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1

Acoustic Matching Characteristics of Annular Piezoelectric Ultrasonic Sensor

Li Haoran, Hu Yan, Li Laibo, Xu Dongyu

Archives of Acoustics

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2022

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Vol. 47, No. 2

275--284

EN

Using intelligent materials and sensors to monitor the safety of concrete structures is a hot topic in the field of civil engineering. In order to realize the omni-directional monitoring of concrete structural damage, the authors of this paper designed and fabricated an embedded annular piezoelectric ultrasonic sensor using the annular piezoelectric lead zirconate titanate (PZT) ceramic as a sensing element and epoxy resin as the matching and the backing layers. The influence of different matching and backing layers thickness on the acoustic characteristic parameters of the sensor were studied. The results show that the resonant frequency corresponding to the axial mode of annular piezoelectric ceramics moves toward the high frequency direction with the decrease of the height of piezoelectric ceramics, and the radial vibration mode increases as well as the impedance peak. With the thickness of the backing layer increases from 1 mm to 2 mm, the radial resolution of the annular piezoelectric ultrasonic sensor is enhanced, the pulse width is reduced by 39% comparing with the sensors which backing layer is 1 mm, and the head wave amplitude and −3 dB bandwidth are increased by 61% and 66%, respectively. When the matching layer thickness is 3 mm, the sensor has the highest amplitude response of 269 mV and higher sensitivity.

2

Synthesis of barium titanate piezoelectric ceramics for multilayer actuators (MLAs)

Biglar M., Stachowicz F., Trzepieciński T., Gromada M.

Acta Mechanica et Automatica

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2017

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Vol. 11, no. 4

275--279

EN

In this paper the characteristics of BaTiO3 ceramics synthesized by solid state method is presented. In order to receive the monophase ceramics the double activation and calcination were applied. A spray drier was used to granulate the powder of BaTiO3. Isostatic and uniaxial pressing were applied to manufacture the barium titanate pellets. The properties of fabricated BaTiO3 ceramics were determined at different stages of production. After the sintering phase, the hardness, the bending strength, the fracture toughness, and the coefficient of thermal expansion of barium titanate sinter were estimated. The BaTiO3 powder is characterized by spherical grains and the average size of 0.5 μm. The small value of the specific surface area of granulate ensured good properties of material mouldability and finally allowed to receive sinters of high density

3

Własności piezoelektryczne włókien ceramicznych

Kozielski L.

Materiały Ceramiczne

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2016

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T. 68, nr 1

44--48

PL

Ceramiczne materiały piezoelektryczne można otrzymywać w różnych postaciach i formach, zaczynając od tradycyjnej ceramiki objętościowej i cienkich oraz grubych warstw ceramicznych, a kończąc na formie włókien ceramicznych czy też praktycznie dowolnych kształtach, związanych z nowoczesnymi metodami wytwarzania wykorzystującymi drukarki 3D. Włókna piezoelektryczne wykazują wiele zalet w stosunku do objętościowej ceramiki tego samego typu. Można wśród nich wyróżnić lepszą anizotropię właściwości, elastyczność niemożliwą do osiągnięcia w ceramice objętościowej oraz większą wytrzymałość mechaniczną. Jednak metody, jakość składników wyjściowych oraz warunki wytwarzania tego typu włókien piezoelektrycznych dalej pozostają ogromnym obszarem badań i poszukiwań. Celami przedstawianego eksperymentu było wytworzenie piezoelektrycznych włókien metodą ekstruzji i zbadanie podstawowych parametrów materiałowych, elektrycznych i piezoelektrycznych oraz dokonanie analizy porównawczej właściwości w stosunku do komercyjnej ceramiki objętościowej.

EN

Ceramic piezoelectric materials can be prepared in various forms and shapes, starting from traditional bulk volumetric ceramics, and thin or thick ceramic layers finally ending in the form of ceramic fibres or even virtually any shape which is associated with novel production methods taking advantage of 3D printers. Piezoelectric fibres have a number of advantages compared to volumetric ceramics of the same type. Among them are improved anisotropy of properties, impossible to achieve in bulk ceramics, flexibility and associated with this greater mechanical strength. However, the methods, the quality of the starting components and the conditions for preparing this type of piezoelectric fibres still remain a vast area of research and investigations in order to effect optimum electrical and electromechanical properties of the final material. Objects of the experiment were to produce piezoelectric fibres by the extrusion method, examine electrical and piezoelectrical parameters, and comparative analysis with commercial bulk ceramics properties.

4

Materiały piezoelektryczne wytwarzane w Instytucie Metali Nieżelaznych w Gliwicach

Staszewski M., Czepelak M., Kamińska M., Ślusarek A., Lis M., Osadnik M., Bilewska K.

Rudy i Metale Nieżelazne Recykling

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2015

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R. 60, nr 3

127--135

PL

Opracowano procedury wytwarzania materiałów piezoelektrycznych przeznaczone do zastosowania w Instytucie Metali Nieżelaznych w Gliwicach opierając się na posiadanej bazie sprzętowej. Otrzymane materiały to seria spieków na osnowie perowskitu Pb(Zr,Ti)O3 (PZT), które po naniesieniu elektrod i spolaryzowaniu przetestowano w charakterze transformatorów w elektronicznym układzie pomiarowym. Stwierdzono, że materiały wykonane według proponowanych procedur cechują się zarówno właściwymi parametrami strukturalnymi i fizycznymi, jak też dobrymi właściwościami użytkowymi, w tym wysoką sprawnością. Mogą one zatem służyć do wytwarzania urządzeń elektronicznych, takich jak transformatory, przetwornice elektryczne, rezonatory itp.

EN

Procedures for manufacturing of piezoelectric materials, applicable in the Institute of Non-ferrous Metals in Gliwice with the use of installed equipment, are elaborated. Manufactured materials are the series of sinters based on Pb(Zr,Ti)O3 perovskite (PZT), which after application of electrodes and after polarization are tested as transformers in the electronic measuring system. It has been found that the materials made according to the proposed procedures, have the appropriate structural and physical parameters as well as good utility properties, including their high efficiency. Therefore, they may be used for production of electronic devices such as transformers, electric converters, resonators etc.

5

Wytwarzanie elektrooptycznych włókien PLZT metodą termo-plastycznego wytłaczania

Kozielski L., Adamska A.

Materiały Ceramiczne

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2010

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T. 62, nr 1

42-45

PL

Cyrkonian tytanian ołowiu domieszkowany lantanem (PLZT) jest materiałem, który cechuje wiele interesujących właściwości, wynikających z odpowiednio dobranych proporcji bazowego PZT i ilości wprowadzonego doń lantanu. Składy ferroelektryczne, oprócz właściwości piezoelektrycznych, może charakteryzować wysoka przeświecalność, pożądany efekt elektrooptyczny oraz duża szybkość odpowiedzi. Materiały typu PLZT można otrzymywać w różnych postaciach np. włókien, ceramiki objętościowej czy warstw ceramicznych. Włókna piezoelektryczne wykazują wiele zalet w porównaniu do objętościowej ceramiki tego samego typu. Wśród nich można wyróżnić lepszą anizotropię właściwości, doskonałą elastyczność oraz większą wytrzymałość. Jednak metody, jakość składników wyjściowych oraz warunki wytwarzania tego typu włókien dalej pozostają ogromnym obszarem badań i poszukiwań, aby w efekcie końcowy materiał posiadał odpowiednią jakość i parametry. Celem niniejszej pracy było wytworzenie elektrooptycznych włókien PLZT metodą termoplastycznego wytłaczania i zbadanie, w funkcji parametrów spiekania, podstawowych właściwości fizycznych, takich jak gęstość, porowatość i mikrostruktura otrzymanych włókien ceramicznych.

EN

Lanthanum-modified lead zirconate titanate (PLZT) ceramics are known to exhibit a range of interesting electro-optical properties. The advantages of PLZT ceramics include high optical transparency, desirable electrooptic properties, and fast response. Piezoelectric fibers present many advantages comparing to conventional piezoelectric bulk materials ie. higher anisotropy, excellent flexibility and higher strength, but processing methods and conditions of manufacturing are still actively studied because they affect significantly the final fibres properties. The aim of this study was to develop PLZT powder for the production of transparent or translucent thin fibers. The influence of different sintering parameters on the resultant microstructure and phase composition of the fibres was checked. The main goal of the experiments was to determine a sintering atmosphere suitable to achieve proper density, porosity and microstructure of the fibres.

6

Crack arrest saturation model under combined electrical and mechanical loadings

Bhargava R. R., Setia A.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 37, nr 2

544-548

EN

Purpose: The investigation aims at proposing a model for cracked piezoelectric strip which is capable to arrest the crack. Design/methodology/approach: Under the combined effect of electrical and mechanical loadings applied at the edges of the strip, the developed saturation zone is produced at each tip of the crack. To arrest further opening of the crack, the rims of the developed saturation zones are subjected to in-plane cohesive, normal uniform constant saturation point electrical displacement. The problem is solved using Fourier integral transform method which reduces the problem to the solution of Fredholm integral equation of the second kind. This integral equation in turn is solved numerically. Findings: The expressions are derived for different intensity factors and energy release rate. A qualitative analysis of the parameters affecting the arrest of opening of the crack and fatigue crack growth with respect to strip thickness and material constants are presented graphically. Research limitations/implications: The investigations are carried out by considering the material electrical brittle. Consequently, the zones protrude along the straight lines ahead of the crack tips. And further, the small scale electrical yielding conditions are used. Practical implications: Piezoelectric materials are widely getting used nowadays, even in day to day life like piezoelectric cigarette lighter, children toys etc. And, its advance used in technology like transducers, actuators has been already in progress. So, the aspect of cracking of piezoelectric materials are of great practical importance. Originality/value: The piezoelectric material under the combined effect of electrical and mechanical loadings gives the assessment of electrical displacement which is required to arrest the crack. The various useful interpretations are also drawn from the graphs.

7

Domain wall motion effect in piezoelectric ceramics

Bartkowska J., Bluszcz J., Zachariasz R., Ilczuk J., Bruś B.

Molecular and Quantum Acoustics

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2008

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Vol. 29

7-10

EN

The internal friction (Q-1) in multiple-components ceramics PZT type was measured as a function of temperature from 300 to 600 K. An internal friction peak (P2) appears a few dozen degrees below Curie temperature (TC). The P2 peak of internal friction is found to be associated with the viscous-elastic mobility of domain walls. The internal friction due to the viscous-elastic mobility of domain walls was calculated and compared with the experimental data.

8

Modified strip saturation model for a cracked piezoelectric strip

Bhargava R., Setia A.

Archives of Materials Science and Engineering

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2008

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Vol. 30, nr 1

33-36

EN

Purpose: The investigations aim to propose a model for arresting an electrical opening of a crack which weakens a narrow, poled and infinite piezoelectric strip. The edges of the strip are subjected to uniform, constant anti-plane stresses and in-plane electrical displacements. Design/methodology/approach: The loads applied at the edges of the strip open the crack in a self-similar fashion. Consequently at each tip of the crack a saturation zone protrudes. To stop the crack from further opening the rims of developed saturation zones are subjected to normal, cohesive linearly varying saturation limit electric displacement. The edges of the strip are subjected to anti-plane deformation and in-plane electrical displacement. Fourier integral transform method employed reduces the problem to the solution of a Fredholm integral equation of second kind. Findings: The electrical displacement, stress intensity factor, the saturation zone length, crack opening displacement and crack growth rate have been calculated. The results obtained presented graphically, analysed and concluded. Research limitations/implications: The ceramic used for strip is being assumed to be electrically more brittle. The investigations are carried at this level in the present paper. Also the small scale electrical yielding is considered. Consequently the developed saturation zone is proposed to lie in a line segment ahead of crack. Practical implications: Piezoelectric ceramics being widely used as transducers. Their wide utility has prompted to study many attires of such ceramic and one such attire is fracture mechanics of these ceramics. Originality/value: The paper gives an assessment of the electrical load necessary to arrest the electrical crack opening. The investigations are useful to smart material design technology where sensors and actuators are manufactured.

9

Influence of the Chemical Composition on the Physical Properties of Pzt-Type Piezoceramic Transducers.

Surowiak Z., Czekaj D., Fesenko E., Razumovskaya O., Reznichenko L., Zakharchenko I.

Molecular and Quantum Acoustics

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2003

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Vol. 24

183-209

EN

Result if investigations on influence of lead deficiency on the crystalline structure of PZT-type ceramic piezoelectric materials is presented. The solid solution of (x)PbTiO3-(1-x-y)PbZrO3-(y)SigmaPb(B'1-alfaB"alfa)O3, exhibiting the perovskite-type structure, condtitutes the basis of such materials. The lead deficiency was originated by a thermal treatment. Investigations on influence of lead deficiency on the crystalline structure of PZT-type ceramics have been performed for solid solutions exhibiting the chemical compositions corresponding to the tetragonal or rhombohedral boundary of the morphotropic region (PCR-1, PCR-8: "Piezoelectric Ceramics of Rostov") and to tetragonal phase region compositions (ceramics of Pb(Zr0.39Ti0.59W0.01Cd0.01)O3). It has been found that the deficiency in lead causes a change of the point group or a change of the space group of the perovskite phase crystalline structure of PZT. The solid solutions on the basis of Pb(Zr,Ti)O3 partly resolve themselves into PbTiO3, ZrO2 and (PbO) when the lead deficiency caused by thermal treatment increases.