FABRICATION OF (BI, PB)(2)SR2CA2CU3OX HIGH-T-C SUPERCONDUCTING CURRENT LEADS

High critical current density is a key factor for applications such as current leads. The (Bi, Pb)(2)Sr2Ca2Cu3Ox high-T-c superconductor has been investigated in terms of the critical current density. The Bi-22 23 superconducting current leads were made by repeated application of cold isostatic pressing (CIP) and solid-state sintering. The Bi-2223 c urrent lead that was heat treated at 836 degrees C for a totally of 24 0 h in 1/13 PO2 had critical current density (J(c)) of over 610 A/cm(2 ) at 77 K. The superconducting properties of tube-type current leads w ere better than those of rods type leads, and the more the repeated CI P-sintering process was repeated, the better the J(c) was. We used X-r ay diffraction and scanning electron microscopy to investigate the rel ation between Bi-2223 formation and the heat-treatment condition and d etermined that the proper sintering temperature was 836 degrees C. The thickness of the plate-like Bi-2223 structure increased with the numb er of sintering repetitions.