Unique high temperature polarization stability state in Bi_0.5Na_0.5TiO₃-BaTiO₃system at the morphotropic phase boundary

Abstract

The high‐temperature stability of piezoelectric property is an important merit for applications at elevated temperatures. However, understanding the depolarization mechanism is a fundamental issue that remained unclear for decades. In this study, the ex situ depolarization behavior between open‐circuited and short‐circuited annealed samples is measured for (1–x)Bi0.5Na0.5TiO3–xBaTiO3 (BNT–xBT) ceramics. A unique high temperature polarization stability state with respect to the prominent improvement depolarization temperature is observed for the morphotropic phase boundary (MPB) composition (x = 0.06) with open‐circuited annealed samples. It is suggested that this enhancement can be attributed to the alignment of the nanodomains induced by the bias fields.