Melt Textured Growth Related Process and its Characterization

Advances toward major technological applications of the bulk, high Tc superconductors have been hindered by two major barriers, i.e. the Josephson weak-links at grain boundaries, and the lack of sufficient intragrain flux pinning. It has been demonstrated that the weak link problem can be overcome by extreme alignment of grains such as in Melt-Textured-Growth (MTG) materials. Modified or improved processing by various labratories has produced further increased critical currents. However the insufficient flux pinning seems to limit the critical current density in high fields to about 10 sup 4 A/cm sup 2 at 77K, which is not satisfactory for many applications.