Recent developments in processing and performance of hot stacked-sinter forged Bi2223 ceramics

Bulk-textured Bi2223 superconductors with high density have been successfully formed by the hot stacking-forging process. The grain orientation was verified by textural analysis, scanning electron microscopy observation and the critical field deduced from magneto-resistivity measurements. Transport critical current data of the textured superconductor samples were obtained using DC-measurements. According to current-voltage curves, the transition between the superconducting state and the flux-flow regime corresponds to a high transport critical current density (Jc) up to 2 x 104 A/cm2 at 77 K in a self-field. In addition, Jc, values were measured at various temperatures and different applied magnetic fields. Several textured pieces were hot-stacked under various applied stresses. This procedure leads to an increase of the sample thickness and the nominal engineering critical current (Ic) in order to use textured-Bi2223 for practical power generation