Evaluation of the properties of 1-3 piezocomposites of a new lead titanate in epoxy resins

By using a new calcium-modified lead titanate ceramic with a near-zero planar coupling coefficient, a series of 1-3 piezocomposite samples was fabricated with a dice-and-fill technique. The ceramic rods were approximately 0.10 mm in size, and the percent of ceramic loading varied from 10 to 30%. Two epoxy resins with different glass transition temperatures and moduli were used. The dielectric properties and the piezoelectric dh and gh coefficients of the composites were measured as a function of pressure and temperature and were found to exhibit little variation, but 10-25% lower than theoretical predictions. A prototype hydrophone made from one of the piezocomposite samples was tested to show a constant free-field voltage sensitivity of -201 dB re V/μPa from 100 Hz to 6 kHz.