| Polymer matrix piezocomposites composed of piezoelectric ceramic and polymer is a new function material. It takes advantage of each constituent, such as high flexibility which will favorable to make any shape, low density and low acoustic velocity, so it can be matched with water, biology tissue and so on. Furthermore, it has low dielectric constant and high electromechanical coupling coefficient, which will be favorable to increase the piezoelectric hydrostastic figure of merit, the sensitivity of transducers and pyroelectric figure of merit. The properties of piezoelectric composite can be classfied as sum, combination and product properties, so it will be possible that some new properties will occur in the piezocomposite. The properties of piezocompsite depend on the properties of each constituent and connectivity primarily, so it can be tailored to meet various demands such as underwater ultrasonic, electroacoustic, ultrasonic transducers and so on. The poiezoelectric composite are attracting a great deal of attention.In this paper, the aim is focused on design, including experimental and theoretical design, and analysis to mechanism of piezocomposite. The main results and conclusions are as following:1. 1-3 PZT/epoxy piezocomposite is prepared by myself. It is founded that the properties and lateral resonant mode depended on the properties of polymer, PZT volume fraction and aspect ratio of ceramic pillar. The optimized condition is obtained: the ceramic volume fraction is between 0.3 to 0.5, and the aspect ratio is less than 1.2. A general analytical expression of pyroelectric coefficient of 0-3 piezocomposite is obtained when several effects, such as the interaction between particles, the property of polymer, polarized degree of constituent and polarized states, are considered. Compared with effective medium theory, it is founded that the results...
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