Electromechanical properties of barium titanate-polyvinylidene fluoride cement-based composites

In this study, 40-60 vol% barium titanate (BT) piezoelectric ceramic particles, Portland cement, and polyvinylidene fluoride (PVDF, 0-7 vol%) were used to fabricate 0-3 BT cement-based composites. The electromechanical coupling factor (k) and the mechanical quality factor (Q(m)) of the composites were investigated. Increasing BT and PVDF contents led to a decreased impedance of the composite. Moreover, the impedance peak detected was found to shift to a lower frequency. Broaden impedance peak can be observed when PVDF content increased. The electromechanical coupling factor of thickness mode (k(t)) and planar mode (k(p)) increased with increasing BT and PVDF contents. The highest values for kt (16.74%) and k(p) (16.94%) were found in the composite with 60 vol% BT and 5-7 vol% PVDF. The composite with no PVDF has a higher Q(m) value than composites with PVDF. The lowest Q(m) value can be observed at 3 vol% PVDF with all BT content. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

The study showed that increasing BT and PVDF contents in the composites resulted in decreased impedance and increased electromechanical coupling factor. The composite with 60 vol% BT and 5-7 vol% PVDF had the highest values for k(t) and k(p). No PVDF composite had a higher Q(m) value compared to those with PVDF, with the lowest Q(m) value observed at 3 vol% PVDF with all BT content.