ZHOU Chunming, ZHANG Jialiang, CAO Yue, SU Wenbin
(School of Physics, Shandong University, Jinan 250100, Shandong, China)
Abstract: Piezoelectric composites with 1-3 connectivity have attracted great attentions recently for the applications in ultrasonic transducers, such as biomedical imagers and industrial flaw detectors. However, piezoelectric temperature stability of the composites has rarely been reported in the literature, which is vital for practical applications. A commercially available PZT-43 ceramic was adopted to prepare 1-3 PZT/epoxy piezoelectric composite with an improved dice-fill method, whose room-temperature piezoelectric performances and electromechanical temperature stability were studied. This composite showed well-balanced overall performance, with thickness-mode electromechanical coupling coefficient (kt) of 0.65, dielectric loss (tanδ) of 0.019, coefficient (g33) of 46*10−3 Vm/N and acoustic impedance (Z) of 15.5 Mrayl. kt is very stable, with a change rate of less than ±3% in the common application temperature range from -30 ℃ to 100 ℃. Therefore, selecting a proper PZT ceramic is an essential precondition for the development of high performance piezoelectric composites.
Key words: 1-3 piezoelectric composites; PZT ceramics; electromechanical coupling coefficient; temperature stability