Thickness and temperature dependence performances for single crystal composites by different polarization conditions.

Alternating current polarization (ACP) has been demonstrated to enhance the performance of 1-3 piezoelectric single crystal composites (PSCCs), compared to direct current polarization (DCP). However, the scaling effect and temperature stability of PSCCs under different polarization modes, which are of significance to practical applications, have rarely been studied. Here, we compared and analyzed the thickness and temperature-dependent properties of PSCCs under ACP and DCP. The results indicated that ACP PSCCs have improved piezoelectric, electromechanical coupling, and dielectric properties. There were scaling effects for PSCCs with thickness below 400 μm. Compared to high-thickness PSCCs, the piezoelectric coefficient (d33), free dielectric constant ( ε 33 T ε 0 ) as well as thickness electromechanical coupling factor (kt) of low-thickness samples were inferior and the corresponding performance enhancements under ACP were also relatively low. In contrast, the clamped dielectric constant ( ε 33 S ε 0 ) did not show significant thickness correlation. As for temperature stability, all performances of PSCCs improved with increase in temperature and the performance enhancement with temperature change was not dependent on the polarization conditions. This work provides reference significance of selecting appropriate polarization for PSCCs, thus benefiting the design and preparation for transducers. [ABSTRACT FROM AUTHOR]