What do car parking sensors, ultrasound scanners and musical birthday cards have in common? They all rely on piezoelectric materials to work.
Working in high temperatures
Piezoelectricity is an electric charge that accumulates in certain solid materials in response to applied mechanical stress and vice versa. By applying a voltage the material then contracts and expands. Piezoelectric materials have been in widespread and ever-increasing use since the 1960s but there has not been any major improvement in their properties or performance. One problem is that conventional piezoelectric materials have limited strength and only work in temperatures of up to 200°C, making them unsuitable for high temperature applications.
Aiming to transform the operating performance, stability and durability of piezoelectric materials, Dr Tim Stevenson, Professor Andrew Bell and Dr Tim Comyn have been developing piezoelectric sensors and actuators robust enough to work efficiently at temperatures of 450°C or more. Realising the potential for the application of new advances in this area they formed a spin-out company in 2011, Ionix Advanced Technologies, dedicated to working on this new material.
Opening up new applications
Ionix initially investigated developing sensors and actuators to work inside jet engines at temperatures of up to 450°C. As developing components for use in jet engines can take 10-15 years the team are also looking at other applications for their sensors.
The team has found potential applications in the nuclear and chemical industries, oil and gas exploration as well as aviation, For example one project has led to the development of a sensor which monitors the reliability of components in superheated steam systems. It is anticipated that this sensor could be adopted by a range of markets, from large scale energy plants through to public buildings such as hospitals. This according to professor Bell gives them a competitive advantage over conventional material.
For example, a computers memory uses components that need cooling by a fan. Using material that can work efficiently at higher temperatures, removing the need for constant cooling, would result in a reduction in energy use another useful side effect of the technology. The material is multi-functional and has the scope and potential for many new applications, only limited by imagination, he added.