Ultra-large electromechanical deformation in lead-free piezoceramics at reduced thickness
Xiang He, Muzaffar Ahmad Boda, Chen Chen, Rongmin Dun, Lu Wang, Yizheng Bao, Dongfang Pang, Lin Guo, Huarong Zeng, Yongxiang Li, Zhiguo Yi
Abstract
(BNT-BT) ceramics with highly asymmetric strain-electric field curves. Further analyses of the polarization switching process reveal that the boosted strain curves originate from the bending deformation driven by asymmetric ferroelastic switching in the surface layers. Based on this, one monolayer BNT-BT was designed to realize digital displacement actuation and a scanning mirror application with a maximum mirror deflection angle of 44.38°. Moreover, the surface effect-induced bending deformation can be extended to other piezoceramics, accompanied by derived shape retention effects. These discoveries raise the possibility of utilizing thickness engineering to design large-displacement actuators and may accelerate the development of high-performance lead-free piezoceramics.