Title :
Fabrication of Nb3(Al,Ge) wires by using Al-Ge gas-atomized powder
Author :
Kikuchi, A. ; Iijima, Y. ; Inoue, K. ; Kosuge, M. ; Yuyama, M. ; Banno, N. ; Takeuchi, T. ; Nimori, S. ; Kusui, J.
Author_Institution :
Nat. Inst. for Mater. Sci., Tsukuba, Japan
fDate :
6/1/2003 12:00:00 AM
Abstract :
As the starting material of Nb3(Al,Ge) precursor wires, gas-atomized Al-Ge alloy powder is very promising because of the fine Ge particle dispersion in the alloy powder. The hardness of Al-Ge alloy is relatively small and well-balanced with that of the pure Nb. Therefore, no intermediate annealing is technically required for drawing a 7 × 220 × 233-core Nb/Al-Ge multifilamentary wire. Furthermore, excellent Jc-B performance without peak effects was obtained in the Nb3(Al,Ge) tape specimens through the RHQ (rapid-heating/quenching) treatment. It may be caused by the synthesizing of A15 phases transformed from Nb-Al-Ge ternary supersaturated bcc phase. The present Nb3(Al,Ge) tapes show a good agreement with Kramer´s scaling law described as Fp=A(Bc2)2.14b0.5(1-b)1.46, where A is temperature and field independent, and b=B/Bc2.
Keywords :
aluminium alloys; critical current density (superconductivity); drawing (mechanical); germanium alloys; hardness; multifilamentary superconductors; niobium alloys; powder metallurgy; quenching (thermal); superconducting tapes; A15 compound superconductor; Al-Ge alloy gas-atomized powder; Kramer scaling law; Nb3(Al,Ge) multifilamentary tape; Nb3(Al,Ge) precursor wire; Nb3(AlGe); critical current density; drawing process; fabrication process; hardness; rapid heating/quenching treatment; Annealing; Critical current density; Fabrication; Germanium alloys; Heat treatment; High temperature superconductors; Materials science and technology; Niobium alloys; Powders; Wires;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2003.812353
