The electric field induced strain was studied in PLZT ferroelectric ceramic compositions near the tetragonal-rhombohedra1 phase boundary. The field induced strain was contributed by domain rotation, together with piezoelectric and electrostriction distortion. The electrostrictive nature of the induced strain increases with La content and Zr/Ti ratio, while the piezoelectric nature of the induced strain decreases with La content and Zr/Ti ratio. The domain rotation related strain is maximized at the morpotropic phase boundary (MPB). A longitudinal strain of 0.54% was obtained for a PLZT 5/56/44 ceramic composition under only 15 kv/cm field. The field induced strain was studied in 8/65/35 ceramics with different grain size. The large grain ceramics show larger field induced polarization and strain and more nearly square hysteresis loops than small grain ceramics. Charge controlled remanent strain was studied for 7.5/65/35 hot pressed ceramics. The remanent strainremanent polarization relation is found to be much more anhysteretic than the strain-electric field relation. The advantages of this ceramic system for ultrahigh strain compact actuator application is discussed.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics