Synthesis and dielectric properties of Pb 0.85 Ba 0.25 Zr 0.53 Ti 0.47 O 3 compounds with nano‐inclusions of Cu and Ni

Ceramic piezomaterials based on Pb 0.75 Ba 0.15 Zr 0.53 Ti 0.47 O 3 (PBZT) system are characterized by high values of the ferroelectric Curie temperature and polarization. They have widespread applications in electromechanical and electroacoustic transducers, bandwidth filters, transformers, frequency stabilized resonators, etc. Preparation of PBZT composites with nano‐inclusions of Cu and Ni have been carried out by a complex powder technology including metallization procedures which were performed by the well‐known chemical deposition method from standard solutions of copper and nickel. Studies of hydrostatic density and porosity of obtained samples as well as their microstructural investigations have yielded a larger density of PBZT‐metal composites (5.3 – 7.3 g/cm 3 ) as compared with pure PBZT (4.7 g/cm 3 ). Measurements of dielectric properties of samples in the frequency range from 20 Hz – 1 MHz have shown that the Curie temperature increases in PBZT (Ni) and decreases in PBZT(Cu) in comparison with pure PBZT. The complex dielectric permittivity of all investigated composites at higher temperatures and low frequencies is mainly caused by the high electrical conductivity. Only at the highest frequency used (1 MHz) the real part of the complex permittivity is caused by a resonant soft mode and could be fitted with the Curie‐Weiss law. The activation energy of ferroelectric domain mobility in PBZT (Cu, Ni) composites is lower than in pure PBZT. This can be explained by a decrease of the domain size in composites. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)