Melt processing of bulk high T/sub c/ superconductors and their application

The authors report a melt-powder-melt-growth (MPMG) process which results in high J/sub c/ for bulk Y-Ba-Cu-O superconductors. The Y-Ba-Cu-O pellets or powders are melt quenched. The quenched plates are crushed into powder and mixed well. The powder is then compacted into desired shapes, remelted, and slowly cooled in a thermal gradient. When the starting composition is changed from the 1:2:3 stoichiometry toward the Y/sub 2/BaCuO/sub 5/