ASA 128th Meeting - Austin, Texas - 1994 Nov 28 .. Dec 02

4aEA4. 1--3 Piezocomposite transducer materials for commercial underwater applications.

Victor Murray

Fugro-UDI Ltd., Bridge of Don, Aberdeen, Scotland AB23 8JW, United Kingdom

Fugro-UDI Limited has gained several years experience in developing piezo-composite materials for use in underwater imaging sonars operating in the frequency range 100--500 kHz. A substantial amount of this work has concentrated on multielement arrays for military applications such as mine counter measures. The low mechanical quality factor (Q[sub m]) and high electro-mechanical coupling coefficient (K[sub t]) of the material has provided wideband and efficient transducer materials. These parameters and others such as dielectric constant and electrical impedance can be tailored by varying the type and quality of both the ceramic material and polymer phase within the piezocomposite device. This has contributed to reducing the development and manufacturing costs of piezocomposite transducers. This presentation will discuss the various transducers developed by Fugro-UDI for commercial applications ranging from simple echo-sounder transducers, to sidescan transducers, through to multielement arrays for electronically scanned sonars. Sensitivities and beam patterns for piezocomposite devices will be compared with their ceramic counterparts. Other important transducer parameters such as pressure and temperature dependence of the piezocomposite materials will be presented.