Dielectric spectroscopy of ceramic solid solutions based on modified lead titanate
Abstract
Dielectric spectroscopy of ceramic solid solutions based on modified lead titanate
Incoming article date: 21.04.2015The manuscript traced the impact of changes in the content of alkaline-earth elements on the dielectric spectra of solid solutions based on lead titanate. Two concentration areas with sharply differing nature of the manifestations of dispersion phenomena were identified. First (0.02≤α1≤0.24) is characterized by strong dispersion ε/ε0 in all temperature range and not allow to generate maximum of ε/ε0 for Curie temperature at low frequencies, the second (0.24≤α1≤0.36) - a sharp decrease of Δε in the ferroelectric phase and complete disappearance of it in the solid solutions, SS, with α1 = 0.36, indicating stabilization of the structure with the introduction of alkaline SS elements. It was found that as increased the concentration of modifiers in the compositions there is a stabilization of their structure with a gradual decrease in the phase transition temperature. Formation of two concentration areas where changes macro properties SS is undoubtedly a consequence of their correlation with the phase diagram of the studied SS, which is experiencing a transformation in the neighborhood of α1 ~ 0.24, due to the transition from two-phase to single-phase state. The results obtained by the authors can be used in the development of high-temperature (α1 0.24 ) anisotropic ferroelectric materials.
Keywords: ferroelectric piezoceramics, lead titanate, alkaline earth elements, modifiers, solid phase synthesis dielectric spectra