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This paper presents the results of preparing and investigating the solid solution of lead barium zirconate titanate stannate (Pb1−xBax)[(Zr1−yTiy)1−zSnz]O3 with x = 0.25, y = 0.35 and z = 0.00, 0.02, 0.04, 0.08, 0.10. Ceramic samples were obtained from oxides and carbonates using conventional ceramic technology and pressureless sintering. The results of Energy‐dispersive X‐ray spectroscopy (EDS) investigations, XRD studies, as well as dielectric measurements and electromechanical investigations are presented. It was stated that at the room temperature, the structure of the investigated samples is pseudo‐cubic, typical for relaxors. Maximal value of elementary cell parameter is observed for z = 0.02, and for higher values of z, we observe almost linear decrease with increasing z. It was found that with increasing content of the Sn, the temperature Tm at which dielectric permittivity reaches its maximum decreases. Analyzing P‐E hysteresis loops it was stated that the phase transition in the investigated samples takes place at temperatures approximately 100°C lower than the temperature of the dielectric permittivity maximum. The temperature of phase transition was calculated also from hysteresis loops and compared with that obtained from measurements of dielectric permittivity.

In the work, the multicomponent Pb 0.75 Ba 0.25 (Zr 0.65 Ti 0.35 ) 1-a Sn a O 3 (PBZT/Sn) ceramics were obtained with various tin amounts (a from the range of 0.0 to 0.1). The densification of the PBZT/Sn ceramic samples was performed using pressureless sintering method. The effect of SnO 2 content on the crystal structure of PBZT/Sn ceramics, microstructure, DC electrical conductivity and electrophysical properties (including dielectric and ferroelectric testes), were investigated. The PBZT/Sn ceramic samples exhibit high values of dielectric permittivity at the temperature of ferro-paraelectric phase transition and show the relaxor character of phase transition. Excessive SnO 2 contents doping of the PBZT/Sn materials (already for a = 0.1) might lead to lattice stress and structure defects, which successively leads to the deterioration of ferroelectric and dielectric properties of the ceramic samples. The presented research shows that the addition of SnO 2 to the base PBZT compound (in the proper proportion) gives an additional possibility of influencing the parameters essential for practical applications, from the areas of micromechatronics and microelectronics.

The multiferroic (ferroelectric–ferromagnetic) composites (PFN–ferrite) based on ferroelectromagnetic PbFe1/2Nb1/2O3 powder and ferrite powder (zinc–nickel ferrite, NiZnFeO4) were obtained in the presented study. The ceramic PFN–ferrite composites consisted of 90% powder PFN material and 10% powder NiZnFeO4 ferrite. The ceramic powders were synthesized by the classical technological method using powder calcination, while densification of the composite powders (sintering) was carried by two different methods: (1) free sintering method (FS) and (2) spark plasma sintering (SPS). The composite PFN–ferrite samples were thermally tested, including DC electrical conductivity and dielectric properties. Besides, XRD, SEM, EDS (energy-dispersive spectrometry) and ferroelectric properties (hysteresis loop) of the composite samples were tested at room temperature. At the work, a comparison was made for the results measured for PFN–ferrite composite samples obtained by two methods. The X-ray examination of multiferroic ceramic composites confirmed the occurrence of the strong diffraction peaks derived from ferroelectric (PFN) matrix of composite as well as weak peaks induced by the ferrite component. At the same time, the studies showed the absence of other undesired phases. The results presented in this work revealed that the ceramic composite obtained by two different technological sintering methods (free sintering method and spark plasma sintering technique) can be the promising materials for functional applications, for example, in sensors for magnetic and electric fields.

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In the presented work composite ferroelectric/ferrimagnetic ceramics have been obtained and described. The investigated material is based on PMN-PT powders and Ni-Zn ferrite powder. The Powders of ferroelectric component (i.e. (1–x)PMN-(x)PT with x from 0.25 to 0.40 with step 0.03 were synthesized using the sol-gel method. The magnetic component i.e. nickel-zinc ferrite was obtained from oxides using the classic method of obtaining ceramics. The compositions of PMN–PT used by us have rhombohedral or tetragonal symmetries, or belong to morphotropic region. The final ceramic composite samples were obtained using the classic method of ceramic technology with calcination route and final pressureless densification using free sintering. In this paper, XRD, EDS dielectric and magnetic properties have been investigated and described for the obtained composite ceramic samples.

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In this work, the ceramics with the general formula of Pb 0.75 Ba 0.25 (Zr 0.65 Ti 0.35 ) 1-z Sn z O 3 (PBZST) for a constant x = 0.25, constant y = 0.35 and variable z = 0, 0.02, 0.04, 0.06, 0.08, 0.10 were obtained and examined. Powders synthesis was carried out using calcination method in conditions of: T calc = 850 • C/t calc = 3 h, and densification using free sintering method in conditions of: T s = 1250 • C/t s = 4h. For the obtained samples of PBZT and PBZTS ceramics, the microstructure and basic dielectric properties in the frequency function tests were performed.The PBZTS ceramics with relaxor properties is an interesting material to use in the modern electrical engineering, for instance as electrostriction transducers, sensors, or pulse capacitors.