HIGH-TC SUPERCONDUCTING GLASS-CERAMICS

This paper reviews glass formation and crystallization and the superconducting properties of glass-ceramics in the Bi(Pb)-Sr-Ca-Cu-O system. There has been great progress in the superconducting glass-ceramics field in the short period following the discovery of Bi-based superconductors. Many glasses, such as those with the compositions Bi2Sr2CaCu2O(x) and (Bi, Pb)2Sr2Ca2Cu3O(x), can be prepared using the conventional melt-quenching method. The glasses are crystallized by annealing at temperatures above 500-degrees-C, and are converted into superconductors with a large amount of superconducting low-T(c) phase (critical transition temperature (T(c)) = 85 K) or high-T(c) phase (T(c) = 105 K). It has been amply confirmed that the Bi(Pb)-based glass-ceramics (i.e. crystallized glasses) exhibit superconductivity with T(c) above 100 K. More extensive study will lead to the fabrication of high-performance superconductors such as fibres with high critical current densities.