Zhang, Shan-Tao ; Kounga, Alain Brice ; Aulbach, Emil ; Granzow, Torsten ; Jo, Wook ; Kleebe, Hans-Joachim ; Rödel, Jürgen (2008)
Lead-free piezoceramics with giant strain in the system Bi0.5Na0.5TiO3–BaTiO3–K0.5Na0.5NbO3. I. Structure and room temperature properties.
In: Journal of Applied Physics, 103 (3)
doi: 10.1063/1.2838472
Article

Abstract

Lead-free piezoelectric ceramics, (1−x−y)Bi0.5Na0.5TiO3–xBaTiO3–yK0.5Na0.5NbO3 (0.05 <= x <= 0.07 and 0.01 <= y <= 0.03), have been synthesized by a conventional solid state sintering method. The room temperature ferroelectric and piezoelectric properties of these ceramics were studied. Based on the measured properties, the ceramics were categorized into two groups: group I compositions having dominant ferroelectric order and group II compositions displaying mixed ferroelectric and antiferroelectric properties at room temperature. A composition from group II near the boundary between these two groups exhibited a strain as large as ∼ 0.45% at an electric field of 8 kV/mm. Polarization in this composition was not stable in that the piezoelectric coefficient d33 at zero electric field was only about 30 pm/V. The converse piezoelectric response becomes weaker when the composition deviated from the boundary between the groups toward either the ferroelectric or antiferroelectric compositions. These results were rationalized based on a field induced antiferroelectric-ferroelectric phase transition.

Send an inquiry

Show editorial Details