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Comprehensive studies of radiation effects on the optical and dielectric properties of PLZT X/65/35 ceramics have been made. The samples have been exposed to gamma-electron and reactor neutron irradiation.

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.

Pyroelectric and dielectric properties and switching of ferroelectric PLZT ceramics have been studied in the range 290–470 K. The effect of γ-irradiation on pyroelectric coefficient, dielectric permittivity and rate of Barkhausen jumps sequence at polarization switching of PLZT ceramics is found to be most pronounced at phase transition.

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.