Magnetic properties of superconducting ceramics Bi _1.6 Pb _0.4 Sr ₂ Ca ₂ Cu ₃ O _10+d prepared by different methods

Abstract

Samples of Bi 2-x Pb x Sr 2 Ca 2 Cu 3 O 10+d have been elaborated by use of three different methods. The first method uses a precursor obtained from CaCO 3 , SrCO 3 and CuO. In the second method the CuO is not used to obtain the precursor while the third method is without precursor. At each step of the elaboration, the samples are analyzed by means of X-ray powder diffraction. Final samples are characterized by Scanning Electron Microscopy. The three methods allows to obtain a pure Bi 2-x Pb x Sr 2 Ca 2 Cu 3 O 10+d phase. AC and DC Susceptibility measurements show the same critical temperature, T c , but different dependance temperature when the constant applied field is changed. Differences are also observed in magnetization measurements at 5 and 80 K. The results are correlated with the different granular structures obtained by the three methods.