Abstract: Disclosed is a piezoelectric ceramic composition comprising a PZT piezoelectric composition, a B-site of which is substituted with a certain material, and chromium oxide, and a piezoelectric device using the piezoelectric ceramic composition. The piezoelectric ceramic composition has good heat resistance and frequency stability, and reduces a leakage current. There is provided the piezoelectric ceramic composition comprising a main component expressed by Pb[(Co1/2W1/2)xTi1-x-yZry]O3 (wherein, 0.001≦x≦0.04, and 0.35≦y≦0.55), Cr2O3 in an amount of 0.01 to 2 wt %, MnO2 in an amount of 0.1 to 0.5 wt %, and an additive in an amount of 0.01 to 2.0 wt %, based on the total weight of the piezoelectric ceramic composition, in which the additive is selected from the group consisting of CoO, MgO, ZnO, Al2O3, Fe2O3, Sb2O3, SnO2, CeO2, Nb2O5, V2O5 and WO3, and mixtures thereof.

Abstract: Disclosed is a method for preparing barium titanate powder by oxalate synthesis, whereby barium titanate powder or doped barium titanate powder with excellent powder properties can be produced at high efficiency and with economic benefit. An aqueous solution containing barium chloride and titanium chloride or further containing at least one dopant serving as a donor or acceptor is mixed with an aqueous oxalic acid solution to afford barium titanyl oxalate (BTO) or doped-BTO as a precipitate which is then aged, washed, and dried, followed by primary calcination and pulverization and secondary calcination and pulverization.

Abstract: The present invention provides a piezoelectric ceramic composition having the formula: {[Pb(1−1.5x)±(0˜0.2)Lax][Ti(1−y−z)MnyCUz]O3} which meets the requirements: 0.02<x<0.14, 0.01≦y<0.04, and 0.002≦z≦0.008.

Abstract: A dielectric ceramic composition of high dielectric constant and low dielectric loss, which can be co-fired with Ag electrodes, is provided for use in various parts of electric and electronic appliances.

Abstract: A dielectric ceramic composition of high dielectric constant and low dielectric loss, which can be co-fired with Ag electrodes, is provided for use in various parts of electric and electronic appliances.

Abstract: A dielectric ceramic composition of high dielectric constant and low dielectric loss, which can be co-fired with Ag electrodes, is provided for use in various parts of electric and electronic appliances.

Abstract: The present invention discloses a method for preparing a barium titanate and barium titanate based powder by an oxalate process. The method is carried out in the following manner: An aqueous mixture solution containing barium chloride and titanium chloride is added into an aqueous oxalic acid solution, so that barium titanyl oxalate would be precipitated. Then the precipitates are aged, washed and filtered. The filtered barium titanyl oxalate precipitates are crushed, and dried. Then a thermal decomposition is carried out to obtain a agglomerated barium titanate powder, and this is crushed again to obtain the final barium titanate powder. In order to obtain barium titanate based powder such as Ba(Ti1−zZrz)O3, (Ba1−xCax)(Ti1−zZrz)O3, and (Ba1−x−yCaxSry)(Ti1−zZrz)O3, the desired elements (Ca, Sr, Zr and so on) are added to barium titanyl oxalate when crushed before thermal decomposition step.