Strain Scaling Law and the Prediction of Uniaxial and Bending Strain Effects in Multifilamentary Superconductors

  • J. W. Ekin
Part of the Cryogenic Materials Series book series (CRYMS)


Recently it was shown1 that at 4.2 K the critical pinning-force density F in a wide range of practical conductors obeys a scaling law of the form:
$$F = {[B_{c2}^*(\varepsilon )]^n}\,f(b)$$
where \(B_{c2}^*\) is the bulk upper-critical field at 4.2 K and f(b) is a function only of the reduced magnetic field \(b \equiv B/B_{c2}^*.\) For Nb3Sn conductors, n = 1 ± 0.3. This relation was found to hold for both compressive and tensile intrinsic strain, and is expected to be limited in validity only by the irreversible strain point2 where filament breakage becomes significant (typically at intrinsic tensile strains greater than 0.4 – 0.7% for most highly-reacted Nb3Sn conductors2).


Critical Current Strain Limit Average Scheme Uniaxial Strain Irreversible Strain 
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Copyright information

© Plenum Press, New York 1980

Authors and Affiliations

  • J. W. Ekin
    • 1
  1. 1.Thermophysical Properties DivisionNational Bureau of StandardsBoulderUSA

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