New materials can drive us into a changeable future

Sahar in the lab

What if your car or aeroplane could adapt its shape depending on the conditions to become more aerodynamic, and therefore more fuel-efficient?

This could well be the future of the automotive and aerospace industries – using metals that can change their shape to improve performance, says Sahar Naghashian, an Associate Research Fellow at Deakin University.

She’s working on adaptive composites: lightweight, strong materials capable of reversible shape-changing.

Smart car spoilers that pop up only when cars are driving fast are one example of where the technology would be beneficial, Sahar says. Such spoilers would still help a car grip the road at high speeds, but would avoid creating unnecessary drag when driving slower.

Another potential use, inspired by birds’ flight, is aeroplane wings that change their shape based on flight conditions. In fact, the concept of shape optimisation could be applied to any objects moving through any fluid environment.

Adaptive composites are made from a composite host and thin wires of shape memory alloys — they bend when activated by heat and unbend when cooled.

“The shape change is achieved through heating, which can be done by simply passing a current through the wires. In special cases, the required heat may also be provided by the environment temperature without any further manipulation,” Sahar says.

“My focus is to understand the limits, potential and possibilities of this bending movement.

“Improved aerodynamic properties in vehicles will reduce fuel consumption, reduce the carbon footprint, and can also contribute to noise reduction. In general, this research can lead to manufacturing greener vehicles.”

Sahar presented her research at Fresh Science Victoria 2015.

Fresh Science is a national program that helps early-career researchers find and share their stories of discovery. Over 30 early-career researchers nominated for Fresh Science Victoria, which was held at Scienceworks (training), Melbourne Museum (schools forum) and the Kelvin Club (public challenge event).

Fresh Science Victoria was supported by Museum Victoria, Bio-Medical Research Victoria and the Office of the Victorian Lead Scientist.

Sahar Naghashian, Deakin University, +61352273408; saharn@deakin.edu.au