In many applications such as hydrophone and ultrasonic transducers, materials with large piezoelectric anisotropy are preferred in order to suppress tfae interfering signals from lateral modes. It has been shown that piezoelectric anisotropy can be significantly improved by structure design. For instance, for a radially poled cylindrical tube, the effective transverse piezoelectric response can be tuned to zero. In this work, the effective piezoelectric responses of lead zirconate titanate (PZT) and lead magnesium niobate-lead titanate (PMN-PT) ceramic cylindrical tubes were studied. Large piezoelectric anisotropy with a high effective uniaxial coefficient has been obtained for both materials. It has been shown that near zero effective d,t can be achieved for a PZT tube with a proper dimension ratio of r0/R0, where r0 and R0 are inner and outer radii of the tube, respectively. While for a PMN-PT tube, the effective piezoelectric responses can be tuned by the ratio of r0/R0 as well as the bias Meld because the induced piezoelectric coefficients d33 and d3l and their ratio |d33/d31| are all functions of the bias field.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics