(Pb, Ca) ((Co1/2W1/2), Ti)O3 Piezoelectric Ceramics and Their Applications

Abstract
Piezoelectric properties in (Pb, Me) ((Co1/2W1/2), Ti)O3 ceramics (Me=Ba, Sr or Ca) containing small amounts of MnO and NiO have been investigated. These ceramics are characterized by high apparent density, small dielectric constant (about 200) and facility in poling procedure. Among the ceramics added with the alkaline earth metals, the Ca-modified ceramics show markedly excellent performance–large longitudinal coupling factors k 33=0.54, k t=0.52, small transverse coupling factors k 31=0.027, K p=0.043 and small temperature coefficients less than 5 ppm/°C of frequency constants for radial and thickness vibration modes.