Title :
Effect of third-element additions on the upper critical field of bronze-processed Nb3Sn
Author :
Kurahashi, H. ; Itoh, K. ; Matsumoto, S. ; Kiyoshi, T. ; Wada, H. ; Murakami, Y. ; Yasunaka, H. ; Hayashi, S. ; Otani, Y.
Author_Institution :
Tsukuba Magnet Lab., Nat. Inst. for Mater. Sci., Tsukuba, Japan
fDate :
6/1/2005 12:00:00 AM
Abstract :
A direct measurement has been carried out of the upper critical magnetic field (Bc2) of bronze-processed Nb3Sn wires with and without the addition of various third-elements to the Cu-Sn matrix using a hybrid-magnet at the Tsukuba Magnet Laboratory at fields up to 30 T. The Bc2 of pure Nb3Sn rose with increasing heat treatment temperature up to 880°C (Bc2=24.7 T at 4.2 K), above which point it decreased rapidly. Its value was independent of the Sn content in the bronze. In the Ti addition samples, the optimum value of Bc2 (=26 T at 4.2 K) depended on both Ti content and heat treatment temperature. When Sb was added, Bc2 showed a sharp fall below a heat treatment of 700°C due to the replacement at the Sn site by a Sb atom.
Keywords :
heat treatment; multifilamentary superconductors; niobium alloys; superconducting tapes; tin alloys; type II superconductors; 30 T; 4.2 K; Cu-Sn matrix; Nb3Sn; Nb3Sn wires; Tsukuba Magnet Laboratory; bronze process; critical magnetic field; heat treatment temperature; hybrid magnet; superconductor; Conductors; Heat treatment; Laboratories; Magnetic field measurement; Multifilamentary superconductors; Niobium; Superconducting magnets; Temperature; Tin; Wires; Bronze process; critical magnetic field; superconductor;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2005.848914
