Enhanced dielectric and ferroelectric properties of lead-free Ba(Zr0.15Ti0.85)O3 ceramics compacted by cold isostatic pressing

Nano-sized zirconium substituted barium titanate, Ba(Zr0.15Ti0.85)O-3, hereinafter referred to as BZT was synthesised using high energy ball milling. Calcined powders were compacted using cold-isostatic pressing. Phase pure perovskite BZT, free from any secondary peaks was observed for sintered samples with a relative density similar to 98%. High permittivity of similar to 14,000 coupled with a dielectric loss of <2% were measured on these samples. A high remanent polarization of similar to 10 mu C/cm(2) and an electric field induced unipolar strain of 0.1% at relatively low fields (similar to 40 kV/cm) at room temperature are other characteristic highlights of these ceramics. The effect of hysteresis parameters such as voltage, frequency and temperature on the polarization and electric field induced strain are also reported in this paper. The observed enhanced dielectric, ferroelectric and piezoelectric properties can be a result of the contribution of all polar vectors of various coexisting phases at the composition studied and are comparable to single crystals of the same composition. (C) 2014 Elsevier B. V. All rights reserved.