Large electrostrictive effect in Mn-doped BCZT ferroelectric ceramics

The electric field in ferroelectric ceramics can induce notable deformations or strains based mainly on the electrostrictive effect if the driving field is sufficiently large (normally larger than the coercive field). Therefore, a large electrostrictive effect is highly desired to achieve a high strain output. In the present work, 0.5Ba(Zr 0.2 Ti 0.8 )O 3 -0.5(Ba 0.7 Ca 0.3 )TiO 3 (BCZT50) ferroelectric ceramics doped with different numbers of Mn ions were synthesized and their dielectric and ferroelectric properties were studied to comprehensively evaluate the electrostrictive effect in this system. The doping levels were set as 0.0025, 0.005, 0.01, and 0.02. It was found that Mn ions could lower the temperature corresponding to the maximum permittivity, T m , drastically and induce diffuse phase-transition behaviors simultaneously. Most importantly, a purely electrostrictive effect with a longitudinal electrostrictive coefficient, Q 33 , as large as 0.0466 m 4 /C 2 was observed between 22 and 80 °C. The Q 33 of Mn-doped BCZT50 ceramics is much higher than some representative lead-based and lead-free ferroelectric ceramics. In this paper, a potential lead-free ferroelectric system with a large electrostrictive effect, which has potential applications in electrostrictive actuators, is reported.