Glass-forming ability and superconductivity in Bi2−xPbxSr2CaCu2Oy glass-ceramics

The glass-forming ability and superconducting properties in the Bi 2− x Pb x Sr 2 CaCu 2 O y glass-ceramics were examined by using a conventional melt-quenching method. The complete glassy samples were obtained in the composition range of x =0−1.0. The glass transition and crystallization temperatures of the glasses decreased monotonically with increasing Pb content. It was found from the ac complex susceptibility measurements that the onset temperature of superconducting transition decreased with increasing Pb content but the superconducting weak links at grain boundaries among the low- T c phases were greatly improved due to the Pb doping. The significant grain growth of the low- T c phase was observed in the Pb-doped glass-ceramics.