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We report on the experimental investigation of a high-frequency (1 MHz-1.8 GHz) dielectric dispersion in unpoled and poled Pb(Zr,Ti)O-3 ceramics. Two overlapping loss peaks could be revealed in the dielectric spectrum. The linear dependence between the low ...
Configuration of domain walls in undoped and Fe+3-doped lead zirconate titanate (PZT) ceramics at the morphotropic phase boundary has been investigated by the transmission electron microscopy. The distance between domain walls in undoped PZT is on the orde ...
The mechanism of the giant unipolar strain recently observed in a lead-free piezoceramic, 0.92(Bi0.5Na0.5)TiO3-0.06BaTiO(3)-0.02(K0.5Na0.5)NbO3 [S.-T. Zhang, A. B. Kounga, E. Aulbach, H. Ehrenberg, and J. Rodel, Appl. Phys. Lett. 91, 112906 (2007) was inve ...
An evidence that the dielectric aging in the polydomain Pb(Zr0.45Ti0.55)O-3 thin films is controlled by progressive pinning of 180 degrees domain walls is presented. To provide such a conclusion, we use a general method, which is based on the study of the ...
This review discusses recent advances in understanding origins of large piezoelectric properties in some ferroelectric materials. In particular, it addresses the role of polarization rotation and monoclinic phases. It is suggested that the polarization rot ...
In bulk ferroelectric ceramics, extrinsic contributions associated with motion of domain walls and phase boundaries are a significant component of the measured dielectric and piezoelectric response. In thin films, the small grain sizes, substantial residua ...
A large body of work has been reported in the last 5 years on the development of lead-free piezoceramics in the quest to replace lead–zirconate–titanate (PZT) as the main material for electromechanical devices such as actuators, sensors, and transducers. I ...
We report Raman spectroscopy in all four phases of a (K0.5+delta Na0.5-delta)NbO3 (delta similar to 0.03) crystal and ((K0.5+delta Na0.5-delta)(1-x)Li-x)NbO3 for x=0.02 and 0.03. The phase transitions in the Li-free crystal are homogeneous and hysteretic, ...
The converse piezoelectric response of Pb(ZrxTi1−x)O3 ceramics is investigated as a function of material composition. The effects of the crystallographic phase and different dopants on piezoelectric nonlinearity are separately examined. For a linear depend ...
Research on lead-free piezoceramics has dramatically increased over the last years due to stringent legislation demanding to phase out current lead- containing piezoceramics. The use of electrostrictive materials for electric-field induced strain has been ...
