Study on the preparation of nbbt lead-free piezoceramics powders by hydrothermal method

(Na_0.5Bi_0.5)_0.94Ba_0.06TiO₃ (NBBT) powders are prepared by hydrothermal synthesis process. The effects of process conditions on the structure of NBBT are studied. In addition, effect of surface performance of NBBT powders is discussed with the amount of coupling agent increasing. The structure and property of the resulted powders were characterized by X-Ray diffraction (XRD). The granularity distribution and the surface morphology of the resulted films were studied by laser diffraction-based particle size analyzer and scanning electron micrograph (SEM).The results showed that that pure NBBT powders can be obtained when the powders is calcined at the 180 C for 48 hours. And appropriately adding coupling agent can strengthen the density of powders. The impurities of BaTiO₃ show an earlier increase and later decrease with the amount of coupling agent increasing.