The influence of elevated magnetic fields on the texture formation of melt-processed Bi-2212

Melt-processing of BSCCO high-T-c superconductors (HTS) under an elevated magnetic field is an effective technique for producing superconductors with enhanced critical current. This result is a consequence of the high degree of crystallographic texture achieved in the polycrystalline superconductor processed under a high magnetic field. Possible mechanisms for the orientation of Bi-2212 plate-like crystals under the influence of a magnetic field are analyzed, in particular, the orientation of Bi-2212 superconductor crystals during nucleation, crystal growth and grain growth. In order to understand the relevance of each of these mechanisms, the effect of an applied magnetic field during the different stages of the partial-melt process is studied. Experimental results confirm that most of the alignment is achieved in the early stages of crystal growth. (C) 2000 Elsevier Science B.V. All rights reserved.