SYNTHESIS OF NEARLY SINGLE-PHASE (HG, PB)BA2CA2CU3O8+DELTA SUPERCONDUCTORS

An ''encapsulation and single-firing'' technique was successfully util ized for the preparation of nearly single-phase polycrystalline sample s of (Hg1-xPbx)Ba2Ca2Cu3O8+delta [(Hg, Pb)-1223] with various Pb conte nts, 0 less than or equal to x less than or equal to 0.3. All the as-s intered samples with x less than or equal to 0.3 exhibited bulk superc onductivity at similar to 133K. After post-annealing in flowing O-2 ga s, T-c(mag) of (Hg, Pb)-1223 decreased with increasing x, e. g., T-c(m ag) similar to 124K for the sample with x=0.3. Thus, oxygenated (Hg, P b)-1223 samples were likely to be in the overdoped region.