photolithography process. Several racetrack coils made with our practical coated conductors have been provided to Rockwell Automation for use in a demonstration motor. Recent results of our practical coated conductor will be discussed.

  7. Plasma Generator Using Spiral Conductors

    NASA Technical Reports Server (NTRS)

    Szatkowski, George N. (Inventor); Dudley, Kenneth L. (Inventor); Ticatch, Larry A. (Inventor); Smith, Laura J. (Inventor); Koppen, Sandra V. (Inventor); Nguyen, Truong X. (Inventor); Ely, Jay J. (Inventor)

    2016-01-01

    A plasma generator includes a pair of identical spiraled electrical conductors separated by dielectric material. Both spiraled conductors have inductance and capacitance wherein, in the presence of a time-varying electromagnetic field, the spiraled conductors resonate to generate a harmonic electromagnetic field response. The spiraled conductors lie in parallel planes and partially overlap one another in a direction perpendicular to the parallel planes. The geometric centers of the spiraled conductors define endpoints of a line that is non-perpendicular with respect to the parallel planes. A voltage source coupled across the spiraled conductors applies a voltage sufficient to generate a plasma in at least a portion of the dielectric material.

  8. Anchored terminal conductor

    SciTech Connect

    Milewski, M.A.; Delmolino, W.P.

    1986-08-19

    An electrochemical cell is described comprising a cell container which is closed by a resilient insulative cell top and an electrode conductor inserted through the cell top and into an electrode of the cell, with the electrode conductor being physically and electrically accessible to the exterior of the cell whereby it functions as a terminal for the electrode, and wherein a portion of the electrode conductor is enclosed within the cell top, characterized in that the cell further comprises means for substantially restraining movement of the electrode conductor relative to the cell top. The electrode conductor has a nail configuration comprising a head and a shank with the head of the nail providing the external physical and electrical accessibility, wherein the restraining means is integrated with the shank of the nail. The restraining means is positioned on the shank, interior to the cell container and below the interior surface of the cell top and in close juxtaposition to the interior surface. The restraining means comprises a circumferential barb longitudinally disposed on the shank and having an upper portion which engages the interior surface to provide the substantial restraining of movement.

  9. Depth profiling of the microwave surface resistance of high-J C GdBa2Cu3O7-δ coated conductors grown using the RCE-DR process

    NASA Astrophysics Data System (ADS)

    Yang, Woo, II; Jung, Ho Sang; Lee, Jae-Hun; Lee, Hunju; Moon, Seung-Hyun; Lee, Jung-Woo; Yoo, Sang-Im; Lee, Sang Young

    2016-10-01

    We study depth profiling of the microwave surface resistance (R S) of GdBa2Cu3O7-δ (GdBCO) coated conductors (CCs) grown using the reactive co-evaporation by deposition and reaction (RCE-DR) method, a method enabling extremely high deposition rate. GdBCO CCs with the critical current (I C) of more than 790 A cm-1 at 77 K in self-field are used for the study. The R S of the GdBCO CCs is measured at temperatures of 10-80 K using a 8.5 GHz TE011-mode rutile resonator, which is compared with that of YBa2Cu3O7-δ films and GdBCO films epitaxially grown on single crystal substrates. It turns out that there is significant inhomogeneity in the R S over the thickness of the GdBCO layer, with the R S value of the top part at 30 K being almost two times higher than the corresponding one of the bottom part. A transmission electron microscopy study reveals that Gd2O3 grains coexist with GdBCO grains with the average Gd2O3 grain sizes being ˜150 nm at the top and ˜100 nm at the bottom of the GdBCO layer. We relate the inhomogeneity in the R S of the GdBCO layer with the positional dependence of the Gd2O3 grain size, for which effects of the dielectric losses from the Gd2O3 grains on the measured R S of the GdBCO layer are considered. Our results imply that the critical current density, another important transport property of superconductors, could be inhomogeneous over the thickness of the GdBCO layer grown using the RCE-DR method.

  10. Experimental measurement of characteristic I(c) (ε, θ, B) response in GdBa2Cu3Oδ coated conductor tapes under low magnetic field at 77 K.

    PubMed

    Shin, Hyung-Seop; Dedicatoria, Marlon J; Gorospe, Alking; Lee, Sang-Heon

    2015-03-01

    The continued development in the design technology of practical superconducting devices adopting high temperature superconductors tapes has led to a deeper understanding of their electromechanical behaviors. Rare-earth-barium-copper-oxide coated conductor (CC) tapes exhibit anisotropy of transport property (Ic) under magnetic field and its intrinsic strain effect is much significant depending on the orientation to the tape surface and the magnetic field intensity applied. Different experimental systems have already been developed to measure the relation of Ic with mechanical strain ε, magnetic field intensity B, and its angle of orientation, θ. However, few systems and instruments can measure these relationships simultaneously; either Ic-B-θ or Ic-ε-B is usually measured. In this study, a device which can measure these influences simultaneously based on a pair of permanent magnet systems was constructed and the characteristic responses of critical current Ic with strain, magnetic field, and its orientation with respect to the CC tape surface were investigated. The angular dependence of Ic with strain at 77 K in reactive co-evaporation by deposition and reaction GdBCO CC tapes has been measured using the permanent magnet system. The orientation angle of magnetic field with respect to the tape's surface was varied by rotating the rig fixture that holds a pair of permanent magnets. The strain sensitivity of Ic at different angles under low magnetic field was evaluated. As a result, a characteristic surface Ic (ε, θ, B) has been constructed as the characteristic response of Ic with strain and varying orientation under magnetic field.

  11. Decoupling and tuning competing effects of different types of defects on flux creep in irradiated YBa2Cu3O7-δ coated conductors

    SciTech Connect

    Eley, S.; Leroux, M.; Rupich, M. W.; Miller, D. J.; Sheng, H.; Niraula, P. M.; Kayani, A.; Welp, U.; Kwok, W. -K.; Civale, L.

    2016-11-15

    YBa2Cu3O7-δ coated conductors (CCs) have achieved high critical current densities (J c) that can be further increased through the introduction of additional defects using particle irradiation. However, these gains are accompanied by increases in the flux creep rate, a manifestation of competition between the different types of defects. Here, we study this competition to better understand how to design pinning landscapes that simultaneously increase J c and reduce creep. CCs grown by metal organic deposition show non-monotonic changes in the temperature-dependent creep rate, S(T). Notably, in low fields, there is a conspicuous dip to low S as the temperature (T) increases from ~20 to ~65 K. Oxygen-, proton-, and Au-irradiation substantially increase S in this temperature range. Focusing on an oxygen-irradiated CC, we investigate the contribution of different types of irradiation-induced defects to the flux creep rate. Specifically, we study S(T) as we tune the relative density of point defects to larger defects by annealing both an as-grown and an irradiated CC in O2 at temperatures T A = 250 °C–600 °C. We observe a steady decrease in S(T > 20 K) with increasing T A, unveiling the role of pre-existing nanoparticle precipitates in creating the dip in S(T) and point defects and clusters in increasing S at intermediate temperatures.

  12. Strong flux pinning at 4.2 K in SmBa2Cu3O y coated conductors with BaHfO3 nanorods controlled by low growth temperature

    NASA Astrophysics Data System (ADS)

    Miura, S.; Tsuchiya, Y.; Yoshida, Y.; Ichino, Y.; Awaji, S.; Matsumoto, K.; Ibi, A.; Izumi, T.

    2017-08-01

    In order to apply REBa2Cu3O y (REBCO, RE = rare earth elements or Y) coated conductors in high magnetic field, coil-based applications, the isotropic improvement of their critical current performance with respect to the directions of the magnetic field under these operating conditions is required. Most applications operate at temperatures lower than 50 K and magnetic fields over 2 T. In this study, the improvement of critical current density (J c) performance for various applied magnetic field directions was achieved by controlling the nanostructure of the BaHfO3 (BHO)-doped SmBa2Cu3O y (SmBCO) films on metallic substrates. The corresponding minimum J c value of the films at 40 K under an applied 3 T field was 5.2 MA cm-2, which is over ten times higher than that of a fully optimized Nb-Ti wire at 4.2 K. At 4.2 K, under a 17.5 T field, a flux pinning force density of 1.4 TN m-3 for B//c was realized; this value is among the highest values reported for REBCO films to date. More importantly, the F p for B//c corresponds to the minimum value for various applied magnetic field directions. We investigated the dominant flux pinning centers of films at 4.2 K using the anisotropic scaling approach based on the effective mass model. The dominant flux pinning centers are random pinning centers at 4.2 K, i.e., a high pinning performance was achieved by the high number density of random pins in the matrix of the BHO-doped SmBCO films.

  13. Tensile fatigue behavior and crack growth in GdBa2Cu3O7‑x /stainless-steel coated conductor grown via reactive co-evaporation

    NASA Astrophysics Data System (ADS)

    Rogers, Samuel; Schwartz, Justin

    2017-04-01

    (RE)Ba2Cu3O7‑x (REBCO) conductors have the potential to enable a wide range of superconducting applications over a range of temperatures and magnetic fields (Vincent et al 2013 IEEE Trans. Appl. Supercond. 23 5700805), yet AC applications and devices with a charge/discharge cycle may be limited by the conductor fatigue properties. Here the fatigue behavior of GdBa2Cu3O7‑x (GdBCO) conductors grown by reactive co-evaporation on stainless-steel substrates is reported for axial tensile strains, ε, up to 0.5% and 100 000 cycles. Failure mechanisms are investigated via microstructural studies and compared with a commercially available IBAD/MOCVD REBCO conductor. Results show that GdBCO/stainless-steel conductors retain their transport critical current for 10 000 cycles at ε = 0.35% and ε = 0.45%, and for 1000 cycles at ε = 0.50%. The main cause of fatigue degradation in GdBCO conductors is crack propagation and delamination that initiates at the edge of the conductor due to manufacturing defects.

  14. Plasmonic transparent conductors

    NASA Astrophysics Data System (ADS)

    Liapis, Andreas C.; Sfeir, Matthew Y.; Black, Charles T.

    2016-09-01

    Many of today's technological applications, such as solar cells, light-emitting diodes, displays, and touch screens, require materials that are simultaneously optically transparent and electrically conducting. Here we explore transparent conductors based on the excitation of surface plasmons in nanostructured metal films. We measure both the optical and electrical properties of films perforated with nanometer-scale features and optimize the design parameters in order to maximize optical transmission without sacrificing electrical conductivity. We demonstrate that plasmonic transparent conductors can out-perform indium tin oxide in terms of both their transparency and their conductivity.

  15. Transport Jc Measurements of HTS Conductors under High Magnetic Field at LNCMI

    NASA Astrophysics Data System (ADS)

    Chaud, Xavier; Debray, François; Mossang, Eric; Tixador, Pascal; Rey, Jean-Michel; Lecrevisse, Thibault; Bruzek, Christian-Eric

    The LNCMI, the national French high magnetic field facility, provides high fields generated mainly by resistive magnets. Because of the forecast increasing price of electricity, LNCMI has a strong incentive to participate to the development and characterizations of HTS conductors in view of their use for the generation of strong field. Latest YBCO coated conductors have improved properties showing a great potential with that respect, without excluding Bi2212 and MgB2 for particular cases. We present the existing set-up to measure short straight or VAMAS type coil samples at variable temperature and high field up to 30 T, and some measurements obtained on different HTS conductors, Bi2212 round wires and YBCO coated conductors. We also report on the first results obtained at 18 T with a pancake coil made of commercial YBCO coated conductor tapes on a newly developed solenoid test bench.

  16. Theory of Superionic Conductors

    DTIC Science & Technology

    1981-09-01

    TYPE OF REPORT 6 PERIOO COVERED Final Technical )THEORY OF SUPERIONIC CONDUCTORS 9/30/76 to 9/30/81 SVIERFORMI- 4G ORG REPURT NUMBER AI I 1,701 ,- S...several mathematical models of ion and electron conduction in many-particle systems. . DD AN 1473 SECURIT "-CLASSIiCAt N OF THIS PAGE 1 (Wen D E / / A

  17. In situ drop-coated BaZr 0.1Ce 0.7Y 0.2O 3- δ electrolyte-based proton-conductor solid oxide fuel cells with a novel layered PrBaCuFeO 5+ δ cathode

    NASA Astrophysics Data System (ADS)

    Zhao, Ling; He, Beibei; Nian, Qiong; Xun, Zhiqing; Peng, Ranran; Meng, Guangyao; Liu, Xingqin

    In order to develop a simple and cost-effective route to fabricate proton-conductor intermediate-temperature SOFCs, a dense BaZr 0.1Ce 0.7Y 0.2O 3- δ (BZCY) electrolyte was fabricated on a porous anode by in situ drop-coating. The PrBaCuFeO 5+ δ (PBCF) composite oxide with layered perovskite structure was synthesized by auto ignition process and examined as a novel cathode for proton-conductor IT-SOFCs. The single cell, consisting of PBCF/BZCY/NiO-BZCY structure, was assembled and tested from 600 to 700 °C with humidified hydrogen (˜3% H 2O) as the fuel and the static air as the oxidant. An open-circuit potential of 1.01 V and a maximum power density of 445 mW cm -2 at 700 °C were obtained for the single cell. A relatively low interfacial polarization resistance of 0.15 Ω cm 2 at 700 °C indicated that the PBCF is a promising cathode for proton-conductor IT-SOFCs.

  18. Polymeric ion conductors

    SciTech Connect

    Nagai, J.; Mizuhashi, M.; Kamimori, T.

    1990-12-31

    There are several requirements for (polymeric) ion conductors in electrochromic window applications: (1) they have high ionic conductivity (desirably, > 1 {times} 10{sup {minus}4} Scm{sup {minus}1}); (2) they have high chemical and electrochemical stabilities with respect to the wide usable potential window and thermal and UV stabilities; (3) they are transparent in a specific wavelength region, which is, however, dependent of applications; and (4) they have enough adhesiveness to the substrates and have acceptable mechanical properties. Many kinds of polymeric ionic conductors have since been reported and some of them were applied to electrochromic uses. In this chapter, electrochemical and physicochemical properties of these materials are reviewed. However, certain aspects such as crystallographic studies and conduction models in detail have been omitted, which are still controversial.

  19. Plasmonic Graphene Transparent Conductors

    DTIC Science & Technology

    2012-01-01

    www.MaterialsViews.com www.advopticalmat.de FU LL P A P ER Guowei Xu,* Jianwei Liu, Qian Wang , Rongqing Hui, Zhijun Chen, Victor A. Maroni, and Judy Wu Plasmonic...decision, unless so designated by other documentation. 12. DISTRIBUTION AVAILIBILITY STATEMENT Approved for public release; distribution is unlimited. UU...Box 12211 Research Triangle Park, NC 27709-2211 15. SUBJECT TERMS surface plasmon, graphene, transparent conductors Guowei Xu, Jianwei Liu, Qian

  20. Intercalated Graphite Fiber Conductor.

    DTIC Science & Technology

    1980-12-01

    Lightweight electrical conductors were developed from graphitic fibers inter- calated with highly electrophilic intercalants. Conductance increases of...intercalated with highly electrophilic molecules ("intercalants") to en- hance their electrical conductivity. Evaluation of the elec- trical resistance of two...corrosion resistant to fluorine containing chemicals. Since the moisture permeability of the TFE is much less than that of the FEP, attempts were made to

  1. Fast Ion Conductors

    NASA Astrophysics Data System (ADS)

    Chadwick, Alan V.

    Fast ion conductors, sometimes referred to as superionic conductors or solid electrolytes, are solids with ionic conductivities that are comparable to those found in molten salts and aqueous solutions of strong electrolytes, i.e., 10-2-10 S cm-1. Such materials have been known of for a very long time and some typical examples of the conductivity are shown in Fig. 1, along with sodium chloride as the archetypal normal ionic solid. Faraday [1] first noted the high conductivity of solid lead fluoride (PbF2) and silver sulphide (Ag2S) in the 1830s and silver iodide was known to be unusually high ionic conductor to the German physicists early in the 1900s. However, the materials were regarded as anomalous until the mid 1960s when they became the focus of intense interest to academics and technologists and they have remained at the forefront of materials research [2-4]. The academic aim is to understand the fundamental origin of fast ion behaviour and the technological goal is to utilize the properties in applications, particularly in energy applications such as the electrolyte membranes in solid-state batteries and fuel cells, and in electrochemical sensors. The last four decades has seen an expansion of the types of material that exhibit fast ion behaviour that now extends beyond simple binary ionic crystals to complex solids and even polymeric materials. Over this same period computer simulations of solids has also developed (in fact these methods and the interest in fast ion conductors were almost coincidental in their time of origin) and the techniques have played a key role in this area of research.

  2. Coupling of the orthorhombic distortion to the depression of the {Tc}`s due to Zn{sup 2+} doping in the ``RE-123`` HTSC`s: A (d + s)-wave picture

    SciTech Connect

    Tang, I.M.; Thongruang, R.; Charoenthai, N.

    1999-07-10

    The depressions of the {Tc}`s of the 123 REBa{sub 2}Cu{sub 3}O{sub 7} HTSC`s due to the substitution of Zn{sup 2+} ions into the Cu(2) layer are studied. The orthorhombic distortion which occurs in the 123 ceramics is assumed to induce a modification to the spin-fluctuation (SF) mediated pairing interaction which in turn causes the order parameters of these HTSC`s to be of mixed (d + s)-wave symmetry. It is shown that part of the rapid depression of the {Tc}`s caused by Zn{sup 2+} substitution into the CuO{sup 2} is due to a reduction of the SF-mediated pairing interaction. The differences in the rates of suppression of {Tc} due to Zn{sup 2+} doping in the different RE-123 HTSC`s are shown to be due to the changes in the orthorhombicity which depend on the size of the rare earth ions.

  3. Transparent electronic conductors in electrochromic devices

    SciTech Connect

    Misonou, M.; Kawahara, H.

    1990-12-31

    Materials with both high transparency and high electrical conductance have recently attracted growing technological interest. Applications of such materials include coatings for windows with ability of deicing and demisting, coatings, for electromagnetic shielding and antistatic coatings. Today, their application has been extended toward optoelectronic devices. They are being used for the fabrication of a variety of devices such as photovoltaic devices, display devices and light control devices which include electrochromic devices. Here, transparent electronic conductors are discussed with regard to their properties required by electrochromic devices at first. Since an electrochromic device is a so called current-driven device, it requires substantially low electrical resistance. In fact, the performance of transparent electrodes is one of the key factors to limit the performance of the electrochromic devices today. Next, materials having a potential to satisfy the device requirements are reviewed. Candidates are thin metals and heavily doped semiconductors with wide band gap. Among them wide gap semiconductors, especially metal oxides, are more relevant than metals with respect to chemical durability and electrical and optical performances. Coating technologies for large area transparent electrodes are presented for two special cases; one is chemical vapor deposition (CVD) technology for tin oxide coating and the other is sputtering technology for indium tin oxide(ITO) coating. Both are widely recognized as materials showing superior performance, and in fact they are commonly used for the above mentioned applications.

  4. YBCO Coated Conductors with Reduced AC Losses

    DTIC Science & Technology

    2008-01-30

    discussed before, substrates made using PM Ni-5W, with 150-250 ppm C, often resulted in a retained roll texture and a 100% cube texture did not develop...transition above Ni-5W: the texture at 7 and 9 at% W is no longer a pure cube texture but shows an increasing presence of the brass texture. Both PM- and...ingot Ni-9.3W- based substrates showed a 50% cube texture , insufficient for 2G HTS manufacture. This high W compositional range was therefore

  5. Dip-coated multi-core (Bi,Pb) 2Sr 2Ca 2Cu 3O x tape process - an alternative way of fabricating multi-core (Bi,Pb) 2Sr 2Ca 2Cu 3O x tape conductors

    NASA Astrophysics Data System (ADS)

    Sung, Y. S.; Kumakura, H.; Togano, K.

    2000-04-01

    The dip-coating-then-stacking (DIS) process, which is simpler and easier than the oxide-powder-in-tube (OPIT) process, was developed to fabricate multi-core (Bi,Pb) 2Sr 2Ca 2Cu 3O x conductors. In the DIS process, multi-core tapes were prepared by stacking several layers of single side dip-coated Ag strips then wrapping them with Ag foil. After burning at 500°C to remove organic materials, tape samples were rolled to increase the packing density of oxide core, then were heat-treated twice at 838°C in air with an intermediate pressing. There was no bubbling problem throughout the heat treatment and the interface between oxide core and Ag was very smooth. By the DIS process, transport critical current ( Ic) ∼73 A and transport critical current density ( Jc) ∼17 600 A/cm 2 at 77 K, 0 T were so far obtained. Considering the easiness and simplicity of the DIS process relative to OPIT with reasonably high Ic and Jc values so far obtained, it appears that the DIS process can be applied as an alternative way to OPIT for fabricating multi-core (Bi,Pb) 2Sr 2Ca 2Cu 3O x tape conductors.

  6. The Influence of Music Style and Conductor Race on Perceptions of Ensemble and Conductor Performance

    ERIC Educational Resources Information Center

    Vanweelden, Kimberly; McGee, Isaiah R.

    2007-01-01

    The purpose of this study was to examine music style and conductor race on perceptions of ensemble and conductor performance. Results found that conductor race and music style significantly affected ratings of ensemble and conductor performance. Evaluators rated a white conductor group higher than a black conductor group conducting the same…

  7. Improvement of SOFC electrodes using mixed ionic-electronic conductors

    SciTech Connect

    Matsuzaki, Y.; Hishinuma, M.

    1996-12-31

    Since the electrode reaction of SOFC is limited to the proximity of a triple phase boundary (TPB), the local current density at the electrode and electrolyte interface is larger than mean current density, which causes large ohmic and electrode polarization. This paper describes an application of mixed ionic-electronic conductors to reduce such polarization by means of (1) enhancing ionic conductivity of the electrolyte surface layer by coating a high ionic conductors, and (2) reducing the local current density by increasing the electrochemically active sites.

  8. Photoluminescent conductor polymer holograms

    NASA Astrophysics Data System (ADS)

    Ruiz-Limón, B.; Olivares-Pérez, A.; Ponce-Lee, E. L.; Hernández-Garay, M. P.; Páez-Trujillo, G.; Fuentes-Tapia, I.

    2007-02-01

    An organic conductor polymer was doped with benzalkonium chloride to get a photoluminescent effect at 560 nm and it was used as holographic material. We used a digital image to generate a hologram in a computer and it was transferred by microlithography techniques to our polymer to get a phase hologram. The transference is successful by rubbing, the heat increment produce temperature gradients and the information in the mask is transferred to the material by the refraction index changes, thus the film is recorded. We recorded some gratings to observe the behavior of photoluminescent light with different frequencies when it is radiated with a green laser beam at 532 nm.

  9. Floating insulated conductors for heating subsurface formations

    DOEpatents

    Burns, David; Goodwin, Charles R.

    2014-07-29

    A heating system for a subsurface formation includes a conduit located in a first opening in the subsurface formation. Three electrical conductors are located in the conduit. A return conductor is located inside the conduit. The return conductor is electrically coupled to the ends of the electrical conductors distal from the surface of the formation. Insulation is located inside the conduit. The insulation electrically insulates the three electrical conductors, the return conductor, and the conduit from each other.

  10. 76 FR 69801 - Conductor Certification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-09

    ... meet minimum Federal safety standards serve as conductors, to reduce the rate and number of accidents... shall require that train conductors be trained, in accordance with the training standards developed... often favorably inclined toward the RSAC recommendation. However, FRA is in no way bound to follow...

  11. Fluorite Ce0.8Sm0.2O2- δ porous layer coating to enhance the oxygen permeation behavior of a BaCo0.7Fe0.2Nb0.1O3- δ mixed conductor

    NASA Astrophysics Data System (ADS)

    Wang, Tai-he; Song, Wei-jia; Li, Rong; Zhen, Qiang

    2016-06-01

    Fluorite Ce0.8Sm0.2O2- δ (SDC) nanopowder with a crystallite size of 15 nm was synthesized by a co-precipitation method. An SDC porous layer was coated onto a BaCo0.7Fe0.2Nb0.1O3- δ (BCFN) mixed conductor to improve its oxygen transport behavior. The results show that the SDC-coated BCFN membrane exhibits a remarkably higher oxygen permeation flux ({J_{{O_2}}}) than the uncoated BCFN in the partial oxidation of coke oven gas (COG). The maximum {J_{{O_2}}} value of the SDC-coated BCFN is 18.28 mL·min-1·cm-2 under a COG/air flux of 177 mL·min-1/353 mL·min-1 at 875°C when the thickness of the BCFN membrane is 1 mm; this {J_{{O_2}}} value is 23% higher than that of the uncoated BCFN membrane. This enhancement is likely because of the higher oxygen ionic conductivity of SDC, which supplies oxygen vacancies and accelerates oxygen exchange on the membrane/coating layer/gas three-phase boundary.

  12. 35.4 T field generated using a layer-wound superconducting coil made of (RE)Ba2Cu3O7-x (RE = rare earth) coated conductor

    NASA Astrophysics Data System (ADS)

    Trociewitz, Ulf P.; Dalban-Canassy, Matthieu; Hannion, Muriel; Hilton, David K.; Jaroszynski, Jan; Noyes, Patrick; Viouchkov, Youri; Weijers, Hubertus W.; Larbalestier, David C.

    2011-11-01

    To explore the limits of layer wound (RE)Ba2Cu3O7-x (REBCO, RE = rare earth) coils in a high magnetic field environment >30 T, a series of small insert coils have been built and characterized in background fields. One of the coils repeatedly reached 35.4 T using a single ˜100 m length of REBCO tape wet wound with epoxy and nested in a 31 T background magnet. The coil was quenched safely several times without degradation. Contributing to the success of this coil was the introduction of a thin polyester film that surrounded the conductor. This approach introduces a weak circumferential plane in the coil pack that prevents conductor delamination that has caused degradation of several epoxy impregnated coils previously made by this and other groups.

  13. Intercalated graphite electrical conductors

    NASA Technical Reports Server (NTRS)

    Banks, B. A.

    1983-01-01

    For years NASA has wanted to reduce the weight of spacecraft and aircraft. Experiments are conducted to find a lightweight synthetic metal to replace copper. The subject of this paper, intercalated graphite, is such a material. Intercalated graphite is made by heating petroleum or coal to remove the hydrogen and to form more covalent bonds, thus increasing the molecular weight. The coal or petroleum eventually turns to pitch, which can then be drawn into a fiber. With continued heating the pitch-based fiber releases hydrogen and forms a carbon fiber. The carbon fiber, if heated sufficiently, becomes more organized in parallel layers of hexagonally arranged carbon atoms in the form of graphite. A conductor of intercalated graphite is potentially useful for spacecraft or aircraft applications because of its low weight.

  14. Plasmonic graphene transparent conductors.

    PubMed

    Xu, Guowei; Liu, Jianwei; Wang, Qian; Hui, Rongqing; Chen, Zhijun; Maroni, Victor A; Wu, Judy

    2012-03-08

    Plasmonic graphene is fabricated using thermally assisted self-assembly of silver nanoparticles on graphene. The localized surface-plasmonic effect is demonstrated with the resonance frequency shifting from 446 to 495 nm when the lateral dimension of the Ag nanoparticles increases from about 50 to 150 nm. Finite-difference time-domain simulations are employed to confirm the experimentally observed light-scattering enhancement in the solar spectrum in plasmonic graphene and the decrease of both the plasmonic resonance frequency and amplitude with increasing graphene thickness. In addition, plasmonic graphene shows much-improved electrical conductance by a factor of 2-4 as compared to the original graphene, making the plasmonic graphene a promising advanced transparent conductor with enhanced light scattering for thin-film optoelectronic devices.

  15. Transmission lines with very lossy conductors and seawater return

    NASA Astrophysics Data System (ADS)

    Martin, G. E.

    1982-10-01

    There are potential benefits in undersea cable technology by the use of copper-coated non-conductors (Kevlar) or poor conductors (graphite) with conventional or sea-water outer conductor. Kevlar is a very strong non-conductive fiber even in small sizes and it can be fabricated as a bundle of many copper-coated strands. Non-metallic conductors are being developed for a wide range of uses. For example, graphite materials are being used to provide strong flexible golf clubs and spark plug wires that cause minimal interference with radio reception. There is extensive research and development in these materials such as development of light-weight strong materials for airplanes. The particular application of interest in the research reported here is the cables used as undersea data links for transmitting signals from hydrophones under water to sonobuoy radio transmitters at the surface of the ocean. Non-metallic conducting materials have recently shown impressive capabilities and prospective future gains from the viewpoint of such ocean applications including high strength, low specific gravity and relatively low resistance. This report is intended to provide the technical development of such data transmission lines in order to provide the basis for design of such cables. The technical basis for the design of undersea cables is provided in considerable detail. The electromagnetic theory, algorithm development, and properties of materials are described. Optimal designs are considered.

  16. Flat conductor cable commercialization project

    NASA Technical Reports Server (NTRS)

    Hogarth, P.; Wadsworth, E.

    1977-01-01

    An undercarpet flat conductor cable and a baseboard flat conductor cable system were studied for commercialization. The undercarpet system is designed for use in office and commercial buildings. It employs a flat power cable, protected by a grounded metal shield, that terminates in receptacles mounted on the floor. It is designed to interface with a flat conductor cable telephone system. The baseboard system consists of a flat power cable mounted in a plastic raceway; both the raceway and the receptacles are mounted on the surface of the baseboard. It is designed primarily for use in residential buildings, particularly for renovation and concrete and masonry construction.

  17. 30 CFR 57.12004 - Electrical conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electrical conductors. 57.12004 Section 57... Surface and Underground § 57.12004 Electrical conductors. Electrical conductors shall be of a sufficient... operations will not damage the insulating materials. Electrical conductors exposed to mechanical damage shall...

  18. 30 CFR 57.12004 - Electrical conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electrical conductors. 57.12004 Section 57... Surface and Underground § 57.12004 Electrical conductors. Electrical conductors shall be of a sufficient... operations will not damage the insulating materials. Electrical conductors exposed to mechanical damage shall...

  19. 30 CFR 56.12004 - Electrical conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electrical conductors. 56.12004 Section 56....12004 Electrical conductors. Electrical conductors shall be of a sufficient size and current-carrying... insulating materials. Electrical conductors exposed to mechanical damage shall be protected. ...

  20. 30 CFR 56.12004 - Electrical conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electrical conductors. 56.12004 Section 56....12004 Electrical conductors. Electrical conductors shall be of a sufficient size and current-carrying... insulating materials. Electrical conductors exposed to mechanical damage shall be protected. ...

  1. 33 CFR 183.445 - Conductors: Protection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Conductors: Protection. 183.445 Section 183.445 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... Conductors: Protection. (a) Each conductor or group of conductors that passes through a bulkhead,...

  2. 30 CFR 57.12004 - Electrical conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electrical conductors. 57.12004 Section 57... Surface and Underground § 57.12004 Electrical conductors. Electrical conductors shall be of a sufficient... operations will not damage the insulating materials. Electrical conductors exposed to mechanical damage...

  3. Conductor for a fluid-cooled winding

    DOEpatents

    Kenney, Walter J.

    1983-01-01

    A conductor and method of making the conductor are provided for use in winding electrical coils which are cooled by a fluid communicating with the conductor. The conductor is cold worked through twisting and reshaping steps to form a generally rectangular cross section conductor having a plurality of helical cooling grooves extending axially of the conductor. The conductor configuration makes it suitable for a wide variety of winding applications and permits the use of simple strip insulation between turns and perforated sheet insulation between layers of the winding.

  4. Testing flat-conductor cable

    NASA Technical Reports Server (NTRS)

    Loggins, R. W.; Herndon, R. H.

    1976-01-01

    Report describes characteristics of type of FCC which consists of three AWG No. 12 flat copper conductors laminated between two films of polyethylene terephthalate (Mylar) insulation with self-extinguishing polyester adhesive.

  5. Special Report: Solid Ionic Conductors.

    ERIC Educational Resources Information Center

    Shriver, Duward F.; Farrington, Gregory C.

    1985-01-01

    Solid ionic conductors are unusual materials that may find valuable applications in devices ranging from high-energy density batteries to lasers. The nature of these materials and their potential uses are discussed. (JN)

  6. 77 FR 6482 - Conductor Certification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-08

    ... management'' (CRM), a concept perfected in aviation and urgently pressed on the railroad industry by the... railroads have included CRM in their training programs. It is particularly important that a conductor...

  7. High Temperature Protonic Conductors

    NASA Technical Reports Server (NTRS)

    Dynys, Fred; Berger, Marie-Helen; Sayir, Ali

    2007-01-01

    High Temperature Protonic Conductors (HTPC) with the perovskite structure are envisioned for electrochemical membrane applications such as H2 separation, H2 sensors and fuel cells. Successive membrane commercialization is dependent upon addressing issues with H2 permeation rate and environmental stability with CO2 and H2O. HTPC membranes are conventionally fabricated by solid-state sintering. Grain boundaries and the presence of intergranular second phases reduce the proton mobility by orders of magnitude than the bulk crystalline grain. To enhanced protonic mobility, alternative processing routes were evaluated. A laser melt modulation (LMM) process was utilized to fabricate bulk samples, while pulsed laser deposition (PLD) was utilized to fabricate thin film membranes . Sr3Ca(1+x)Nb(2-x)O9 and SrCe(1-x)Y(x)O3 bulk samples were fabricated by LMM. Thin film BaCe(0.85)Y(0.15)O3 membranes were fabricated by PLD on porous substrates. Electron microscopy with chemical mapping was done to characterize the resultant microstructures. High temperature protonic conduction was measured by impedance spectroscopy in wet air or H2 environments. The results demonstrate the advantage of thin film membranes to thick membranes but also reveal the negative impact of defects or nanoscale domains on protonic conductivity.

  8. A lithium superionic conductor.

    PubMed

    Kamaya, Noriaki; Homma, Kenji; Yamakawa, Yuichiro; Hirayama, Masaaki; Kanno, Ryoji; Yonemura, Masao; Kamiyama, Takashi; Kato, Yuki; Hama, Shigenori; Kawamoto, Koji; Mitsui, Akio

    2011-07-31

    Batteries are a key technology in modern society. They are used to power electric and hybrid electric vehicles and to store wind and solar energy in smart grids. Electrochemical devices with high energy and power densities can currently be powered only by batteries with organic liquid electrolytes. However, such batteries require relatively stringent safety precautions, making large-scale systems very complicated and expensive. The application of solid electrolytes is currently limited because they attain practically useful conductivities (10(-2) S cm(-1)) only at 50-80 °C, which is one order of magnitude lower than those of organic liquid electrolytes. Here, we report a lithium superionic conductor, Li(10)GeP(2)S(12) that has a new three-dimensional framework structure. It exhibits an extremely high lithium ionic conductivity of 12 mS cm(-1) at room temperature. This represents the highest conductivity achieved in a solid electrolyte, exceeding even those of liquid organic electrolytes. This new solid-state battery electrolyte has many advantages in terms of device fabrication (facile shaping, patterning and integration), stability (non-volatile), safety (non-explosive) and excellent electrochemical properties (high conductivity and wide potential window).

  9. A lithium superionic conductor

    NASA Astrophysics Data System (ADS)

    Kamaya, Noriaki; Homma, Kenji; Yamakawa, Yuichiro; Hirayama, Masaaki; Kanno, Ryoji; Yonemura, Masao; Kamiyama, Takashi; Kato, Yuki; Hama, Shigenori; Kawamoto, Koji; Mitsui, Akio

    2011-09-01

    Batteries are a key technology in modern society. They are used to power electric and hybrid electric vehicles and to store wind and solar energy in smart grids. Electrochemical devices with high energy and power densities can currently be powered only by batteries with organic liquid electrolytes. However, such batteries require relatively stringent safety precautions, making large-scale systems very complicated and expensive. The application of solid electrolytes is currently limited because they attain practically useful conductivities (10-2 S cm-1) only at 50-80 °C, which is one order of magnitude lower than those of organic liquid electrolytes. Here, we report a lithium superionic conductor, Li10GeP2S12 that has a new three-dimensional framework structure. It exhibits an extremely high lithium ionic conductivity of 12 mS cm-1 at room temperature. This represents the highest conductivity achieved in a solid electrolyte, exceeding even those of liquid organic electrolytes. This new solid-state battery electrolyte has many advantages in terms of device fabrication (facile shaping, patterning and integration), stability (non-volatile), safety (non-explosive) and excellent electrochemical properties (high conductivity and wide potential window).

  10. Coating method enables low-temperature brazing of stainless steel

    NASA Technical Reports Server (NTRS)

    Seaman, F. D.

    1965-01-01

    Gold coated stainless steel tubes containing insulated electrical conductors are brazed at a low temperature to a copper coated stainless steel sealing block with a gold-copper eutectic. This produces an effective seal without using flux or damaging the electrical conductors.

  11. Marine conductor coupling

    SciTech Connect

    Regan, A.M.

    1985-01-01

    A marine conductor coupling is shown in use in a subsea well installation for connecting a blowout preventer stack to the subsea well head with the coupling including a one piece body of annular configuration having a mandrel receiving vertical bore aligned to a vertical through bore, a plurality of latching dogs received in a mating plurality of horizontally disposed dog receiving slots extending through the annular side wall of the body normal to and intersecting the mandrel receiving bore, mounting studs for connecting the body directly to the associated blowout preventer stack component, whereby forces tending to separate the connector body from the well head mandrel are transmitted directly through the one piece body of the connector, an actuating ring disposed about the inclined rear faces of the latching dogs for urging the dogs into latching engagement with the mandrel, a knock-out ring having a lost motion connection to and being suspended below the actuating ring to be raised by dog releasing motion of the actuating ring to knock the dogs out of their latching engagement with the mandrel and a plurality of hydraulic piston and cylinder means wherein the pistons and piston rods are fixed in stationary relationship to the connector body and associated hydraulic cylinders move vertically relative thereto under hydraulic pressuring and are connected directly to the actuator ring to move it selectively between latching dog wedging and release positions with an indicator rod protruding through a housing surrounding the actuator ring to indicate visually exteriorly of the housing the position of the actuating ring interiorly of the housing.

  12. Zinc oxyfluoride transparent conductor

    DOEpatents

    Gordon, Roy G.

    1991-02-05

    Transparent, electrically conductive and infrared-reflective films of zinc oxyfluoride are produced by chemical vapor deposition from vapor mixtures of zinc, oxygen and fluorine-containing compounds. The substitution of fluorine for some of the oxygen in zinc oxide results in dramatic increases in the electrical conductivity. For example, diethyl zinc, ethyl alcohol and hexafluoropropene vapors are reacted over a glass surface at 400.degree. C. to form a visibly transparent, electrically conductive, infrared reflective and ultraviolet absorptive film of zinc oxyfluoride. Such films are useful in liquid crystal display devices, solar cells, electrochromic absorbers and reflectors, energy-conserving heat mirrors, and antistatic coatings.

  13. Conductor shears as iceberg encroaches

    SciTech Connect

    Not Available

    1984-10-01

    Operators in the Arctic regions must protect wellheads from encroaching icebergs and icepack sheets. Diverting ice masses and excavating large holes below scour depth is expensive. Now an alternate approach allows the conductor to shear, shuts in the well, and provides a method of re-entering the well. The new system has been successfully used by Mobil on two exploratory wells in the Hibernia field off eastern Canada. The wells used 18 3/4-in. wellheads rated at 10,000 psi with 36-in. conductor pipe. The performance of the system is discussed.

  14. Quartz antenna with hollow conductor

    DOEpatents

    Leung, Ka-Ngo; Benabou, Elie

    2002-01-01

    A radio frequency (RF) antenna for plasma ion sources is formed of a hollow metal conductor tube disposed within a glass tube. The hollow metal tubular conductor has an internal flow channel so that there will be no coolant leakage if the outer glass tube of the antenna breaks. A portion of the RF antenna is formed into a coil; the antenna is used for inductively coupling RF power to a plasma in an ion source chamber. The antenna is made by first inserting the metal tube inside the glass tube, and then forming the glass/metal composite tube into the desired coil shape.

  15. 46 CFR 111.15-20 - Conductors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each...

  16. 46 CFR 111.15-20 - Conductors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each...

  17. 46 CFR 111.15-20 - Conductors.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each...

  18. 46 CFR 111.15-20 - Conductors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each...

  19. 46 CFR 111.15-20 - Conductors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... REQUIREMENTS Storage Batteries and Battery Chargers: Construction and Installation § 111.15-20 Conductors. (a) Each conductor penetration to a battery room must be made watertight. (b) The termination of each...

  20. Computer simulation of superionic conductors: II. Cationic conductors. Review

    SciTech Connect

    Ivanov-Shitz, A. K.

    2007-03-15

    The state of the art of the molecular-dynamics simulation of superionic conductors is reviewed. The main studies devoted to the structural, dynamic, and transport properties of the basic classes of solid electrolytes with conductivity via silver, copper, lithium, sodium, and hydrogen cations are considered. The premelting effect in ionic crystals is discussed.

  1. 33 CFR 159.73 - Conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Conductors. 159.73 Section 159.73 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.73 Conductors. Current carrying conductors must...

  2. 33 CFR 159.73 - Conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Conductors. 159.73 Section 159.73 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.73 Conductors. Current carrying conductors must...

  3. 33 CFR 159.73 - Conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Conductors. 159.73 Section 159.73 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.73 Conductors. Current carrying conductors must...

  4. 33 CFR 159.73 - Conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Conductors. 159.73 Section 159.73 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.73 Conductors. Current carrying conductors must...

  5. 33 CFR 159.73 - Conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Conductors. 159.73 Section 159.73 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.73 Conductors. Current carrying conductors must...

  6. Interfacing liquid metals with stretchable metal conductors.

    PubMed

    Kim, Bongsoo; Jang, Jaehyeok; You, Insang; Park, Jaeyoon; Shin, SangBaie; Jeon, Gumhye; Kim, Jin Kon; Jeong, Unyong

    2015-04-22

    Highly stretchable conductors are essential components in deformable electronics. Owing to their high stretchability and conductivity, liquid metals have attracted significant attention for use as circuits and interconnections. However, their poor wettability to stretchable metal electrodes prevents the formation of stable electrical connections. This study examined two approaches for creating a stable interface between a liquid metal (EGaIn) and stretchable metal electrodes via: (i) the use of honeycomb-structured stretchable metal electrodes and (ii) the addition of a conducting polymer interlayer. The line width of the honeycomb had a significant influence on the formation of a stable interface. The liquid metal formed a stable film layer on honeycomb metal electrodes, which have line widths of less than 50 μm. Coating PSS with a nonionic surfactant lowered the interfacial energy of EGaIn with flat stretchable metal surfaces; hence EGaIn was coated uniformly on the stretchable metal surfaces. Strain sensors were fabricated as a demonstrative example of an application that utilizes the stable interface.

  7. 75 FR 69165 - Conductor Certification

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-10

    ... who meet minimum Federal safety standards serve as conductors, to reduce the rate and number of... trained, in accordance with the training standards developed pursuant to section 20162. Section 20163(b... leading experts on a given subject, FRA is often favorably inclined toward the RSAC...

  8. Preparing the Conductor as Teacher

    ERIC Educational Resources Information Center

    Ulrich, Jerry

    2009-01-01

    While music is as old as humanity, conducting as a profession is relatively new. Although a nineteenth-century model has served as the template for the training of conductors, many undergraduate conducting students will spend their teaching careers working with inexperienced and/or amateur musicians. Additionally, the size of many ensembles in…

  9. Preparing the Conductor as Teacher

    ERIC Educational Resources Information Center

    Ulrich, Jerry

    2009-01-01

    While music is as old as humanity, conducting as a profession is relatively new. Although a nineteenth-century model has served as the template for the training of conductors, many undergraduate conducting students will spend their teaching careers working with inexperienced and/or amateur musicians. Additionally, the size of many ensembles in…

  10. Flat conductor cable design, manufacture, and installation

    NASA Technical Reports Server (NTRS)

    Angele, W.; Hankins, J. D.

    1973-01-01

    Pertinent information for hardware selection, design, manufacture, and quality control necessary for flat conductor cable interconnecting harness application is presented. Comparisons are made between round wire cable and flat conductor cable. The flat conductor cable interconnecting harness systems show major cost, weight, and space savings, plus increased system performance and reliability. The design application section includes electrical characteristics, harness design and development, and a full treatise on EMC considerations. Manufacturing and quality control sections pertain primarily to the developed conductor-contact connector system and special flat conductor cable to round wire cable transitions.

  11. Critical current measurement of commercial REBCO conductors at 4.2 K

    NASA Astrophysics Data System (ADS)

    Tsuchiya, K.; Kikuchi, A.; Terashima, A.; Norimoto, K.; Uchida, M.; Tawada, M.; Masuzawa, M.; Ohuchi, N.; Wang, X.; Takao, T.; Fujita, S.

    2017-07-01

    REBCO coated conductors are now available from several industrial manufacturers and are expected to be promising conductors for high-field-magnet applications. Using these conductors, the development of solenoids capable of generating high magnetic fields of 20-30 T is ongoing in major high-field laboratories in the world. In addition, CERN recently launched a conceptual design study for the Future Circular Collider, in which a 20-T dipole magnet is listed as a candidate for the bending magnet of the main ring. However, there has been limited research published on the electrical transport properties of commercially available REBCO conductors in a high-field, low-temperature environment. For magnet designers, the transport properties are of the highest importance in choosing a suitable conductor, and the data form the bases for high-field magnet development. Therefore, in this work, a new sample holder, which allows the measurements of full-width conductors to be carried out relatively easily, was developed, and the transport properties of commercial REBCO conductors from seven manufacturers (AMSC, Fujikura, Shanghai Superconductor, SuNAM, SuperOx, SuperPower, and SWCC Showa) were investigated at 4.2 K in perpendicular fields of up to 18 T. The results show that the Ic values at 4.2 K clearly vary to some extent among these commercial conductors and the higher-current 4-mm-wide conductors have Ic values in the range of 230-305 A at 18 T and in the range of 320-424 A at 12 T.

  12. Temperature limited heater utilizing non-ferromagnetic conductor

    DOEpatents

    Vinegar,; Harold J. , Harris; Kelvin, Christopher [Houston, TX

    2012-07-17

    A heater is described. The heater includes a ferromagnetic conductor and an electrical conductor electrically coupled to the ferromagnetic conductor. The ferromagnetic conductor is positioned relative to the electrical conductor such that an electromagnetic field produced by time-varying current flow in the ferromagnetic conductor confines a majority of the flow of the electrical current to the electrical conductor at temperatures below or near a selected temperature.

  13. Perovskite solar cells with CuI inorganic hole conductor

    NASA Astrophysics Data System (ADS)

    Takahashi, Kenta; Suzuki, Yoshikazu

    2017-08-01

    An organic material, 2,2‧,7,7‧-tetrakis(N,N-di-p-methoxyphenylamine)9,9‧-spirobifluorene (spiro-OMeTAD), is generally used as a hole conductor of perovskite solar cells (PSCs), but spiro-OMeTAD is much more expensive than other materials used in PSCs. In this study, we have prepared PSCs with a cost-effective CuI hole transport layer by spin coating. The merit of using spin coating for CuI is good compatibility with other steps, such as spin coating of a TiO2 electron transport layer and a perovskite active layer. The CuI-based PSC recorded power conversion efficiencies of η = 2.22% (max) on the day of production and η = 6.52% (max) after the 20 days of production. Moreover, the CuI-based PSC had a smaller hysteresis than the spiro-based PSC, suggesting that CuI is a highly promising alternative hole conductor for PSCs.

  14. Method for making conductors for ferrite memory arrays. [from pre-formed metal conductors

    NASA Technical Reports Server (NTRS)

    Heckler, C. H.; Baba, P. D.; Bhiwandker, N. C. (Inventor)

    1974-01-01

    The ferrite memory arrays are made from pre-formed metal conductors for the ferrite arrays. The conductors are made by forming a thin sheet of a metallizing paste of metal alloy powder, drying the paste layer, bisque firing the dried sheet at a first temperature, and then punching the conductors from the fired sheet. During the bisque firing, the conductor sheet shrinks to 58 percent of its pre-fired volume and the alloy particles sinter together. The conductors are embedded in ferrite sheet material and finally fired at a second higher temperature during which firing the conductors shrink approximately the same degree as the ferrite material.

  15. Thermoelectric Conversion with Ion Conductors

    DTIC Science & Technology

    1990-01-01

    compressor leg of the OHE. This material is known to be a good oxygen ion conductor at fairly low temperatures (1,4,5,6). Various dopants were wet mixed with...temperature. The calcined materials were additionally milled to effect particle size reduction and increase sinterability. Calcined powders were examined by...x-ray diffraction. After confirmation that this material was the highly oxygen conductive face centered cubic phase (denoted f -bismuth oxide

  16. Tetrathiapentalene-based organic conductors

    PubMed Central

    Misaki, Yohji

    2009-01-01

    The synthesis, structure and properties of tetrathiapentalene-based (TTP) organic conductors are reviewed. Among various TTP-type donors, bis-fused tetrathiafulvalene, 2,5-bis(1,3-dithiol-2-ylidene)-1,3,4,6-tetrathiapentalene (BDT-TTP) and its derivatives afford many metallic radical cation salts stable down to low temperatures, regardless of the size and shape of the counter anions. Most BDT-TTP conductors have a β-type donor arrangement with almost uniform stacks. Introduction of appropriate substituents results in molecular packing that differs from the β-type. A vinylogous TTP, 2-(1,3-dithiol-2-ylidene)-5-(2-ethanediylidene-1,3-dithiole)-1,3,4,6-tetrathiapentalene (DTEDT) has yielded an organic superconductor (DTEDT)3Au(CN)2 as well as metallic radical cation salts, regardless of the counter anions. (Thio)pyran analogs of TTP, namely (T)PDT-TTP and its derivatives produce molecular conductors with novel molecular arrangements. A TTP analog with reduced π-electron system 2,5-bis(1,3-dithian-2-ylidene)-1,3,4,6-tetrathiapentalene (BDA-TTP) has afforded several organic superconductors. Highly conducting molecular metals with unusual oxidation states (+1, +5/3 and neutral) have been developed on the basis of 2,5-bis(1,3-dithiol-2-ylidene)-1,3,4,6-tetrathiapentalene (BDT-TTP) derivatives and analogous metal derivatives M(dt)2 (M = Ni, Au). PMID:27877274

  17. Rapid doubling of the critical current of YBa{sub 2}Cu{sub 3}O{sub 7−δ} coated conductors for viable high-speed industrial processing

    SciTech Connect

    Leroux, M.; Welp, U.; Kwok, W.-K.; Kihlstrom, K. J.; Holleis, S.; Rupich, M. W.; Sathyamurthy, S.; Fleshler, S.; Sheng, H. P.; Miller, D. J.; Eley, S.; Civale, L.; Kayani, A.; Niraula, P. M.

    2015-11-09

    We demonstrate that 3.5-MeV oxygen irradiation can markedly enhance the in-field critical current of commercial second generation superconducting tapes with an exposure time of just 1 s per 0.8 cm{sup 2}. The speed demonstrated here is now at the level required for an industrial reel-to-reel post-processing. The irradiation is made on production line samples through the protective silver coating and does not require any modification of the growth process. From TEM imaging, we identify small clusters as the main source of increased vortex pinning.

  18. Rapid doubling of the critical current of Yba{sub 2}Cu{sub 3}O{sub 7-{delta}} coated conductor for viable high-speed industrial processing.

    SciTech Connect

    Leroux, M.; Kihlstrom, K. J.; Holleis, S.; Rupich, M. W.; Sathyamurthy, S.; Fleshler, S.; Sheng, H. P.; Miller, D. J.; Eley, S.; Civale, L.; Kayani, A.; Niraula, P. M.; Welp, U.; Kwok, W. -K.

    2015-11-09

    We demonstrate that 3.5-MeV oxygen irradiation can markedly enhance the in-field critical current of commercial 2nd generation superconducting tapes with an exposure time of just one second per 0.8 cm2. The speed demonstrated here is now at the level required for an industrial reel-to-reel post-processing. The irradiation is made on production line samples through the protective silver coating and does not require any modification of the growth process. From TEM imaging, we identify small clusters as the main source of increased vortex pinning.

  19. Rapid doubling of the critical current of YBa2Cu3O7-δ coated conductors for viable high-speed industrial processing

    SciTech Connect

    Leroux, M.; Kihlstrom, K. J.; Holleis, S.; Rupich, M. W.; Sathyamurthy, S.; Fleshler, S.; Sheng, H. P.; Miller, D. J.; Eley, S.; Civale, L.; Kayani, A.; Niraula, P. M.; Welp, U.; Kwok, W. -K.

    2015-11-09

    Here, we demonstrate that 3.5-MeV oxygen irradiation can markedly enhance the in-field critical current of commercial second generation superconducting tapes with an exposure time of just 1 s per 0.8 cm2. Furthermore we demonstrate how speed is now at the level required for an industrial reel-to-reel post-processing. The irradiation is made on production line samples through the protective silver coating and does not require any modification of the growth process. From TEM imaging, we identify small clusters as the main source of increased vortex pinning.

  20. Protective riser-conductor for offshore structures

    SciTech Connect

    Rutherford, D. A.; Albers, G. P.

    1985-07-09

    A protective sleeve for fitting about the periphery of the leg of an offshore structure. The sleeve comprises means for carrying and enclosing a plurality of conductors. It further includes one or more inner rings; an outer jacket is fixedly spaced from the rings to define longitudinal passages within which the respective conductors are fixedly positioned. The sleeve is capable of deflecting packed ice and floating objects which represent possible sources of damage to the structure or to conductors.

  1. Ultra-stretchable conductors based on buckled super-aligned carbon nanotube films

    NASA Astrophysics Data System (ADS)

    Yu, Yang; Luo, Shu; Sun, Li; Wu, Yang; Jiang, Kaili; Li, Qunqing; Wang, Jiaping; Fan, Shoushan

    2015-05-01

    Ultra-stretchable conductors are fabricated by coating super-aligned carbon nanotube (SACNT) films on pre-strained polydimethylsiloxane (PDMS) substrates and forming buckled SACNT structures on PDMS after release of the pre-strain. The parallel SACNT/PDMS conductors demonstrate excellent stability with normalized resistance changes of only 4.1% under an applied strain as high as 200%. The SACNT/PDMS conductors prepared with cross-stacked SACNT films show even lower resistance variation. The parallel SACNT/PDMS conductors exhibit high durability with a resistance increase of less than 5% after 10 000 cycles at 150% strain. In situ microscopic observations demonstrate that the buckled SACNT structures are straightened during the stretching process with reversible morphology evolution and thus the continuous SACNT conductive network can be protected from fracture. Due to the excellent electrical and mechanical properties of SACNT films and the formation of the buckled structure, SACNT/PDMS films exhibit high stretchability and durability, possessing great potential for use as ultra-stretchable conductors for wearable electronics, sensors, and energy storage devices.Ultra-stretchable conductors are fabricated by coating super-aligned carbon nanotube (SACNT) films on pre-strained polydimethylsiloxane (PDMS) substrates and forming buckled SACNT structures on PDMS after release of the pre-strain. The parallel SACNT/PDMS conductors demonstrate excellent stability with normalized resistance changes of only 4.1% under an applied strain as high as 200%. The SACNT/PDMS conductors prepared with cross-stacked SACNT films show even lower resistance variation. The parallel SACNT/PDMS conductors exhibit high durability with a resistance increase of less than 5% after 10 000 cycles at 150% strain. In situ microscopic observations demonstrate that the buckled SACNT structures are straightened during the stretching process with reversible morphology evolution and thus the continuous

  2. Effect of Conductor Verbalization, Dynamic Markings, Conductor Gesture, and Choir Dynamic Level on Singers' Dynamic Responses.

    ERIC Educational Resources Information Center

    Skadsem, Julie A.

    1997-01-01

    Examines the effects of conductor verbalization, dynamic markings, conductor gesture, and choir dynamic level on individual singers' dynamic responses. Indicates that verbal instructions from the conductor elicited significantly stronger dynamic performance responses than did the other instructional conditions. Suggests that additional research…

  3. Precision gold conductors for HMCs

    NASA Astrophysics Data System (ADS)

    Widmer, M. R.

    1994-08-01

    Ti/Pd/Au multiple code coded switch (MCCS) networks were built and compared to Cr/Au MCCS networks. The data showed no measurable difference between the two systems. Interface resistance of both types of networks was measured as a diagnostic aid to determine if hydrogen was affecting the Ti/Pd/Au MCCS networks. The data showed that although hydrogen does affect Ti/Pd/Au, the changes are not significant with respect to MCCS environments. An evaluation of several proprietary gold electroplating solutions for use in the production of Ti/Pd/Au conductors was performed. All the testing results were comparable to the current product requirements.

  4. Ag Nanowire Based Transparent Conductor for CIGS PV

    SciTech Connect

    Woods, L. M.; Wolk, J.; Smith, M.; Davande, H.; Ribelin, R. M.; Perkins, C. L.

    2011-01-01

    Coated silver nanowires (AgNW) have been considered as a replacement for transparent conducting oxides (TCOs) in CIGS based photovoltaic devices. The advantages of AgNW over TCOs are discussed, and optical and electrical characteristics of AgNWs on glass are presented. Similarly fabricated AgNWs with varying sheet resistance on CIGS devices were tested against ITO transparent conductor controls. The CIGS was produced using a roll-to-roll technique on a flexible polymer substrate. Variations in the ZnO layer resistivity that are adjacent to the AgNW layer in the CIGS device were also tested. Device results indicate similar Jsc, but a reduced FF for cells made with the AgNWs, and Voc dependence on the resistivity of the coated AgNW and ZnO window layers. FF and Voc losses associated with the use of AgNWs are discussed.

  5. Solid-state proton conductors

    NASA Astrophysics Data System (ADS)

    Jewulski, J. R.; Osif, T. L.; Remick, R. J.

    1990-12-01

    The purpose of this program was to survey the field of solid-state proton conductors (SSPC), identify conductors that could be used to develop solid-state fuel cells suitable for use with coal derived fuel gases, and begin the experimental research required for the development of these fuel cells. This document covers the following topics: the history of developments and current status of the SSPC, including a review of proton conducting electrolyte structures, the current status of the medium temperature SSPC development, electrodes for moderate temperature (SSPC) fuel cell, basic material and measurement techniques applicable for SSPC development, modeling, and optimization studies. Correlation and optimization studies are described which include correlation studies on proton conduction and oxide cathode optimization for the SSPC fuel cell. Experiments with the SSPC fuel cells are presented which include the fabrication of the electrolyte disks, apparatus for conducting measurements, the strontium-cerium based electrolyte, the barium-cerium based electrolyte with solid foil electrodes, the barium-cerium based electrolyte with porous electrodes, and conduction mechanisms.

  6. Solid-state proton conductors

    SciTech Connect

    Jewulski, J.R.; Osif, T.L.; Remick, R.J.

    1990-12-01

    The purpose of this program was to survey the field of solid-state proton conductors (SSPC), identify conductors that could be used to develop solid-state fuel cells suitable for use with coal derived fuel gases, and begin the experimental research required for the development of these fuel cells. This document covers the following topics: the history of developments and current status of the SSPC, including a review of proton conducting electrolyte structures, the current status of the medium temperature SSPC development, electrodes for moderate temperature (SSPC) fuel cell, basic material and measurement techniques applicable for SSPC development, modeling and optimization studies. Correlation and optimization studies, to include correlation studies on proton conduction and oxide cathode optimization for the SSPC fuel cell. Experiments with the SSPC fuel cells including the fabrication of the electrolyte disks, apparatus for conducting measurements, the strontium-cerium based electrolyte, the barium-cerium based electrolyte with solid foil electrodes, the barium-cerium based electrolyte with porous electrodes, and conduction mechanisms. 164 refs., 27 figs., 13 tabs.

  7. 33 CFR 183.425 - Conductors: General.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... than 30 inches. (g) This section does not apply to communications systems; electronic navigation equipment; electronic circuits having a current flow of less than one ampere; conductors which are totally inside an equipment housing; resistance conductors that control circuit amperage; high voltage secondary...

  8. 33 CFR 183.425 - Conductors: General.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... than 30 inches. (g) This section does not apply to communications systems; electronic navigation equipment; electronic circuits having a current flow of less than one ampere; conductors which are totally inside an equipment housing; resistance conductors that control circuit amperage; high voltage secondary...

  9. 33 CFR 183.425 - Conductors: General.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... than 30 inches. (g) This section does not apply to communications systems; electronic navigation equipment; electronic circuits having a current flow of less than one ampere; conductors which are totally inside an equipment housing; resistance conductors that control circuit amperage; high voltage secondary...

  10. Superionic Conductors as Fast, Repetitive Opening Switches

    DTIC Science & Technology

    1988-06-06

    an unexpected effect was found’ in a fast-ion conductor ("superionic" conductor) Ag1 319W208 : The electrical condutivity decreased by approximately... thermal one. The process was observed to be highly reversible, though not completely so, since neutral Ago was seen to plate out on the surface of the AgI

  11. Doped LZO buffer layers for laminated conductors

    DOEpatents

    Paranthaman, Mariappan Parans [Knoxville, TN; Schoop, Urs [Westborough, MA; Goyal, Amit [Knoxville, TN; Thieme, Cornelis Leo Hans [Westborough, MA; Verebelyi, Darren T [Oxford, MA; Rupich, Martin W [Framingham, MA

    2010-03-23

    A laminated conductor includes a metallic substrate having a surface, a biaxially textured buffer layer supported by the surface of the substrate, the biaxially textured buffer layer comprising LZO and a dopant for mitigating metal diffusion through the LZO, and a biaxially textured conductor layer supported by the biaxially textured buffer layer.

  12. 33 CFR 183.425 - Conductors: General.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... than 30 inches. (g) This section does not apply to communications systems; electronic navigation equipment; electronic circuits having a current flow of less than one ampere; conductors which are totally inside an equipment housing; resistance conductors that control circuit amperage; high voltage secondary...

  13. 33 CFR 183.425 - Conductors: General.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... than 30 inches. (g) This section does not apply to communications systems; electronic navigation equipment; electronic circuits having a current flow of less than one ampere; conductors which are totally inside an equipment housing; resistance conductors that control circuit amperage; high voltage secondary...

  14. Superconducting-magnetic heterostructures: a method of decreasing AC losses and improving critical current density in multifilamentary conductors.

    PubMed

    Glowacki, B A; Majoros, M

    2009-06-24

    Magnetic materials can help to improve the performance of practical superconductors on the macroscale/microscale as magnetic diverters and also on the nanoscale as effective pinning centres. It has been established by numerical modelling that magnetic shielding of the filaments reduces AC losses in self-field conditions due to decoupling of the filaments and, at the same time, it increases the critical current of the composite. This effect is especially beneficial for coated conductors, in which the anisotropic properties of the superconductor are amplified by the conductor architecture. However, ferromagnetic coatings are often chemically incompatible with YBa(2)Cu(3)O(7) and (Pb,Bi)(2)Sr(2)Ca(2)Cu(3)O(9) conductors, and buffer layers have to be used. In contrast, in MgB(2) conductors an iron matrix may remain in direct contact with the superconducting core. The application of superconducting-magnetic heterostructures requires consideration of the thermal and electromagnetic stability of the superconducting materials used. On one hand, magnetic materials reduce the critical current gradient across the individual filaments but, on the other hand, they often reduce the thermal conductivity between the superconducting core and the cryogen, which may cause destruction of the conductor in the event of thermal instability. A possible nanoscale method of improving the critical current density of superconducting conductors is the introduction of sub-micron magnetic pinning centres. However, the volumetric density and chemical compatibility of magnetic inclusions has to be controlled to avoid suppression of the superconducting properties.

  15. Molten carbonate fuel cell cathode with mixed oxide coating

    DOEpatents

    Hilmi, Abdelkader; Yuh, Chao-Yi

    2013-05-07

    A molten carbonate fuel cell cathode having a cathode body and a coating of a mixed oxygen ion conductor materials. The mixed oxygen ion conductor materials are formed from ceria or doped ceria, such as gadolinium doped ceria or yttrium doped ceria. The coating is deposited on the cathode body using a sol-gel process, which utilizes as precursors organometallic compounds, organic and inorganic salts, hydroxides or alkoxides and which uses as the solvent water, organic solvent or a mixture of same.

  16. History of crystalline organic conductor

    NASA Astrophysics Data System (ADS)

    Murata, Keizo

    2017-05-01

    A brief view of crystalline organic conductor is presented. Since the discovery of TTF-TCNQ (tetrathiafulvalene-tetracyanoquinodimethane) in the mid 1970’s, pressure has been an indispensable tool to develop the physics of this field. From the aspect of charge transfer salt, TTF-TCNQ and its family was specified with partial charge transfer, two chain one-dimensional (1D) system, charge density wave (CDW) and commensurability. On the other hand, in (TMTSF)2X family (TMTSF: tetramethyltetraselenafulvalene, X: electron acceptor such as PF6, ClO4), complete charge transfer, one chain system, spin density wave (SDW), field-induced SDW, quantum Hall effect, superconductivity were discussed. Further, together with pressure itself, cooling rate was noticed to be important for low temperature properties. Recently, coming back to TTF-TCNQ family, i.e., HMTSF-TCNQ, whether or not field-induced CDW, instead of field-induced SDW, and quantum Hall effect is present was discussed (HMTSF: hexamethylene-tetraselenafulvalene). Whether or not the Fermiology in (TMTTF)2X under pressure is similar to that of (TMTSF)2X is discussed as well. In (BEDT-TTF)2X, new aspect of macroscopic polarization of α-(BEDT-TTF)2I3 related to charge order is described. At the end, in contrast to the charge transfer salts, non-charge transfer salt, that is, single component conductor is presented as a new possible example of Dirac cone, which was deeply studied by many researchers in α-(BEDT-TTF)2I3, together with the theoretical calculation of its magnetic susceptibility (BEDT-TTF: bisethylenedithia-tetrathiafulvalene).

  17. Frontiers of organic conductors and superconductors.

    PubMed

    Saito, Gunzi; Yoshida, Yukihiro

    2012-01-01

    We review the development of conductive organic molecular assemblies including organic metals, superconductors, single component conductors, conductive films, conductors with a switching function, and new spin state (quantum spin liquid state). We emphasize the importance of the ionicity phase diagram for a variety of charge transfer systems to provide a strategy for the development of functional organic solids (Mott insulator, semiconductor, superconductor, metal, complex isomer, neutral-ionic system, alignment of chemical potentials, etc.). For organic (super)conductors, the electronic dimensionality of the solids is a key parameter and can be designed based on the self-aggregation ability of a molecule. We present characteristic structural and physical properties of organic superconductors.

  18. An Exploratory Comparison of Novice, Intermediate, and Expert Orchestral Conductors

    ERIC Educational Resources Information Center

    Bergee, Martin J.

    2005-01-01

    This study compared novice, "intermediate" (graduate student), and expert orchestral conductors. Two novice conductors, one graduate student in orchestral conducting, and one expert conductor led a university symphony orchestra in part of the first movement of Brahms's Symphony No. 2. Wired for sound, conductors attempted to verbalize their…

  19. Development of a REBa2Cu3O7-δ multi-core superconductor with ‘inner split’ technology

    NASA Astrophysics Data System (ADS)

    Jin, Xinzhe; Oguro, Hidetoshi; Oshima, Yugo; Matsuda, Tetsuro; Maeda, Hideaki

    2016-04-01

    Recently, advanced research into fine filament technology for tape-shaped superconducting-coated conductors composed of REBa2Cu3O7-δ (RE123, RE: rare earth such as Gd or Y, 0 < δ < 1) has been carried out to improve performance in high magnetic fields by reducing the large diamagnetism of the RE123 superconducting layer. The major challenge for high-field NMR/MRI applications is to obtain high tensile stress tolerance above 500 MPa with a high critical current. In this study, a RE123 multi-core superconductor was fabricated via an ‘inner split’ method using a commercially available RE123 single-core coated conductor, where only the ceramics (RE123 and buffer layers) in wire are electrically separated to multi-filaments without superconducting current flow between the filaments. Experimental results show that wires having 2, 3, 4, or 5 cores have a high critical current (above 95% of the original) and maintain tensile stress tolerance above 650 MPa. The diamagnetism of the five-core wire is reduced ˜85% of the original at 7 T. Thus, the wire was optimized via inner split method for high-field use.

  20. Contribution of ethylenetetrafluoroethylene (ETFE) insulation to the electrical performance of Riata® silicone leads having externalized conductors.

    PubMed

    Fischer, Avi; Klehn, Russell

    2013-08-01

    The insulation of St. Jude Medical Riata® leads contains a polytetrafluoroethylene (PTFE) liner, silicone tubing, and ethylenetetrafluoroethylene (ETFE) coating on individual cable conductors. ETFE has sufficient dielectric strength to assure electrical function. This investigation intended to analyze performance of leads with and without externalized conductors and with intact and breached ETFE. Testing was performed on ETFE-coated conductors to determine their ability to deliver high-voltage therapy. Tests were performed on samples under different conditions and current leakage was measured. A high-voltage test and a cyclic pulse test were performed, and the effect of lead modifications on the potential gradient from a high-voltage shock was used to determine functionality. Measurements from modified Riata® leads were compared with a control lead with all insulation and conducting elements intact. Current leakage for all conditions tested, was within the acceptance criteria for the high-voltage test and the cyclic pulse test. In conductors that underwent cyclic testing, the highest value of current leakage was within the limit of acceptability for both phases of the test. Testing of leads with externalized conductors and breached ETFE showed similar potential gradients compared with a control lead. Testing of ETFE-coated conductors following multiple preconditioning steps showed that ETFE serves as a redundant layer of insulation. In the event that the ETFE coating is breached, the potential gradient seen resulting from a high-voltage defibrillation shock was similar to a lead with no breach to the ETFE, even after 100 shocks.

  1. The manufacture of flat conductor cable

    NASA Technical Reports Server (NTRS)

    Angele, W.

    1974-01-01

    The major techniques are described for fabricating flat conductor cable (FCC). Various types of FCC, including unshielded, shielded, power, and signal, in both existing and conceptual constructions, are covered.

  2. Conductor Development for High Field Dipole Magnets

    SciTech Connect

    Scanlan, R.M.; Dietderich, D.R.; Higley, H.C.

    2000-03-01

    Historically, improvements in dipole magnet performance have been paced by improvements in the superconductor available for use in these magnets. The critical conductor performance parameters for dipole magnets include current density, piece length, effective filament size, and cost. Each of these parameters is important for efficient, cost effective dipoles, with critical current density being perhaps the most important. Several promising magnet designs for the next hadron collider or a muon collider require fields of 12 T or higber, i.e. beyond the reach of NbTi. The conductor options include Nb{sub 3}Sn, Nb{sub 3}Al, or the high temperature superconductors. Although these conductors have the potential to provide the combination of performance and cost required, none of them have been developed sufficiently at this point to satisfy all the requirements. This paper will review the status of each class of advanced conductor and discuss the remaining problems that require solutions before these new conductors can be considered as practical. In particular, the plans for a new program to develop Nb{sub 3}Sn and Nb{sub 3}Al conductors for high energy physics applications will be presented. Also, the development of a multikiloamp Bi-2212 cable for dipole magnet applications will be reported.

  3. Broadband dielectric spectroscopy of inhomogeneous and composite weak conductors

    NASA Astrophysics Data System (ADS)

    Petzelt, J.; Nuzhnyy, D.

    2016-08-01

    In this paper, we discuss broadband dielectric spectroscopy from mHz up to the infrared range mainly for materials with inhomogeneous weak conductivity, including conductor-dielectric nanocomposites. Our discussion is based on the effective medium approximation (EMA) and experiments modeled by this approach are reviewed. We discuss core-shell composites modeled by coated-spheres (Hashin-Shtrikman model) and normal composites with a possible percolation of the conductor component resulting in sharp or smeared percolation threshold of the DC conductivity and diverging static permittivity in the former case. The sharp percolation threshold is modeled by the Bruggeman EMA or by general EMA with arbitrary percolation threshold and arbitrary critical exponents of the DC conductivity and static permittivity. For the case of smeared percolation threshold in the case of complex topologies, we use the Lichtenecker model allowing for partial percolation of both the components. Finally, numerous papers reporting negative permittivity in weakly conducting materials are criticized and concluded to be due to spurious effects.

  4. Nonlinear electrochemical relaxation around conductors.

    PubMed

    Chu, Kevin T; Bazant, Martin Z

    2006-07-01

    We analyze the simplest problem of electrochemical relaxation in more than one dimension-the response of an uncharged, ideally polarizable metallic sphere (or cylinder) in a symmetric, binary electrolyte to a uniform electric field. In order to go beyond the circuit approximation for thin double layers, our analysis is based on the Poisson-Nernst-Planck (PNP) equations of dilute solution theory. Unlike most previous studies, however, we focus on the nonlinear regime, where the applied voltage across the conductor is larger than the thermal voltage. In such strong electric fields, the classical model predicts that the double layer adsorbs enough ions to produce bulk concentration gradients and surface conduction. Our analysis begins with a general derivation of surface conservation laws in the thin double-layer limit, which provide effective boundary conditions on the quasineutral bulk. We solve the resulting nonlinear partial differential equations numerically for strong fields and also perform a time-dependent asymptotic analysis for weaker fields, where bulk diffusion and surface conduction arise as first-order corrections. We also derive various dimensionless parameters comparing surface to bulk transport processes, which generalize the Bikerman-Dukhin number. Our results have basic relevance for double-layer charging dynamics and nonlinear electrokinetics in the ubiquitous PNP approximation.

  5. Effects of Conductor Baton Use on Band and Choral Musicians' Perceptions of Conductor Expressivity and Clarity

    ERIC Educational Resources Information Center

    Nápoles, Jessica; Silvey, Brian A.

    2017-01-01

    The purpose of this study was to examine participants' (college band and choral musicians, N = 143) perceptions of conductor clarity and expressivity after viewing band and choral directors conducting with or without a baton. One band and one choral conductor each prepared and conducted two excerpts of Guy Forbes's "O Nata Lux", a piece…

  6. Conductor load bearing roller for a gas-insulated transmission line having a corrugated outer conductor

    SciTech Connect

    Fischer, William H.; Yoon, Kue H.

    1984-04-10

    A gas-insulated transmission line includes a corrugated outer conductor, an inner conductor disposed within and insulated from the outer conductor by means of support insulators and an insulating gas, and a transport device for supporting and permitting movement of the inner conductor/insulating support assembly axially along the corrugated outer conductor without radial displacement. The transport device includes two movable contacts, such as skids or rollers, supported on a common pivot lever, the pivot lever being rotatably disposed about a pivot lever axis, which pivot lever axis is in turn disposed on the periphery of a support insulator or particle trap if one is used. The movable contacts are separated axially a distance equal to the axial distance between the peaks and valleys of the corrugations of the outer conductor and separated radially a distance equal to the radial distance between the peaks and valleys of the corrugations of the outer conductor. The transport device has the pivot lever axis disposed perpendicular to the direction of travel of the inner conductor/insulating support assembly.

  7. YBCO Coated Conductor with an Integrated Optical Fiber Sensor

    SciTech Connect

    Sathyamurthy, Srivatsan; Rupich, Marty; Schwartz, Justin

    2016-03-31

    The primary objectives of the Phase I Project was to develop a proof-of-principle for a concept of integrating an optical fiber sensor into the laminated 2G wire, there by producing a functionalized 2G wire with self-monitoring capabilities

  8. Incorporating YBCO Coated Conductors in High-speed Superconducting Generators

    DTIC Science & Technology

    2008-07-01

    4.0 kW/lb (8.82 kW/kg). The machine configuration chosen by GE for design was a homopolar inductor alternator (HIA) which locates the...extremely severe ac loss environment. Even if this is ultimately impossible for high speed generators, it may not preclude lower speed motors and

  9. Preparation of coated conductor architectures on Ni composite tapes

    NASA Astrophysics Data System (ADS)

    Hühne, R.; Subramanya Sarma, V.; Okai, D.; Thersleff, T.; Schultz, L.; Holzapfel, B.

    2007-07-01

    An epitaxial Y2O3/YSZ/CeO2 buffer architecture has been prepared using pulsed laser deposition on cube texture Ni-3 at.% W/Ni-10 at.% Cr-1.5 at.% Al and Ni-5 at.% W/Ni-10 at.% W composite tapes. The buffer layer growth was studied in detail and revealed good texture transfer throughout the structure, similar to standard Ni-5 at.% W substrates. YBCO layers were successfully deposited on the buffered tapes and compared to films grown on SrTiO3 single crystals. A superconducting transition temperature of about 90 K with a small transition width was observed on all metal substrates. A critical current density Jc of about 1 MA cm-2 was measured at 77 K in a self-field. It was found that Jc is mainly limited by the grain boundary network in magnetic fields below 4 T, whereas similar values as on SrTiO3 single crystals were measured at higher fields.

  10. Material Science and Physics of High-IC Coated Conductors

    DTIC Science & Technology

    2009-08-02

    defects as shown in Fig. 1. Two schemes have been explored in details. One is to chop vortices to shorter pieces in a multilayer YBCO/ CeO2 structure...distributed point defects (black), decoupled into two identical segments in a trilayered YBCO/ CeO2 /YBCO (red) and an ideal solution to eliminate Jc−t by...Materials 96, 2136 (2006) 23. X. Wang and J.Z. Wu, “Effect of magnetic coupling on the Jc of YBa2Cu3O7-x/ CeO2 / YBa2Cu3O7-x trilayers”, Appl. Phys. Lett. 88, 062513(2006). Also in virtual journal of superconductivity.

  11. Transverse Resistivity of YBCO Coated Conductors for AC Use

    DTIC Science & Technology

    2005-10-01

    thanks the Alexander von Humboldt Foundation for the support of the work. References [1] P. N. Barnes, G. L. Rhoads, J. C. Tolliver, M. D... Alexander von Humboldt Foundation for the support. M. P., E. D., L. J., E. U, are with the Institute of Electrical Engineering, Slovak Academy of...E+04 -3,E+04 -2,E+04 -1,E+04 0,E+00 1,E+04 2,E+04 3,E+04 -1,E-02 -5,E-03 0,E+00 5,E-03 1,E-02 x,m cu rr en t, A /m zero field 36,5mT * Fig.1b

  12. CHEMICAL SOLUTION DEPOSITION BASED OXIDE BUFFERS AND YBCO COATED CONDUCTORS

    SciTech Connect

    Paranthaman, Mariappan Parans

    2011-01-01

    We have reviewed briefly the growth of buffer and high temperature superconducting oxide thin films using a chemical solution deposition (CSD) method. In the Rolling-Assisted Biaxially Textured Substrates (RABiTS) process, developed at Oak Ridge National Laboratory, utilizes the thermo mechanical processing to obtain the flexible, biaxially oriented copper, nickel or nickel-alloy substrates. Buffers and Rare Earth Barium Copper Oxide (REBCO) superconductors have been deposited epitaxially on the textured nickel alloy substrates. The starting substrate serves as a template for the REBCO layer, which has substantially fewer weak links. Buffer layers play a major role in fabricating the second generation REBCO wire technology. The main purpose of the buffer layers is to provide a smooth, continuous and chemically inert surface for the growth of the REBCO film, while transferring the texture from the substrate to the superconductor layer. To achieve this, the buffer layers need to be epitaxial to the substrate, i.e. they have to nucleate and grow in the same bi-axial texture provided by the textured metal foil. The most commonly used RABiTS multi-layer architectures consist of a starting template of biaxially textured Ni-5 at.% W (Ni-W) substrate with a seed (first) layer of Yttrium Oxide (Y2O3), a barrier (second) layer of Yttria Stabilized Zirconia (YSZ), and a Cerium Oxide (CeO2) cap (third) layer. These three buffer layers are generally deposited using physical vapor deposition (PVD) techniques such as reactive sputtering. On top of the PVD template, REBCO film is then grown by a chemical solution deposition. This article reviews in detail about the list of oxide buffers and superconductor REBCO films grown epitaxially on single crystal and/or biaxially textured Ni-W substrates using a CSD method.

  13. Infrared thermography and overloaded neutral conductors

    NASA Astrophysics Data System (ADS)

    McComb, John; Niebla, Hector E.

    1999-03-01

    Present findings of two recent case studies. One involves transformer failures on three computer-stores within eight hours of their grand opening. The second discusses the findings during an infrared thermography-training course for electric utility engineers of a transformer vault serving an industrial customer. Both of these deal with overloaded neutral conductors. Historically, the average neutral conductor carried only the imbalance of the current between the phases of a three-phase system. This current was typically small in relation to the load being served. In fact, for economic reasons many neutrals were installed smaller than their associated phase conductors. Today however, certain types of loads (non-linear loads such as computers) and certain transformer connections (4 bushing single phase with a collector bus) cause the neutral to have up to three times as much amperage as the phase conductors. This paper will discuss the conditions under which such loading occurs and further investigate steps that can be taken/recommended should an infrared test indicate an overloaded neutral conductor.

  14. Hydrate melting in soil around hot conductor

    SciTech Connect

    Briaud, J.L.; Chaouch, A.

    1997-07-01

    There is ice in the Gulf of Mexico, and this type of ice called gas hydrates burns when ignited. Gas hydrates form slowly within the soil mass when the gas seeping up from offshore oil reservoirs mixes with water under high pressures (>500 m of water) and low temperatures (a few degrees Celsius). The oil travels from the well to the platform through a conductor pipe. The oil and therefore the conductor are very hot and melt the existing hydrates that are within the depth of the foundation piles. The melting process generates a large amount of gas that can endanger the stability of the foundation. The rate at which the temperature rises around the hot conductor in the hydrate rich soil is studied using the finite-element method (FEM). A detailed thermodynamic analysis is performed. It includes a laboratory experiment to help validate FEM, a study of the mesh size, the thermodynamic analysis results, a study of the conductor size, and of the latent heat influence. The results can be used to evaluate the temperature rise around a hot pipe buried in soil and therefore the propagation of the hydrate melting front around the conductor and toward the piles.

  15. Thermal conductor for high-energy electrochemical cells

    DOEpatents

    Hoffman, Joseph A.; Domroese, Michael K.; Lindeman, David D.; Radewald, Vern E.; Rouillard, Roger; Trice, Jennifer L.

    2000-01-01

    A thermal conductor for use with an electrochemical energy storage device is disclosed. The thermal conductor is attached to one or both of the anode and cathode contacts of an electrochemical cell. A resilient portion of the conductor varies in height or position to maintain contact between the conductor and an adjacent wall structure of a containment vessel in response to relative movement between the conductor and the wall structure. The thermal conductor conducts current into and out of the electrochemical cell and conducts thermal energy between the electrochemical cell and thermally conductive and electrically resistive material disposed between the conductor and the wall structure. The thermal conductor may be fabricated to include a resilient portion having one of a substantially C-shaped, double C-shaped, Z-shaped, V-shaped, O-shaped, S-shaped, or finger-shaped cross-section. An elastomeric spring element may be configured so as to be captured by the resilient conductor for purposes of enhancing the functionality of the thermal conductor. The spring element may include a protrusion that provides electrical insulation between the spring conductor and a spring conductor of an adjacently disposed electrochemical cell in the presence of relative movement between the cells and the wall structure. The thermal conductor may also be fabricated from a sheet of electrically conductive material and affixed to the contacts of a number of electrochemical cells.

  16. Homogenization Modeling for Mechanical Properties of Composite Conductor With Cooling Channel

    NASA Astrophysics Data System (ADS)

    Sun, We; Tzeng, Jerome T.

    2002-11-01

    An electrical composite conductor may consist of a metallic core with a cooling channel and a multilayered insulating material. A model was developed to predict the mechanical properties of the composite conductor based on two-level homogenization hierarchies. A composite cylinder assembly model was developed in the level 1 homogenization for metallic core with a cooling channel, in which the cooling channel was analogized as a fiber void with null material properties. The effective mechanical properties of the composite insulation layers were homogenized by smearing the properties of the multiple polymer coatings and fiber-reinforced composite. In the level 2 homogenization, combined homogenization sequences were used based on the requirement of the displacement-or the traction-prescribed continuity. The developed model can calculate the nine effective mechanical constants of the conductor made of a metallic core and any angle (+00) plain-woven glass-fiber composite. The model predictions were compared well with the results obtained from the finite element analyses. The developed model provides a theoretical basis and an accurate calculation for effective mechanical constants that are often difficult to be accurately determined through an experimental approach due to the structural heterogeneity and material anisotropy of the composite conductor.

  17. Tunable Broadband Printed Carbon Transparent Conductor

    NASA Astrophysics Data System (ADS)

    Xu, Yue; Wan, Jiayu

    Transparent conductors have been widely applied in solar cells, transparent smart skins, and sensing/imaging antennas, etc. Carbon-based transparent conductor has attracted great attention for its low cost and broad range transparency. Ion intercalation has been known to highly dope graphitic materials, thereby tuning materials' optoelectronic properties. For the first time, we successfully tune the optical transmittance of a reduced graphene oxide (RGO)/CNT network from mid-IR range to visible range by means of Li-ion intercalation/deintercalation. We also observed a simultaneous increase of the electrical conductivity with the Li-ion intercalation. This printed carbon hybrid thin film was prepared through all solution processes and was easily scalable. This study demonstrates the possibility of using ion intercalation for low cost, tunable broadband transparent conductors.

  18. Quench propagation velocity for highly stabilized conductors

    SciTech Connect

    Mints, R.G. |; Ogitsu, T. |; Devred, A.

    1995-05-01

    Quench propagation velocity in conductors having a large amount of stabilizer outside the multifilamentary area is considered. It is shown that the current redistribution process between the multifilamentary area and the stabilizer can strongly effect the quench propagation. A criterion is derived determining the conditions under which the current redistribution process becomes significant, and a model of effective stabilizer area is suggested to describe its influence on the quench propagation velocity. As an illustration, the model is applied to calculate the adiabatic quench propagation velocity for a conductor geometry with a multifilamentary area embedded inside the stabilizer.

  19. Measuring the Magnetic Force on a Current-Carrying Conductor.

    ERIC Educational Resources Information Center

    Herreman, W.; Huysentruyt, R.

    1995-01-01

    Describes a fast and simple method for measuring the magnetic force acting on a current-carrying conductor using a digital balance. Discusses the influence of current intensity and wire length on the magnetic force on the conductor. (JRH)

  20. 30 CFR 75.513-1 - Electric conductor; size.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Electric conductor; size. An electric conductor is not of sufficient size to have adequate carrying capacity if it is smaller than is provided for in the National Electric Code, 1968. In addition,...

  1. 30 CFR 75.513-1 - Electric conductor; size.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Electric conductor; size. An electric conductor is not of sufficient size to have adequate carrying capacity if it is smaller than is provided for in the National Electric Code, 1968. In addition,...

  2. 30 CFR 75.513-1 - Electric conductor; size.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Electric conductor; size. An electric conductor is not of sufficient size to have adequate carrying capacity if it is smaller than is provided for in the National Electric Code, 1968. In addition,...

  3. Method and apparatus for preparing multiconductor cable with flat conductors

    NASA Technical Reports Server (NTRS)

    Marcell, G. V. (Inventor)

    1969-01-01

    A method and apparatus for preparing flat conductor cable having a plurality of ribbon-like conductors disposed upon and adhesively bonded to the surface of a substrate is described. The conductors are brought into contact with the substrate surface, and while maintained in axial tension on said substrate, the combination is seated on a yieldably compressible layer to permit the conductor to become embedded into the surface of the substrate film.

  4. 46 CFR 111.50-3 - Protection of conductors.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... of overcurrent protection for conductors is to open the electric circuit if the current reaches a... in each ungrounded conductor of the same circuit. (b) Overcurrent protection of conductors. Each... following circuits which must meet the following listed subparts of this chapter: (1) Propulsion...

  5. 46 CFR 111.50-3 - Protection of conductors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... of overcurrent protection for conductors is to open the electric circuit if the current reaches a... in each ungrounded conductor of the same circuit. (b) Overcurrent protection of conductors. Each... following circuits which must meet the following listed subparts of this chapter: (1) Propulsion...

  6. 46 CFR 111.50-3 - Protection of conductors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... of overcurrent protection for conductors is to open the electric circuit if the current reaches a... in each ungrounded conductor of the same circuit. (b) Overcurrent protection of conductors. Each... following circuits which must meet the following listed subparts of this chapter: (1) Propulsion...

  7. 46 CFR 111.50-3 - Protection of conductors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... of overcurrent protection for conductors is to open the electric circuit if the current reaches a... in each ungrounded conductor of the same circuit. (b) Overcurrent protection of conductors. Each... following circuits which must meet the following listed subparts of this chapter: (1) Propulsion...

  8. 46 CFR 111.50-3 - Protection of conductors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... of overcurrent protection for conductors is to open the electric circuit if the current reaches a... in each ungrounded conductor of the same circuit. (b) Overcurrent protection of conductors. Each... following circuits which must meet the following listed subparts of this chapter: (1) Propulsion...

  9. 30 CFR 77.503-1 - Electric conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric conductors. 77.503-1 Section 77.503-1... MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Electrical Equipment-General § 77.503-1 Electric conductors. Electric conductors shall be sufficient in size to meet...

  10. 30 CFR 77.503-1 - Electric conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric conductors. 77.503-1 Section 77.503-1... MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Electrical Equipment-General § 77.503-1 Electric conductors. Electric conductors shall be sufficient in size to meet...

  11. 33 CFR 159.71 - Electrical controls and conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Electrical controls and... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors must...

  12. 30 CFR 75.513-1 - Electric conductor; size.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric conductor; size. 75.513-1 Section 75... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.513-1 Electric conductor; size. An electric conductor is not of sufficient size to have adequate carrying...

  13. 33 CFR 159.71 - Electrical controls and conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Electrical controls and... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors must...

  14. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... § 56.12011 High-potential electrical conductors. High-potential electrical conductors shall be covered...

  15. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... § 56.12011 High-potential electrical conductors. High-potential electrical conductors shall be covered...

  16. 30 CFR 75.513-1 - Electric conductor; size.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric conductor; size. 75.513-1 Section 75... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.513-1 Electric conductor; size. An electric conductor is not of sufficient size to have adequate carrying...

  17. 46 CFR 120.372 - Equipment and conductor grounding.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Equipment and conductor grounding. 120.372 Section 120... INSTALLATION Power Sources and Distribution Systems § 120.372 Equipment and conductor grounding. (a) All... together to a common ground by a normally non-current carrying conductor. Metallic cases of instruments...

  18. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare power...

  19. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare power...

  20. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare power...

  1. 30 CFR 75.513 - Electric conductor; capacity and insulation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electric conductor; capacity and insulation. 75.513 Section 75.513 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... § 75.513 Electric conductor; capacity and insulation. All electric conductors shall be sufficient in...

  2. 30 CFR 75.513 - Electric conductor; capacity and insulation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric conductor; capacity and insulation. 75.513 Section 75.513 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... § 75.513 Electric conductor; capacity and insulation. All electric conductors shall be sufficient in...

  3. 30 CFR 75.513 - Electric conductor; capacity and insulation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electric conductor; capacity and insulation. 75.513 Section 75.513 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... § 75.513 Electric conductor; capacity and insulation. All electric conductors shall be sufficient in...

  4. 30 CFR 75.513 - Electric conductor; capacity and insulation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electric conductor; capacity and insulation. 75.513 Section 75.513 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... § 75.513 Electric conductor; capacity and insulation. All electric conductors shall be sufficient in...

  5. 30 CFR 75.513 - Electric conductor; capacity and insulation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric conductor; capacity and insulation. 75.513 Section 75.513 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL... § 75.513 Electric conductor; capacity and insulation. All electric conductors shall be sufficient in...

  6. 33 CFR 159.71 - Electrical controls and conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Electrical controls and... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors...

  7. 30 CFR 77.503-1 - Electric conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electric conductors. 77.503-1 Section 77.503-1... MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Electrical Equipment-General § 77.503-1 Electric conductors. Electric conductors shall be sufficient in size to...

  8. 30 CFR 77.503-1 - Electric conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electric conductors. 77.503-1 Section 77.503-1... MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Electrical Equipment-General § 77.503-1 Electric conductors. Electric conductors shall be sufficient in size to...

  9. 33 CFR 159.71 - Electrical controls and conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Electrical controls and... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors...

  10. 33 CFR 159.71 - Electrical controls and conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Electrical controls and... Electrical controls and conductors. Electrical controls and conductors must be installed in accordance with good marine practice. Wire must be copper and must be stranded. Electrical controls and conductors...

  11. 30 CFR 77.503-1 - Electric conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electric conductors. 77.503-1 Section 77.503-1... MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Electrical Equipment-General § 77.503-1 Electric conductors. Electric conductors shall be sufficient in size to...

  12. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare power...

  13. 30 CFR 57.12080 - Bare conductor guards.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Bare conductor guards. 57.12080 Section 57... Underground Only § 57.12080 Bare conductor guards. Trolley wires and bare power conductors shall be guarded at mantrip loading and unloading points, and at shaft stations. Where such trolley wires and bare...

  14. Full tape thickness feature conductors for EMI structures

    DOEpatents

    Peterson, Kenneth A.; Knudson, Richard T.; Smith, Frank R.; Barner, Gregory

    2014-06-10

    Generally annular full tape thickness conductors are formed in single or multiple tape layers, and then stacked to produce an annular solid conductive wall for enclosing an electromagnetic isolation cavity. The conductors may be formed using punch and fill operations, or by flowing conductor-containing material onto the tape edge surfaces that define the interior sidewalls of the cavity.

  15. Superconductor-coated carbon fiber composites

    SciTech Connect

    Statek, L.C.; Bennett, W.F.; Schulz, D.A.

    1990-12-04

    This patent describes superconducting composites made from ceramic-type superconductors coated onto a low resistivity carbon fiber selected from those high strength fibers which have an ultrahigh modulus and high thermal conductivity. Flexible conductors of several different structures made from such composites are described as well as other useful forms of the composites.

  16. 30 CFR 56.12004 - Electrical conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electrical conductors. 56.12004 Section 56.12004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  17. 30 CFR 57.12004 - Electrical conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electrical conductors. 57.12004 Section 57.12004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES...

  18. 30 CFR 56.12004 - Electrical conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electrical conductors. 56.12004 Section 56.12004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  19. 30 CFR 57.12004 - Electrical conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electrical conductors. 57.12004 Section 57.12004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES...

  20. 30 CFR 56.12004 - Electrical conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electrical conductors. 56.12004 Section 56.12004 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity §...

  1. The Seebeck coefficient of superionic conductors

    NASA Astrophysics Data System (ADS)

    Mahan, G. D.

    2015-01-01

    We present a theory of the anomalous Seebeck coefficient found in the superionic conductor Cu2Se. It has a phase transition at T = 400 K where the cations disorder but the anions do not. This disorder gives a temperature-dependent width to the electronic states in the conduction band. This width provides the anomalous Seebeck contribution.

  2. The Seebeck coefficient of superionic conductors

    SciTech Connect

    Mahan, G. D.

    2015-01-28

    We present a theory of the anomalous Seebeck coefficient found in the superionic conductor Cu{sub 2}Se. It has a phase transition at T = 400 K where the cations disorder but the anions do not. This disorder gives a temperature-dependent width to the electronic states in the conduction band. This width provides the anomalous Seebeck contribution.

  3. High-temperature superconducting conductors and cables

    SciTech Connect

    Peterson, D.E.; Maley, M.P.; Boulaevskii, L.; Willis, J.O.; Coulter, J.Y.; Ullmann, J.L.; Cho, Jin; Fleshler, S.

    1996-09-01

    This is the final report of a 3-year LDRD project at LANL. High-temperature superconductivity (HTS) promises more efficient and powerful electrical devices such as motors, generators, and power transmission cables; however this depends on developing HTS conductors that sustain high current densities J{sub c} in high magnetic fields at temperatures near liq. N2`s bp. Our early work concentrated on Cu oxides but at present, long wire and tape conductors can be best made from BSCCO compounds with high J{sub c} at low temperatures, but which are degraded severely at temperatures of interest. This problem is associated with thermally activated motion of magnetic flux lines in BSCCO. Reducing these dc losses at higher temperatures will require a high density of microscopic defects that will pin flux lines and inhibit their motion. Recently it was shown that optimum defects can be produced by small tracks formed by passage of energetic heavy ions. Such defects result when Bi is bombarded with high energy protons. The longer range of protons in matter suggests the possibility of application to tape conductors. AC losses are a major limitation in many applications of superconductivity such as power transmission. The improved pinning of flux lines reduces ac losses, but optimization also involves other factors. Measuring and characterizing these losses with respect to material parameters and conductor design is essential to successful development of ac devices.

  4. Critical switching impulse breakdown of long bundle-conductor gaps

    SciTech Connect

    Rizk, F.A.M.

    1996-01-01

    The paper presents a generalized physical approach to account for the effect of bundle geometry on critical switching impulse strength of long air gaps. The model covers phase-to-ground as well as phase-to-phase insulation. It has been applied to conventional symmetrical bundles as well as to more complex open configurations. The effect of bundle conductors was investigated for the following basic configurations: conductor-plane, conductor-rod, conductor-tower leg, conductor-tower window as well as phase-to-phase, within a wide range of clearances. The model is compared with previous analytical approaches as well as to extensive experimental results.

  5. Superconducting homopolar motor and conductor development

    NASA Astrophysics Data System (ADS)

    Gubser, Donald U.

    1996-10-01

    The U.S. Navy has been developing superconducting homopolar motors for ship applications since 1969; a successful at-sea demonstration of the first motor, using NbTi wire for the magnet, was achieved in the early 1980s. Recently, this same motor was used as a test bed to demonstrate progress in high-critical-temperature superconducting magnet technology using bismuth-strontium- calcium-copper-oxide (BSCCO) compounds. In the fall of 1995, this motor achieved a performance of 124 kW operating at a temperature of 4.2 K and 91 kW while operating at 28 K. Future tests are scheduled using new magnets with conductors of both the 2223 and the 2212 BSCCO phases. This article describes the advantages of superconducting propulsion and recent progress in the development of BSCCO conductors for use in Navy power systems.

  6. TOPICAL REVIEW: Disordering phenomena in superionic conductors

    NASA Astrophysics Data System (ADS)

    Keen, David A.

    2002-08-01

    Superionic conductors are materials which exhibit exceptionally high ionic conductivity whilst in the solid state. The manner in which certain structures accommodate superionic conduction has preoccupied many scientists throughout the latter part of the last century, beginning with the early debate about the disordered structure of the superionic α-phase of silver iodide. In this review, the key methods that have been used to deduce structural disorder in superionic conductors are described, and the important results summarized. The review focuses on simple archetypal systems, since these have dominated the literature, concentrating on more recent work and including emerging methodologies for deducing structural disorder. In most cases, the interpretation of diffuse scattering, as observed in scattering measurements, has played a crucial role in the understanding of these highly disordered systems and this is considered in some detail.

  7. Films of Carbon Nanomaterials for Transparent Conductors

    PubMed Central

    Ho, Xinning; Wei, Jun

    2013-01-01

    The demand for transparent conductors is expected to grow rapidly as electronic devices, such as touch screens, displays, solid state lighting and photovoltaics become ubiquitous in our lives. Doped metal oxides, especially indium tin oxide, are the commonly used materials for transparent conductors. As there are some drawbacks to this class of materials, exploration of alternative materials has been conducted. There is an interest in films of carbon nanomaterials such as, carbon nanotubes and graphene as they exhibit outstanding properties. This article reviews the synthesis and assembly of these films and their post-treatment. These processes determine the film performance and understanding of this platform will be useful for future work to improve the film performance. PMID:28809267

  8. Local noise in a diffusive conductor

    PubMed Central

    Tikhonov, E. S.; Shovkun, D. V.; Ercolani, D.; Rossella, F.; Rocci, M.; Sorba, L.; Roddaro, S.; Khrapai, V. S.

    2016-01-01

    The control and measurement of local non-equilibrium configurations is of utmost importance in applications on energy harvesting, thermoelectrics and heat management in nano-electronics. This challenging task can be achieved with the help of various local probes, prominent examples including superconducting or quantum dot based tunnel junctions, classical and quantum resistors, and Raman thermography. Beyond time-averaged properties, valuable information can also be gained from spontaneous fluctuations of current (noise). From these perspective, however, a fundamental constraint is set by current conservation, which makes noise a characteristic of the whole conductor, rather than some part of it. Here we demonstrate how to remove this obstacle and pick up a local noise temperature of a current biased diffusive conductor with the help of a miniature noise probe. This approach is virtually noninvasive for the electronic energy distributions and extends primary local measurements towards strongly non-equilibrium regimes. PMID:27466216

  9. Local noise in a diffusive conductor

    NASA Astrophysics Data System (ADS)

    Tikhonov, E. S.; Shovkun, D. V.; Ercolani, D.; Rossella, F.; Rocci, M.; Sorba, L.; Roddaro, S.; Khrapai, V. S.

    2016-07-01

    The control and measurement of local non-equilibrium configurations is of utmost importance in applications on energy harvesting, thermoelectrics and heat management in nano-electronics. This challenging task can be achieved with the help of various local probes, prominent examples including superconducting or quantum dot based tunnel junctions, classical and quantum resistors, and Raman thermography. Beyond time-averaged properties, valuable information can also be gained from spontaneous fluctuations of current (noise). From these perspective, however, a fundamental constraint is set by current conservation, which makes noise a characteristic of the whole conductor, rather than some part of it. Here we demonstrate how to remove this obstacle and pick up a local noise temperature of a current biased diffusive conductor with the help of a miniature noise probe. This approach is virtually noninvasive for the electronic energy distributions and extends primary local measurements towards strongly non-equilibrium regimes.

  10. Ionic conductors for solid oxide fuel cells

    DOEpatents

    Krumpelt, Michael; Bloom, Ira D.; Pullockaran, Jose D.; Myles, Kevin M.

    1993-01-01

    An electrolyte that operates at temperatures ranging from 600.degree. C. to 800.degree. C. is provided. The electrolyte conducts charge ionically as well as electronically. The ionic conductors include molecular framework structures having planes or channels large enough to transport oxides or hydrated protons and having net-positive or net-negative charges. Representative molecular framework structures include substituted aluminum phosphates, orthosilicates, silicoaluminates, cordierites, apatites, sodalites, and hollandites.

  11. Ionic conductors for solid oxide fuel cells

    SciTech Connect

    Krumpelt, M.; Bloom, I.D.; Pullockaran, J.D.; Myles, K.M.

    1991-12-31

    An electrolyte that operates at temperatures ranging from 600{degree}C to 800{degree}C is discussed. The electrolyte conducts charge ionically as well as electronically. The ionic conductors include molecular framework structures having planes or channels large enough to transport oxides or hydrated protons and having net-positive or net-negative charges. Representative molecular framework structures include substituted aluminum phosphates, orthosilicates, silicoaluminates, cordierites, apatites, sodalites, and hollandites.

  12. Cylindrical radial superlattice conductors for low loss microwave components

    NASA Astrophysics Data System (ADS)

    Rahimi, Arian; Wu, Jiyu; Cheng, Xiaoyu; Yoon, Yong-Kyu

    2015-03-01

    Theory and experimental demonstration of a cylindrical radial superlattice (CRS) conductor composed of alternating nanoscopic non-ferromagnetic/ferromagnetic metal layers are presented with focus on low conductor loss in a K-band microwave spectrum. The dynamic frequency response of the ferromagnetic thin films has been extracted using the Landau-Lifshitz-Gilbert equation which shows a negative magnetic permeability value in the frequencies above its ferromagnetic resonance. The reduction of the conductor loss results from the eddy current canceling (ECC) effect in the CRS conductors, where the negative-permeability ferromagnetic and positive-permeability non-ferromagnetic metal layers produce a zero effective permeability, resulting in virtually infinite skin depth at the targeted frequency. The closed and uniform boundary conditions inherent in the radial shape conductors preclude discontinuity effects occurring at the edges of the planar superlattice conductor and end up with a more effective ECC effect in practice. The design aspects with regards to the CRS materials and structural configuration are discussed. Simulations using a full-wave finite element method high frequency structure simulator are performed to show the ECC effect inside the CRS conductors. An air-lifted inductor made of the CRS conductor has been implemented to prove the effectiveness of the conductor loss reduction with the CRS conductor. The inductor shows an inductance value of 1-2 nH and a Q-factor of 45 at 18 GHz, which is the highest value reported at the frequency by now.

  13. Testing of the 3M Company Composite Conductor

    SciTech Connect

    Stovall, John P; Rizy, D Tom; Kisner, Roger A

    2010-10-01

    The 3M Company has developed a high-temperature low-sag conductor referred to as Aluminum-Conductor Composite-Reinforced or ACCR. The conductor uses an aluminum metal matrix material to replace the steel in conventional conductors. The objective of this work is to accelerate the commercial acceptance by electric utilities of this new conductor design by testing four representative conductor classes in controlled conditions. A unique facility called the Powerline Conductor Accelerated Testing (PCAT) Facility was built at ORNL for testing overhead conductors. The PCAT has been uniquely designed for testing overhead bare transmission line conductors at high currents and temperatures after they have been installed and tensioned to the manufacturer's specifications. The ability to operate a transmission line conductor in this manner does not exist elsewhere in the United States. Four classes of ACCR cable designed by the 3M Company have been successfully test at ORNL small, medium, large and small/compact. Based on these and other manufacturer tests, the 3M Company has successfully introduced the ACCR into the commercial market and has completed over twenty installations for utility companies.

  14. Multipole Expansion for a Single Helical Current Conductor

    NASA Astrophysics Data System (ADS)

    Tominaka, T.; Hatanaka, K.; Katayama, T.

    1997-05-01

    The purpose of this paper is to give the expression of the multipole expansion for a single helical current conductor. This analytical expression will be useful for the electromagnetic analysis of various helical coils such as helical dipoles, multifilamentary superconductors and superconducting strands. The present treatment of the multipole expansion for a single helical current conductor is derived as the extension of the case for a single straight current conductor. In addition, the comparison between the analytical and numerical calculations is presented for a single helical current conductor. As a result, the agreement between the analytical and numerical calculations is quite good, except the region near the radius of a single helical current conductor. Then, for the sum of the multipole expansion for a single helical current conductor, the Cesaro's method of summation are adopted.

  15. Accurate Simulations of Thermal Field of Operational Conductors

    NASA Astrophysics Data System (ADS)

    Xiao, Kai; Liu, Yongdou; Zhou, Huamin; Li, Weiquan; Li, Pengyun

    2017-09-01

    It is of significant importance to compute the exact thermal field of operational conductors so as to increase loading ampacity of operational transmission line in a safe manner. This paper performs an accurate thermal analysis for operational transmission conductors based on the two-dimensional steady-state heat transfer control functions. A refined finite element model for the section of conductor is used, which considers the main sources of heat gains, heat loss and studies the key factors affecting the radial temperature distribution. A typical aluminum conductor steel reinforced (ACSR) conductor is studied using the model presented herein, and the thermal distribution in its section is obtained. This paper discusses the effects of loading ampacity and convection condition on thermal field of conductors.

  16. Protection of Overhead Conductors at the Inlet to a Connector

    SciTech Connect

    Trofimov, S. V.

    2003-11-15

    A method that enables determination of maximum amplitudes of standing vibration waves, off-horizontal angles of the conductors, moments of resistance, and cutting forces in any cross section of any type of conductor and connector with the help of 'SVT-connector' software is described. Comparative values of the mentioned parameters at the outlet of the conductor from rigid dress and at the inlet to the connector are presented.

  17. 30 CFR 56.12048 - Communication conductors on power poles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Electricity § 56.12048 Communication conductors on power poles. Telegraph, telephone, or signal wires shall... powerlines, they shall be installed as specified by the National Electrical Code....

  18. Actuating dielectric elastomers in pure shear deformation by elastomeric conductors

    SciTech Connect

    Wang, Yin; Chen, Baohong; Zhou, Jinxiong; Bai, Yuanyuan; Wang, Hong

    2014-02-10

    Pure shear experiments are commonly used to characterize dielectric elastomer (DE) material properties and to evaluate DE actuator/generator performance. It is increasingly important for many applications to replace conventional carbon grease electrodes with stretchable elastomeric conductors. We formulate a theory for DE with elastomeric conductors, synthesize transparent hydrogel as ionic conductors, and measure actuation of DE in pure shear deformation. Maximum 67% actuation strain is demonstrated. The theory agrees well with our measurement and also correlates well with reported experiments on DE with electronic conductors.

  19. Flat conductor cable connectors with individually sealed contacts

    NASA Technical Reports Server (NTRS)

    Angele, W.

    1972-01-01

    Information is presented on flat conductor cable connectors, a series with individually sealed contacts. Data are concerned with connector historical development, design requirements, and testing and costs.

  20. Development of twisted high-temperature superconductor composite conductors

    SciTech Connect

    Christopherson, C.J.; Riley, G.N. Jr.

    1995-04-24

    Multifilamentary high-temperature superconductor (HTS) composite conductors have been developed for alternating current (ac) applications. A twisted HTS conductor containing the Bi-2223 phase fabricated using a modified powder-in-tube technique is reported. Transport critical current densities of 13 800 and 10 900 A/cm {sup 2} (77 K, self-field, 1 {mu}V/cm) have been achieved for twisted tape and wire conductors with twist pitches of 3.7 and 3.6 mm, respectively. These conductors are strongly linked and are thus suitable for use in ac applications.

  1. Development of twisted high-temperature superconductor composite conductors

    NASA Astrophysics Data System (ADS)

    Christopherson, C. J.; Riley, G. N., Jr.

    1995-04-01

    Multifilamentary high-temperature superconductor (HTS) composite conductors have been developed for alternating current (ac) applications. A twisted HTS conductor containing the Bi-2223 phase fabricated using a modified powder-in-tube technique is reported. Transport critical current densities of 13 800 and 10 900 A/cm 2 (77 K, self-field, 1 μV/cm) have been achieved for twisted tape and wire conductors with twist pitches of 3.7 and 3.6 mm, respectively. These conductors are strongly linked and are thus suitable for use in ac applications.

  2. Flat conductor cable for electrical packaging

    NASA Technical Reports Server (NTRS)

    Angele, W.

    1972-01-01

    Flat conductor cable (FCC) is relatively new, highly promising means for electrical packaging and system integration. FCC offers numerous desirable traits (weight, volume and cost savings, flexibility, high reliability, predictable and repeatable electrical characteristics) which make it extremely attractive as a packaging medium. FCC, today, finds wide application in everything from integration of lunar equipment to the packaging of electronics in nuclear submarines. Described are cable construction and means of termination, applicable specifications and standards, and total FCC systems. A list of additional sources of data is also included for more intensive study.

  3. NASA Test Conductor Monitoring DIME competition

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A NASA test conductor at the top of the 2.2-second Drop Tower monitors a student lecture at a lower level. This was part of the Microgravity Environment (DIME) competition held April 23-25, 2002, at NASA's Glenn Research Center. Competitors included two teams from Sycamore High School, Cincinnati, OH, and one each from Bay High School, Bay Village, OH, and COSI Academy, Columbus, OH. DIME is part of NASA's education and outreach activities. Details are on line at http://microgravity.grc.nasa.gov/DIME_2002.html.

  4. Noise and entanglement in quantum conductors

    SciTech Connect

    Lesovik, G. B.; Lebedev, A. V.

    2009-05-14

    In this article we discuss our two recent proposals on producing and detecting of entangled states in quantum conductors. First we analyze a setup where two electrons are scattered on a quantum dot with Coulomb repulsion and became orbitally entangled. Second, for identical noninteracting particles we suggest an operating scheme for the deliberate generation of spin-entangled electron pairs in a normal-metal mesoscopic structure with a fork geometry. The spin-entangled pair is created through a post-selection in the two branches of the fork. We also make comments on different ways of producing and quantifying the degree of entanglement.

  5. NASA Test Conductor Monitoring DIME competition

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A NASA test conductor at the top of the 2.2-second Drop Tower monitors a student lecture at a lower level. This was part of the Microgravity Environment (DIME) competition held April 23-25, 2002, at NASA's Glenn Research Center. Competitors included two teams from Sycamore High School, Cincinnati, OH, and one each from Bay High School, Bay Village, OH, and COSI Academy, Columbus, OH. DIME is part of NASA's education and outreach activities. Details are on line at http://microgravity.grc.nasa.gov/DIME_2002.html.

  6. Rubber Conductors for Aircraft Ignition Cables

    DTIC Science & Technology

    1945-11-01

    of Conduct~Rubber88mples and. II - Tests of’ Exper1mental Cables. The effect of diameter and resistivity of the cable oonductor on vol. tageJ the...detennipation of optimum oonduotc.r diameter for a short length at cable, and the effect of’ conductor diameter on dielectrio strength of’ the cable are...temperatUl~ o~ the strI~. The effect of successive stretches" eaoh of greater amplitude than the preceiling o:.:te" ia 6hown ::’’𔃺. f1b𔃻lI’e 2. The

  7. Miniaturized bendable 400 MHz artificial magnetic conductor

    NASA Astrophysics Data System (ADS)

    Presse, Anthony; Tarot, Anne-Claude

    2016-04-01

    A bendable artificial magnetic conductor (AMC) with a resonant frequency of 400 MHz is proposed. The dimensions of the unit cell are 50 × 50 mm2 or 0.07 × 0.07 λ0. The miniaturization is achieved with closely coupled patches printed on each side of a 0.127-mm-thick dielectric substrate. This last one is stacked on a flexible 3-mm-thick silicone over a ground plane. An AMC prototype is simulated and manufactured. Also, a printed inverted-F antenna is used to highlight the bandwidth of the AMC.

  8. Precision gold conductors for HMCs. Final report

    SciTech Connect

    Widmer, M.R.

    1994-08-01

    Ti/Pd/Au multiple code coded switch (MCCS) networks were built and compared to Cr/Au MCCS networks. The data showed no measurable difference between the two systems. Interface resistance of both types of networks was measured as a diagnostic aid to determine if hydrogen was affecting the Ti/Pd/Au MCCS networks. The data showed that although hydrogen does affect Ti/Pd/Au, the changes are not significant with respect to MCCS environments. An evaluation of several proprietary gold electroplating solutions for use in the production of Ti/Pd/Au conductors was performed. All the testing results were comparable to the current product requirements.

  9. 30 CFR 56.12010 - Isolation or insulation of communication conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... conductors. 56.12010 Section 56.12010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF... MINES Electricity § 56.12010 Isolation or insulation of communication conductors. Telephone and low... energized power conductors or any other power source....

  10. PREFACE: International Symposium on Molecular Conductors: Novel Functions of Molecular Conductors under Extreme Conditions (ISMC 2008)

    NASA Astrophysics Data System (ADS)

    Takahashi, Toshihiro; Suzumura, Yoshikazu

    2008-02-01

    The International Symposium on Molecular Conductors 2008 (ISMC2008) was held as the second international symposium of the project entitled `Novel Functions of Molecular Conductors under Extreme Conditions', which was supported by the Grant-in-aid for Scientific Research on Priority Areas from the Ministry of Education, Culture, Sports, Science and Technology in Japan. The project lasted from September 2003 to March 2008, and was completed by this symposium held at Okazaki Conference Center, Institute for Molecular Science, Okazaki, Japan (23-25 July 2008), which about 100 scientists attended. During the symposium, five project teams gave summary talks and exciting talks were given on the topics developed recently not only by the members of the project but also by other scientists including invited speakers from abroad, who are doing active research on molecular conductors. It is expected that papers presented in the symposium will give valuable hints for the next step in the research of this field. Therefore the organizers of this symposium decided to publish this proceedings in order to demonstrate these activities, not only for the local community of the project, but also for the broad society of international scientists who are interested in molecular conductors. The editors, who are also the organizers of this symposium, believe that this proceedings provides a significant and relevant contribution to the field of molecular conductors since it is the first time we have published such a proceedings as an electronic journal. We note that all papers published in this volume of Journal of Physics: Conference Series have been peer reviewed by expert referees. Editors made every effort to satisfy the criterion of a proceedings journal published by IOP Publishing. Toshihiro Takahashi and Yoshikazu Suzumura Editors: Toshihiro Takahashi (Gakushuin University) (Chairman) Kazushi Kanoda (University of Tokyo) Seiichi Kagoshima (University of Tokyo) Takehiko Mori (Tokyo

  11. Testing of the 3M Company ACCR Conductor

    SciTech Connect

    Stovall, J.P.; RIzy, D.T.; Kisner, R.A.; Deve, H.E.

    2010-09-15

    The 3M Company has developed a high-temperature low-sag conductor referred to as Aluminum- Conductor Composite-Reinforced or ACCR. The conductor uses an aluminum metal matrix material to replace the steel in conventional conductors so the core has a lower density and higher conductivity. The objective of this work is to accelerate the commercial acceptance by electric utilities of these new conductor designs by testing four representative conductor classes in controlled conditions. Overhead transmission lines use bare aluminum conductor strands wrapped around a steel core strands to transmit electricity. The typical cable is referred to as aluminum-conductor steel-reinforced (ACSR). The outer strands are aluminum, chosen for its conductivity, low weight, and low cost. The center strand is of steel for the strength required to support the weight without stretching the aluminum due to its ductility. The power density of a transmission corridor has been directly increased by increasing the voltage level. Transmission voltages have increased from 115-kV to 765- kV over the past 80 years. In the United States, further increasing the voltage level is not feasible at this point in time, so in order to further increase the power density of a transmission corridor, conductor designs that increase the current carrying capability have been examined. One of the key limiting factors in the design of a transmission line is the conductor sag which determines the clearance of the conductor above ground or underlying structures needed for electrical safety. Increasing the current carrying capability of a conductor increases the joule heating in the conductor which increases the conductor sag. A conductor designed for high-temperature and lowsag operation requires an engineered modification of the conductor materials. To make an advanced cable, the 3M Company solution has been the development of a composite conductor consisting of Nextel ceramic fibers to replace the steel core and

  12. Casimir interaction of arbitrarily shaped conductors.

    PubMed

    Straley, Joseph P; Kolomeisky, Eugene B

    2017-04-12

    We review a systematic practical implementation of the multiple scattering formalism due to Balian and Duplantier (1977 Ann. Phys. 104 300, 1978 Ann. Phys. 112 165) for the calculation of the Casimir interaction between arbitrarily shaped smooth conductors. The leading two-point scattering term of the expansion has a simple compact form, amenable to exact or accurate numerical evaluation. It is a general expression which improves upon the proximity force and pairwise summation approximations. We show that for many geometries it captures the bulk of the interaction effect. The inclusion of terms beyond the two-point approximation provides an accuracy check and explains screening. As an illustration of the power and versatility of the method we re-evaluate sphere-sphere and sphere-plane interactions and compared the results with previous findings that employed different methods. We also compute for the first time interaction of a hyperboloid (mimicking an atomic force microscope tip) and a plane. We also analyze the anomalous situations involving long cylindrical conductors where the two-point scattering approximation fails qualitatively. In such cases analytic summation of the entire scattering series is carried out and a topological argument is put forward as an explanation of the result. We give the extension of this theory to the case of finite temperatures where the two-point scattering approximation result has a simple compact form, also amenable to exact or accurate numerical evaluation.

  13. Novel processing of HTS based conductors

    NASA Astrophysics Data System (ADS)

    Ginley, D. S.; Venturini, E. L.; Kwak, J. F.; Baughman, R. J.; Bourcier, R. J.; Mitchell, M. A.; Morosin, B.; Halloran, J. W.; Neal, N. J.; Capone, D. W.

    1990-04-01

    Conductor development is one of the major long term goals in high temperature superconductor research. Two promising processing technologies that were utilized to produce superconducting HTS conductors are reported. First, melt spun YBa2Cu3O7 fibers rapid thermal processed for 1 to 8 sec at 950 to 1075 C have (Tc)'s to 92 K, J(sub c)'s to 1100 A/sq cm and the orthorhombic twinned morphology typical for high quality YBa2Cu3O7. A processing matrix of time, temperature and composition for these fibers shows that slightly CuO-rich starting compositions give the best results. Second, silver tube encapsulated wires of Bi(1.7)Pb(0.3)Sr2Ca2Cu3O10 were made by extrusion, wire drawing and cold rolling. The resulting tapes show orientation of the crystallites, zero resistance up to 100 K and improved magnetic hysteresis above 50 K. The combination of mechanical reprocessing and extended thermal anneals near 850 C appears to significantly improve these materials.

  14. Casimir interaction of arbitrarily shaped conductors

    NASA Astrophysics Data System (ADS)

    Straley, Joseph P.; Kolomeisky, Eugene B.

    2017-04-01

    We review a systematic practical implementation of the multiple scattering formalism due to Balian and Duplantier (1977 Ann. Phys. 104 300, 1978 Ann. Phys. 112 165) for the calculation of the Casimir interaction between arbitrarily shaped smooth conductors. The leading two-point scattering term of the expansion has a simple compact form, amenable to exact or accurate numerical evaluation. It is a general expression which improves upon the proximity force and pairwise summation approximations. We show that for many geometries it captures the bulk of the interaction effect. The inclusion of terms beyond the two-point approximation provides an accuracy check and explains screening. As an illustration of the power and versatility of the method we re-evaluate sphere–sphere and sphere–plane interactions and compared the results with previous findings that employed different methods. We also compute for the first time interaction of a hyperboloid (mimicking an atomic force microscope tip) and a plane. We also analyze the anomalous situations involving long cylindrical conductors where the two-point scattering approximation fails qualitatively. In such cases analytic summation of the entire scattering series is carried out and a topological argument is put forward as an explanation of the result. We give the extension of this theory to the case of finite temperatures where the two-point scattering approximation result has a simple compact form, also amenable to exact or accurate numerical evaluation.

  15. 46 CFR 111.60-4 - Minimum cable conductor size.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable...

  16. 46 CFR 111.60-4 - Minimum cable conductor size.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable...

  17. 46 CFR 111.60-4 - Minimum cable conductor size.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable...

  18. 46 CFR 111.60-4 - Minimum cable conductor size.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable...

  19. 46 CFR 111.60-4 - Minimum cable conductor size.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Minimum cable conductor size. 111.60-4 Section 111.60-4 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-4 Minimum cable conductor size. Each cable...

  20. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential electrical...

  1. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential electrical...

  2. 30 CFR 77.503 - Electric conductors; capacity and insulation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric conductors; capacity and insulation. 77.503 Section 77.503 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... UNDERGROUND COAL MINES Electrical Equipment-General § 77.503 Electric conductors; capacity and insulation...

  3. 30 CFR 77.503 - Electric conductors; capacity and insulation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electric conductors; capacity and insulation. 77.503 Section 77.503 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... UNDERGROUND COAL MINES Electrical Equipment-General § 77.503 Electric conductors; capacity and insulation...

  4. 30 CFR 77.503 - Electric conductors; capacity and insulation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electric conductors; capacity and insulation. 77.503 Section 77.503 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... UNDERGROUND COAL MINES Electrical Equipment-General § 77.503 Electric conductors; capacity and insulation...

  5. 30 CFR 77.503 - Electric conductors; capacity and insulation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric conductors; capacity and insulation. 77.503 Section 77.503 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... UNDERGROUND COAL MINES Electrical Equipment-General § 77.503 Electric conductors; capacity and insulation...

  6. 30 CFR 77.503 - Electric conductors; capacity and insulation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electric conductors; capacity and insulation. 77.503 Section 77.503 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... UNDERGROUND COAL MINES Electrical Equipment-General § 77.503 Electric conductors; capacity and insulation...

  7. The Identification of Conductor-Distinguished Functions of Conducting

    ERIC Educational Resources Information Center

    Gumm, Alan J.; Battersby, Sharyn L.; Simon, Kathryn L.; Shankles, Andrew E.

    2011-01-01

    The purpose of the present study was to identify whether conductors distinguish functions of conducting similarly to functions implied in previous research. A sample of 84 conductors with a full range of experience levels (M = 9.8) and of a full range of large ensemble types and ensemble age levels rated how much they pay attention to 82…

  8. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential...

  9. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential...

  10. 30 CFR 57.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false High-potential electrical conductors. 57.12011 Section 57.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Electricity Surface and Underground § 57.12011 High-potential electrical conductors. High-potential...

  11. Elastically stretchable thin film conductors on an elastomeric substrate

    NASA Astrophysics Data System (ADS)

    Jones Harris, Joyelle Elizabeth

    Imagine a large, flat screen television that can be rolled into a small cylinder after purchase in the store and then unrolled and mounted onto the wall of a home. The electronic devices within the television must be able to withstand large deformation and tensile strain. Consider a robot that is covered with an electronic skin that simulates human skin. The skin would enable the machine to lift an elderly person with care and sensitivity. The skin will endure repeated deformation with the highest tensile strains being experienced at the robot's joints. These applications and many others will benefit from stretchable electronic circuitry. While several different methods have been employed to create stretchable electronics, all methods use a common tool -- stretchable conductors. Therefore, the goal of this thesis work was to fabricate elastically stretchable conductors that can be used in stretchable electronics. We deposited Au thin films on an elastomeric substrate, and the resulting conductors remained electrically continuous when stretched by 30% and more. We developed photolithographic processes that can be used to pattern elastically stretchable conductors with a 10 mum resolution. We fabricated bi-level stretchable conductors that are separated by an elastomeric insulator and are electrically connected through via holes in the insulator. We applied our bi-level conductors to create a stretchable resistor-inductor-capacitor (RLC) circuit with a tunable resonant frequency. We also used stretchable conductors to measure action potentials in biological samples. This thesis describes the fabrication and application of our elastically stretchable conductors.

  12. 21 CFR 868.1920 - Esophageal stethoscope with electrical conductors.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Esophageal stethoscope with electrical conductors. 868.1920 Section 868.1920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... conductors is a device that is inserted into the esophagus to listen to a patient's heart and breath...

  13. 21 CFR 868.1920 - Esophageal stethoscope with electrical conductors.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Esophageal stethoscope with electrical conductors. 868.1920 Section 868.1920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... conductors is a device that is inserted into the esophagus to listen to a patient's heart and breath...

  14. 21 CFR 868.1920 - Esophageal stethoscope with electrical conductors.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Esophageal stethoscope with electrical conductors. 868.1920 Section 868.1920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... conductors is a device that is inserted into the esophagus to listen to a patient's heart and breath...

  15. 21 CFR 868.1920 - Esophageal stethoscope with electrical conductors.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Esophageal stethoscope with electrical conductors. 868.1920 Section 868.1920 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... conductors is a device that is inserted into the esophagus to listen to a patient's heart and breath...

  16. Professional Orchestral Conductors' Use of Selected Teaching Behaviors in Rehearsal

    ERIC Educational Resources Information Center

    Whitaker, Jennifer A.

    2017-01-01

    This descriptive study examined professional conductors' use of rehearsal time in sequential pattern components, discussing task presentation targets, and using verbal imagery and modeling techniques. Commercially available videos of 15 professional conductors rehearsing prominent orchestras were scripted, coded, and timed for selected teaching…

  17. Termination of flat conductor cable to NASA/MSFC plugs

    NASA Technical Reports Server (NTRS)

    Angele, W.

    1972-01-01

    Data, supplemented with artwork, are presented on the major steps involved with terminating flat conductor cable (FCC) to MSFC's FCC plugs. Cable and shield preparation steps include material cutting, insulation stripping, and plating of exposed conductors. Methods and equipment required to terminate FCC to each of four MSFC plugs are described.

  18. Effect of Conductor Expressivity on Ensemble Evaluations by Nonmusic Majors

    ERIC Educational Resources Information Center

    Price, Harry E.; Mann, Alison; Morrison, Steven J.

    2016-01-01

    This study continues research that examines effects that conductors have on the assessment of ensemble performances. The current study used the same four recordings orders of two strict and two expressive examples by two conductors with a single repeated recording used in previous research, but the participants were not music majors. In addition…

  19. The Effect of Conductor Expressivity on Ensemble Performance Evaluation

    ERIC Educational Resources Information Center

    Morrison, Steven J.; Price, Harry E.; Geiger, Carla G.; Cornacchio, Rachel A.

    2009-01-01

    In this study, the authors examined whether a conductor's use of high-expressivity or low-expressivity techniques affected evaluations of ensemble performances that were identical across conducting conditions. Two conductors each conducted two 1-minute parallel excerpts from Percy Grainger's "Walking Tune." Each directed one excerpt…

  20. [Disorders of adaptive processes in conductors of passenger cars].

    PubMed

    Kopirovskiĭ, K M; Delektorskiĭ, N V; Kutovoĭ, V S

    1998-01-01

    Passenger carriage conductors work under difficult conditions, including night working hours, unfavorable working and rest conditions with sleep impairment, and other poor factors. This makes it necessary to assume that the conductors should be given some advantages: privilege pension provision, shorter working travelling hours, longer intertrip rest and annual vacation, special nutrition, etc.

  1. 33 CFR 183.435 - Conductors in circuits of 50 volts or more.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... more. (c) This section does not apply to communication systems; electronic navigation equipment; resistance conductors that control circuit amperage; conductors in secondary circuits of ignition systems...

  2. 33 CFR 183.435 - Conductors in circuits of 50 volts or more.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... more. (c) This section does not apply to communication systems; electronic navigation equipment; resistance conductors that control circuit amperage; conductors in secondary circuits of ignition systems...

  3. Characterization of MgB2 Conductors for Coil Development

    NASA Astrophysics Data System (ADS)

    Aslanoglu, Z.; Arda, L.; Akin, Y.; Sumption, M. D.; Tomsic, M.; Hascicek, Y. S.

    2004-06-01

    The effects of the heat treatment conditions on microstructure and the transport critical current density of MgB2 wires, which were fabricated by the Continuous Tube Forming and Filling (CTFF) process, have been investigated. Two types of MgB2 conductors, Fe/MgB2 and Cu/MgB2, were studied. It was found that the sheath materials affect the optimum annealing profile of MgB2 conductor. The annealing temperature for Cu/MgB2 conductors was lower than that for the Fe/MgB2 conductors. The critical current density, Jc was measured to be 1.1×105 A/cm2 at 20 K in-self field for Cu/MgB2 conductor of 1.25 mm in diameter. The processing, microstructure and superconducting properties are presented.

  4. Effect of the magnetic material on AC losses in HTS conductors in AC magnetic field carrying AC transport current

    NASA Astrophysics Data System (ADS)

    Wan, Xing-Xing; Huang, Chen-Guang; Yong, Hua-Dong; Zhou, You-He

    2015-11-01

    This paper presents an investigation on the AC losses in several typical superconducting composite conductors using the H-formulation model. A single superconducting strip with ferromagnetic substrate or cores and a stack of coated conductors with ferromagnetic substrates are studied. We consider all the coated conductors carrying AC transport currents and simultaneously exposed to perpendicular AC magnetic fields. The influences of the amplitude, frequency, phase difference and ferromagnetic materials on the AC losses are investigated. The results show that the magnetization losses of single strip and stacked strips have similar characteristics. The ferromagnetic substrate can increase the magnetization loss at low magnetic field, and decrease the loss at high magnetic field. The ferromagnetic substrate can obviously increase the transport loss in stacked strips. The trends of total AC losses of single strip and stacked strips are similar when they are carrying current or exposed to a perpendicular magnetic field. The effect of the frequency on the total AC losses of single strip is related to the amplitude of magnetic field. The AC losses decrease with increasing frequency in low magnetic field region while increase in high magnetic field region. As the phase difference changes, there is a periodic variation for the AC losses. Moreover, when the strip is under only the transport current and magnetic field, the ferromagnetic cores will increase the AC losses for large transport current or field.

  5. Non-binding conductor load bearing roller for a gas-insulated transmission line having a corrugated outer conductor

    DOEpatents

    Fischer, William H.

    1984-01-01

    A gas-insulated transmission line includes a corrugated outer conductor, an inner conductor disposed within and insulated from the outer conductor by means of support insulators and an insulating gas, and a non-binding transport device for supporting and permitting movement of the inner conductor/insulating support assembly axially along the corrugated outer conductor without radial displacement and for moving without binding along corrugations of any slope less than vertical. The transport device includes two movable contacts, such as skids or rollers, supported on a common pivot lever, the pivot lever being rotatably disposed about a pivot lever axis, which pivot lever axis is in turn disposed on the periphery of a support insulator or particle trap if one is used. The movable contacts are separated axially a distance equal to the axial distance between the peaks and valleys of the corrugations of the outer conductor and separated radially a distance equal to the radial distance between the peaks and valleys of the corrugations of the outer conductor. The transport device has the pivot lever axis disposed parallel to the motion of travel of the inner conductor/insulating support assembly.

  6. Non-binding conductor load bearing roller for a gas-insulated transmission line having a corrugated outer conductor

    SciTech Connect

    Fischer, W.H.

    1984-04-24

    A gas-insulated transmission line includes a corrugated outer conductor, an inner conductor disposed within and insulated from the outer conductor by means of support insulators and an insulating gas, and a non-binding transport device for supporting and permitting movement of the inner conductor/insulating support assembly axially along the corrugated outer conductor without radial displacement and for moving without binding along corrugations of any slope less than vertical. The transport device includes two movable contacts, such as skids or rollers, supported on a common pivot lever, the pivot lever being rotatably disposed about a pivot lever axis, which pivot lever axis is in turn disposed on the periphery of a support insulator or particle trap if one is used. The movable contacts are separated axially a distance equal to the axial distance between the peaks and valleys of the corrugations of the outer conductor and separated radially a distance equal to the radial distance between the peaks and valleys of the corrugations of the outer conductor. The transport device has the pivot lever axis disposed parallel to the motion of travel of the inner conductor/insulating support assembly. 7 figs.

  7. Transparent conductive coatings

    NASA Technical Reports Server (NTRS)

    Ashok, S.

    1983-01-01

    Thin film transparent conductors are discussed. Materials with electrical conductivity and optical transparency are highly desirable in many optoelectronic applications including photovoltaics. Certain binary oxide semiconductors such as tin oxide (SnO2) and indium oxide (In2O3) offer much better performance tradeoff in optoelectronics as well as better mechanical and chemical stability than thin semitransparent films. These thin-film transparent conductors (TC) are essentially wide-bandgap degenerate semiconductors - invariably n-type - and hence are transparent to sub-bandgap (visible) radiation while affording high electrical conductivity due to the large free electron concentration. The principal performance characteristics of TC's are, of course, electrical conductivity and optical transmission. The TC's have a refractive index of around 2.0 and hence act as very efficient antireflection coatings. For using TC's in surface barrier solar cells, the photovoltaic barrier is of utmost importance and so the work function or electron affinity of the TC is also a very important material parameter. Fabrication processes are discussed.

  8. Proteins as solid-state electronic conductors.

    PubMed

    Ron, Izhar; Pecht, Israel; Sheves, Mordechai; Cahen, David

    2010-07-20

    Protein structures can facilitate long-range electron transfer in solution. But a fundamental question remains: can these structures also serve as solid-state electronic conductors? Answering this question requires methods for studying conductivity of the "dry" protein (which only contains tightly bound structured water molecules) sandwiched between two electronic conductors in a solid-state type configuration. If successful, such systems could serve as the basis for future, bioinspired electronic device technology. In this Account, we survey, analyze, and compare macroscopic and nanoscopic (scanning probe) solid-state conductivities of proteins, noting the inherent constraints of each of these, and provide the first status report on this research area. This analysis shows convincing evidence that "dry" proteins pass orders of magnitude higher currents than saturated molecules with comparable thickness and that proteins with known electrical activity show electronic conductivity, nearly comparable to that of conjugated molecules ("wires"). These findings suggest that the structural features of proteins must have elements that facilitate electronic conductivity, even if they do not have a known electron transfer function. As a result, proteins could serve not only as sensing, polar,or photoactive elements in devices (such as field-effect transistor configurations) but also as electronic conductors. Current knowledge of peptide synthesis and protein modification paves the way toward a greater understanding of how changes in a protein's structure affect its conductivity. Such an approach could minimize the need for biochemical cascades in systems such as enzyme-based circuits, which transduce the protein's response to electronic current. In addition, as precision and sensitivity of solid-state measurements increase, and as knowledge of the structure and function of "dry" proteins grows, electronic conductivity may become an additional approach to study electron

  9. Exploratory Development of Transparent Conductor Materials

    DTIC Science & Technology

    1975-03-01

    Zr DOPED Cd2 SnO4 FILMS 4 3. OPTICAL TRANSMNJSION OF SPRAY COATED CADMIUM STANNATE 14 -? ~ F ILM ,. DIFFUSE REFLECTANCE SPECTRA OF Cau2 SnOj and Cd2 Sn... properties by doping , 3. coating of different substrate materials and h. cadmium stannate film testing. S~Three deposition technologies have been...electrical and optical film properties by doping was attempted via partial cadmium or tin substitution to achieve larger band gaps, via substitutional

  10. Plasma waves and jets from moving conductors

    NASA Astrophysics Data System (ADS)

    Gralla, Samuel E.; Zimmerman, Peter

    2016-06-01

    We consider force-free plasma waves launched by the motion of conducting material through a magnetic field. We develop a spacetime-covariant formalism for perturbations of a uniform magnetic field and show how the transverse motion of a conducting fluid acts as a source. We show that fast-mode waves are sourced by the compressibility of the fluid, with incompressible fluids launching a pure-Alfvén outflow. Remarkably, this outflow can be written down in closed form for an arbitrary time-dependent, nonaxisymmetric incompressible flow. The instantaneous flow velocity is imprinted on the magnetic field and transmitted away at the speed of light, carrying detailed information about the conducting source at the time of emission. These results can be applied to transients in pulsar outflows and to jets from neutron stars orbiting in the magnetosphere of another compact object. We discuss jets from moving conductors in some detail.

  11. Plasmonics with two-dimensional conductors.

    PubMed

    Yoon, Hosang; Yeung, Kitty Y M; Kim, Philip; Ham, Donhee

    2014-03-28

    A wealth of effort in photonics has been dedicated to the study and engineering of surface plasmonic waves in the skin of three-dimensional bulk metals, owing largely to their trait of subwavelength confinement. Plasmonic waves in two-dimensional conductors, such as semiconductor heterojunction and graphene, contrast the surface plasmonic waves on bulk metals, as the former emerge at gigahertz to terahertz and infrared frequencies well below the photonics regime and can exhibit far stronger subwavelength confinement. This review elucidates the machinery behind the unique behaviours of the two-dimensional plasmonic waves and discusses how they can be engineered to create ultra-subwavelength plasmonic circuits and metamaterials for infrared and gigahertz to terahertz integrated electronics.

  12. Plasmonics with two-dimensional conductors

    PubMed Central

    Yoon, Hosang; Yeung, Kitty Y. M.; Kim, Philip; Ham, Donhee

    2014-01-01

    A wealth of effort in photonics has been dedicated to the study and engineering of surface plasmonic waves in the skin of three-dimensional bulk metals, owing largely to their trait of subwavelength confinement. Plasmonic waves in two-dimensional conductors, such as semiconductor heterojunction and graphene, contrast the surface plasmonic waves on bulk metals, as the former emerge at gigahertz to terahertz and infrared frequencies well below the photonics regime and can exhibit far stronger subwavelength confinement. This review elucidates the machinery behind the unique behaviours of the two-dimensional plasmonic waves and discusses how they can be engineered to create ultra-subwavelength plasmonic circuits and metamaterials for infrared and gigahertz to terahertz integrated electronics. PMID:24567472

  13. Giant inductance in non-ohmic conductor

    NASA Astrophysics Data System (ADS)

    Tanabe, Kenji; Taniguchi, Hiroki; Nakamura, Fumihiko; Terasaki, Ichiro

    2017-08-01

    An inductor is composed of a coil, and its design has seen little progress since its inception more than one hundred years ago. We propose a novel method of inducing inductance in a non-ohmic conductor. In this paper, we report a giant inductance of 42 H in Ca2RuO4 in the low frequency region at room temperature, as an example. The quality (Q) factor, defined as the ratio between the imaginary and real parts of impedance, approaches infinity in the static limit. Our inductor, therefore, displays ideal characteristics such as a large inductance and high Q factor, and it may be a prime candidate for next-generation inductors.

  14. Plasma bullets behavior in a tube covered by a conductor

    SciTech Connect

    Xian, Y. B.; Xu, H. T.; Lu, X. P. Pei, X. K.; Gong, W. W.; Lu, Y.; Liu, D. W.; Yang, Y.

    2015-06-15

    In this work, for better applications of atmospheric pressure plasma jets, the physics of plasma streamers in a glass tube with a part of it covered by a conductor is investigated. To better understand the propagation mechanism of plasma bullets in capillary tubes passing through a curved or narrow passage for some biomedical or material applications, the propagation of plasma streamers in a tube covered by a floating conductor is investigated. For a plasma streamer propagating in a tube covered by a conductor, the plasma streamer is suppressed and becomes shorter, and a secondary streamer is generated in the tube at the downstream end of the conductor. The larger the area covered by the conductor, or the thinner the tube, the stronger the plasma streamer is inhibited. The electric potential of the conductor is measured to be as high as 6 kV. On the other hand, a higher voltage applied on the HV electrode, or a higher gas flow rate will make the secondary plasma streamer longer. It is found that the capacitor formed by the conductor outside the tube and the wall of the tube plays an important role in inhibiting the original plasma streamer and generating the secondary streamer. Moreover, the active species generated by the original plasma play important role in generating a secondary plasma streamer.

  15. Plasma bullets behavior in a tube covered by a conductor

    NASA Astrophysics Data System (ADS)

    Xian, Y. B.; Xu, H. T.; Lu, X. P.; Pei, X. K.; Gong, W. W.; Lu, Y.; Liu, D. W.; Yang, Y.

    2015-06-01

    In this work, for better applications of atmospheric pressure plasma jets, the physics of plasma streamers in a glass tube with a part of it covered by a conductor is investigated. To better understand the propagation mechanism of plasma bullets in capillary tubes passing through a curved or narrow passage for some biomedical or material applications, the propagation of plasma streamers in a tube covered by a floating conductor is investigated. For a plasma streamer propagating in a tube covered by a conductor, the plasma streamer is suppressed and becomes shorter, and a secondary streamer is generated in the tube at the downstream end of the conductor. The larger the area covered by the conductor, or the thinner the tube, the stronger the plasma streamer is inhibited. The electric potential of the conductor is measured to be as high as 6 kV. On the other hand, a higher voltage applied on the HV electrode, or a higher gas flow rate will make the secondary plasma streamer longer. It is found that the capacitor formed by the conductor outside the tube and the wall of the tube plays an important role in inhibiting the original plasma streamer and generating the secondary streamer. Moreover, the active species generated by the original plasma play important role in generating a secondary plasma streamer.

  16. Flexible transparent conductors based on metal nanowire networks

    DOE PAGES

    Guo, Chuan Fei; Ren, Zhifeng

    2015-04-01

    Few conductors are transparent and flexible. Metals have the best electrical conductivity, but they are opaque and stiff in bulk form. However, metals can be transparent and flexible when they are very thin or properly arranged on the nanoscale. This review focuses on the flexible transparent conductors based on percolating networks of metal. Specifically, we discuss the fabrication, the means to improve the electrical conductivity, the large stretchability and its mechanism, and the applications of these metal networks. We also suggest some criteria for evaluating flexible transparent conductors and propose some new research directions in this emerging field.

  17. Batch fabrication process development for ferrite logic conductors

    NASA Technical Reports Server (NTRS)

    Heckler, C. H., Jr.; Bhiwandker, N. C.

    1972-01-01

    A process for fabricating ultrareliable magnetic ferrite logic circuits is described in which the conductors are formed by a combination of two batch type processes - photolithography and electroplating - and a mechanized writing process for completing conductors in the third dimension. Up to 4 turns, through an aperture 1 mm in diameter, are formed by the described process. The number of joints in the conductors is reduced by use of this process to only those which are required for input, output and power connections of a logic block. To demonstrate feasibility, 8-stage magnetic ring counter circuits have been fabricated.

  18. Insulation failure and externalized conductor of a single-coil Kentrox lead: an ongoing story?

    PubMed

    Bogossian, Harilaos; Mijic, Dejan; Frommeyer, Gerrit; Winter, Joachim

    2015-02-01

    Conductor externalization is a frequent complication with the St. Jude Medical Riata lead. Single case reports also reported externalization of conductors for dual-coil Biotronik leads. Up to now, conductor externalization has not yet been reported for any single coil leads. We report for the first time an externalization of conductors in a Biotronik Kentrox single-coil implantable cardioverter defibrillator (ICD) lead.

  19. 30 CFR 56.12005 - Protection of power conductors from mobile equipment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Protection of power conductors from mobile... MINES Electricity § 56.12005 Protection of power conductors from mobile equipment. Mobile equipment shall not run over power conductors, nor shall loads be dragged over power conductors, unless...

  20. 33 CFR 183.435 - Conductors in circuits of 50 volts or more.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Conductors in circuits of 50... Requirements § 183.435 Conductors in circuits of 50 volts or more. (a) Each conductor in a circuit that has a... nominal circuit voltage of each of three or more current carrying conductors in a duct, bundle, or cable...

  1. 33 CFR 183.435 - Conductors in circuits of 50 volts or more.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Conductors in circuits of 50... Requirements § 183.435 Conductors in circuits of 50 volts or more. (a) Each conductor in a circuit that has a... nominal circuit voltage of each of three or more current carrying conductors in a duct, bundle, or cable...

  2. 30 CFR 57.12048 - Communication conductors on power poles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., telephone, or signal wires shall not be installed on the same crossarm with power conductors. When carried on poles supporting powerlines, they shall be installed as specified by the National Electrical Code....

  3. Surface-mounted flat conductor cable for home wiring

    NASA Technical Reports Server (NTRS)

    Hankins, J. D.; Carden, J. R.

    1974-01-01

    The concepts are discussed which are being considered and developed for surface-mounted wiring using flat conductor cable. Safety aspects, problems being encountered, and advantages are also discussed.

  4. 46 CFR 120.372 - Equipment and conductor grounding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... INSTALLATION Power Sources and Distribution Systems § 120.372 Equipment and conductor grounding. (a) All... secondary windings of instrument transformers must be grounded. (b) On a nonmetallic vessel, where a...

  5. Origin of fast ion diffusion in super-ionic conductors

    PubMed Central

    He, Xingfeng; Zhu, Yizhou; Mo, Yifei

    2017-01-01

    Super-ionic conductor materials have great potential to enable novel technologies in energy storage and conversion. However, it is not yet understood why only a few materials can deliver exceptionally higher ionic conductivity than typical solids or how one can design fast ion conductors following simple principles. Using ab initio modelling, here we show that fast diffusion in super-ionic conductors does not occur through isolated ion hopping as is typical in solids, but instead proceeds through concerted migrations of multiple ions with low energy barriers. Furthermore, we elucidate that the low energy barriers of the concerted ionic diffusion are a result of unique mobile ion configurations and strong mobile ion interactions in super-ionic conductors. Our results provide a general framework and universal strategy to design solid materials with fast ionic diffusion. PMID:28635958

  6. A microstructure continuum approach to electromagneto-elastic conductors

    NASA Astrophysics Data System (ADS)

    Romeo, Maurizio

    2016-11-01

    A micromorphic continuum model of a deformable electromagnetic conductor is established introducing microdensities of bound and free charges. The conductive part of electric current consists of contributions due to free charges and microdeformation. Beside the conservation of charge, we derive suitable evolution equations for electric multipoles which are exploited to obtain the macroscopic form of Maxwell's equations. A constitutive model for electromagneto-elastic conductors is considered which allows for a natural characterization of perfect conductors independently on the form of the constitutive equation for the conduction current. A generalized Ohm's law is also derived for not ideal conductors which accounts for relaxation effects. The consequences of the linearized Ohm's law on the classic magnetic transport equation are shown.

  7. 42. VIEW TO SOUTHEAST; MBE BUILDING, THIRD FLOOR, CONDUCTORS' LOCKER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. VIEW TO SOUTHEAST; MBE BUILDING, THIRD FLOOR, CONDUCTORS' LOCKER ROOM INTERIOR (Dobson) - Los Angeles Union Passenger Terminal, Mail, Baggage, & Express Building, 800 North Alameda Street, Los Angeles, Los Angeles County, CA

  8. Instability of Dielectrics and Conductors in Electrostatic Fields

    NASA Astrophysics Data System (ADS)

    Allaire, Grégoire; Rauch, Jeffrey

    2017-04-01

    This article proves most of the assertion in §116 of Maxwell's treatise on electromagnetism. The results go under the name Earnshaw's Theorem and assert the absence of stable equilibrium configurations of conductors and dielectrics in an external electrostatic field.

  9. High voltage switches having one or more floating conductor layers

    SciTech Connect

    Werne, Roger W.; Sampayan, Stephen; Harris, John Richardson

    2015-11-24

    This patent document discloses high voltage switches that include one or more electrically floating conductor layers that are isolated from one another in the dielectric medium between the top and bottom switch electrodes. The presence of the one or more electrically floating conductor layers between the top and bottom switch electrodes allow the dielectric medium between the top and bottom switch electrodes to exhibit a higher breakdown voltage than the breakdown voltage when the one or more electrically floating conductor layers are not present between the top and bottom switch electrodes. This increased breakdown voltage in the presence of one or more electrically floating conductor layers in a dielectric medium enables the switch to supply a higher voltage for various high voltage circuits and electric systems.

  10. 46 CFR 120.372 - Equipment and conductor grounding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... INSTALLATION Power Sources and Distribution Systems § 120.372 Equipment and conductor grounding. (a) All... secondary windings of instrument transformers must be grounded. (b) On a nonmetallic vessel, where a...

  11. Origin of fast ion diffusion in super-ionic conductors

    NASA Astrophysics Data System (ADS)

    He, Xingfeng; Zhu, Yizhou; Mo, Yifei

    2017-06-01

    Super-ionic conductor materials have great potential to enable novel technologies in energy storage and conversion. However, it is not yet understood why only a few materials can deliver exceptionally higher ionic conductivity than typical solids or how one can design fast ion conductors following simple principles. Using ab initio modelling, here we show that fast diffusion in super-ionic conductors does not occur through isolated ion hopping as is typical in solids, but instead proceeds through concerted migrations of multiple ions with low energy barriers. Furthermore, we elucidate that the low energy barriers of the concerted ionic diffusion are a result of unique mobile ion configurations and strong mobile ion interactions in super-ionic conductors. Our results provide a general framework and universal strategy to design solid materials with fast ionic diffusion.

  12. Contact-spring forming machine for flat conductor cable receptacles

    NASA Technical Reports Server (NTRS)

    Angele, W.; Martineck, H. G.

    1968-01-01

    Machine tool produces beryllium-copper contact springs for FCC /flat conductor cable/ feed-through receptacles. The springs are heat-treated and plated to impart the required electrical contact properties.

  13. Design, development, fabrication and testing of high temperature Flat Conductor Cable (FCC)

    NASA Technical Reports Server (NTRS)

    Rigling, W. S.

    1974-01-01

    The results are presented of a development program for a flat, 25-conductor signal cable and a flat, 3-conductor power cable. Flat cables employ conductors made of strips or flattened round copper conductors insulated with polyimide films. It is shown that conductor thickness ranges from 0.003 to 0.010 inch, and begins to soften and loose mechanical strength at temperatures above 200 C.

  14. Magnetic flux-load current interactions in ferrous conductors

    NASA Astrophysics Data System (ADS)

    Cannell, Michael J.; McConnell, Richard A.

    1992-06-01

    A modeling technique has been developed to account for interactions between load current and magnetic flux in an iron conductor. Such a conductor would be used in the active region of a normally conducting homopolar machine. This approach has been experimentally verified and its application to a real machine demonstrated. Additionally, measurements of the resistivity of steel under the combined effects of magnetic field and current have been conducted.

  15. The magnetic field due to a number of toroidal conductors

    NASA Astrophysics Data System (ADS)

    Caldwell, J.

    1982-03-01

    This is an extension of the work carried out by Gibson and Caldwell on the optimization of the uniformity of the magnetic field produced in the bore of a toroidal conductor of rectangular cross section. In this paper the work is extended to consider the magnetic field due to a number of conductors. The usefulness of the work is assessed by comparing it to the work of Garrett, and numerical results are given for particular coil parameters.

  16. Tilt stability of rotating current rings with passive conductors

    SciTech Connect

    Zweibel, E.G.; Pomphrey, N.

    1984-12-01

    We study the combined effects of rotation and resistive passive conductors on the stability of a rigid current in an external magnetic field. We present numerical and approximate analytical solutions to the equations of motion, which show that the ring is always tilt unstable on the resistive decay timescale of the conductors, although rotation and eddy currents may stabilize it over short times. Possible applications of our model include spheromaks which rotate or which are encircled by energetic particle rings.

  17. 46 CFR 111.05-31 - Grounding conductors for systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... of: (1) The largest conductor supplying the system; or (2) No. 8 AWG (8.4mm2). (b) A conductor for... equivalent for parallel generators—AWG-MCM (mm2) Greater than Less than or equal to Size of the system grounding conductor—AWG(mm2) 2 (33.6) 8 (8.4) 2 (33.6) 0 (53.5) 6 (13.3) 0 (53.5) 3/0 (85.0) 4 (21.2)...

  18. 46 CFR 111.05-31 - Grounding conductors for systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... of: (1) The largest conductor supplying the system; or (2) No. 8 AWG (8.4mm2). (b) A conductor for... equivalent for parallel generators—AWG-MCM (mm2) Greater than Less than or equal to Size of the system grounding conductor—AWG(mm2) 2 (33.6) 8 (8.4) 2 (33.6) 0 (53.5) 6 (13.3) 0 (53.5) 3/0 (85.0) 4 (21.2)...

  19. 46 CFR 111.05-31 - Grounding conductors for systems.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... of: (1) The largest conductor supplying the system; or (2) No. 8 AWG (8.4mm2). (b) A conductor for... equivalent for parallel generators—AWG-MCM (mm2) Greater than Less than or equal to Size of the system grounding conductor—AWG(mm2) 2 (33.6) 8 (8.4) 2 (33.6) 0 (53.5) 6 (13.3) 0 (53.5) 3/0 (85.0) 4 (21.2)...

  20. 46 CFR 111.05-31 - Grounding conductors for systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... of: (1) The largest conductor supplying the system; or (2) No. 8 AWG (8.4mm2). (b) A conductor for... equivalent for parallel generators—AWG-MCM (mm2) Greater than Less than or equal to Size of the system grounding conductor—AWG(mm2) 2 (33.6) 8 (8.4) 2 (33.6) 0 (53.5) 6 (13.3) 0 (53.5) 3/0 (85.0) 4 (21.2)...

  1. 46 CFR 111.05-31 - Grounding conductors for systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... of: (1) The largest conductor supplying the system; or (2) No. 8 AWG (8.4mm2). (b) A conductor for... equivalent for parallel generators—AWG-MCM (mm2) Greater than Less than or equal to Size of the system grounding conductor—AWG(mm2) 2 (33.6) 8 (8.4) 2 (33.6) 0 (53.5) 6 (13.3) 0 (53.5) 3/0 (85.0) 4 (21.2)...

  2. New resistivity for high-mobility quantum Hall conductors

    NASA Technical Reports Server (NTRS)

    Mceuen, P. L.; Szafer, A.; Richter, C. A.; Alphenaar, B. W.; Jain, J. K.

    1990-01-01

    Measurements showing dramatic nonlocal behavior in the four-terminal resistances of a high-mobility quantum Hall conductor are presented. These measurements illustrate that the standard definition of the resistivity tensor is inappropriate, but they are in excellent agreement with a new model of the conductor that treats the edge and bulk conducting pathways independently. This model uses a single intensive parameter, analogous to a local resistivity for the bulk channel only, to characterize the system.

  3. Assembly of conductor guides for off-shore drilling platform

    SciTech Connect

    Campo, J. J.

    1985-12-31

    A conductor guide assembly for conductors of an off-shore well platform having a jacket with an interior pile for extending from a sea bed to above a water level which is over the sea bed. In accordance with one inventive feature, a first guide mechanism comprising a plurality of vertically spaced supports which hold the tubular conduits within the interior pile is assembled in a plurality of sections wherein the upper support of each section is provided with removable bolt-on units for supporting the first guide mechanism as successive sections are jointed thereto. In accordance with another inventive feature, a second guide mechanism comprises a pair of circular plates positioned to rotate within a lower deck opening and which are connected together and define a plurality of passages for receiving the plurality of conductors that extend in the interior pile. The connected plates are temporarily attached to the lower deck for transport so that the second guide mechanism can be detached and rotated to align the passages with the intended positions for the conductors whereafter the second guide mechanism is permanently attached to the lower deck. In accordance with another inventive feature, a third guide mechanism comprising a plurality of radially extending beams is supported on an upper deck. The second guide mechanism also has passages for access to the conductors and it too can be rotated into a position of alignment with the conductors and thereafter permanently fixed to the upper deck.

  4. Search for solid conductors of Na/+/ and K/+/ ions - Five new conductors

    NASA Technical Reports Server (NTRS)

    Singer, J.; Kautz, H.; Fielder, W.; Fordyce, J.

    1975-01-01

    Five new conductors of positive Na and K ions, for use as separators in high energy secondary batteries, have been discovered. They include: (1) the pyrochlores NaTaWO6 and NaTa2O5F; (2) the bcc form of NaSbO3; and (3) the niobates 2Na2O-3Nb2O5 and 2K2O-3Nb2O5, with the alkali ions probably in open layers of the completely determined structure. On the basis of approximately 40 structure types, generalizations have been made regarding the relation between structure and ionic transport.

  5. Spirally Structured Conductive Composites for Highly Stretchable, Robust Conductors and Sensors.

    PubMed

    Wu, Xiaodong; Han, Yangyang; Zhang, Xinxing; Lu, Canhui

    2017-07-12

    Flexible and stretchable electronics are highly desirable for next generation devices. However, stretchability and conductivity are fundamentally difficult to combine for conventional conductive composites, which restricts their widespread applications especially as stretchable electronics. Here, we innovatively develop a new class of highly stretchable and robust conductive composites via a simple and scalable structural approach. Briefly, carbon nanotubes are spray-coated onto a self-adhesive rubber film, followed by rolling up the film completely to create a spirally layered structure within the composites. This unique spirally layered structure breaks the typical trade-off between stretchability and conductivity of traditional conductive composites and, more importantly, restrains the generation and propagation of mechanical microcracks in the conductive layer under strain. Benefiting from such structure-induced advantages, the spirally layered composites exhibit high stretchability and flexibility, good conductive stability, and excellent robustness, enabling the composites to serve as highly stretchable conductors (up to 300% strain), versatile sensors for monitoring both subtle and large human activities, and functional threads for wearable electronics. This novel and efficient methodology provides a new design philosophy for manufacturing not only stretchable conductors and sensors but also other stretchable electronics, such as transistors, generators, artificial muscles, etc.

  6. A new cable-in-conduit conductor magnet with insulated strands

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Satarou; Yamamoto, Junya; Motojima, Osamu

    1995-09-01

    Many studies have used cable-in-conduit conductor (CICC) coils in trying to develop an AC superconducting magnet because of its enormous potential if AC losses were low and insulation voltage was high. The strands in the most recent CICC magnets are coated with chromium or another metal with high electrical resistance to order to induce current re-distribution among the strands and to avoid a quench caused by a current imbalance. Current re-distribution is highly complex and very difficult to analyze because the conditions of the strand surfaces and the contact areas vary greatly with the operation of the conductor. If, however, the cable currents were well-balanced, insulating the strands would be the best way to reduce AC losses. We propose a new CICC magnet structure featuring a current lead that balances the strand currents via its resistance. Having calculated current balances, we find that strand currents are well within the present parameters for nuclear fusion experiments and superconducting magnet energy storages.

  7. Conductor gestures influence evaluations of ensemble performance

    PubMed Central

    Morrison, Steven J.; Price, Harry E.; Smedley, Eric M.; Meals, Cory D.

    2014-01-01

    Previous research has found that listener evaluations of ensemble performances vary depending on the expressivity of the conductor’s gestures, even when performances are otherwise identical. It was the purpose of the present study to test whether this effect of visual information was evident in the evaluation of specific aspects of ensemble performance: articulation and dynamics. We constructed a set of 32 music performances that combined auditory and visual information and were designed to feature a high degree of contrast along one of two target characteristics: articulation and dynamics. We paired each of four music excerpts recorded by a chamber ensemble in both a high- and low-contrast condition with video of four conductors demonstrating high- and low-contrast gesture specifically appropriate to either articulation or dynamics. Using one of two equivalent test forms, college music majors and non-majors (N = 285) viewed sixteen 30 s performances and evaluated the quality of the ensemble’s articulation, dynamics, technique, and tempo along with overall expressivity. Results showed significantly higher evaluations for performances featuring high rather than low conducting expressivity regardless of the ensemble’s performance quality. Evaluations for both articulation and dynamics were strongly and positively correlated with evaluations of overall ensemble expressivity. PMID:25104944

  8. SYNTHESIS AND CHARACTERIZATION OF PROTON CONDUCTORS

    SciTech Connect

    Brinkman, K.

    2010-02-18

    The morphological and electrical properties of yttrium (Y) and indium (In) doped barium cerate perovskites of the form BaIn{sub 0.3-x}Y{sub x}Ce{sub 0.7}O{sub 3-{delta}} (with x=0-0.3) prepared by a modified Pechini method were investigated as potential high temperature proton conductors with improved chemical stability. The sinterability increased with the increase of In-doping, and the perovskite phase was found in the BaIn{sub 0.3-x}Y{sub x}Ce{sub 0.7}O{sub 3-{delta}} solid solutions over the range 0 {le} x {le} 0.3. The conductivities decreased (from x to x, insert quantitative values) while the tolerance to wet CO{sub 2} improved for BaIn{sub 0.3-x}Y{sub x}Ce{sub 0.7}O{sub 3-{delta}} samples with an increase of In-doping.

  9. Local electron heating in nanoscopic conductors

    NASA Astrophysics Data System (ADS)

    D'Agosta, Roberto; Sai, Na; di Ventra, Massimiliano

    2007-03-01

    The electron current density in nanoscale junctions is typically several orders of magnitude larger than the corresponding one in bulk electrodes. Consequently, the electron-electron scattering rate increases substantially in the junction. This leads to local electron heating of the underlying Fermi sea [1] in analogy to the local ionic heating that is due to the increased electron-phonon scattering rates [2]. By using a novel hydrodynamic formulation of transport [3], we predict the bias dependence of local electron heating in quasi-ballistic nanoscale conductors [1], its effect on ionic heating [1], and the consequent observable changes in the inelastic conductance [4]. [1] R. D'Agosta, N. Sai and M. Di Ventra, accepted in Nano Letters (2006). [2] Y.-C. Chen, M. Zwolak, and M. Di Ventra, Nano Lett. 3, 1961 (2003); Nano Lett. 4, 1709 (2004); Nano Lett. 5, 621 (2005). M. J. Montgomery, T. N. Todorov, and A. P. Sutton, J. Phys. Cond. Matt. 14, 5377 (2002). [3] R. D'Agosta and M. Di Ventra, J. Phys. Cond. Matt. in press. [4] R. D'Agosta and M. Di Ventra, in preparation.

  10. COATED ALLOYS

    DOEpatents

    Harman, C.G.; O'Bannon, L.S.

    1958-07-15

    A coating is described for iron group metals and alloys, that is particularly suitable for use with nickel containing alloys. The coating is glassy in nature and consists of a mixture containing an alkali metal oxide, strontium oxide, and silicon oxide. When the glass coated nickel base metal is"fired'' at less than the melting point of the coating, it appears the nlckel diffuses into the vitreous coating, thus providing a closely adherent and protective cladding.

  11. Aluminide coatings

    DOEpatents

    Henager, Jr; Charles, H [Kennewick, WA; Shin, Yongsoon [Richland, WA; Samuels, William D [Richland, WA

    2009-08-18

    Disclosed herein are aluminide coatings. In one embodiment coatings are used as a barrier coating to protect a metal substrate, such as a steel or a superalloy, from various chemical environments, including oxidizing, reducing and/or sulfidizing conditions. In addition, the disclosed coatings can be used, for example, to prevent the substantial diffusion of various elements, such as chromium, at elevated service temperatures. Related methods for preparing protective coatings on metal substrates are also described.

  12. Application of mixed-organic-cation for high performance hole-conductor-free perovskite solar cells.

    PubMed

    Xiao, Meng; Zhao, Li; Wei, Shoubin; Li, Yanyan; Dong, Binghai; Xu, Zuxun; Wan, Li; Wang, Shimin

    2017-09-15

    ABX3-type organic lead halide perovskites have gained increasing attention as light harvester for solar cells due to their high power conversion efficiency (PCE). Recently, it has become a trend to avoid the use of expensive hole-transport materials (HTMs) and precious metals, such as Au, to be competitive in future commercial development. In this study, we fabricated mixed-cation perovskite-based solar cells through one-step spin-coating using methylammonium (CH3NH3(+)) and formamidinium (HN=CHNH3(+)) cations to extend the optical absorption range into the red region and enhance the utilization of solar light. The synthesized hole-conductor-free cells with carbon electrode and mixed cations exhibited increased short-circuit current, outperforming the cells prepared with pure methylammonium, and PCE of 10.55%. This paper proposes an efficient approach for fabricating high-performance and low-cost perovskite solar cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. A new cable-in-conduit conductor magnet with insulated strands

    NASA Astrophysics Data System (ADS)

    Yamaguchi, S.; Yamamoto, J.; Motojima, O.

    Many studies have used cable-in-conduit conductor (CICC) coils in trying to develop an a.c. superconducting magnet. The strands in the most recent CICC magnets are coated with chromium or another metal with high electrical resistance in order to induce current redistribution among the strands and to avoid a quench caused by a current imbalance. If, however, the cable currents were well balanced, insulating the strands would be the best way to reduce a.c. losses. We propose a new CICC magnet structure featuring a current lead that balances the strand current via its resistance. Having calculated current balances, we find that strand currents are well within the present parameters for nuclear fusion experiments and superconducting magnet energy storages.

  14. The load-carrying and thermal characteristics of flat conductor cable

    NASA Technical Reports Server (NTRS)

    Adams, G. D.

    1973-01-01

    The load-carrying and thermal characteristics of flat conductor cable and round wire cables have been investigated with all conductors in each cable under varying loads in air and vacuum environments. The test procedure is described and results are presented in graphic form. Derating factors for both round wire and flat conductor cable are established for operation in a vacuum environment. Rating factors are established for flat conductor cable for use with round wire loading tables. The results of these tests show that single layer flat conductor size, or that the voltage drop across flat conductor cable will be lower than that of round cable under the same load.

  15. Center conductor diagnostic for multipactor detection in inaccessible geometries.

    PubMed

    Chaplin, Vernon H; Hubble, Aimee A; Clements, Kathryn A; Graves, Timothy P

    2017-01-01

    Electron collecting current probes are the most reliable diagnostic of multipactor and radiofrequency (RF) ionization breakdown; however, stand-alone probes can only be used in test setups where the breakdown region is physically accessible. This paper describes techniques for measuring multipactor current directly on the center conductor of a coaxial RF device (or more generally, on the signal line in any two-conductor RF system) enabling global multipactor detection with improved sensitivity compared to other common diagnostics such as phase null, third harmonic, and reflected power. The center conductor diagnostic may be AC coupled for use in systems with a low DC impedance between the center conductor and ground. The effect of DC bias on the breakdown threshold was studied: in coaxial geometry, the change in threshold was <1 dB for positive biases satisfying VDC/VRF0<0.8, where VRF0 is the RF voltage amplitude at the unperturbed breakdown threshold. In parallel plate geometry, setting VDC/VRF0<0.2 was necessary to avoid altering the threshold by more than 1 dB. In most cases, the center conductor diagnostic functions effectively with no bias at all-this is the preferred implementation, but biases in the range VDC=0-10V may be applied if necessary. The polarity of the detected current signal may be positive or negative depending on whether there is net electron collection or emission globally.

  16. Center conductor diagnostic for multipactor detection in inaccessible geometries

    NASA Astrophysics Data System (ADS)

    Chaplin, Vernon H.; Hubble, Aimee A.; Clements, Kathryn A.; Graves, Timothy P.

    2017-01-01

    Electron collecting current probes are the most reliable diagnostic of multipactor and radiofrequency (RF) ionization breakdown; however, stand-alone probes can only be used in test setups where the breakdown region is physically accessible. This paper describes techniques for measuring multipactor current directly on the center conductor of a coaxial RF device (or more generally, on the signal line in any two-conductor RF system) enabling global multipactor detection with improved sensitivity compared to other common diagnostics such as phase null, third harmonic, and reflected power. The center conductor diagnostic may be AC coupled for use in systems with a low DC impedance between the center conductor and ground. The effect of DC bias on the breakdown threshold was studied: in coaxial geometry, the change in threshold was <1 dB for positive biases satisfying VD C/VR F 0 <0.8 , where VRF0 is the RF voltage amplitude at the unperturbed breakdown threshold. In parallel plate geometry, setting VD C/VR F 0 <0.2 was necessary to avoid altering the threshold by more than 1 dB. In most cases, the center conductor diagnostic functions effectively with no bias at all—this is the preferred implementation, but biases in the range VD C=0 -10 V may be applied if necessary. The polarity of the detected current signal may be positive or negative depending on whether there is net electron collection or emission globally.

  17. Use of ion conductors in the pyrochemical reduction of oxides

    DOEpatents

    Miller, W.E.; Tomczuk, Z.

    1994-02-01

    An electrochemical process and electrochemical cell for reducing a metal oxide are provided. First the oxide is separated as oxygen gas using, for example, a ZrO[sub 2] oxygen ion conductor anode and the metal ions from the reduction salt are reduced and deposited on an ion conductor cathode, for example, sodium ion reduced on a [beta]-alumina sodium ion conductor cathode. The generation of and separation of oxygen gas avoids the problem with chemical back reaction of oxygen with active metals in the cell. The method also is characterized by a sequence of two steps where an inert cathode electrode is inserted into the electrochemical cell in the second step and the metallic component in the ion conductor is then used as the anode to cause electrochemical reduction of the metal ions formed in the first step from the metal oxide where oxygen gas formed at the anode. The use of ion conductors serves to isolate the active components from chemically reacting with certain chemicals in the cell. While applicable to a variety of metal oxides, the invention has special importance for reducing CaO to Ca[sup o] used for reducing UO[sub 2] and PuO[sub 2] to U and Pu. 2 figures.

  18. Use of ion conductors in the pyrochemical reduction of oxides

    DOEpatents

    Miller, William E.; Tomczuk, Zygmunt

    1994-01-01

    An electrochemical process and electrochemical cell for reducing a metal oxide are provided. First the oxide is separated as oxygen gas using, for example, a ZrO.sub.2 oxygen ion conductor anode and the metal ions from the reduction salt are reduced and deposited on an ion conductor cathode, for example, sodium ion reduced on a .beta.-alumina sodium ion conductor cathode. The generation of and separation of oxygen gas avoids the problem with chemical back reaction of oxygen with active metals in the cell. The method also is characterized by a sequence of two steps where an inert cathode electrode is inserted into the electrochemical cell in the second step and the metallic component in the ion conductor is then used as the anode to cause electrochemical reduction of the metal ions formed in the first step from the metal oxide where oxygen gas formed at the anode. The use of ion conductors serves to isolate the active components from chemically reacting with certain chemicals in the cell. While applicable to a variety of metal oxides, the invention has special importance for reducing CaO to Ca.degree. used for reducing UO.sub.2 and PuO.sub.2 to U and Pu.

  19. Hearing status among Norwegian train drivers and train conductors

    PubMed Central

    2013-01-01

    Background There is a general perception that train drivers and conductors may be at increased risk of developing noise-induced hearing loss. Aims To study job-related hearing loss among train drivers and train conductors. Methods Audiograms from train drivers and train conductors were obtained from the medical records of the occupational health service of the major Norwegian railway company. The results were compared with audiograms from an internal control group of railway workers and an external reference group of people not occupationally exposed to noise. The monaural hearing threshold level at 4kHz, the mean binaural value at 3, 4 and 6kHz and the prevalence of audiometric notches (≥25 dB at 4kHz) were used for comparison. Results Audiograms were available for 1567 drivers, 1565 conductors, 4029 railway worker controls and 15 012 people not occupationally exposed to noise. No difference in hearing level or prevalence of audiometric notches was found between study groups after adjusting for age and gender. Conclusions Norwegian train drivers and conductors have normal hearing threshold levels comparable with those in non-exposed groups. PMID:24204021

  20. Hearing status among Norwegian train drivers and train conductors.

    PubMed

    Lie, A; Skogstad, M; Johnsen, T S; Engdahl, B; Tambs, K

    2013-12-01

    There is a general perception that train drivers and conductors may be at increased risk of developing noise-induced hearing loss. To study job-related hearing loss among train drivers and train conductors. Audiograms from train drivers and train conductors were obtained from the medical records of the occupational health service of the major Norwegian railway company. The results were compared with audiograms from an internal control group of railway workers and an external reference group of people not occupationally exposed to noise. The monaural hearing threshold level at 4kHz, the mean binaural value at 3, 4 and 6kHz and the prevalence of audiometric notches (≥25 dB at 4kHz) were used for comparison. Audiograms were available for 1567 drivers, 1565 conductors, 4029 railway worker controls and 15 012 people not occupationally exposed to noise. No difference in hearing level or prevalence of audiometric notches was found between study groups after adjusting for age and gender. Norwegian train drivers and conductors have normal hearing threshold levels comparable with those in non-exposed groups.

  1. Synergistic, ultrafast mass storage and removal in artificial mixed conductors

    NASA Astrophysics Data System (ADS)

    Chen, Chia-Chin; Fu, Lijun; Maier, Joachim

    2016-08-01

    Mixed conductors—single phases that conduct electronically and ionically—enable stoichiometric variations in a material and, therefore, mass storage and redistribution, for example, in battery electrodes. We have considered how such properties may be achieved synergistically in solid two-phase systems, forming artificial mixed conductors. Previously investigated composites suffered from poor kinetics and did not allow for a clear determination of such stoichiometric variations. Here we show, using electrochemical and chemical methods, that a melt-processed composite of the ‘super-ionic’ conductor RbAg4I5 and the electronic conductor graphite exhibits both a remarkable silver excess and a silver deficiency, similar to those found in single-phase mixed conductors, even though such behaviour is not possible in the individual phases. Furthermore, the kinetics of silver uptake and release is very fast. Evaluating the upper limit set by interfacial ambipolar diffusion reveals chemical diffusion coefficients that are even higher than those achieved for sodium chloride in bulk liquid water. These results could potentially stimulate systematic research into powerful, even mesoscopic, artificial mixed conductors.

  2. Search for solid conductors of Na(+) and K(+) ions: Five new conductors

    NASA Technical Reports Server (NTRS)

    Singer, J.; Kautz, H.; Fielder, W. L.; Fordyce, J.

    1975-01-01

    Five conductors of three structure types were discovered which, as solids, can transport Na(+) or K(+) ions with conductivities of approximately .00001/(omega cm) at 300 K. These compounds are: (1) the pyrochlores NaTaWO6 and NaTa2O5F, both with an activation energy for conduction delta E of 21 kJ/mole; (2) the bodycentered cubic form of NaSbO3, with delta E = 42 kJ/mole; and (3) the niobates 2Na2O with 3Nb2O5 and 2K2O with 3Nb2O5, with the alkali ions probably in open layers of the incompletely determined structure; delta E = 17 kJ/mole. On the basis of approximately 40 structure types, some generalizations were made regarding the relation between structure and ionic transport.

  3. Transport in low-dimensional conductors

    NASA Astrophysics Data System (ADS)

    Hruska, Marina Milan

    In this thesis, I address the problems of transport in low-dimensional conductors and superconductors. The problem of how the onset of superconductivity takes place in low-dimensional superconductors has been studied for a long time. Until recently, the zero-temperature phase transition in thin films was believed to occur from the superconducting to an insulating state. The question of existence of an intermediate metallic phase in a superconductor-metal-insulator transition is still an open experimental question. The effects that need to be addressed are those of superconducting quantum fluctuations and the weak-localization effects. In this dissertation I neglect the weak-localization corrections. I present a model which shows the existence of a zero-temperature superconductor-metal transition in thin films. The transition takes place even in the absence of disorder, and at an arbitrarily large normal-state film conductance. Mesoscopic superconducting fluctuations in superconducting junctions have been studied since the 1980's, but only recently has experimental evidence appeared with advances in fabrication of superconductor-ferromagnet-superconductor junctions. I studied the case of thick superconductor-metallic ferromagnet-superconductor junctions and present how even in this case, when the current averaged over the impurity distribution is exponentially small in the ferromagnetic-layer thickness, mesoscopic effects can cause the sample specific current to oscillate with temperature. The conductance of an electron gas at low temperatures is dominated by quantum, interference effects, whereas at high temperatures the scattering events can be considered independent of each other, so the Boltzmann kinetic equation governs the electron dynamics and the Drude result is obtained. In the intermediate region of temperatures, there appear classical corrections to transport coefficients that are due to correlations between individual scattering events. The effects of

  4. Quantum Optics Theory of Electronic Noise in Coherent Conductors.

    PubMed

    Grimsmo, Arne L; Qassemi, Farzad; Reulet, Bertrand; Blais, Alexandre

    2016-01-29

    We consider the electromagnetic field generated by a coherent conductor in which electron transport is described quantum mechanically. We obtain an input-output relation linking the quantum current in the conductor to the measured electromagnetic field. This allows us to compute the outcome of measurements on the field in terms of the statistical properties of the current. We moreover show how under ac bias the conductor acts as a tunable medium for the field, allowing for the generation of single- and two-mode squeezing through fermionic reservoir engineering. These results explain the recently observed squeezing using normal tunnel junctions [G. Gasse et al., Phys. Rev. Lett. 111, 136601 (2013); J.-C. Forgues et al., Phys. Rev. Lett. 114, 130403 (2015)].

  5. Mobility propagation and dynamic facilitation in superionic conductors

    SciTech Connect

    Annamareddy, Ajay Eapen, Jacob

    2015-11-21

    In an earlier work [V. A. Annamareddy et al., Phys. Rev. E 89, 010301(R) (2014)], we showed the manifestation of dynamical heterogeneity (DH)—the presence of clustered mobile and immobile regions—in UO{sub 2}, a model type II superionic conductor. In the current work, we demonstrate the mechanism of dynamic facilitation (DF) in two superionic conductors (CaF{sub 2} and UO{sub 2}) using atomistic simulations. Using the mobility transfer function, DF is shown to vary non-monotonically with temperature with the intensity of DF peaking at temperatures close to the superionic transition temperature (T{sub λ}). Both the metrics quantifying DH and DF show remarkable correspondence implying that DF, in the framework of kinematically constrained models, underpins the heterogeneous dynamics in type II superionic conductors.

  6. Transient finite element method using edge elements for moving conductor

    SciTech Connect

    Tani, Koji; Nishio, Takayuki; Yamada, Takashi ); Kawase, Yoshihiro . Dept. of Information Science)

    1999-05-01

    For the next generation of high speed railway systems and automobiles new braking systems are currently under development. These braking systems take into account the eddy currents, which are produced by the movement of the conductor in the magnetic field. For their optimum design, it is necessary to know the distribution of eddy currents in the moving conductor. The finite element method (FEM) is often used to simulate them. Here, transient finite element method using edge elements for moving conductor is presented. Here the magnetic vector potential is interpolated at the upwind position and the time derivative term is discretized by the backward difference method. As a result, the system matrix becomes symmetric and the ICCG method is applicable to solve the matrix. This method is used to solve an eddy current rail brake system. The results demonstrate that this approach is suitable to solve transient problems involving movement.

  7. Fundamental Physics and Promising Applications of Superionic Conductors

    NASA Astrophysics Data System (ADS)

    Yugami, Hiroo; Ishigame, Mareo

    1993-02-01

    Recently, superionic conductors (SIC’s) have been considered to be a key material for several application fields as well as energy engineering and ceramic technology. We review the recent stage of the basic models and concepts for the physical understanding of high-speed ionic transport in solids. In the latter part of this paper, we briefly review the applications of SIC’s to solid-state fuel cells and sensors. As a new application of SIC’s, we introduce a technique developed on a complex system consisting of an oxygen ionic conductor and high-Tc oxide super-conductors. Finally, we introduce the possibility of the application of SIC’s to optical devices.

  8. Metal Coatings

    NASA Technical Reports Server (NTRS)

    1994-01-01

    During the Apollo Program, General Magnaplate Corporation developed process techniques for bonding dry lubricant coatings to space metals. The coatings were not susceptible to outgassing and offered enhanced surface hardness and superior resistance to corrosion and wear. This development was necessary because conventional lubrication processes were inadequate for lightweight materials used in Apollo components. General Magnaplate built on the original technology and became a leader in development of high performance metallurgical surface enhancement coatings - "synergistic" coatings, - which are used in applications from pizza making to laser manufacture. Each of the coatings is designed to protect a specific metal or group of metals to solve problems encountered under operating conditions.

  9. A base-metal conductor system for silicon solar cells

    NASA Technical Reports Server (NTRS)

    Coleman, M. G.; Pryor, R. A.; Sparks, T. G.

    1980-01-01

    Solder, copper, and silver are evaluated as conductor layer metals for silicon solar cell metallization on the basis of metal price stability and reliability under operating conditions. Due to its properties and cost, copper becomes an attractive candidate for the conductor layer. It is shown that nickel operates as an excellent diffusion barrier between copper and silicon while simultaneously serving as an electrical contact and mechanical contact to silicon. The nickel-copper system may be applied to the silicon by plating techniques utilizing a variety of plating bath compositions. Solar cells having excellent current-voltage characteristics are fabricated to demonstrate the nickel-copper metallization system.

  10. Equivalent circuit of the barrier-conductor structures

    NASA Astrophysics Data System (ADS)

    Sinkkonen, J.

    Novel heterostructure devices are comprised of potential barriers connected by short conductors. In this paper we present a simple theory for the transport properties of the barrier-conductor chain. The analysis is based on the solution of the Boltzmann equation supplemented by the boundary conditions provided by the barrier reflection and transmission probabilities. As an application of the theory the small signal equivalent circuit is constructed for the single and double barrier cases and for the infinite periodic chain. The high frequency properties of these structures are discussed. In general, the multibarrier structures show transit time resonances associated with multiple reflections.

  11. Conductor design for the VLHC transmission line magnet

    SciTech Connect

    Foster, G.W.; Kashikhin, V.; McAshan, M.; Mazur, P.O.; Piekarz, H.; Volk, J.T.; Walker, R.

    1999-03-01

    The transmission line magnet [1] is under development for the Very Large Hadron Collider (VLHC) at Fermilab with the expectation that it’s cost will be several times less (per Tesla-meter) than conventional superconducting magnets. It is a dual-aperture warm-iron superferric magnet built around an 80kA superconducting transmission line. The superconductor consists of 8 Rutherford (SSC Outer) cables in an Invar pipe jacket. The conductor design requirements and development program is described. A 100kA conductor test facility based on inductive coupling is described.

  12. Scaling theory of phase-coherent metallic conductors

    NASA Astrophysics Data System (ADS)

    Macêdo, A. M.

    2002-07-01

    We present a scaling theory for describing the smooth crossover from ballistic to diffusive transport in phase-coherent metallic conductors. The theory confirms a recent conjecture by Beenakker [Rev. Mod. Phys. 69, 731 (1997)], and represents a substantial improvement in the two-terminal version of Nazarov's circuit theory [Phys. Rev. Lett. 73, 134 (1994); 73, 1420 (1994)]. In addition, our approach allows for the explicit inclusion of interfaces of arbitrary transparency, which are described using the supersymmetric nonlinear σ model. The problem of two identical barriers separated by a diffusive conductor is solved exactly, and expressions for both the normal and Andreev conductances are presented.

  13. Design of a Wireless Sensor Module for Monitoring Conductor Galloping of Transmission Lines

    PubMed Central

    Huang, Xinbo; Zhao, Long; Chen, Guimin

    2016-01-01

    Conductor galloping may cause flashovers and even tower collapses. The available conductor galloping monitoring methods often employ acceleration sensors to measure the conductor translations without considering the conductor twist. In this paper, a new sensor for monitoring conductor galloping of transmission lines based on an inertial measurement unit and wireless communication is proposed. An inertial measurement unit is used for collecting the accelerations and angular rates of a conductor, which are further transformed into the corresponding geographic coordinate frame using a quaternion transformation to reconstruct the galloping of the conductor. Both the hardware design and the software design are described in details. The corresponding test platforms are established, and the experiments show the feasibility and accuracy of the proposed monitoring sensor. The field operation of the proposed sensor in a conductor spanning 734 m also shows its effectiveness. PMID:27735852

  14. Technique for abrasive cutting of thick-film conductors for hybrid circuits

    NASA Technical Reports Server (NTRS)

    Nugent, J. B.; Palermo, J. S.

    1969-01-01

    Abrasive jet technique, producing prototype conductor networks for thick-film hybrid microcircuits, does not require screening and fixing procedures. Pantograph engraver is used to perform abrasive cutting of the conductor network.

  15. Degradation of a REBCO conductor due to an axial tensile stress under edgewise bending: a major stress mode of deterioration in a high field REBCO coil’s performance

    NASA Astrophysics Data System (ADS)

    Kajita, K.; Takao, T.; Maeda, H.; Yanagisawa, Y.

    2017-07-01

    The influence of an axial tensile stress under edgewise bending on the current transport property of a REBCO-coated conductor is described from the viewpoint of it being one of the major stress modes of degradation in a high field REBCO coil’s performance due to electromagnetic forces. A new type of a tensile experiment for the combination of an axial tensile stress, edgewise bending and flatwise bending on a REBCO conductor demonstrates that the combined stress increases tensile strain at the outer edge of the conductor and generates mechanical cracks in the superconducting layer, which causes an earlier degradation than a pure tensile stress. This combined stress mode can cause degradation of a high field REBCO coil’s performance below an operating hoop stress and countermeasures need to be developed.

  16. 33 CFR 183.435 - Conductors in circuits of 50 volts or more.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... volts or more. 183.435 Section 183.435 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Requirements § 183.435 Conductors in circuits of 50 volts or more. (a) Each conductor in a circuit that has a nominal voltage of 50 volts or more must be: (1) A conductor that has insulation listed and...

  17. 30 CFR 57.12010 - Isolation or insulation of communication conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... conductors. 57.12010 Section 57.12010 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF... conductors. Telephone and low-potential signal wire shall be protected, by isolation or suitable insulation, or both, from contacting energized power conductors or any other power source....

  18. 30 CFR 57.12005 - Protection of power conductors from mobile equipment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Protection of power conductors from mobile... NONMETAL MINES Electricity Surface and Underground § 57.12005 Protection of power conductors from mobile equipment. Mobile equipment shall not run over power conductors, nor shall loads be dragged over...

  19. 30 CFR 75.700 - Grounding metallic sheaths, armors, and conduits enclosing power conductors.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... conduits enclosing power conductors. 75.700 Section 75.700 Mineral Resources MINE SAFETY AND HEALTH... Grounding § 75.700 Grounding metallic sheaths, armors, and conduits enclosing power conductors. All metallic sheaths, armors, and conduits enclosing power conductors shall be electrically continuous throughout...

  20. 30 CFR 75.1002 - Installation of electric equipment and conductors; permissibility.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... conductors; permissibility. 75.1002 Section 75.1002 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... Wires and Trolley Feeder Wires § 75.1002 Installation of electric equipment and conductors... equipment is located within 150 feet of pillar workings or longwall faces. (b) Electric conductors...

  1. 30 CFR 77.508 - Lightning arresters, ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... power conductors and telephone wires. 77.508 Section 77.508 Mineral Resources MINE SAFETY AND HEALTH... arresters, ungrounded and exposed power conductors and telephone wires. All ungrounded, exposed power conductors and telephone wires shall be equipped with suitable lightning arresters which are adequately...

  2. 46 CFR 111.05-33 - Equipment safety grounding (bonding) conductors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Equipment safety grounding (bonding) conductors. 111.05-33 Section 111.05-33 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL... § 111.05-33 Equipment safety grounding (bonding) conductors. (a) Each equipment-grounding conductor...

  3. 46 CFR 111.05-33 - Equipment safety grounding (bonding) conductors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Equipment safety grounding (bonding) conductors. 111.05-33 Section 111.05-33 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL... § 111.05-33 Equipment safety grounding (bonding) conductors. (a) Each equipment-grounding conductor...

  4. 30 CFR 77.508 - Lightning arresters, ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... power conductors and telephone wires. 77.508 Section 77.508 Mineral Resources MINE SAFETY AND HEALTH... arresters, ungrounded and exposed power conductors and telephone wires. All ungrounded, exposed power conductors and telephone wires shall be equipped with suitable lightning arresters which are...

  5. 30 CFR 77.508 - Lightning arresters, ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... power conductors and telephone wires. 77.508 Section 77.508 Mineral Resources MINE SAFETY AND HEALTH... arresters, ungrounded and exposed power conductors and telephone wires. All ungrounded, exposed power conductors and telephone wires shall be equipped with suitable lightning arresters which are...

  6. 30 CFR 77.508 - Lightning arresters, ungrounded and exposed power conductors and telephone wires.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... power conductors and telephone wires. 77.508 Section 77.508 Mineral Resources MINE SAFETY AND HEALTH... arresters, ungrounded and exposed power conductors and telephone wires. All ungrounded, exposed power conductors and telephone wires shall be equipped with suitable lightning arresters which are...

  7. Diffusion of fast rising strong magnetic fields into conductors

    NASA Astrophysics Data System (ADS)

    Labetskaya, N. A.; Oreshkin, V. I.; Chaikovsky, S. A.; Datsko, I. M.; Kuskova, N. I.; Rud, A. D.

    2014-11-01

    The basic processes occurring in a conductor exploding in a current skinning mode are the propagation of a nonlinear magnetic diffusion wave in the conductor and the formation of low-temperature plasma at its surface. An experimental study of the phenomenon of nonlinear magnetic diffusion into conductors in magnetic fields of induction rising at a rate up to 3·109 T/s was carried out on the MIG generator capable of producing a peak current up to 2.5 MA within a rise time of 100 ns. It has been found experimentally that the average velocity of a nonlinear magnetic diffusion wave in an aluminum conductor placed in a strong magnetic field (up to 300 T) rising at a high rate (on average, 3·109 T/s) is (2.7÷3.3)·105 cm/s. This is comparable to the velocity of sound in aluminum under normal conditions and reasonably agrees with predictions of numerical simulations.

  8. Attentional flexibility and memory capacity in conductors and pianists.

    PubMed

    Wöllner, Clemens; Halpern, Andrea R

    2016-01-01

    Individuals with high working memory (WM) capacity also tend to have better selective and divided attention. Although both capacities are essential for skilled performance in many areas, evidence for potential training and expertise effects is scarce. We investigated the attentional flexibility of musical conductors by comparing them to equivalently trained pianists. Conductors must focus their attention both on individual instruments and on larger sections of different instruments. We studied students and professionals in both domains to assess the contributions of age and training to these skills. Participants completed WM span tests for auditory and visual (notated) pitches and timing durations, as well as long-term memory tests. In three dichotic attention tasks, they were asked to detect small pitch and timing deviations from two melodic streams presented in baseline (separate streams), selective-attention (concentrating on only one stream), and divided-attention (concentrating on targets in both streams simultaneously) conditions. Conductors were better than pianists in detecting timing deviations in divided attention, and experts detected more targets than students. We found no group differences for WM capacity or for pitch deviations in the attention tasks, even after controlling for the older age of the experts. Musicians' WM spans across multimodal conditions were positively related to selective and divided attention. High-WM participants also had shorter reaction times in selective attention. Taken together, conductors showed higher attentional flexibility in successfully switching between different foci of attention.

  9. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES...

  10. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES...

  11. 30 CFR 56.12011 - High-potential electrical conductors.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false High-potential electrical conductors. 56.12011 Section 56.12011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES...

  12. Improved Writing-Conductor Designs For Magnetic Memory

    NASA Technical Reports Server (NTRS)

    Wu, Jiin-Chuan; Stadler, Henry L.; Katti, Romney R.

    1994-01-01

    Writing currents reduced to practical levels. Improved conceptual designs for writing conductors in micromagnet/Hall-effect random-access integrated-circuit memory reduces electrical current needed to magnetize micromagnet in each memory cell. Basic concept of micromagnet/Hall-effect random-access memory presented in "Magnetic Analog Random-Access Memory" (NPO-17999).

  13. Conductor and Ensemble Performance Expressivity and State Festival Ratings

    ERIC Educational Resources Information Center

    Price, Harry E.; Chang, E. Christina

    2005-01-01

    This study is the second in a series examining the relationship between conducting and ensemble performance. The purpose was to further examine the associations among conductor, ensemble performance expressivity, and festival ratings. Participants were asked to rate the expressivity of video-only conducting and parallel audio-only excerpts from a…

  14. Glass ceramic ionic conductor materials and method of making

    SciTech Connect

    Badzioch, S.

    1985-03-26

    Solid, crystalline glass ceramic compositions which are useful as ionic conductor materials, especially for use as solid electrolytes in high temperature, high energy density storage batteries. The glass ceramics are derived from sodium or calcium borates containing one or more metal halide, preferably the chlorides and bromides of the metals from Group 2 to 8 of the Periodic Table of the Elements.

  15. Performance analysis of the toroidal field ITER production conductors

    NASA Astrophysics Data System (ADS)

    Breschi, M.; Macioce, D.; Devred, A.

    2017-05-01

    The production of the superconducting cables for the toroidal field (TF) magnets of the ITER machine has recently been completed at the manufacturing companies selected during the previous qualification phase. The quality assurance/quality control programs that have been implemented to ensure production uniformity across numerous suppliers include performance tests of several conductor samples from selected unit lengths. The short full-size samples (4 m long) were subjected to DC and AC tests in the SULTAN facility at CRPP in Villigen, Switzerland. In a previous work the results of the tests of the conductor performance qualification samples were reported. This work reports the analyses of the results of the tests of the production conductor samples. The results reported here concern the values of current sharing temperature, critical current, effective strain and n-value from the DC tests and the energy dissipated per cycle from the AC loss tests. A detailed comparison is also presented between the performance of the conductors and that of their constituting strands.

  16. Development of flat conductor cable for commercial and residential wiring

    NASA Technical Reports Server (NTRS)

    Carden, J. R.

    1977-01-01

    The overall spectrum of the space technology spin-off development project: development of Flat Conductor Cable (FCC) for commercial and residential wiring, is presented. A discussion of the background, program milestones, industry participants, system outgrowth, hardware availability, cost estimates, and overall status of the program is presented for the 1970-to-present time period.

  17. Undergraduate Conductors' and Conducting Teachers' Perceptions of Basic Conducting Efficacy

    ERIC Educational Resources Information Center

    Silvey, Brian A.; Baumgartner, Christopher M.

    2016-01-01

    The purpose of this study was to examine undergraduate conductors' and conducting teachers' perceptions about basic conducting efficacy. At the beginning and end of the semester, undergraduate students (N = 19) enrolled in a basic conducting course (a) were surveyed about the importance of certain skills necessary for being an effective conductor…

  18. Aharonov-Bohm oscillations in singly connected disordered conductors.

    PubMed

    Aleiner, I L; Andreev, A V; Vinokur, V

    2015-02-20

    We show that the transport and thermodynamic properties of a singly connected disordered conductor exhibit quantum Aharonov-Bohm oscillations as a function of the total magnetic flux through the sample. The oscillations are associated with the interference contribution from a special class of electron trajectories confined to the surface of the sample.

  19. Exploring a Metamorphosis: Identity Formation for an Emerging Conductor

    ERIC Educational Resources Information Center

    Ponchione, Cayenna

    2013-01-01

    Exploring the manner in which professional identity formation in emerging conductors is entangled with the cultural context of orchestras, I focus on the amorphous evolution from a student identity to that of a professional, illuminating some underlying social conditions of the ever-elusive profession of conducting. Prevailing assumptions about…

  20. Exploring a Metamorphosis: Identity Formation for an Emerging Conductor

    ERIC Educational Resources Information Center

    Ponchione, Cayenna

    2013-01-01

    Exploring the manner in which professional identity formation in emerging conductors is entangled with the cultural context of orchestras, I focus on the amorphous evolution from a student identity to that of a professional, illuminating some underlying social conditions of the ever-elusive profession of conducting. Prevailing assumptions about…