Performance enhancement of 1–3 piezoelectric composite materials by alternating current polarising

Abstract

The performances of 1–3 piezocomposite materials under various poling conditions were compared and analysed. The dielectric, piezoelectric, and electromechanical properties of 1–3 piezocomposite materials were studied with variations in the electric field amplitude (Ep), poling frequency (f), and number of cycles (C). It was found that the piezoelectric coefficient (d33), free dielectric constant (ε33T/ε0), and electromechanical coupling factor (kt) of 1–3 piezocomposite materials exhibit an increase of 21.4%, 13%, and 10.7%, respectively, under the optimum alternating current poling (ACP) condition (f = 1.25 Hz, Ep = 2 kV/mm, C = 16), compared with that of the samples poled using the direct current polarisation (DCP) method. The studies of the domain pattern indicate that the performance enhancement originates from the remarkable regularly striped domain structure and high domain wall density in ACP-poled samples. Our results suggest that the ACP method is effective in enhancing the performance of composite piezoelectric materials, which possess great benefits and potential for application in acoustic/medical transducers.