Simultaneously enhancing the Td and the thermal stability of the real‐time d33 in BNT‐based piezoceramics

Abstract One of the inherent disadvantages of Bi 0.5 Na 0.5 TiO 3 ‐based (BNT‐based) piezoceramics is that an increment of the depolarization temperature ( T d ) is generally accompanied by a deterioration of the temperature stability of the real‐time piezoelectric constant ( d 33 ), which severely restricts the practical applications of the materials. Herein, we propose a new strategy to mitigate the conflict between the elevation of T d and the temperature stability of the real‐time d 33 in BNT‐based ceramics via integrating the pressure‐assisted sintering and quenching process. By this strategy, we not only increased the T d from 109 to 166°C but also improved the temperature stability of the real‐time d 33 (the temperature coefficient T tc = ± 13 pC/N) in 0.94Bi 0.5 Na 0.5 TiO 3 –0.06BaTiO 3 ceramic. Both the built‐in field and the increment of the field‐induced R 3 c phase fraction play the significant role in enhancing the T d and the temperature stability of the real‐time d 33 . Thus, our work provides a simple and effective approach for designing piezoceramics with high T d and a superior temperature stability of the real‐time d 33 .