Piezoelectric Properties of KNbO3 Ceramics Prepared by Ordinary Sintering

Abstract

Potassium niobate, KNbO 3 (KN), ceramics were prepared by the modified conventional ceramic fabrication process to characterize their piezoelectric properties. KN single crystal has high electromechanical coupling factor k 33 = 0.66. On the other hand, the difficulty in obtaining dense and nondeliquescent KN ceramics by conventional methods limits our knowledge of the piezoelectricity of this ceramic. The KN ceramics showed the piezoelectric properties such as the electromechanical coupling factor k 33 , the piezoelectric constant, d 33 , and the mechanical quality factor, Q m, were 0.49, 91.7 pC/N and 325, respectively. This sample was poled at a DC electric field of 5 kV/mm at 150°C.