Title :
Microstructure and Critical Current Properties of Bi-2212 Round Wires Fabricated With Different Nominal Compositions
Author :
Matsumoto, A. ; Kitaguchi, H. ; Kumakura, H. ; Hikichi, Y. ; Nakatsu, T. ; Hasegawa, T.
Author_Institution :
Nat. Inst. for Mater. Sci., Tsukuba, Japan
fDate :
6/1/2011 12:00:00 AM
Abstract :
The microstructure and superconducting properties of Bi-2212 wires seem to be strongly influenced by the nominal composition of the starting powder. We fabricated Bi-2212 round wires with different starting compositions. The highest Jc values of 175 kA/cm2 at 4.2 K and 10 T were obtained in the Bi-rich sample with a Bi-rich composition. We carried out quenching experiments from the melting state of Bi-2212. We observed obviously smaller grains of impurity phases in the wire with high Jc than in the low-Jc wires in the melting state, which suggested that this is one of the reasons for the enhancement of the Jc values in these wires.
Keywords :
bismuth compounds; critical currents; high-temperature superconductors; melting; powders; quenching (thermal); BSCCO; Bi-2212 round wire; critical current; impurity phase; magnetic flux density 10 T; melting state; microstructure; powder; quenching experiment; temperature 4.2 K; Cooling; Heat treatment; Heating; Impurities; Microstructure; Powders; Wires; $J_{rm c}$; Bi2212; grain size; microstructure;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2010.2091096