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Defects play a critical role in the dynamic fragmentation process of structural ceramics. Cracks initiate at seemingly random locations, propagate and coalesce to form fragments. The process is accompanied by stress release waves, whose influence is diffic ...
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 ...
Piezoelectric response nonlinearity is approached using the Preisach description of hysteretic systems as collection of distributed bistable units. The Preisach model and its recent physical interpretation in terms of moving domain wall in a stochastically ...
Thickness mode resonances in commercial piezoelectric ceramics have been characterised as a function of frequency by two methods. The first is based on a fit on the electrical impedance for the fundamental and the overtones. This method has been applied to ...
The effect of boundary conditions (e.g., type of metal contacts) and sample geometry (e.g., sample aspect ratio) on measurements of direct longitudinal d(33) coefficient in piezoelectric ceramics is studied by direct quasistatic method. We show that at sma ...
Stress induced ferroelastic switching may represent an efficient toughening mechanism in piezoelectric-ferroelectric ceramics. During the crack propagation, the high tensional stresses at the crack tip can be partially released by the reorientation of 90 d ...
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Hysteretic and nonlinear dielectric behaviour in ferroelectric ceramics has been of interest since 1950s, when these materials found application in various electronic devices. Presently, these phenomena concern with important areas of science, technology a ...
The piezoelectric properties of 31-mode resonators of lead zirconate titanate ceramics under hydrostatic pressure from 0.1 to 325MPa were evaluated by a fitting method, in which mechanical loss was taken into account. Our results based on the fitting metho ...
Radio frequency (RF) filters based on bulk acoustic wave resonances in piezoelectric thin films have become indispensable components in mobile communications. The currently used material, AlN, exhibits many excellent properties for this purpose. However, i ...
Pb(Zr,Ti)O3 ceramics with homogenous, anisotropic porosity were manufactured and the influence of the anisotropic porosity on the dielectric and piezoelectric properties was studied. Image analysis allowed the quantification of the preferential orientation ...
