Piezoelectric ceramic composition and piezoelectric ceramic element using the same

Abstract

A piezoelectric ceramic composition includes a bismuth layered compound containing Sr, Bi, Nb and a metal element other than Bi having a valence of 3. The bismuth layered compound satisfies the relational expressions: 0.275<a/c<0.5; 0.9≦b/c≦1; 0<x/c≦0.175; and 0.5<(a+3x/2)/c≦0.7, where a, b, c and x represent the molar fractions of Sr, Bi, Nb, and the metal element other than Bi having a valence of 3, respectively. Thus, a piezoelectric ceramic composition mainly containing a bismuth layered compound whose bismuth content is equal to or less than the stoichiometric value and not substantially containing lead and which can be advantageously used for piezoelectric ceramic elements exhibiting a Qmax-factor sufficient for practical use can be achieved.

Dependencies are inferred from the claim text.