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L. Kozielski and M. Adamczyk

Magnetic and Piezoelectric Properties of Magnetoelectric Laminate Transformer

Modern electronic devices development steady trends toward miniaturization and multifunctionality. The application of such advanced devices is often realised by superimposing two different effects. In recent years, there was great interest shown in multiferroic materials in form laminated heterostructures taking advantage of mentioned superposition. In these stacked structured electric and magnetic properties are strain coupled leading to the possibility of controlling either magnetic polarization by application of electric fields or electric polarization by means of applied magnetic fields.

In this paper novel construction of piezoelectric transformer was proposed with electric current induced magnetic field generation, without any coil or wires. This magnetoelectric laminate Piezoelectric Transformer from one layers of investigated piezoelectric material and second layer of commercial magnetostrictor was fabricated. This construction exhibits many interesting and unusual piezomagnetic properties and a demonstration of output voltage gain controlling via the application of magnetic field across the new heterostructure is presented.

Open access

M. Adamczyk, L. Kozielski, R. Zachariasz, M. Pawełczyk and L. Szymczak

Abstract

The research presented in this paper concerns BaBi2Nb2O9 (BBN) which is the member of the Aurivillius family and seems to be interesting from the point of view of its potential applications in storage media. Our investigations focused on temperature dependence crystal structure and mechanical properties of this ceramics as well as on the dielectric properties of samples. Correlation between positions of the maximum of the real part of electric permittivity and the behavior integral width of diffraction lines XRD versus temperature had been discussed based of the presence of polar nano-regions with orthorhombic distortion in macroscopic tetragonal matrix.

Open access

L. Kozielski, M. Adamczyk, K. Feliksik, D. Bochenek and F. Clemens

Abstract

Electrocaloric (EC) structures for a new generation of cooling or heating elements utilize the temperature dependence of spontaneous polarization in some ferroelectric materials to convert waste heat into electricity and vice versa. A (Pb0.93La0.07) (Zr0.65Ti0.35)O3 material, have the largest recorded pyroelectric coefficient. An effective predicted form for such applications is fiber, due to small heat capacitance and quick response time, even for nano second laser excitation. Consequently, the presented work provides a description of the optimization of structural, ferroelectric and piezoelectric properties of obtained fibers, finally concluding on necessity of sintering temperature reduction in 100°C in contrast to bulk form to effectively prevent its destruction.

Open access

M. Adamczyk, L. Kozielski, M. Pawełczyk and M. Pilch

Dielectric and Mechanical Properties of BaBi2(Nb0.99V0.01)2O9 Ceramics

The BBN ceramics doped by vanadium have been broadly recognized by using nano indentation techniques and ultrasound velocity and measurements. The results affirm that the vanadium admixture significantly improved the mechanical quality of ceramics. Such a small dopant doesn't change the dielectric properties, but we obtain visible increasing of the dielectric permittivity value and shifts the temperature of the εmax to higer values. The vanadium admixture decreased the diffusion degree γ as well as influenced on the parameters characteristic for the relaxor behaviour. Our suggestion is that partial substitution of the smaller vanadium ions into the niobium sites renders for example ordering of the dipoles.

Open access

M. Adamczyk, J. Kusz, W. Hofmeister, M. Zubko, L. Kozielski, M. Pilch, D. Bochenek and B. Wodecka-Duś

Abstract

The subject of the paper is lead free bismuth layer structure oxides (1-x)Bi3TiNbO9-xBaBi2Nb2O9 (x=0; 1; 2; 3 mol). The influence of Bi3TiNbO9/BaBi2Nb2O9 ratio on dielectric and structural properties was studied in a wide range of temperatures. Change in the ratio causes a decrease in the maximum value of dielectric permittivity and shifts the temperature of ε’max to low values, leading to linear decreasing of average grain size and linear increasing of ceramics density. These results indicate an augment of the packing degree and the participation of pores are significantly decreased with the increase of BaBi2Nb2O9 compound intake. Moreover, for 0.7Bi3TiNbO9-0.3BaBi2Nb2O9 ceramics the dielectric phase transition is broadened and the properties characteristic for the ferroelectric relaxor appear.

Open access

B. Wodecka-Dus, L. Kozielski, J. Erhart, M. Pawełczyk, D. Radoszewska, M. Adamczyk and D. Bochenek

Abstract

Effects of La3+ admixture in barium lanthanum titanate (BLT) ceramics system with colossal permittivity on performance of prospective piezoelectric cold plasma application were studied. Usage of cold atmospheric pressure plasma appears promising in terms of industrial and healthcare applications. Performed investigation provide consistent evaluation of doping lanthanum amount on piezoelectric coefficients values with simultaneous capability of charge accumulation for effective plasma generation. Modification of ferroelectric materials with heterovalent ions, however with the lower radii than the original atoms, significantly affects their domain mobility and consequently electromechanical properties. To determine the piezoelectric coefficients, the resonance-antiresonance method was implemented, and values of piezoelectric and dielectric parameters were recorded. Finally the results indicated that addition of 0.4 mol.% of La3+ ions to the ceramic structure maximally increased the values of piezoelectric coefficient to d 33 = 20 pC/N and to huge dielectric constant to ε 33 T = 29277.

Open access

B. Wodecka-Dus, M. Adamczyk, T. Goryczka, J. Dzik, D. Radoszewska, L. Kozielski and D. Bochenek

Abstract

The present paper widely describes the details of technology of (Ba0.6Pb0.4)TiO3 ceramics modified with PbO-B2O3-Al2O3-WO3 special glass, as well as the influence of admixture on the microstructure and crystal structure of basic material. The microstructure investigations reveal the significant increase of grain size and a decrease of pores participation in volume of modified samples, whereas the X-Ray Diffraction (XRD) measurements show a decrease of the volume of unit cell. The obtained results are discussed due to processes occurring during the sintering process at high temperature.