Abstract:
New piezoelectric 1-3 composite materials containing ceramic rods embedded in a polymeric matrix have been shown to exhibit excellent piezoelectric properties for sonar transducer applications. A 4x10 hydrophone array was recently fabricated by using injection-molded 1-3 piezocomposites of PZT-4 ceramic and a polyurethane resin. The array panel was evaluated in the Anechoic Tank Facility at USRD in Orlando, FL. Free-field voltage sensitivity, directivity pattern and interelement phase relationship were determined as a function of temperature, pressure, and frequency (up to 200 kHz). Element-to-element uniformity within the array was observed. Pressure and temperature stabilities of the panel were also demonstrated up to 7 MPa at 3 (degrees)C. The ability of this 1-3 composite array to detect low-sound pressure levels was also shown in comparison with similar arrays of other materials such as lead titanate ceramic and piezorubber composite. These test results indicate that 1-3 piezocomposite is a promising candidate for application in high-frequency sonar transdu-cers. [Work supported by ONR.]