Modification of physical and structural properties of Bi1.8Pb0.4Sr2Ca2.2Cu3Oy ceramics induced by annealing

The effect of annealing temperatures on the structural and superconducting properties of Bi-2223 ceramics prepared by the solid state reaction method has been investigated. Annealing temperatures were varied from 730 to 830 °C while time was kept constant at 50 h. Electrical resistivity studies showed that samples annealed at 830 °C for 50 h have the lowest resistivity values at room temperature while critical transition temperature increases slightly. XRD data have shown that all samples contain Bi-2223 as the major one. The highest diamagnetism behavior has been found in the sample treated at 830 °C. In addition, Jc values of the samples, calculated from the hysteresis loops using the Bean's model, decreased with increasing annealing temperatures until 780 °C and increase for the highest annealing temperature which is 830 °C for this work