Critical temperature below the Curie temperature of ferroelectric ceramics PZT

Abstract

The article presents the results of research the pre-transitional features of the behavior of solid solutions based on lead zirconate-titanate. The presence of a “special” critical temperature [Formula: see text] on the temperature dependences of the permittivity [Formula: see text] and the remanent polarization [Formula: see text], preceding the temperature of the paraelectric phase transition at the Curie temperature [Formula: see text], is noted. In the temperature range [Formula: see text] < [Formula: see text], the [Formula: see text] dependence obeys a power law. In the temperature range [Formula: see text]<[Formula: see text]<[Formula: see text], this law is not fulfilled. The results of X-ray experiments make it possible to associate this behavior with reversible disordering at [Formula: see text]<[Formula: see text] of an ordered domain structure formed during the polarization of piezoelectric ceramics and with its irreversible disordering in the temperature range [Formula: see text]<[Formula: see text]<[Formula: see text]. This is due to the appearance of internal mechanical stresses in a polycrystalline ferroelectric due to irreversible depolarization of the samples at temperatures [Formula: see text]<[Formula: see text]<[Formula: see text].