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Lead-zirconate-titanate PbZr_1-xTi_xO₃ has superb ferroelectric properties in x~0.48 morphotropic phase boundary phase. In bulk form it has a P4mm tetragonal crystal structure of lattice parameters a=0.4036 nm and c=0.4146 nm at room temperature or above, and a Cm monoclinic structure of a=0.5722 nm, b=0.5710 nm, c=0.4137 nm and β=90.50° at lower temperatures. A new polymorph lies in an orthorhombic structure of a=0.4038 nm, b=0.4017 nm, and c=0.4148 nm in small particles of size such as 20 nm. It has an enhanced value of density of 8.033 g/cm³ relative to 8.006 g/cm³ in the tetragonal or 8.000 g/cm³ in the monoclinic bulk structure in a rather incompressible and hard material. The result is analyzed with X-ray diffraction of the sample of nanoparticles.

The influence of sintering atmosphere and copper addition on the microstructural and piezoelectric properties of Mn-doped lead zirconate titanate ceramics (PZT) was investigated. This ceramic powder densifies below 1000°C, enabling the use of copper inner electrodes for a multilayer actuator setup. To simulate the influence of oxidized inner electrodes during sintering, different CuO contents (0 and 1 mol.%) were mixed to the precalcined Mn-doped PZT powder. Ceramic discs were sintered at 950°C in air and analogously in N₂, or in steam containing N₂ (25 vol.% water vapor content). The electrical characterization of the discs showed that the piezoelectric properties are influenced by the CuO addition as well as by the sintering atmospheres. The large signal piezoelectric constant shows an improvement of at least 20% when CuO is added. CuO acts as a sintering aid, and especially when the ceramics are fired in steam-containing N₂, anomalous grain growth occurs.

Main aim of the presented paper is the theoretical analysis and experimental verification of the transformation parameters for the new type of nonhomogeneously poled ring transformer. The input part is poled in the thickness direction and output part in the radial direction. Two transformer geometries are studied — the input part is at inner ring segment, or it is at the outer ring segment. The optimum electrode size aspect ratios have been found experimentally as $d_1∕D\approx 0.60-0.65$ for the ring with aspect ratio $d∕D=0.2$. The fundamental as well as higher overtone resonances were studied for the transformation ratio, the optimum resistive load, efficiency and no-load transformation ratio. Higher overtones have better transformation parameters compared to the fundamental resonance. The new type ring transformer exhibits very high transformation ratios up to 200 under no-load and up to 13.4 under a high efficiency of 97% at the optimum load conditions of 10 $\mathrm{k}\mathrm{\Omega }$. Strong electric field gradient at the output circuit is applicable for the electrical discharge generation.

Low frequency Raman spectra of (${\text{Pb}}_{0.97}$${\text{La}}_{0.02})$(${\text{Zr}}_{0.864}$${\text{Sn}}_{0.04}$${\text{Ti}}_{0.096})$O₃ ceramic samples have been studied near cubic to antiferroelectric phase transition at about 200^∘C. A set of low frequency soft modes were observed restoring below the transition point, in addition to the known one above 100cm${}^{-1}$. These modes show strong damping anomalies at the transition point that supposes considerable intermode interactions via dampings.