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Superconducting Bi(Pb)-Sr-Ca-Cu-O powders were prepared by the emulsion-drying method The powders consisting of the low-Tc phase (Bi(Pb)2Sr2Ca1Cu2Oy) and small amount of Ca2PbO4 were prepared by calcining under low oxygen partial pressure at 750°, 800°C. These calcined powders were used to prepare thick films on single-crystal MgO(100) substrates using a screen-printing technique to study the effect of the calcinations temperature and annealing procedure on the high-Tc phase (Bi(Pb)2Sr2Ca2Cu3Oy)formation. The formation of high-Tc phase was observed to be dependent on the calcinations conditions. The high-Tc phase formed very quickly (sintering at 840°C for 4 h), and the best films showed a sharp superconducting transition at about 105 K.

The sintering temperature of 0.95(Na0.5K0.5)NbO3–0.05BaTiO3 (NKN–BT) ceramics needs to be decreased below 1000°C to prevent Na2O evaporation, which can cause difficulties in poling and may eventually degrade their piezoelectric properties. NKN–BT ceramics containing CuO were well sintered at 950°C with grain growth. Poling was easy for all specimens. Densification and grain growth were explained by the formation of a liquid phase. The addition of CuO improved the piezoelectric properties by increasing the grain size and density. High piezoelectric properties of d33=230 pC/N, kp=37%, and ɛ3T/ɛ0=1150 were obtained from the specimen containing 1.0 mol% of CuO synthesized by the conventional solid-state method.