Ferroelectric properties of Bi0.5(Na0.8K0.2)0.5TiO3 ceramics

JAVIER CAMARGO; LEANDRO RAMAJO; FERNANDO RUBIO-MARCOS; MIRIAM CASTRO

Joao Pessoa

Congreso; ICE-2013; 2014

UNESP, USCAR

Lead titanate?zirconate piezoceramics are the most important and widely used materials for piezoe-lectric transducers, transformers and sensors. However, the toxicity of lead is a serious threat to human health and environment. Then, numerous studies on lead-free piezoelectric ceramics such as (K,Na)NbO3, BaTiO3-based, Bi-layered, bismuth sodium titanate and tung-sten bronze-type materials have been recently pub-lished. In this way, other piezoelectric compositions, such as Bi0.5Na0.5TiO3 (BNT), Bi0.5K0.5TiO3 (BKT), and the Bi0.5(Na0.8K0.2)0.5 TiO3 (BNKT) binary system have been studied due to their excellent piezoelectric and ferroelectric properties in the rhombohedric-tetragonal morphotropic border. In this paper, lead-free Bi0.5(Na0.8K0.2)0.5TiO3-based ceramics were prepared by the solid state reaction method. Results were discussed considering the effect of secondary phases on structure, microstructure, die-lectric and piezoelectric properties of these ceramics.