PIEZOELECTRIC CERAMIC COMPOSITION FOR CERAMIC ACTUATOR AND PRODUCTION METHOD THEREOF

摘要

PURPOSE: Provided is a piezoelectric ceramic composition, which has excellent piezoelectric properties suitable to be used in a highly reliable piezoelectric component even at a temperature less than 1000 deg.C and reduces environmental pollution. CONSTITUTION: The piezoelectric ceramic composition is represented by the formula of: (Pb1-3a/2Ya)£(Ni1/3Nb2/3)x(TiyZr1-x-y)|O3 + b wt.% CuO, wherein x is ranged from 0.05 to 0.2, y is ranged from 0.4 to 0.55, a(the proportion of yttrium substituted for Pb) is ranged from 0 to 5, and b(the proportion of CuO as the additive) is ranged from 0 to 1, expressed by the atom% basis. The piezoelectric ceramic composition is produced by the method comprising the steps of: weighing PbO, ZrO2, TiO2, NiO, Nb2O5, Y2O3 and CuO ceramic powders according to a desired composition; wet mixing the powder; drying and firing the mixture; adding a small amount of CuO, wet milling the mixture and then molding; firing the molded product and polishing the both surfaces of the molded product; forming electrodes on the both surfaces of the polished product; and then polarizing the product having electrodes.