Effects of PAIR (pre-annealing and intermediate rolling) process on superconducting properties of Bi2Sr2CaCu2Ox/Ag multilayer tapes

PAIR process, which is the combination of pre-annealing (PA) and intermediate rolling (IR) processes and is performed prior to melt-solidification, enhances J(c) of the Bi-2212/Ag composite tapes. The effects of pre-annealing and intermediate rolling process on microstructure and J(c) of the Bi-2212/Ag multilayer tapes fabricated by the oxide-painting method have been studied. The results show that J(c) has been increased strongly by performing pre-annealing at 800-880 degrees C and intermediate rolling with > 25% deformation. Transport J(c) of 3.3 X 10(5) A/cm(2) in magnetic field (4.2 K, 10 T) is obtained. The enhancement of J(c) is assigned to the microstructure with high grain alignment and uniformity, as well as the improvement of grain coupling by the PAIR process. (C) 1998 Elsevier Science B.V. All rights reserved.