Characteristics of micro-texture and meso-texture in (Bi, Pb)(2)Sr2Ca2Cu3O10 superconducting tapes

Grain boundary misorientation is known to limit the critical current densit y of bulk high temperature superconductors. However, the effect of mechanic al deformation on the texture evolution during powder-in-tube (PIT) process ing remains unclear, especially on the microstructural level. In the presen t work, the micro- and meso-tcxture characteristics of PIT-processed (Bi, P b)(2)Sr2Ca2Cu3O10 (Bi2223) superconductor tapes were investigated. The resu lts for micro-texture show that a/b-axes texture does exist in PIT-processe d tapes. From the meso-texture studies, it was found that a majority of the grain boundaries were formed by grains with a non-parallel c-axis. These g rain boundaries generally have low mismatch angles of up to similar to 10 d egrees. High-angle misorientation boundaries ranging up to 45 degrees are g enerally c-axis twist boundaries. Furthermore, about 40% of the grain bound aries could be coupled strongly.