Title :
Critical current and n-value of Nb/sub 3/Sn conductors for the wide bore 900 MHz NMR magnet
Author :
Dixon, I.R. ; Markiewicz, W.D. ; Pickard, K.W. ; Swenson, C.A.
Author_Institution :
Nat. High Magnetic Field Lab., Tallahassee, FL, USA
fDate :
6/1/1999 12:00:00 AM
Abstract :
Electrical characterization of Nb/sub 3/Sn superconductor for application in a 900 MHz wide bore NMR magnet is performed. The magnet has five coils containing bronze process niobium-tin superconductor. Short samples of each of the five conductor types are reacted in a similar manner as the coils and the critical currents are measured. The samples are mounted across a Ti-6Al-4V shunt and the tests are conducted in background fields up to 19.45 T and at temperatures of 4.2 K and 1.8 K. Descriptions of the superconductor configurations and experimental procedure are given. The measured critical current and the current-voltage relationship of each conductor as expressed by the index number (n-value) are presented.
Keywords :
NMR spectrometers; critical current density (superconductivity); niobium alloys; superconducting coils; superconducting magnets; tin alloys; type II superconductors; 1.8 K; 19.45 T; 4.2 K; 900 MHz; Nb/sub 3/Sn; Nb/sub 3/Sn conductors; Ti-6Al-4V shunt; background fields; bronze process niobium-tin superconductor; coils; critical current; critical currents; current-voltage relationship; electrical characterization; index number; n-value; superconductor configurations; wide bore 900 MHz NMR magnet; Boring; Conductors; Critical current; Current measurement; Magnetic field measurement; Niobium; Nuclear magnetic resonance; Superconducting coils; Superconducting magnets; Tin;
Journal_Title :
Applied Superconductivity, IEEE Transactions on