Title :
A comparative study of microstructure and transport critical current in cold rolled, cold uniaxially pressed and low load hot uniaxially pressed Ag-(Bi,Pb)/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub x/ tape
Author :
James, M.P. ; Glowacki, B.A. ; Evetts, J.E. ; Ashworth, S.P. ; Garre, R. ; Conti, S.
Author_Institution :
Interdisciplinary Res. Centre in Superconductivity, Cambridge Univ., UK
fDate :
6/1/1995 12:00:00 AM
Abstract :
The microstructure and transport critical current of cold rolled, cold uniaxially pressed, and low load hot uniaxially pressed Ag-(Bi,Pb)/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub x/, tape has been investigated. The transverse and longitudinal transport current measurements show strong correlation with morphological non-uniformities induced by the cold deformation processes. The aim of low load hot uniaxial pressing is to increase the density of the ceramic core and reduce the anisotropic nature of the critical current induced during the cold deformation processes. The deformation mechanisms of the silver and ceramic core when under load have been studied, and a deformation mechanism map has been constructed. Experimental investigation of the low load region over a range of temperatures has been carried out.<>
Keywords :
bismuth compounds; calcium compounds; cold rolling; critical currents; crystal microstructure; high-temperature superconductors; hot pressing; lead compounds; materials preparation; silver; strontium compounds; superconducting tapes; Ag-(Bi,Pb)/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub x/ tape; Ag-(BiPb)/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O; anisotropic nature; ceramic core; cold deformation; cold rolled tape; cold uniaxially pressed tape; high temperature superconductors; longitudinal transport current; low load hot uniaxially pressed tape; microstructure; morphological nonuniformities; strong correlation; transport critical current; transverse transport current; Ceramics; Conducting materials; Critical current; Materials science and technology; Microstructure; Powders; Pressing; Proposals; Silver; Superconductivity;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
