Various Processing Techniques for Critical Current Enhancement in High T sub C Superconductors

In order to achieve high critical currents, the bulk high T sub c superconductors have to be processed for i) near perfect grain alignment to overcome the weak-link problem and ii) increased density of flux-pinning defects. Proven grain-alignment techniques include melt-textured-growth (or modified melt processing) in Y-Ba-Cu-O, and mechanical alignment of grains by wire drawing/rolling in Bi-Pb-Sr-Ca-Cu-O. The Processing and critical current properties related to these alignment techniques will be reviewed, and the future implications will be discussed.