Title :
Evolution of core density of Ag-clad Bi-2223 tapes during process
Author :
Jiang, J. ; Cai, X.Y. ; Chandler, J.G. ; Rikel, M.O. ; Hellstrom, E.E. ; Parrella, R.D. ; Yu, Dingan ; Li, Q. ; Rupich, M.W. ; Riley, G.N. ; Larbalestier, D.C.
Author_Institution :
Appl. Supercond. Center, Wisconsin Univ., Madison, WI, USA
fDate :
3/1/2001 12:00:00 AM
Abstract :
The porosity and its effect on critical current density Jc of Ag-clad (Bi,Pb)2Sr2Ca2Cu3Ox (Bi-2223) tapes throughout important steps in their thermomechanical treatment was investigated by using mass density measurement, microstructural observation, and superconducting property characterization. The relative mass density of the final filament for 19 filament tape was less than 75%, even though the Jc is ~50 kA/cm2 (77 K, 0 T). The mass density in monofilaments reached 90%, because retrograde densification during the first heat treatment (HT1) was less or even absent. Well textured Bi-2223 grain growth could result in a significant densification during the first HT in the monofilament composite. Our results hint at considerable variability in this important property of Bi-2223 tape
Keywords :
bismuth compounds; calcium compounds; composite superconductors; critical current density (superconductivity); crystal microstructure; densification; grain growth; heat treatment; high-temperature superconductors; lead compounds; multifilamentary superconductors; porosity; silver; strontium compounds; superconducting tapes; texture; thermomechanical treatment; (Bi,Pb)2Sr2Ca2Cu3O x; (BiPb)2Sr2Ca2Cu3O; 19 filament tape; 77 K; Ag; Ag-clad Bi-2223 tapes; HTSC; core density; critical current density; heat treatment; mass density; microstructural observation; monofilaments; porosity; processing; relative mass density; retrograde densification; superconducting property characterization; thermomechanical treatment; well textured Bi-2223 grain growth; Critical current; Critical current density; Density measurement; Heat treatment; Microstructure; Multifilamentary superconductors; Powders; Superconducting filaments and wires; Superconducting films; Thermomechanical processes;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
