Ceramics-Silikáty 58 (1) 50-55 (2014)

FABRICATION AND MECHANICAL PROPERTIES OF Na_0.5Bi_0.5TiO₃–BaTiO₃ LEAD-FREE PIEZOELECTRIC CERAMICS

Piezoelectric ceramics with 0.94Na_0.5Bi_0.5TO₃–0.06BaTiO₃ compositions were fabricated by solid state mixed oxide method and sintered at different temperatures varying from 1050°C to 1150°C to obtain dense ceramics. Phase analysis using X-ray diffraction showed tetragonal perovskite structure of Na_0.5Bi_0.5TO₃ with no BaTiO₃ peak detected. The SEM observation revealed that the crystal grain size of the piezoelectric ceramics is on the nano-size dimensions under all the sintering temperature. The study on the compressive mechanical characteristics showed that the compressive strength of the 0.94Na_0.5Bi_0.5TO₃–0.06BaTiO₃ piezoelectric ceramics increases with the rise of sintering temperature and sintering time. The change behavior of the compressive strength with the rise of cold pressure presents increasing firstly and then decreases.

Keywords: Na_0.5Bi_0.5TiO₃–BaTiO₃, Lead free piezoelectric ceramics, Microstructure, Compressive strength