DocumentCode :
840416
Title :
Phase formation and evolution, texturing and current transport in Ag/Bi2212 PIT monofilamentary tapes
Author :
Rodrigues, Durval, Jr. ; Bigansolli, Antonio R. ; Cursino, Eliana ; Papini, Paulo S.
Author_Institution :
Grupo de Supercondutividade, Dept. de Engenharia de Materiais, Lorena, Brazil
Volume :
15
Issue :
2
fYear :
2005
fDate :
6/1/2005 12:00:00 AM
Firstpage :
2546
Lastpage :
2549
Abstract :
Superconducting tapes of ceramic material capable of transporting high current densities at high operation temperatures have been revealed as promising conductors in applied superconductivity. Tapes of Ag/Bi2212 present excellent characteristics and their processing techniques are being improved. This work presents a study on the formation of phases and the texturing behavior of Ag/Bi2212 monofilamentary tapes after several heat treatments with different cooling rates from 890°C to 830°C and silver doping, allowing an optimization of the heat treatment profiles aiming the obtainment of close to stoichiometric superconducting phases with high texturing. The tapes were fabricated using Bi2212 precursor powder and the powder-in-tube (PIT) method. The powder was pressed inside the Ag tube, and the set was mechanically deformed by swaging and rolling to the final thickness of 150 μm. After heat treatment, the samples were characterized by X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) equipped with Energy Dispersive Spectrometer (EDS). The results show the effect of each heat treatment profile on the microstructure and superconducting characteristics of the Ag/Bi2212 tapes, as well as they show the ways to obtain the best texturing of the samples aiming high current transport.
Keywords :
X-ray chemical analysis; X-ray diffraction; bismuth compounds; calcium compounds; critical current density (superconductivity); crystal microstructure; heat treatment; high-temperature superconductors; powders; rolling; scanning electron microscopy; silver; strontium compounds; superconducting tapes; 1 hour; 150 micron; 200 C; 3 mm; 5 mm; 700 C; 890 to 830 C; Ag/Bi2212 PIT monofilamentary tapes; Bi2212 precursor powder; Bi2Sr2CaCu2O8-Ag; EDS; SEM; XRD; applied superconductivity; ceramic material; cooling rates; current transport; energy dispersive spectrometer; heat treatment optimization; heat treatment profiles; high current density; high operation temperatures; mechanical deformation; microstructure; phase evolution; phase formation; powder-in-tube method; processing techniques; scanning electron microscopy; silver doping; stoichiometric superconducting phases; superconducting tapes; texturing behavior; x-ray diffraction; Ceramics; Conducting materials; Current density; Heat treatment; Powders; Scanning electron microscopy; Superconducting films; Superconducting materials; Superconductivity; Temperature; Bi2212; microstructure; monofilamentary tapes; texturing; transport properties;
fLanguage :
English
Journal_Title :
Applied Superconductivity, IEEE Transactions on
Publisher :
ieee
ISSN :
1051-8223
Type :
jour
DOI :
10.1109/TASC.2005.847645
Filename :
1440185
Link To Document :
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