DEVELOPMENT OF NOVEL TRANSDUCER MATERIALS

换能器用PZT-5H等传统压电材料 可能不适用于甚高频换能器和阵列制造。 此外，更好的压电材料与更高的耦合 系数和可变介电常数，允许更宽的 需要带宽和更灵活的换能器设计 改进了传统线阵的性能，以及 多维阵列的发展。在这个项目中，细粒 晶粒尺寸较小的单晶弛豫材料PZT 如PZN-PT，其耦合系数远高于 将制备和改进PZT-5H用于甚高频线阵的制作。 此外，通过溶胶-凝胶法制备的1-3纤维复合材料将 是为甚高频单元件换能器开发的。的潜力 这些材料已经被证明是在 制备的超声换能器的带宽和灵敏度 这些材料与由PZT-5H制备的材料相比， 类似的情况。

Conventional piezoelectric materials such as PZT-5H for transducer may not be suitable for VHF transducer and array fabrication. Moreover, better piezoelectric materials with higher coupling coefficient and variable dielectric constant allowing for wider bandwidth and more flexible transducer design are needed for the improvement of conventional linear array performance as well as the development of multidimensional arrays. In this project, fine grain PZT which has smaller grain size and single crystal relaxor materials such as PZN-PT which has a much higher coupling coefficient than PZT-5H will be prepared and improved for VHF linear array fabrication. In addition 1-3 fiber composites prepared via a sol-gel process will be developed for VHF single element transducers. The potential of these materials has been demonstrated by the better performance in bandwidth and sensitivity of ultrasonic transducers prepared from these materials in comparison to those prepared from PZT-5H under similar conditions.