(Bi1/2Na1/2)TiO3-BaTiO3 System for Lead-Free Piezoelectric Ceramics
Abstract
One of the (Bi1/2Na1/2)TiO3 (BNT)-based solid solutions, Ba-modified bismuth sodium titanate, (Bi1/2Na1/2)1-xBaxTiO3 (BNBT), is studied for its dielectric and piezoelectric properties as a new group of lead-free piezoelectric ceramics. A rhombohedral (Fα)-tetragonal (Fβ) morphotropic phase boundary (MPB) is shown to exist at x{=}0.06∼ 0.07 by X-ray data, and dielectric and piezoelectric properties. BNBT ceramics with the MPB composition are superior as piezoelectric ceramics in high-frequency ultrasonic applications or as piezoelectric actuator materials because of a lower free permittivity, \varepsilon33T/\varepsilon0, and a high electromechanical coupling factor, kt or k33, along with high mechanical strength.
- Publication:
-
Japanese Journal of Applied Physics
- Pub Date:
- September 1991
- DOI:
- 10.1143/JJAP.30.2236
- Bibcode:
- 1991JaJAP..30.2236T
- Keywords:
-
- Barium Titanates;
- Bismuth Compounds;
- Mixed Oxides;
- Piezoelectric Ceramics;
- Sodium Compounds;
- Dielectrics;
- Electromechanics;
- Mechanical Properties;
- Phase Separation (Materials);
- Sintering;
- Temperature Dependence;
- Solid-State Physics