Theoretical modelling of frequency dependent elastic loss in composite piezoelectric transducers.

The large number of degrees of freedom in the design of piezoelectric transducers requires a theoretical model that is computationally efficient so that a large number of iterations can be performed in the design optimisation. The materials used are often lossy, and indeed loss can be used to enhance the operational characteristics of these designs. Motivated by these needs, this paper extends the one-dimensional linear systems model to incorporate frequency dependent elastic loss.

A theoretical analysis of a piezoelectric ultrasound device with an active matching layer.

This paper investigates the use of magnetically active materials in the matching layer of a piezoelectric transducer. This then allows the performance of the device to be dynamically altered by applying an external field. The effect that this new matching layer has on the performance of a typical device is theoretically investigated here.

Improving the thermal stability of 1-3 piezoelectric composite transducers.

The effect of temperature on the behavior of 1-3 piezoelectric composites manufactured using various polymeric materials was assessed experimentally through electrical impedance analysis and laser vibrometry. Device behavior varied with temperature irrespective of the polymer filler. Most significant changes in the piezoelectric composites were recorded around the glass transition temperature (Tg) of the polymer; movement to lower fundamental resonant frequencies and higher values of electrical impedance minima were observed at higher temperatures.