Bipolar and Unipolar Fatigue of Ferroelectric BNT‐Based Lead‐Free Piezoceramics

Abstract

The bipolar and unipolar fatigue behavior of the lead‐free piezo‐ and ferroelectric 0.94Bi 1/2 Na 1/2 TiO 3 –0.06BaTiO 3 (94BNT–6BT) was investigated. To obtain a complete profile of the fatigue behavior, both large‐signal (polarization, strain) and small‐signal ( d 33 , ɛ 33 ) properties were measured at room temperature. The results indicate that the material suffers a significant degradation in both large‐ and small‐signal properties after cycling, with most of the fatigue occurring in the first 10 4 cycles of the fatigue test.