Dimension dependence of thickness resonance behavior of piezoelectric fiber composites

Aperiodic arrangement PZT5 fiber/epoxy resin 1-3 piezoelectric composites were fabricated by viscous polymer processing. The impedance spectra were used to discuss the radial and thickness resonance models dependent on the size of 1–3 composites. The aspect ratio t/d is found critical to the resonance parameters. As the aspect ratio t/d reducing, the mechanical quality factor Qm would decrease, the frequency constant Nt and the acoustic impedance Z increasing. In general, the composites showed nearly a pure thickness mode with high anisotropy coefficient (kt/kp ∼ 1.38–2.75) and low acoustic impedance (Z ∼ 9.5–11.7 Mrayl) superior to those of monophasic PZT5 materials that have potential applications in medical ultrasonic transducers.