Filament aspect ratio and transport currents of Bi(2223)/Ag at 77 K

Monocore BSCCO/Ag tapes of various aspect ratio (b/a) have been made by two -axial rolling. After the final treatment (sinter or roll-sinter), the crit ical currents in self and external magnetic field as well as at various fie ld orientation have been measured. The higher the aspect ratio b/a, the hig her is the value of the self-field transport current and the better is the J(c)(B) characteristics. It is a consequence of the improved pinning and di minishing influence of weak-links as well. For small bia < 3, mainly the ra tio of two perpendicular 2223 grains orientation influences the I-c anisotr opy, while for b/a < 3 the major influence on I-c anisotropy comes from the different improvement of pnning in ab and c directions. (C) 2001 Elsevier Science B.V. All rights reserved.