| 초록 |
This work investigated the crystallographic structure, microstructure, ferroelectric, and piezoelectric properties of lead‒free (1–x–y)(Bi1/2Na1/2)TiO3–xSrTiO3‒yBiAlO3 (BNT‒ST‒BA, x = 0.20 ∼ 0.28, y = 0 ∼ 0.04) piezoelectric ceramics. BNT–ST–BA ceramics were prepared by conventional solid solution reacted method. BA modification has no remarkable effect on the microstructure and crystal structure of BNT-ST ceramics. However, a significant change in the temperature dependence of dielectric properties was revealed. With increasing BA content, ferroelectric (FE) to ergodic relaxor ferroelectric (RFE) transition temperature was clearly shifted to lower temperature. Besides, remanent polarization (Pr) and coercive field (Ec) were decreased with increasing amount of BA. At normal-to-relaxor FE phase boundary, the highest normalized strain was found to be 707 pm/V at x = 0.24 and y = 0.01 under 3 kV/mm, which is considered as a promising candidate for the lead‒free actuator materials. |
