Piezoelectric Properties of Pure and Mn-doped Potassium Niobate Ferroelectric Ceramics

Potassium niobate, KNbO 3 (KN), ceramics doped with manganese (Mn) were prepared by the conventional ceramic fabrication process to characterize their electrical properties. The difficulty in obtaining dense ceramics by conventional methods limits our knowledge of the piezoelectricity of this ceramic. In this paper, an optimized process for obtaining dense (over 95%) and nondeliquescent KN ceramics is described. Dielectric and piezoelectric data are also presented. In particular, fine piezoelectric properties were obtained in Mn-doped KN ceramics (KN+MnCO 3 x wt %: KN–Mn x ), and the highest electromechanical coupling factor, k 33 was 50.7% for KN–Mn0.2.