Role of Silver on Superconducting Properties of BPSCCO (2223) System

Abstract

The role of silver for the superconducting properties of the Bi -Pb -Sr -Ca -Cu-0 (2223) system have been investigated systematically. Samples with various concentrations of Ag were prepared by the matrix method. D.C. resistance results showed that TJO) varied between 100-109 K for various compositions of Ag. J , measured at LNT from I-V data shows an increase with silver addition. J , decreased from 90 Amp/cmz at zero field to 16 Amp/cmz at 100 Oe. The r(0) obtained from the susceptibility data agreed with those obtained from resistance measurements. X-ray diffraction results showed that the dominant phase in BPSCCO is the high-temperature (2223) phase and the same is improved in silver added BPSCCO samples. The scanning electron micrographs indicated that silver is precipated along the grain boundaries, separating the superconducting grains. These results have showed that silver addition does not destroy the superconductivity and at the same time enhances the critical current density.

Improvement of Critical Current Density in Bi-2223 Superconductor by Ag-Doping

“…However, Ag plays the role to promote the growth rate of Bi-2223 phase, as well as to enhance the connectivity of these grains were obtained, which was evidenced by less porosities in A5 sample. The scanning electron micrographs indicated that silver is precipitated along the grain boundaries, separating the superconducting grains [19]. These results have showed that silver addition does not destroy the superconductivity and at the same time enhances the critical current density.…”