The Influence of Sintering Time in High and Low Density Bi-2223 Superconductor
The effects of sintering time in high and low density Bi-2223 phase formation have been investigated. The samples were prepared by the solid-state reaction method at various sintering times ranging from 24, 48, 72 and 96 hours. Sucrose was added during palletization and after heated at 400°C for two hours the sucrose was removed and hence low density sample was created. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and critical current density. The transition temperature varies between 102 K and 96 K with increasing of sintering times. The optimal sintering time of the samples Bi-2223 system was found at 850°C for 72 hours. The critical current density,JCof high density and low density Bi-2223 was measured to be 7.547 A/cm2and 8.333 A/cm2respectively at 77 K under zero magnetic field. The critical current density,JCand superconductivity transition temperature,TCof low density were found to be higher than the pure samples. The critical transition temperature increased with a short gap betweenTConsetandTC zero. The most intense peak in the XRD pattern of sample at sintering time 72 hours belong to the high-TCphase which also indicates an increase in the volume fraction of the high-TCphase with optimum sintering time.