Lead-free Piezoelectrics Based on Alkaline Niobates: Synthesis, Sintering and Microstructure

Barbara Malič, Andreja Benčan, Tadej Rojac and Marija Kosec

Jožef Stefan Institute, 1000 Ljubljana, Slovenia
* Corresponding author: E-mail: barbara.malic@ijs.si

Abstract
The objective of this review is to focus on the processing of ceramics based on sodium potassium niobate (K_0.5Na_0.5NbO₃) as promising candidates for lead-free piezoelectrics. In the first part the review addresses the synthesis of the perovskite solid solution as well as the issue of chemical homogeneity for pure and chemically modified K_0.5Na_0.5NbO₃. The second part covers the sintering and typically encountered bimodal microstructure of K_0.5Na_0.5NbO₃, possible methods of controlling the grain growth and template-assisted grain growth resulting in alkaline niobate single crystals.

Keywords: (K,Na)NbO₃, synthesis, sintering, microstructure