Title :
Phase formation in Ag-sheathed (Bi,Pb)/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub 10/ tapes using a one- and two-powder process with and without Ag additions
Author :
Parrella, R.D. ; Sung, Y.S. ; Hellstrom, E.E.
Author_Institution :
Appl. Supercond. Center, Wisconsin Univ., Madison, WI, USA
fDate :
6/1/1995 12:00:00 AM
Abstract :
The formation of (Bi,Pb)/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub 10/ ((Bi,Pb)2223) in Ag-sheathed tapes was compared for two different powder processing techniques. In one technique, a phase assemblage of (Bi,Pb)/sub 2/Sr/sub 2/CaCu/sub 2/O/sub 8/ ((Bi,Pb)2212), (Ca,Sr)/sub 2/CuO/sub 3/, and CuO was produced in a single powder processed by Aerosol Spray Pyrolysis (ASP). This is called a 1-powder process. In the other technique, the same phase assemblage was produced by mixing a precursor powder composed of (Bi,Pb)2212 with a second precursor powder composed of Ca/sub 2/CuO/sub 3/ and CuO. (Both of the precursor powders were also processed by ASP.) This is called a 2-powder process. A set of tapes were made by the 1-powder process that contained 1, 5, and 10 wt.% Ag. The tape with 1 wt.% Ag yielded a microstructure of nearly phase pure (Bi,Pb)2223.<>
Keywords :
bismuth compounds; calcium compounds; composite superconductors; high-temperature superconductors; lead compounds; powder technology; silver; spray coating techniques; strontium compounds; superconducting tapes; (BiPb)/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O-Ag; Ag-sheathed tapes; aerosol spray pyrolysis; high temperature superconductor; microstructure; one-powder process; phase formation; two-powder process; Aerosols; Annealing; Application specific processors; Assembly; Microstructure; Powders; Silver; Spraying; Strontium; Superconducting films;
Journal_Title :
Applied Superconductivity, IEEE Transactions on