Reticulated ceramic PZT/polymer piezoelectric composites for hydrophone applications.

摘要

eramic lead zirconate-titanate (PZT)/polymer piezoelectric composites easily fulfill many of the very demanding requirements necessary to produce an effective hydrophone and offer advantages over monolithic ceramics. They also provide improved sensitivity over solid PZT when fabricated in the proper configuration. One disadvantage of composites has been their high cost of manufacture. The primary objective of this project was to develop economical composite hydrophone and hydrophone array manufacturing methods using reticulated ceramic (ceramic foam) manufacturing technology. This forming process provided a suitable and modifiable geometry capable of being produced in large quantities at a reasonable cost.;Finite element techniques were successfully utilized to gain a basic understanding of the mechanisms involved in the performance of a piezoelectric composite. They provided quantitative evidence of the importance of the stress state in the surface of the ceramic and showed how this was controlled by both the amount and configuration of the ceramic phase.;An approach to production of piezoelectric composites and composite arrays was developed and implemented. The techniques employed standard reticulated ceramic processing methods with the exception of the use of distorted polyurethane foam substrates in processing of the reticulated ceramic PZT. A process for distortion of the foam suitable for production of large sizes and quantities was also developed and the technology transferred to a production facility at Hi-Tech Ceramics of Alfred, NY. Methods for producing large area conformable composite arrays using existing manufacturing techniques were also demonstrated. These methods were also transferred to Hi-Tech Ceramics' facility where they will be used to fabricate six deliverable prototype hydrophone arrays. The effects of ceramic content, reticulated ceramic pore size and distortion level, and polymer matrix type on the composite performance were investigated. It was found that the best hydrostatic charge coefficient,