Temperature-Dependent Properties of a 1-3 Connectivity Piezoelectric Ceramic-Polymer Composite

Abstract

In this work, the 1-3 connectivity piezoelectric ceramic-polymer composites have been fabricated by a viscous-polymer processing, where 0.90Pb(Zr0.52Ti0.48)O3-0.05Pb(Mn1/3Sb2/3)O3-0.05Pb(Zn1/3Nb2/3)O3 (PZT-PMS-PZN) fibers with 0.5 volume fraction were aligned in epoxy matrix. The sintered PZT fibers, with average diameter of 300 μm and aspect ratio (height/diameter) higher than 3, all showed a pure perovskite phase structure and highly dense morphology. The dielectric, piezoelectric, ferroelectric properties and the vibration modes of the 1-3 composites were measured and demonstrated in comparison with that of the monolithic piezoelectric ceramics. The results confirmed that the 1-3 composites possessed a low acoustic impedance (Z) of 13 MRayl and a high thickness coupling coefficient (kt) of 0.59, in addition, only single thickness vibration mode with the resonance frequency over 1.5 MHz was observed. With temperature elevation, the properties including dielectric constant ϵr, kt, the ratio of kt to kp (kt/kp) and the acoustic impedance (Z) increase, while the planar electromechanical coupling coefficient (kp) show opposite temperature dependence. Under test temperature of 100°C, the 1-3 composites still present excellent temperature stability with increased kt/kp ratio up to 3.6. The researches on temperature-dependent properties of the 1-3 composites are critical for improving its applications in various environments.