Influence of water-to-cement ratio on piezoelectric properties of cement-based composites containing PZT particles

To enhance piezoelectric properties, the effect of water-to-cement ratio (w/c) on 0-3 type cement-based composites containing 30-70% lead zirconate titanate (PZT) ceramic as the inclusion is investigated, where the w/c varying from 0% to 20%. Dominate factors that affect the facilitation of polarization and piezoelectric properties are also discussed. Results indicate that the composites with a higher w/c have higher values of porosity and dielectric loss, resulting in longer trigger times during the polarization. To facilitate polarization, the dielectric loss and the resistivity of the composites had better be less than 0.75 and 100 k Omega-m, respectively. Piezoelectric cement with a favorable w/c can improve its piezoelectric properties. The optimum w/c of the composites for 50% PZT (P50) and 70% PZT (P70) to obtain the highest piezoelectric strain factor d 33 and relative dielectric constant epsilon(r) values are 10% and 5%, respectively, and the values at the age of 100 days are d(33) = 133 pC/N and epsilon(r) = 878 for P50, and d(33) = 143.1 pC/N and epsilon(r) = 890 for P70. Moreover, the thickness electromechanical coupling coefficient (K-t) strontgly depends on w/c, and the effect of temperature treatment on K-t becomes prominent with the increase in w/c. (C) 2019 Elsevier Ltd. All rights reserved.