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Magnetoresistivity and Size Effects in Aluminum Hyperconductors

  • R. K. Dawless
  • M. K. Premkumar
  • W. N. Lawless
  • C. F. Clark
  • J. C. Ho
  • Al Austen
Part of the An International Cryogenic Materials Conference Publication book series (ACRE, volume 40)

Abstract

Anomalous magnetoresistivity had been previously observed in aluminum hyper-conductors and several explanations had been proposed. A statistical matrix of 16 distinct hyperconductor designs was fabricated to evaluate the effects of deformation processes and critical design features on key properties — including magnetoresistivity. Magneto-resistance measurements have been completed at magnetic field strengths from 0 to 8 T and temperatures from 12 K to 30 K for some of the hyperconductors from this group. Although not complete, these results refute some explanations for increased magneto-resistivity in aluminum composite hyperconductors. There are possible interaction effects between magnetic field strength and filament size or condition of strain which are relevant to anomalous magnetoresistivity; and these will also be discussed.

Keywords

Magnetic Field Strength Pure Aluminum Bulk Resistivity Statistical Array Hydrostatic Extrusion 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1994

Authors and Affiliations

  • R. K. Dawless
    • 1
  • M. K. Premkumar
    • 1
  • W. N. Lawless
    • 2
  • C. F. Clark
    • 2
  • J. C. Ho
    • 3
  • Al Austen
    • 4
  1. 1.Aluminum Company of AmericaAlcoa CenterUSA
  2. 2.CeramPhysics, Inc.WestervilleUSA
  3. 3.Wichita State UniversityWichitaUSA
  4. 4.Innovare, Inc.BathUSA

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