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Contact effects (Au-electrodes) in ferroelectric Sr3/44Ba1/4Nb2O6(SBN) result in a thickness dependence of the measured dielectric constant and loss. The contribution of contact and bulk dielectric properties is separated using the series of two parallel RC circuits for electric field both parallel and perpendicular to the ferroelectric axis. The temperature as well as the frequency dependence of the bulk and surface dielectric properties are different. The particular dielectric properties of the surface layer are accounted for by electrical inhomogeneities within the contact region. The types of possible inhomogeneities are evaluated using finite element method computer simulations. The best agreement between experimental measurements and a two-dimensional RC net computer simulation were achieved calculating the model with holes and reoriented RC elements under the electrodes.

An experimental study of the distribution of the light extinction with respect to absorbtion and scattering in hot-pressed PLZT 9.75/65/35 at the wavelength 0.425 – 5.56 μm is reported. The light scattering spectrum is explained by the Usov-Shermergor theory. The diameter of pores (0.13 μm) and pore concentration (1.7 · 107 cm−3) are determined.

The optical transmitance, crystallographic structure and dielectric properties for PLZT 8/65/35 samples either containing a number of various dopands (Mn, Fe, Co, Eu), or subject to neutron or electron irradiation have been studied.

Results of light absorption, x-ray diffraction and dielectric studies of Mn, Fe, Co and Eu-doped PLZT ceramics are reported. Most of them are qualitatively explained by dopant-induced change of vacancy concentration in sublattice A (and/or B) as well as in the oxygen sublattice. Possible use of the ideas of on-off effects of B(A) ions are discussed to explain relaxor properties and some other features of the PLZT ceramics.

The sequence of phases formed during the solid state reaction in oxide mixtures has been studied by X-ray diffraction and differential thermal analysis (DTA) in the binary oxide system PbO-Nb2, O5 and the ternary oxide system PbO-Nb2O5-Sc2O3. The following compositions have been investigated: 3PbO : 2Nb2O5, 2PbO : Nb2O5, 5PbO : 2Nb2O5, 3PbO : Nb2O5, 4PbO : Nb2O5, and 3PbO : 2Nb2O5 : X, 2PbO : Nb2O5 : X, 5PbO : 2Nb2O5 : X, 3PbO : Nb2O5 : X, 4PbO: Nb2O5 : X, the molar ratio X of Sc2O3 being taken 0; 0.025; 0.05; 0.1; 0.3; 0.5; 0.8; 1.0; 1.2.It is found that the formation of both the binary and ternary compounds includes complicated multistage processes with several intermediate products during the reaction. In all cases, except 3PbO : 2Nb2O5, one or more additional phases less rich in lead oxide coexist with the stoichiometric phase. Obviously, this is due to evaporation of lead oxide above 800°C. Therefore PbSc1/2Nb1/2O3, produced from the stoichiometric proportion of oxides 4PbO : Nb2O5 : Sc2O3 by a solid...

PLZT and PSN transparent ferroelectric ceramics have been subjected to γ-irradiation (energy ≈ 1;15 MeV; power of the dose 1050 r/s; doses up to 3 × 109 rad), electron irradiation (energy ≈ 4.5 MeV; power of the dose ≈ 1012 electr./cm2 · s: doses up to 1018 electr./cm2) and direct irradiation in a thermal reactor channel (neutron energy ≥ 0.1 MeV; flow density from 1.8 × 1011 to 2.4 × 1012 n/cm2 s: the dose up to 1018 n/cm2).Results of complex X-ray, dielectric, and optical studies of the irradiated ceramics are interpreted in terms of radiation-induced defect interaction with the real structure defects of the initial material taking into account the chemical and phase constitution, as well as the defectness and ordering of structural elements at different levels of the latter.

PLZT and PSN ceramics have been exposed to γ-radiation (energy ≈ 1.15 MeV, dose up to 3 · 109 rad), electron flux (≈4.5 MeV, dose up to 3.1018 electr./cm2) and fast neutrons (≥ 0.1 MeV, dose up to 1018 n/cm2). The irradiated material was used to study radiation effects on dielectric parameters (e and tgδ were measured at frequencies from 1 kHz to 5 MHz), polarization (dielectric hysteresis quasistatic loops) and non-linear optical properties (I2w). The measurements were made in the region of phase transition as well as to examine annealing of radiation-induced defects. As compared to PLZT the PSN ceramics is more resistant to radiation, the most sensitive PLZT compounds being with 7 ≤ × ≤ 9.5 at .% of La. Obtained results are explained by the change of ion charge, redistribution of vacancies in A and B sublattices of PLZT and by possible ion ordering in sublattice B of PSN with account for intrinsic fields in the relevant compounds.