The Piezoelectric Properties of La2O3 Doped (Bi1/2Na1/2)TiO3-(Bi1/2K1/2)TiO3 Ceramics

• Published in: Ferroelectrics Vol. 358; no. 1; pp. 134 - 138
• Main Authors: Yoshii, K., Hiruma, Y., Suzuki, M., Nagata, H., Takenaka, T.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: London Taylor & Francis Group 01.01.2007; Taylor and Francis
• Subjects: bismuth potassium titanate; bismuth sodium titanate; Condensed matter: electronic structure, electrical, magnetic, and optical properties; depolarization temperature; dielectric properties; Dielectric properties of solids and liquids; Dielectric, piezoelectric, ferroelectric and antiferroelectric materials; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Exact sciences and technology; lanthanum doped; Lead-free; Niobates, titanates, tantalates, pzt ceramics, etc; Permittivity (dielectric function); Physics; piezoelectric properties; Piezoelectricity and electromechanical effects; Actuators; Dielectric properties; Doping; bismuth sodium titanate; Bismuth Titanates; Electromechanical coupling; bismuth potassium titanate; Lead-free; Depolarization; Potassium Titanates; depolarization temperature; Solid solutions; Rare earths; Sodium Titanates; Piezoelectricity; Chemical composition; piezoelectric properties; Permittivity; lanthanum doped
• ISSN: 0015-0193; 1563-5112
• DOI: 10.1080/00150190701536978

The piezoelectric properties of a solid solution, x(Bi 1/2 Na 1/2 )TiO 3 -(1-x)(Bi 1/2 K 1/2 ) TiO 3 + La 2 O 3 y wt% [BNKTx + La 2 O 3 y wt%; x = 0.50, 0.70, y = 0-0.6] were investigated, focusing on piezoelectric constant, d 33 , and depolarization temperature, T d . The dielectric constant increased with increasing La 2 O 3 content (y). The highest electromechanical coupling factor, k 33 (0.493) and the highest d 33 (153 pC/N) was obtained in BNKT0.70 + La 2 O 3 0.2wt%. The T d of BNKT0.70 + La 2 O 3 y wt% was almost the same with y = 0-0.3 at 210-220°C and decreased with y ≥ q 0.4. BNKT0.70 + La 2 O 3 0.2 wt% (d 33 = 153 pC/N and T d = 219°C) is a good candidate for practical use in actuators.