Improved Ferroelectric, Piezoelectric And Electrostrictive Properties Of Dense BaTiO_3 Ceramic

摘要

The ferroelectric, piezoelectric and electrostrictive properties of BaTiO_3 (BT) dense ceramic synthesized by solid-state reaction were investigated. X-ray diffraction study confirmed tetragonal crystal structure having c/a ～1.0144. The dense microstructure was evidenced from morphological studies with an average grain size ～7.8 μm. Temperature dependent dielectric measurement showed the maximum values of dielectric constant, ε_r = 5617 at Curie temperature, T_c = 125 °C. The saturation and remnant polarization, P_(sat.)= 24.13 μC/cm~2 and P_r =10.42μC/cm~2 achieved respectively for the first time with lower coercive field of E_c = 2.047 kV/cm. The polarization current density-electric field measurement exhibits the peaking characteristics, confirms the saturation state of polarization for BT. The strain-electric field measurements revealed the "sprout" shape nature instead of typical "butterfly loop". This shows the excellent converse piezoelectric response with remnant strain ～ 0.212% and converse piezoelectric constant (d~*)_(33) ～376.35 pm/V. The intrinsic electrostrictive coefficient was deduced from the variation of strain with polarization with electrostrictive coefficient Q_(33)～ 0.03493m~4/C~2.