Effect of transverse compressive stress on the critical current and upper critical field of Nb/sub 3/Sn

Journal Article · Tue Dec 15 04:00:00 EST 1987 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.338986· OSTI ID:5957218

Ekin, J W

A large reversible degradation of the critical current of multifilamentary Nb/sub 3/Sn superconductors has been observed when uniaxial compressive stress is applied transverse to the conductor axis at 4 K. In bronze-process multifilamentary Nb/sub 3/Sn, the onset of significant degradation occurs at about 50 MPa. In an applied field of 10 T, the magnitude of the effect is about seven times larger for transverse stress than for stress applied along the conductor axis. The transverse stress effect increases with magnetic field and is associated with a reversible degradation of the upper critical field. The intrinsic effect of transverse stress on the upper critical field is about ten times greater than for axial stress. Although axial stresses on the Nb/sub 3/Sn filaments are greater than transverse stresses in most applications, the transverse stress effect will need to be considered in the internal design of large magnets because of the greater sensitivity of Nb/sub 3/Sn to transverse stress. It is shown that the transverse stress from the Lorentz force on the conductor is proportional to conductor thickness. This will place limits on conductor dimensions and the spacing between distributed reinforcement in large magnets. The effect may be particularly significant in cabled conductors where large transverse stress concentrations can occur at strand crossover points.

• Research Organization: Electromagnetic Technology Division, National Bureau of Standards, Boulder, Colorado 80303
• OSTI ID: 5957218
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 62:12; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALLOYS
COMPRESSION
CRITICAL CURRENT
CRITICAL FIELD
CURRENTS
DATA
ELECTRIC CONDUCTIVITY
ELECTRIC CURRENTS
ELECTRICAL PROPERTIES
EXPERIMENTAL DATA
INFORMATION
MAGNETIC FIELDS
MAGNETS
NIOBIUM ALLOYS
NIOBIUM BASE ALLOYS
NUMERICAL DATA
PHYSICAL PROPERTIES
STRESSES
SUPERCONDUCTIVITY
SUPERCONDUCTORS
TIN ALLOYS
TYPE-II SUPERCONDUCTORS