Wyniki wyszukiwania - Biblioteka Nauki

1

Phenomena O the Internal Friction Present in the Ceramic Ferroelectric Materials Below the Curie Temperature

100%

Ilczuk J.

|

2002

|

tom Vol. 23

167-174

2

Wybrane właściwośi fizyczne warstwy wierzchniej węglików spiekanych gatunku G20 po szlifowaniu elektrochemicznym

63%

Zaborski S. , Ilczuk J.

|

2002

|

tom nr 9

17-22

PL

Celem tego artykułu jest przedstawienie stanu technologicznej warstwy wierzchniej po procesie szlifowania elektrochemiczego. W szczególności podane zostały wybrane właściwiści fizyczne na powierzchni węglików spiekanych, takie jak: magazynowanie energii, tarcie wewnętrzne oraz mezotwardość i gęstośc dyslokacji.

EN

Presentation of the state of the surface layer after electrochemical grinding. The electrochemical grinding process widens the influence upon the producibility properties of the surface layer in relation to the traditional grinding of metals. The shaping of the surface layer during the electrochemical grinding has an essential effect on energy storage. The run of the energy storage curve can be roughly assumed asa result of two simultaneous processes: a migration of the existing defects - mainly dislocations, and crea-tion of new ones. Measurements of internal friction have shown that there is an interaction of the dislocation and hydrogen with the material being worked, which is an evidence of the occurence of dissipation of internal energy.

3

Wpływ defektów strukturalnych na zjawiska tarcia wewnętrznego w piezoceramice typu PZT

63%

Zachariasz R. , Ilczuk J.

Prace Naukowe Instytutu Telekomunikacji i Akustyki Politechniki Wrocławskiej. Konferencje

|

2001

|

tom Vol. 83, nr 27

453-458

EN

Possibility of use of the piezoelectric ceramics in the electronics industry, medical equipment and electroacoustic is determined by stability of its mechanical and electric parameters. Significant influence on the work stability of the piezoelectric converters has optimization of the technological process, selection of the PbTiO3 concentration in the solid solution of the PZT type and also modification of the basic chemical composition. To investigate real structure of the piezoelectric ceramics and especially to define mechanism, which is responsible for the making various structural defects, such as pointer defects or dislocation, quite often non-destructive methods, such as: internal friction, ultrasonic defectoscopy and resonance-antyresonance, are used. In the present work, results of investigation of internal friction and dynamic Young modulus of the PP6S ceramics, which have been measured in the temperature range 275 K - 650 K, were discussed. The ceramics of symbol PP6S was obtained by classical method at University in Rostov in Russia. The maxima have been observed on the curves presented the temperature dependence of internal friction. We related them with the ferroelectric-paraelectric phase transition and the various domain structures. Changes of the curve E = f(T) have been observed in the temperature range where maxima of internal friction occurred.

4

The Influence of the Irradiation on the Dielectric and Mechanical Properties of the PZTType Piezoceramics

63%

Zachariasz R. , Ilczuk J.

|

2002

|

tom Vol. 23

443-450

5

In Influence of the PbTiO3 Content on the Piezoelectric Propertie of a Multicomponent Piezoceramic of the Pzt Type

63%

Bruś B. , Ilczuk J.

|

2001

|

tom Vol. 22

37-44

6

An Influence of the PbTiO3 Content on the Piezoelectric Proporties of a Multicomponent Piezoceramic of the PZT Type

63%

Bruś B. , Ilczuk J.

|

2002

|

tom Vol. 23

83-90

7

The Influence of The Irradiation on the Dielectric and Mechanical Properties of the Pzt Type Piezoceramics

63%

Zachariasz R. , Ilczuk J.

|

2001

|

tom Vol. 22

285-292

8

Zastosowanie metody tarcia wewnętrznego w badaniach piezoceramiki

63%

Zachariasz R. , Ilczuk J.

Zeszyty Naukowe. Matematyka - Fizyka / Politechnika Śląska

|

1999

|

tom z. 87

145-152

PL

W pracy prezentowane są badania tarcia wewnętrznego i dynamicznego modułu Younga (E) w zakresie temperatur 200 K - 690 K ceramiki o symbolu S-I, wyprodukowanej przez Zakłady Ceramiki Radiowej "Cerad" w Warszawie. Na krzywych tarcia wewnętrznego obserwowane jest maksimum, odpowiadające przejściom fazowym z romboedrycznej struktury R3c do romboedrycznej struktury R3m (T=265K), maksimum odpowiadające ferroelektryczno-paraelektrycznemu przejściu fazowemu (T=640K), a także dwa następne maksima związane z właściwą strukturą domenową. W obszarze występowania tarcia wewnętrznego obserwowane są zmiany na krzywej E=f(T).

EN

In the present work, the internal frictions and the dynamic Young modulus of ceramics have been measured in the temperature range 200K - 690 K. The ceramics of symbol SI was manufactured by Radio Ceramics Factory ,,CERAD" in Warsaw. Four maxima have been observed on the curves presented the temperature dendence of internal friction. Ww related them with the phase transition from rhombohedral R3c structure to the rhombohedral R3m structure (at T = 265K), with the ferrolectic-paraelectric phase transiton (at T = 640K), while the two last maxima could be related to the various domain structures. Changes of the curve E = f(T) have been observed in the temperature range where maxima of internal friction (IF) occured.

9

Internal friction related to the mobility of domain walls in sol-gel derived PZT ceramics

51%

Zarycka A. , Zachariasz R. , Ilczuk J. , Chrobak A.

Materials Science Poland

|

2005

|

tom Vol. 23, No. 1

159--165

EN

Internal friction Q-1 and Young's modulus E were measured as functions of temperature for undoped Pb(Zr0.65Ti0.35)O3 ceramics obtained by the sol-gel technique. Experiments were performed with a RAK-3 resonant mechanical spectrometer. The E(T) curves show two anomalies associated with two peaks, PR and PF, in the Q-1(T) dependence. Moreover, Q-1(T) curves recorded for two different frequencies show that the PR peak has a relaxation character. It was found that its activation energy and relaxation time should be attributed to the interaction of domains with point defects.

10

Application of the sol-gel metod to deposition of thin films

51%

Zarycka A. , Ilczuk J. , Czekaj D.

Materials Science

|

2003

|

tom Vol. 21, No. 4

439-443

EN

A method for synthesizing ferroelectric thin films of lead zirconate-titanate (PZT) and lead-lanthanum zirconate-titanate (PLZT) by a modified sol-gel technique is reported. The following chemical compositions with the Zr/Ti ratio were obtained: PZT 65/35 and PLZT 6.5/65/35. Thin films, prepared from acetate and alkoxide precursors of La, Pb, Zr and Ti, were deposited on stainless steel and MgO substrates by spin coating. Crystallization of PZT-based electroceramic thin films was performed by thermal annealing at the temperature range of 550-700 st.C. The structure of the thin films was investigated by X-ray diffraction. The formation of the perovskite-type structure was confirmed. Microstructure was investigated by the optical microscopy. Technological conditions of the preparation of thin films were optimized.

11

Real Structure of Pzt Type Ceramics Obtained by the Sol - Gel Method

51%

Zarycka A. , Zachariasz R. , Bruś B. , Ilczuk J.

|

2003

|

tom Vol. 24

255-260

EN

In the present work, the results of investigations of the real structure of PZT 65/35 piezoceramics obtained by sol - gel method are discussed. To characterize PZT ceramics the method of internal friction was used. The relationships between the chemical composition, crystalline structure and mechanical properties of piezoelectric ceramics were studies for the all samples.

12

The Internal Friction in the Phase Transition Area in the Pzt Type Ceramics

51%

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

|

2003

|

tom Vol. 24

249-254

EN

The aim of the present study was to measure phase tranistion temperatures and observe changes in the internal friction Q-1 and dynamic Young's modulus E in the area of these temperatures for the doped PZT ceramics, with the chemical composition: Pb0,975Ba0,01Ca0,01Sr0,005(Zr0,52Ti0,48)O3 + 1,4 wt% Bi2O3 + 0,3 wt% GeO. For all types of samples, on the temperature dependencies Q-1(T) two maxima of internal friction were observed: the relaxation peak PR and the PF peak originates from the ferroelectric-paraelectric phase transformation (Curie point).

13

The Optimalization of the Properties of the Multicomponent Pzt Type Ceramics by the Choice of Appropriate Technological Conditions

51%

Bruś B. , Czerwiec M. , Zachariasz R. , Ilczuk J.

|

2004

|

tom Vol. 25

213-218

EN

By the conventional ceramic sintering method, doped lead zirconate titanate (PZT) samples with the chemical composition 0.55PbTiO3-0.43PbZrO3-0.02[Pb(Cd0,5W0,5)O3] have been obtained from oxides PbO, ZrO2, TiO2, CdO, WO3. For the samples of A series, synthesis was led in the 1223 K temperature by 3 hours and in the case of the samples of B series, by 6 hours in the same temperature but in two parts (each 3 hours long). Both series were sintered in the 1423 K temperature by 6 hours. All samples were subjected to polarization (Tpol.=423 K, Epol.=30 kV/cm, tpol.=30 min.) and next dielectric (εT33/ε0, tgδ) properties were measured for the samples in the shape of discs. For the samples of B series, larger values of the dielectric permittivity εT33/ε0 were observed, as well as lower values of the dielectric oss tgδ.

14

Influence of Frequency on the Internal Friction of Pzt Type Piezoceramics

51%

Bruś B. , Ilczuk J. , Zarycka A.

|

2002

|

tom Vol. 23

91-96

15

The Stability of the Properties in PZT Based Ceramics

51%

Zachariasz R. , Czerwiec M. , Bartkowska J. , Ilczuk J.

|

2004

|

tom Vol. 25

249-256

16

Application of the Non Destructive Methods in the Investigation of The Ferroelectric Ceramics

51%

Bruś B. , Czerwiec M. , Zachariasz R. , Ilczuk J.

|

2003

|

tom Vol. 24

23-29

EN

This work shows the results of researches of the mechanical properties of the piezoelectric ceramics obtained by the hot pressing method. The measurements of the velocity of propagations longitudinal and transversal supersonic waves were carried out by ultrasonic defectoscope UMT-11. All measurement of the piezoelectric parameters such as: resonance and antiresonance frequency, the piezoelectric modulus, the electromechanical coupling coefficient, the tensor component of permittivity, elastic susceptibility were calculated by resonance-antiresonance method.

17

An Influence of the Domain Structire on Phenomena of the Intertnal Friction in the Pzt Type Piezoceramics

51%

Bluszcz J. , Zachariasz R. , Czerwiec M. , Ilczuk J.

|

2002

|

tom Vol. 23

57-62

18

Wpływ stanu powierzchni na zjawiska tarcia wewnętrznego w piezoceramice typu PZT

51%

Ilczuk J. , Dudek J. , Surowiak Z.

|

tom Vol. 19

103-109

EN

This paper investigates the phenomena of the internal friction and changes of the dynamic Young modulus for the multicomponent PZT type piezoceramic, with the use of an acoustic frequency relaxator. The studied samples were obtained by hot pressing and polishing surface. Temperature dependences of the internal friction, obtained during the heating--cooling measurement cycle made it possible to observe the maximum connected with the phase transition from the rhombohedral phase into the tetragonal phase and the maximum connected with the transition of the tetragonal phase into the cubic phase. In the case of samples in the initial state the temperature increase of piezoceramics from the transition temperature to reaching the Curie temperature, is accompained by the increase of the domain wall-mobility causing the rise of the internal friction. Polishing of the sample eliminates superficial layer with a considerable grade of stress created by a technological process. The superficial la; the polishing sample has c-domain structure (180° domain), whereas the interior of the sample has domains with 90° and 180" boundaries. Hence, polishing of the sample causes to create additional maximum of the internal friction connected with the c-domain structure. The transition of the ferroelectric phase to the paraelectric phase causes a drastic decrease of the internal friction value and of the dynamic Young modulus, due to the disappearance of the domain structure.

19

The determination of the magnetoelectric coupling coefficient in ferroelectric-ferromagnetic composite based on PZT-ferrite

51%

Bartkowska J. A. , Zachariasz R. , Bochenek D. , Ilczuk J.

Archives of Metallurgy and Materials

|

2013

|

tom Vol. 58, iss. 4

1401--1403

EN

In the present work, the magnetoelectric coupling coefficient, from the temperature dependences of the dielectric permittivity for the multiferroic composite was determined. The research material was ferroelectric-ferromagnetic composite on the based PZT and ferrite. We investigated the temperature dependences of the dielectric permittivity (ε) for the different frequency of measurement’s field. From the dielectric measurements we determined the temperature of phase transition from ferroelectric to paraelectric phase. For the theoretical description of the temperature dependence of the dielectric constant, the Hamiltonian of Alcantara, Gehring and Janssen was used. To investigate the dielectric properties of the multiferroic composite this Hamiltonian was expressed under the mean-field approximation. Based on dielectric measurements and theoretical considerations, the values of the magnetoelectric coupling coefficient were specified.

PL

W niniejszej pracy określono współczynnik sprzężenia magnetoelektrycznego na podstawie pomiarów temperaturowych zależności przenikalności dielektrycznej, wykonanych dla multiterroikowego kompozytu. Materiałem badań był ferroelektryczno-ferromagnetyczny kompozyt powstały na bazie PZT i ferrytu. Przebadano temperaturowe zależności przenikalności dielektrycznej (ε) dla kilku różnych częstotliwości pola pomiarowego. Z pomiarów dielektrycznych określono temperaturę przemiany fazowej z fazy ferroelektrycznej do fazy paraelektrycznej. Do teoretycznego opisu temperaturowych zależności stałej dielektrycznej zastosowano hamiltonian Alcantary, Gheringa i Janssena. Do badania własności dielektrycznych multiterroikowego kompozytu, hamiltonian ten został przedstawiony w przybliżeniu średniego pola. Bazując na pomiarach dielektrycznych oraz teoretycznych rozważaniach określono wartość współczynnika sprzężenia magnetoelektrycznego.

20

Stability of mechanical and dielectric parameters in pzt based ceramics

51%

Ilczuk J. , Bluszcz J. , Zachariasz R.

Hydroacoustics

|

2004

|

tom Vol. 7

69-78

EN

The (Pb0.9Ba0.1)(Zr0.53Ti0.47)O3 + 2% mol. Nb2O5 ceramics were prepared from high purity synthesized ceramic powders by a classical sintering method. Internal friction Q-1 and Young’s modulus E were measured as a function of temperature for the sample in the initial state and after ă irradiation 5 R dose. Two internal friction peaks P1 and P2, related to oxygen vacancies and domain walls, respectively, were observed in all measurements. In addition, a minimum in modulus E associated with a phase transition internal friction peak P3 appearing at curie temperature was observed. The internal friction results indicate the changes of concentration of oxygen vacancies and the domain structure, which will be helpful in the utilities of the PZT ceramics in transducers, ultrasonic generators, wave filters, etc.