Research Information System
SUPERCONDUCTOR SCIENCE & TECHNOLOGY, vol.17, no.10, pp.1121-1125, 2004 (SCI-Expanded)
The complex ac susceptibility chi = chi' + chi" was measured as a function of temperature and ac field amplitude on rectangular bar shaped high-temperature superconductors with nominal composition of Bi1.6Pb0.4Sr2(Ca1-xNix)(2)Cu3Odelta (x = 0-0.10) superconducting samples prepared by the solid state reaction method. It is found that as the amount of Ni doping increases, the critical temperature T-c slowly decreases. A small amount of Ni doping (x = 0.03) increases the intergranular critical current j(cm) and the flux pinning of the Bi(Pb)-2223 system. The effective volume fraction of the grains and the field dependence of the intergranular critical current density were estimated by comparison of the maximum of the extracted matrix susceptibility and the corresponding calculated data which was obtained from hysteresis losses employing the power law critical state model.