THE GLASS CERAMIC ROUTE TO HIGH-TC SUPERCONDUCTORS IN THE BI-CA-SR-CU-O SYSTEM

A superconducting ceramic of composition Bi1.5CaSr1.5Cu2Ox has been prepared by the glass-ceramic route by melting in platinum, quenching between aluminium plates to form a glass then heat treating in air at 824 degrees C. This material has Tc (onset)=101 K and Tc(zero)=90 K. It has been studied by X-ray diffraction, differential thermal analysis and SEM together with EDX analysis. Its electrical properties are compared with those of Bi2Ca1.5Sr1.5Cu2Ox also prepared as a glass ceramic but the latter does not have such good superconducting properties.