Large piezoelectric strains from polarization graded ferroelectrics

• Published in: Applied physics letters Vol. 89; no. 14; pp. 142913 - 142913-3
• Main Authors: Zhong, S., Ban, Z.-G., Alpay, S. P., Mantese, J. V.
• Format: Journal Article
• Language: English
• Published: American Institute of Physics 02-10-2006
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.2358963

The potential applications of polarization graded ferroelectrics as high performance sensors and actuators are theoretically investigated. A static bending can be expected in polarization graded ferroelectric plates, forming a vertical displacement. This is due to the built-in strain gradient that arises from the grading of the composition and concomitantly, the spontaneous self-strain. Numerical results of two compositionally graded ferroelectrics,
Ba
Ti
O
3
-
Ba
1
−
x
Sr
x
Ti
O
3
and
Pb
Ti
O
3
-
Pb
1
−
x
Zr
x
Ti
O
3
, show a high dynamic response of the displacement under an external electric field, yielding as much as
∼
23
%
strain at
50
kV
∕
cm
in
Pb
Ti
O
3
-
Pb
0.6
Zr
0.4
Ti
O
3
, which is comparable to large displacement actuators formed from ceramic/ceramic and ceramic/metal multilayer mesomaterials.