Investigation in to novel piezoelectric materials and manufacturing methods for sonar transducers

The overall objectives are aimed at using new piezoelectric materials and fabrication methods to enhance high power sonar over a wide frequency band.

Ultrasonic transducers typically comprise active piezoelectric materials couples with a number of ancillary passive materials to control the mode of vibration and provide acoustic matching to the load and damping at the rear face.

The project is two-fold; in order to address the active component within a sonar transducer design textured versions of the Single-Crystal PMN-28PT are key to achieving improved properties by mechanically aligning the jumbled crystal domains rather than align them through natural crystal growth which is far more expensive process. This gives 'k33' and 'k31' mode couplings for the Textured form of PMN-28PT, relative power density and relative at a fraction of the cost per volume when compared to the equivalent Single-crystal material. Repeatable scaling of laboratory process is yet to be achieved, but combining the well-known commercial tape casting process with templated grain growth (TGG) enables the production of high-performance flat plates and cylindrical shapes at a fraction of the cost of a single crystal. Textured material promises to be a significant part of the unfolding piezoelectric ceramic technology revolution.

The problem space for the passive components of the design will be explored using additive manufacturing technique that are common in contemporary rapid prototyping techniques such as laser sintering and 3D printing. This will allow passive component designs to move away from cylindrical or rectilinear morphologies that are common in subtractive manufacturing and allow for more esoteric design strategy