Effects of texturing mechanisms on the critical current density in sintered High-Tc Bi-2223 superconductors

Ac susceptibility measurements on ceramic samples with the nominal composition of Bi1.8Pb0.4Sr2Ca2Cu3O10-delta prepared by various pressing pressures on the pellets (355, 533, 711 and 1067 MPa) and different directional cooling temperature rates (20, 10, and 5 degreesC/h) using a directional solidification approach with a stationary Pt crucible in a strong temperature gradient have been carried out. The intergranular critical current density (J(cm)) distribution has been calculated from ac susceptibility measurements by using Bean's and Kim's critical state models. It is observed that the critical current density improved with increasing pressing pressure and decreasing directional cooling temperature rates.