Piezoelectric ceramic composition, especially for piezoelectric ceramic filters, oscillators and vibrators, is based on a low sintering temperature strontium-bismuth niobate-tungstate

摘要

A piezoelectric ceramic composition is based on a strontium-bismuth niobate-tungstate of specified composition. A novel piezoelectric ceramic composition contains a main component of formula: (a) SrBi2(Nb1-yWy)2O9, where y = greater than 0 to 0.3; (b) (Sr1-xM'x)Bi2(Nb1-yWy)2O9, where M' = a divalent metal other than Sr or a trivalent metal other than Bi, x = greater than 0 to 0.3 and y = greater than 0 to 0.3; or (c) (Sr1-xM2x/3)Bi2(Nb1-yWy)2O9, where M = a trivalent metal other than Bi, x = greater than 0 to 0.45 and y = greater than 0 to 0.3. An independent claim is also included for a piezoelectric ceramic device comprising electrodes (14a, 14b, 14c) and a piezoelectric ceramic (12) of the above composition.