An Improved Method for Making High Field Critical Current Estimates and Its Application to High Current MJR Wires

  • P. D. Jablonski
  • J. C. McKinnell
Part of the Advances in Cryogenic Engineering book series (ACRE, volume 44)


Recent advances in commercial style Modified Jelly Roll (MJR) wires have increased the non-copper Jc (10T) from 2,300 A/mm2 to over 3,000A/mm2. Such promising results at intermediate fields peaked our interest in developing a better estimate for the high field Jc (>16T). For some time we have utilized Kramer fits to estimate Jc at fields beyond the highest tested. While this is useful for showing trends, it is much less useful for the magnet designer since an overestimate is observed. This overestimate can be on the order of 50% or more at 20T. In this paper we present our latest high current results as well as our method for correcting high field extrapolated Jc. This correction provides estimates typically within 3% of the actual results and, in general, underestimates rather than overestimates Jc (a much better situation for the magnet designer).


High Field Critical Current Density Magnet Designer Applied External Magnetic Field High Performance Standard 
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Copyright information

© Springer Science+Business Media New York 1998

Authors and Affiliations

  • P. D. Jablonski
    • 1
  • J. C. McKinnell
    • 2
  1. 1.Wah ChangAlbanyUSA
  2. 2.Oxford InstrumentsCarteretUSA

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