Superconducting Properties of High-Tc Ceramics

Superconducting properties are studied through electrical resistivity, magnetic susceptibility and X-ray diffraction on the high temperature superconductor Y 0.4 Ba 0.6 CuO 3-x . The X-ray powder diffraction pattern of the sample indicates almost an orthorhombic phase. The onset superconducting transition temperature T c (onset) and the transition width ΔT c are sensitive to the sintering temperature. The best superconducting properties are obtained when the sample is sintered at about 1000°C in oxygen flow; T c (onset)=91.2K, ΔT c =1.4K and the critical current density at 77K J c ≧60A/cm 2 .