Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Correlation of transport and magnetic critical currents in melt-processed YBa2Cu3O7−δ thick films (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 1720-1725 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Transport critical current measurements have been carried out on melt-processed thick films of YBa2Cu3O7−δ on yttria-stabilized zirconia in fields of up to 8 T both within grains and across grain boundaries. These measurements yield Jc values of ∼3000 A cm−2 at 4.2 K and zero magnetic field and 400 A cm−2 at 77 K and zero magnetic field, taking the entire sample width as the definitive dimension. Optical and scanning electron microscopy reveals that the thick-film grains consist typically of a central "hub'' region ∼50 μm in diameter, which is well connected to radial subgrains or "spokes'' which extend ∼1 mm to define the complete grain structure. Attempts have been made to correlate the transport measurements of inter- and intra-hub-and-spoke (H-S) critical current with values of this parameter derived previously from magnetization measurements. Analysis of the transport measurements indicates that current flow through H-S grains is constrained to paths along the spokes via the grain hub. Taking the size of the hub as the definitive dimension yields an intra-H-S grain Jc of ∼60 000 A cm−2 at 4.2 K and 0 T, which is in reasonable agreement with the magnetization data. Experiments in which the hub is removed from individual grains confirm that this feature determines critically the Jc of the film.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.357687
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Microstructural and magnetization studies of sintered and melt-textured Y-Ba-Cu-O (1989)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 66 (1989), S. 5930-5934 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: For bulk applications, high-Tc superconductors generally require high critical current density, Jc. This paper reports two methods of producing high-Tc ceramic wires. The first is an extrusion and sintering route where Jc is routinely 600–1000 A cm−2. The second is by melt texturing or directional solidification where we have achieved in excess of 7000 A cm−2 by direct measurement at 77 K in zero field. However, the ease with which wire may be extruded and sintered is attractive and functioning devices have already been manufactured using this route. Fabrication of devices is facilitated by a unique processing route that has resulted in the strongest bulk ceramic yet reported (bend strength 〉200 MPa). The melt-texturing route and the problems associated with it are examined and compared with the extrusion and sintering route. The processing and the microstructures associated with the directionally solidified YBa2Cu3Ox will be examined in detail as will the resultant superconducting properties, in particular the magnetization.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.343618
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    High Q YBa2Cu3Ox cavities (1992)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 60 (1992), S. 1378-1380 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Melt-processed YBa2Cu3Ox thick film components for resonant cavities have been produced on yttria stabilized zirconica substrates. A variety of cavities have been constructed incorporating both copper and superconducting components and the TE011 modes have been examined. The highest unloaded Q factor measured was 715 688 for the TE011 mode of an all superconducting cavity at 77 K and 5.66 GHz in the Earth's magnetic field. This corresponds to a surface resistance of 1.09 mΩ over a total surface area in excess of 230 cm2. Cooling this cavity within a mumetal shield increased the unloaded Q factor by approximately 5%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.107296
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Low surface resistance in YBa2Cu3Ox melt-processed thick films (1991)
    [s.l.] : Nature Publishing Group
    Nature 349 (1991), S. 680-683 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Because the of the quadratic frequency dependence of Rs in superconductors1, as opposed to the square-root dependence in normal metals, there is a great incentive to reduce Rs in superconductors so that operation of devices below the cross-over frequency benefit from a lower Rs than that of a ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/349680a0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    A simple way to make tough ceramics (1990)
    [s.l.] : Nature Publishing Group
    Nature 347 (1990), S. 455-457 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] By far the most successful method to date for producing high-toughness composites is the infiltration of a ceramic fibre preform with a gaseous ceramic precursor5. Several months are required to produce parts only a few millimetres thick, however, and several steps of surface grinding are ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/347455a0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    High-capacity superconducting current leads of Y1Ba2Cu3O7−x (1990)
    Springer
    Journal of superconductivity 3 (1990), S. 221-226 
    Details
    ISSN: 1572-9605
    Keywords: Current leads ; Y1Ba2Cu3O7−x ; high-current capacity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Notes: Abstract We have fabricated and measured a high-capacity superconducting current lead composed of a Y1Ba2Cu3O7−x cylinder, 20 cm long and 0.9 cm2 cross section. A steady-state, d.c., critical current of 225 A at a temperature of 77 K was measured in this sample, using a voltage criterion of 2×10−7 V/cm (p = 8×10−10 ohm-cm). This current was limited by the currentinduced, self magnetic field. To our knowledge this is the largest d.c. critical current so far reported in a Y1Ba2Cu3O7−x sample and demonstrates the possibility of using hightemperature superconducting HTS materials for current leads to low-temperature superconducting LTS magnets or in power distribution systems.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00624512
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Hardness anisotropy and its dependence on composition in sodium tungsten bronzes and rhenium trioxide single crystals (1979)
    Springer
    Journal of materials science 14 (1979), S. 159-164 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Hardness anisotropy measurements using a Knoop diamond indenter on {0 0 1} and {0 0 1} surfaces of Na x WO3 (0.4〈x〈0.8) and ReO3 single crystals with the cubic perovskite structure show that hardness is determined by slip on {1 1 0} 〈1 1 0〉. Room temperature slip is produced by Knoop and Vickers microhardness indentations on polished crystals and confirms the active slip system identified from a consideration of anisotropy. The hardness anisotropy is more pronounced as the sodium content of the crystals increases. The data suggests that hardness of Na x WO3 is dependent on both plane and direction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01028339
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    The linear expansion of yttria-stabilized zirconia at 77 K using a microwave ring resonator method (1993)
    Springer
    Journal of materials science 12 (1993), S. 878-879 
    Details
    ISSN: 1573-4811
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00455604
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Melt processing of superconducting YBa2Cu3O7−∂ thick films on AgPd substrates via atmosphere control (2000)
    Springer
    Journal of materials science 35 (2000), S. 6105-6110 
    Details
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Superconducting YBa2Cu3O7−∂ (123) c-axis textured thick films have been prepared on AgPd substrates by a modified screen printing and melt processing method. Heating the samples in an inert gas (N2) has enabled melt processing to take place at lower temperatures than conventional YBCO thick film processing in O2. The atmosphere is switched to p(O2) = 100% at peak temperature in order to initiate the crystallisation of the 123 phase. Variation in properties of the films with changes in the peak processing temperature has been investigated. Samples processed at peak temperatures of ≥980°C show better microstructures and superconducting properties than those processed at lower temperatures. Quenching experiments have also been performed in order to investigate further the phase relationships and crystallisation mechanism of the 123 phase.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1026736001258
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...