Flux pinning properties of magnesium diboride added (Bi,Pb)-2212 superconductors

Microstructure and flux pinning properties of polycrystalline (Bi,Pb)-2212 system with varying levels (0-0.2 wt.%) of MgB2 was studied. Phase analysis, microstructural investigation and superconducting characterization were performed to evaluate the performance of the samples. The addition brought about novel features in the layered microstructure of (Bi,Pb)-2212 for critically added samples which resulted in an unusual enhancement of the flux pinning strength of the system. The self field JC (304 A/cm2) of 0.1 wt.% MgB2 added sample is more than 50% that of undoped sample (201 A/cm2) and in 0.8 T field, it is about 50 times that of pure sample at 64 K.