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Material Used to Provide High Resolution Images

Morgan Technical Ceramics (MTC) introduces its Piezoelectric composite components for use in a wide range of undersea applications, including conformal sensors and detectors for ships and deployable vehicles, as well as in large-area arrays for undersea exploration. Components manufactured with MTC’s Piezocomposite materials offer significant improvements over traditional transducer materials.

MTC’s Piezocomposite material consists of a Piezoelectric ceramic in an electrically-inactive polymer matrix. It is specifically formulated with high coupling values and high dielectric properties. Combining the Piezoelectric ceramic with polymer filler results in a material with an overall density that better matches the medium through which the sound waves travel. This results in lower acoustic impedance, higher efficiency and energy transfer through water, and reduced lateral mode coupling within the acoustic device. The arrays can be phased electrically, going from element to element, in a solid state, with no moving parts.

The Piezocomposite materials are being used in many different undersea vessels, including submarines and other manned vessels, as well as autonomous underwater vehicles (AUVs), and remotely operated underwater vehicles (ROVs). AUVs are robots that travel underwater, and are typically used to conduct hydrographic surveys, and look for airplane wreckage, shipwrecks, and antiquities. They are also widely used for military purposes, including mine hunting. The non-autonomous ROVs, powered from the surface by an operator or pilot using a control umbilical, are typically used for undersea exploration, checking on the condition of undersea pipelines, using optics, or other ultrasound modalities. Side-scan sonar using the Piezocomposites can obtain extremely high resolution images, at frequencies ranging from 200 to about 800 kilohertz (kHz).

The Piezocomposite materials reduce the cross coupling that typically occurs between different modes in the ceramic of conventional transducers, enabling sonar components to respond more precisely and predictably. In addition, components manufactured with MTC’s Piezoelectric composite materials reduce spurious activity, offering higher transmit and receive efficiency. They also provide lower acoustic impedance and improved transducer bandwidth compared to those made only of conventional Piezoelectric ceramics.

Unlike traditional side-scan arrays, which must use various attenuative materials to suppress channel-to-channel interference or cross coupling, the polymer fill in the Piezocomposites has attenuating properties that are maximized for each design, and does not need further suppression. Also, the traditional transducer manufacturing process involves placing thin bars of PZT material in a linear array pattern, much like the tines of a comb. Moving to Piezocomposite materials allows fabricators to make one long plate of material that can be electroded with an array pattern, which greatly simplifies the transducer manufacturing process as well as improving their acoustic signal. The transducers exhibit better resolution, and a reduction of cross-talk (element to element interference). In addition, Piezocomposites tend to have less mass, and this weight reduction can be a significant benefit. The elimination of complexity in manufacturing can lower costs compared to traditional side-scan transducers.

MTC offers Piezoelectric composites in 1-3 and 2-2 architectures, in sizes up to 3” x 2” and frequencies from 100 kHz to 12 MHz. Piezoelectric volume fractions can be tailored for any application to enhance transmit and receive response rates. The Piezocomposites offer increased design flexibility, because they can be thermoformed to conform to curved, complex geometric surfaces to which conventional Piezoceramic materials often cannot be shaped. MTC offers Piezoelectric composites in both standard and custom materials, including Types I, II, VI and Single Crystal Lead Magnesium Niobate-Lead Titanate (PMN-PT).

MTC works with customers to integrate Piezocomposites into undersea applications on many levels. Our experts can outline design concepts, construct assemblies, or use finite element analysis to model a visual representation of the material in the design and development of our customer’s product.

For further information please go to www.morganelectroceramics.com or contact +44 (0) 2380 444811 for European/Asia enquiries or +1 (440) 232 8600 for US and Australasia enquiries.