This article presents the results of a parameters study on a piezoelectric flexible transducer of a beam type. The analysis was performed by the finite element method using the ANSYS Multiphysics software package. It is shown that there are optimal parameters ratios of the structural elements of the transducer under study for which it is the most effective
Keywords: bending-type piezoelectric transducer, piezoelectric element, elastic plate, resonance frequency, conversion coefficient, Electromechanical coupling coefficient
Piezoceramic frames made of PKP-12 material with porosity up to 50% are made. The effect of the total, open and closed porosity on the properties of porous piezoelements on a given piezoelectric material is studied. Hydrostatic tests of porous piezoelements have been performed to determine the pressure at which irreversible changes occur.
Keywords: piezoceramics, PKP-12, piezocomposites, porous piezoceramics, piezoelectric materials, ferroelectrics, PZT, hydroacoustics, hydrophone
The loops of the dielectric hysteresis of a soft ceramics based on PZT with Curie temperature TC=210℃ are investigated. The studies were carried out at a frequency of 50 Hz in two modes. In the first of them, the field was switched on by 0.07 seconds, in the second - it operated continuously. The amplitude of the field E_m varied from 2.5 to 25 kV / cm and switched stepwise with an interval of 15 minutes. The coercive field EC and the switchable polarization P_m were determined. The switching polarity in the saturation region turns out to be no more, in contrast to BaTiO3 and other materials, but less than the corresponding values obtained with short-term switching.
Keywords: piezoceramics, piezoelectric material, hot pressing, dielectric hysteresis
Piezoceramics phases of (1-х)PbTiO3-xPbZrO3 is the basis of most high-performance piezoelectric materials. Electrophysical and mechanical properties of these materials can be varied over a wide range by varying the composition and by processing methods: the methods and modes of sintering conditions polarization. Topical to study the influence on the properties of PZT materials processing methods at the stages of manufacturing piezoelectric samples. In the role model of the object has been selected multicomponent system PbTiO3-PbZrO3-PbNb2/3Zn1/3O3-PbW1/2Mg1/2O3-PbSb2/3Mn1/3O3. Samples of piezoelectric elements for the study were obtained in two ways: in the first case, the sintering samples was carried out by the usual ceramic technology, and in the second by hot pressing. The grain structure was formed in both cases in the presence of the glass phase, the quantity of which decreases with increasing temperature, while in the first case, an increase in the velocity of the secondary recrystallization, and in the second of its suppression. It was found that regardless of the technology of the samples εT33/ε0, d33 and VЕ1 at high temperatures, due to the increase of grain and coercive field, which complicates the process of polarization. Maximum values εT33/ε0, d33 and VЕ1 samples prepared by hot pressing at 10 - 15% higher than if received by conventional ceramic technology.
Keywords: Piezoelectric ceramics, doping, combination, pezophase, piezomaterial
The problem of manufacturing technology heterostructures pezofaza - metal considered in the article. Complexity consists in the fact that during the removal of the polymer in the system at low temperatures are formed porous layers, formed powders separated metal layers, having island macrostructure. One way to solve the problem - reducing the firing temperature heterostructures. Proposed to decrease the sintering temperature by using of functionally active glass-phases. Reducing the sintering temperature of products also allows to replace platinum electrodes inexpensive silver-based alloys. Obtained by solid state reaction method of piezoceramic material has a low sintering temperature (980 ° C) and high electrical parameters. Found that not only the proportion of the vitreous mass, but also their qualitative influence on the properties of piezomaterials
Keywords: heterostructure glass phase, the sintering temperature, porosity, ferroelectric phase
Laboratory technology was developed to fabricate flexible piezocomposites with ferroelectric phase - polymers having signal reception factorv • gv 5000 • 10-15 m2 / N. The values of the given coefficient were achieved by switching from a probabilistic (spontaneous) percolation to a correlated one in the process of forming material. This made the production of 0-1–3 piezocomposites, in which a part of piezophase has 0 connectivity, and the other part – 1 connectivity possible. To improve the efficiency of piezocomposite polarization before their manufacturing the surface of piezophase particles, which were obtained by the partial destruction of the porous frameworks, was treated with coupling agent, which did not only improve the polymer adhesion to piezophase, but also allowed the removal of water from the particle surface. The latter effect reduced the value of interfacial conductivity, i.e. prevented the voltage drop of the polarizing field. Matching of polymer conductivity and piezoceramic particles by determining the optimal polarization temperature was carried out as well.
Keywords: piezocomposites, percolation, connectivity, electrophysical properties
It was investigated the influence several additives and process parameters on the properties of piezoelectric ceramics based on PZT phase systems. It was shown that the use of the substitution of Pb2+ ions on the Bi3+, and Ti4+ ions, and Zr4+ to Fe3+ and Mn4+, as well as the method of "chemical assembly «allows to obtain increase the Curie temperature of ceramic samples of 50 - 170°C. The theoretical aspects of this area of research have been discussed in this article.
Keywords: ferroelectric phase, Curie temperature, ceramics, precursors, perovskite, a solid-state method, a method of «chemical assemblage