Piezoelectric and Dielectric Characteristics of (Na,K)(Nb,Sb)O₃ Ceramics Doped with CoO

Abstract

In this study, in order to develop lead free piezoelectric ceramics which have excellent temperature stability and high sinteribility for low loss multilayer piezoelectric actuator application, (Na,K)(Nb,Sb)O₃ ceramics were fabricated and their piezoelectric and dielectric properties were investigated as a function of the amount of CoO addition. CoO addition improved sinterability, electromechanical coupling factor k_p, piezoelectric constant d₃₃ and dielectric constant ϵ_r of the composition ceramics. At the 0.3 wt% CoO added composition, density, k_p, d₃₃, ϵ_r and phase transition temperature showed the optimum values of 4.30 [g/cm³], 0.41, 211 [pC/N], 751 and 155°C, respectively, for low loss multilayer piezoelectric actuator application.

Keywords:

• Low loss multilayer piezoelectric actuator
• low temperature sintering
• mechanical quality factor
• electromechanical coupling factor