In situ electric field induced domain evolution in Ba(Zr0.2Ti0.8)O3-0.3(Ba0.7Ca0.3)TiO3ferroelectrics

In this work, the lead-free Ba(Zr0.2Ti0.8)O3-0.3(Ba0.7Ca0.3)TiO3piezoelectric ceramic was investigated in situ under an applied electric field by transmission electron microscopy. Significant changes in domain morphology of the studied material have been observed under an applied electric field. During the poling process, the domain configurations disappeared, forming a single-domain state. This multi- to single-domain state transition occurred with the formation of an intermediate nanodomain state. After removing the electric field, domain configurations reappeared. Selected area electron diffraction during electrical poling gave no indication of any structural changes as for example reflection splitting. Rather, a contribution of the extrinsic effect to the piezoelectric response of the Ba(Zr0.2Ti0.8)O3-0.3(Ba0.7Ca0.3)TiO3was found to be dominant.open2

Influence of B-Site Disorder on the Properties of Unpoled Bi1/2Na1/2TiO3-0.06Ba(ZrxTi1-x)O3 Piezoceramics

The influence of B-site disorder on the dielectric, microstructural, and structural characteristics of unpoled, lead-free (Bi1/2Na1/2)TiO3-0.06Ba(ZrxTi1-x)O3 piezoelectric ceramics with x = 0.02, 0.10, and 0.15 was investigated. The low and medium doping level introduced a stabilization of polar nanoregions reflected in the shift of the dispersive permittivity anomalies to higher temperatures and the development of lamellar rhombohedral domains embedded in the prevalent tetragonal nanodomain matrix. For higher Zr level, the regions of lamellar domains remain, but the dielectric characteristics indicate a reduction in the previous stabilization effect. This behavior is rationalized by a reduction in the correlation length due to the increasing amount of nonpolar sample volume with increasing Zr addition