Large thickness-mode electromechanical coupling and good temperature stability of 1–3 PZT/epoxy composites

Piezoelectric composites with 1–3 connectivity have attracted great attentions recently in ultrasonic transducers such as biomedical imaging and industrial flaw detection. However, data related to piezoelectric temperature stability of the composites can be rarely found in the literature. Thus, it is vital to study the piezoelectric temperature stability for practical applications. We chose a commercially available excellent PZT-51 ceramic to prepare a 1–3 PZT/epoxy piezoelectric composite with an improved dice-fill method and examined both its room-temperature piezoelectric performances and electromechanical temperature stability in this study. This composite shows the well-balanced overall performance with high thickness-mode electromechanical coupling coefficient k t of 0.73, large piezoelectric voltage coefficient g 33 of 65 × 10 −3 Vm/N, and moderate acoustic impedance Z of 13.8 Mrayl. Most importantly, k t is very stable with nearly no temperature dependence in the common usage temperature range from − 30 to 100 °C. This work indicates that selecting a proper PZT ceramic is an essential precondition for obtaining the excellent piezoelectric composites.