PIEZOELECTRIC CERAMIC COMPOSITION AND PIEZOELECTRIC DEVICE

摘要

Disclosed is a piezoelectric ceramic composition having a main component represented by the following general formula:[(Pb<SUB>1-x-y</SUB>Ca<SUB>x</SUB>Sr<SUB>y</SUB>){Ti<SUB>1-z</SUB>(Ni<SUB>1/3</SUB>Nb<SUB>2/3</SUB>)<SUB>z</SUB>}O<SUB>3</SUB>], wherein x, y and z satisfy 0 = x = 0.2 (preferably, 0 = x = 0.15), 0 = y = 0.2 (preferably, 0 = y < 0.1), 0.05 = x + y = 0.2 and 0.02 = z = 0.1. The piezoelectric ceramic composition may preferably contain an Mn component in an amount of not more than 1.0 part by weight (excluding 0 and preferably in an amount of 0.05-1.0 part by weight) in terms of MnCO<SUB>3</SUB> per 100 parts by weight of the main component. Also disclosed is a piezoelectric device comprising a piezoelectric ceramic element (1) which is composed of the piezoelectric ceramic composition. This piezoelectric device can be fired at a low temperature such as 1100°C, while having a high Curie point Tc which enables to stand a solder reflow process. The piezoelectric device exhibits good piezoelectric characteristics.