Effect of sintering temperature on the depolarization behavior of (Bi 0.5 Na 0.5 )TiO 3 ‐based ceramics

Abstract (Bi 0.5 Na 0.5 )TiO 3 (BNT)‐based ferroelectric ceramics have drawn extensive attention because of their excellent electrical properties and interesting depolarization behavior. However, the poor thermal stability of electrical properties limits their practical application. In this work, the effect of sintering temperature ( T s ) on the depolarization behavior of BNT‐based ceramics was systematically investigated. It is found that the depolarization temperature T d determined from pyroelectric measurement tends to decrease with increasing T s , which indicates that lower T s defers the ferroelectric‐relaxor (FE‐RE) phase transition. However, for the samples sintered at higher T s (such as 1180°C), although the T d is reduced, the thermal stability is better compared with the sample sintered at lower T s (1100°C) because the diffuse behavior of the FE‐RE phase transition is suppressed. According to these results, we propose that the thermal stability of electrical properties for BNT‐based ceramics is not only related to high T d , but also to the diffuse degree of phase transition.