Quantitative Electron Microscopy of (Bi,Pb)2Sr2Ca2Cu3O10+δ/Ag Multifilament Tapes During Initial Stages of Annealing |
| |
Authors: | Sara Bals Jo Verbeeck Gustaaf Van Tendeloo Yi-Lin Liu Jean-Claude Grivel |
| |
Affiliation: | EMAT, University of Antwerp (RUCA), B-2020 Antwerp, Belgium; Materials Research Department, RisøNational Laboratory, DK-4000 Roskilde, Denmark |
| |
Abstract: | The microstructural and compositional evolution during initial annealing of a superconducting (Bi,Pb)2Sr2Ca2Cu3O10+δ/Ag tape is studied using quantitative transmission electron microscopy. Special attention is devoted to the occurrence of Pb-rich liquids, which are crucial for the Bi2Sr2CaCu2O8+δ to (Bi,Pb)2Sr2Ca2Cu3O10+δ transformation. Ca and/or Pb-rich (Bi,Pb)2Sr2CaCu2O8+δ grains dissolve into a liquid, which reacts with Ca-rich phases to increase the liquid's Ca-content. This leads to (Bi,Pb)2Sr2Ca2Cu3O10+δ formation. Apparently, a Ca/Sr ratio of around 1 is sufficient to keep (Bi,Pb)2Sr2Ca2Cu3O10+δ nucleation going. It is confirmed that Ag particles are transported from the Ag-sheath into the oxide core by the liquid and not by mechanical treatment of the tape. |
| |
Keywords: | |
|
|