TEION KOGAKU (Journal of Cryogenics and Superconductivity Society of Japan)
Online ISSN : 1880-0408
Print ISSN : 0389-2441
ISSN-L : 0389-2441
Volume 20, Issue 6
Displaying 1-6 of 6 articles from this issue
  • Teruo MATSUSHITA, Kaoru YAMAFUJI, Fujio IRIE
    1985 Volume 20 Issue 6 Pages 311-319
    Published: December 25, 1985
    Released on J-STAGE: February 26, 2010
    JOURNAL FREE ACCESS
    A review is given on recent topics on experimental studies of flux pinning in superconductors, while theoretical problems were discussed in the preceding review article. Here we compare experimental results with theories on the elementary pinning force and the summation problem.
    Quantitative comparison of the elementary pinning force is not possible at this moment because of ambiguity in the summation theory. The dependence of the specific pinning force of grain boundaries on the impurity parameter shows a similar tendency to the calculations by Zerweck, Yetter et al., and Welch based on the electron scattering mechanism. This observed tendency is different from the prediction from the microscopic theory of Thuneberg. The summation theories are compared with experiments within a regime of strong pinning where conventional calculation of the elementary pinning force holds safely. Observed pinning forces seem to obey the linear summation derived from the mean field approximation theory.
    The other topics such as the saturation phenomenon and the strain scaling are also discussed.
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  • Eiji FUKUSIMA, Minoru TANAKA, Sadao KOBATAKE, Hideaki MAEDA
    1985 Volume 20 Issue 6 Pages 320-324
    Published: December 25, 1985
    Released on J-STAGE: February 26, 2010
    JOURNAL FREE ACCESS
    An apparatus to measure fracture toughness at cryogenic temperatures was made, and elastic-plastic fracture toughness tests were carried out on an aluminum alloy (A5083-0) at 4K and 77K.
    The apparatus consists of a testing machine, a cryostat and various measuring systems. The acoustic emission measurement method was applied to detect a critical value of fracture toughness.
    There was found good agreement between JIC by the multispecimen method and that by the acoustic emission measurement method at 77K.
    Fracture toughness values for the aluminum alloy, were 22kJ/m2 and 20kJ/m2 at 4K and 77K, respectively.
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  • Design
    Tetsuji OKAMURA, Susumu SHIODA, Shigeharu KABASHIMA, Yoshinao SANADA
    1985 Volume 20 Issue 6 Pages 325-331
    Published: December 25, 1985
    Released on J-STAGE: February 26, 2010
    JOURNAL FREE ACCESS
    Design of a superconducting magnet to be coupled with a disk MHD generator in the closed cycle MHD experimental facility FUJI-1 is described. The superconducting magnet consists of two separated windings whose shape is of the circular Helmholtz type. A new structure between the windings has been proposed which supports magnetic force induced between the two windings and, at the same time, minimizes the heat leakage to the windings.
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  • Performance Tests
    Tetsuji OKAMURA, Susumu SHIODA, Shigeharu KABASHIMA, Yoshinao SANADA
    1985 Volume 20 Issue 6 Pages 332-336
    Published: December 25, 1985
    Released on J-STAGE: February 26, 2010
    JOURNAL FREE ACCESS
    The performance results of the tests of a superconducting magnet coupled with a disk MHD generator in the closed cycle MHD experimental facility FUJI-1 are described. At first the performance tests of the superconducting magnet only were carried out at Toshiba, secondly the magnet was coupled with the FUJI-1 facility at Tokyo Institute of Technology and the performance tests were carried out. Both these tests have shown successful performance of the magnet.
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  • Hiroshi TSUJI, Susumu SHIMAMOTO, Albert ULBRICHT, Peter KOMAREK, Heinr ...
    1985 Volume 20 Issue 6 Pages 337-349
    Published: December 25, 1985
    Released on J-STAGE: February 26, 2010
    JOURNAL FREE ACCESS
    The “Large Coil Task (LCT)”, an international project of technology development under the auspices of the IEA, is performed to develop large superconducting toroidal coils for tokamaks. The participants are the U.S.A., Switzerland, Euratom, and Japan. Among the six coils being developed under this program, domestic single coil tests of the pool boiling cooled Japanese coil and the forced flow cooled Euratom coil were carried out successfully in June 1982 and in April 1984, respectively. These two LCT coils are the first to compare experimentally the characteristics of pool boiling cooled and forced flow cooled large coils for a tokamak. Major results obtained in the two domestic tests are described for the purpose of intercomparison of the two designs.
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  • [in Japanese], [in Japanese], [in Japanese], [in Japanese], [in Japane ...
    1985 Volume 20 Issue 6 Pages 350-354
    Published: December 25, 1985
    Released on J-STAGE: February 26, 2010
    JOURNAL FREE ACCESS
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