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The ferroelectric properties and strain behaviors of 0-3-type-ceramic composites were investigated. (100-x)Bi0.5(Na0.75K0.25)TiO3-xBiAlO3 (x = 5, 6, and 7: abbreviated as 95BNKT-5BA, 94BNKT-6BA, and 93BNKT-7BA, respectively, and the three compositions are altogether designated as BNKT-BA) were chosen as a matrix materials, and ferroelectric Bi0.5Na0.5TiO3 (f-BNT), Bi0.5(Na0.8K0.2)0.5TiO3 (f-BNKT), and 98.5Bi0.5(Na0.8K0.2)0.5TiO3-1.5BiAlO3 (f-BNKTBA) grains as inclusions. Large f-BNT, f-BNKT, and f-BNKTBA grains strongly affect the ferroelectric properties and strain behaviors of the BNKT-BA matrix in the composite. In 95BNKT-5BA with f-BNT and f-BNKT, negative strain was observed, indicating that the ferroelectric phase is formed and stabilized. 93BNKT-7BA with f-BNT, f-BNKT and f-BNKTBA showed an increase in positive strain, which is associated with low field-induced phase transition. It was found from the strain curve that two contributions, ferroelectric phase stabilization and phase transition activation, were involved in the strain behaviors of the ceramic composites. [ABSTRACT FROM AUTHOR]

La-modified lead zirconate titanate Pb1.075La0.025(Zr0.95Ti0.05)O3, antiferroelectric thin films are fabricated by excimer laser ablation technique on Pt/Ti/SiO2/Si substrates. The measured dielectric constant and dissipation factor are 642 and 0.021 at room temperature, respectively, and Curie temperature is 196 °C. The antiferroelectric double hysteresis loops of Pb1.075La0.025(Zr0.95Ti0.05)O3 film are confirmed by measuring the polarization vs. the electric field. With increasing temperature, the double hysteresis loop behavior is reduced and gradually becomes a loose single ferroelectric hysteresis loop. The complex dielectric constants and a.c. conductivities are measured as a function of frequency (10−2–106 Hz) and temperature (25–250 °C) in order to investigate the influence of microstructure on the charge transport mechanism. We observe the strong low-frequency dielectric dispersion due to migration of thermally activated oxygen vacancies at higher temperature above 175 °C. The activation energy calculated from the a.c. conductivity is 0.63 eV. [Copyright &y& Elsevier]