Effect of post-annealing on critical current density of (Bi,Pb)-2223/Ag tapes

摘要

The effect of post-annealing on critical current density of (Bi,Pb)-2223/Ag tapes has been investigated. The fully reacted (Bi,Pb)-2223/Ag multifilament tapes were post-annealed in different processing parameters, including postannealing temperature, dwelling time and oxygen partial pressure. Experimental results show that post-annealing at low temperature in reduced oxygen partial pressure can improve the critical current density. With decreasing oxygen partial pressure. the optimal temperature range of post-annealing shifts to lower temperature. The effect of post-annealing could be related to the increase of (Bi,Pb)-2223 phase and the formation of Pb3Sr2.5Bi0.5Ca2CuOy (3321 phase) as well as the improvement of gain connectivity. (C) 2004 Elsevier B.V. All rights reserved.