The formation mechanism of Bi,Pb(2223) outgrowths in multi-filamentary tapes

We present a micro-structural study of the formation of superconducting outgrowths in multi-filamentary Bi,Pb(2223)/Ag tapes. Such bridges between the filaments have been shown to be capable of carrying sizeable currents and thus can greatly increase AC losses in these conductors. By quenching a ser...

Full description

Saved in:
Bibliographic Details
Published in:IEEE transactions on applied superconductivity 2001-03, Vol.11 (1), p.3557-3560
Main Authors: Dhalle, M., Passerini, R., Giannini, E., Witz, G., Genoud, J.-Y., Yibing Huang, Xiao-dong Su, Flukiger, R.
Format: Article
Language:English
Subjects:
Annealing
Applied sciences
Availability
Bridges
Bridges (structures)
Ceramics
Conductors
Electrical engineering. Electrical power engineering
Exact sciences and technology
Filaments
Materials
Multifilamentary superconductors
Powders
Precursors
Reaction time
Silver
Statistical analysis
Superconducting filaments and wires
Superconducting films
Superconducting tapes
Superconductivity
Transient analysis
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We present a micro-structural study of the formation of superconducting outgrowths in multi-filamentary Bi,Pb(2223)/Ag tapes. Such bridges between the filaments have been shown to be capable of carrying sizeable currents and thus can greatly increase AC losses in these conductors. By quenching a series of tapes at different reaction times, we were able to study how these outgrowths nucleate and develop. A statistical analysis of their number and length shows that they nucleate at predetermined sites and that their growth holds equal tread with the Bi,Pb(2223) formation within the filaments, both processes being governed by the availability of transient liquid. The orientation distribution of the outgrowths shows that they usually nucleate at 'dents' in the Ag/ceramic interface caused by the mechanical deformation of the inherently inhomogeneous precursor powder. The influence of precursor powder coarseness,-composition and annealing atmosphere are also discussed. The data suggest that outgrowths formation can be minimized by the use of homogeneous and fine-grained powders without hard particle agglomerates.
ISSN:1051-8223
1558-2515
DOI:10.1109/77.919832