Nb3(Al,Ge) multifilamentary wires made by the rapidly-heating/quenching process

被引:8
作者
Kikuchi, A
Iijima, Y
Inoue, K
Kosuge, M
Itoh, K
机构
[1] NRIM, Tsukuba, Ibaraki 3050047, Japan
[2] NRIM, Tsukuba, Ibaraki 3050003, Japan
关键词
Nb-3(Al; Ge) multifilamentary wire; rapidly-heating/quenching process; J(c); H-c2; TEM microstructure;
D O I
10.1109/77.919957
中图分类号
TM [电工技术]; TN [电子技术、通信技术];
学科分类号
0808 ; 0809 ;
摘要
Nb-3(Al,Ge) wires, made through the rapidly-heating/quenching process, are very promising for the applications in high fields. The precursor wires were fabricated by a rod-in-tube method, and several kinds of Al-Ge alloys (Al-2at%, 5at%, 10at% and 20at%Ge) were used for the core materials. In the ease of Al-20at%Ge alloy core, the disordered A15 phases formed directly with the rapidly-heating/quenching. It is necessary for the as-quenched wires to be additionally annealed in order to improve the superconducting properties through the recovery of the long-range order of A15 crystal structure. The best values of T-c and H-c2 (4.2 K) for the Nb3(AI,Ge) wires were 19.4 K and 39 T, respectively. Furthermore, J(c) apparently increased with decreasing the AI-Ge alloy core size in the precursor wires. J(c) (4.2 K, 25 T) of 0.3 mum-core Nb-3(Al,Ge) wire exceeds 150 A/mm(2), which was about two times larger than that of 1.5 mum-core Nb3(Al,Ge) wire. The results of TEM observation revealed that the reduction of Al-Ge alloy diameter enhanced the volume fraction of the A15-Nb-3(Al,Ge) phases through increasing of diffusion pairs density in the composite. The diameter of A15 crystal grains is about 100 nm, and scarcely dependent on the Al-Ge alloy core size.
引用
收藏
页码:3984 / 3987
页数:4
相关论文
共 5 条
[1]   UPPER CRITICAL FIELDS OF HIGH-TEMPERATURE SUPERCONDUCTING NB1-Y(A11-XGEX)Y AND NB3A1 - MEASUREMENTS OF HC2 GREATER THAN 400 KG AT 4.2 DEGREES K [J].
FONER, S ;
MCNIFF, EJ ;
MATTHIAS, BT ;
GEBALLE, TH ;
WILLENS, RH ;
CORENZWI.E .
PHYSICS LETTERS A, 1970, A 31 (07) :349-&
[2]  
IIJIMA Y, 1994, ADV CRYOG ENG, V40, P899
[3]  
IIJIMA Y, 1994, P 15 INT C MAG TECHN, P1040
[4]  
Suenaga M., 1981, Superconductor Materials Science. Metallurgy, Fabrication, and Applications. Proceedings of a NATO Advanced Study Institute on the Science and Technology of Superconducting Materials, P201
[5]   Strain effects in Nb3Al multifilamentary conductors prepared by phase transformation from bcc supersaturated-solid solution [J].
Takeuchi, T ;
Iijima, Y ;
Inoue, K ;
Wada, H ;
tenHaken, B ;
tenKate, HHJ ;
Fukuda, K ;
Iwaki, G ;
Sakai, S ;
Moriai, H .
APPLIED PHYSICS LETTERS, 1997, 71 (01) :122-124