INTO THE FOURTH DIMENSION

An Australian institute is designing and printing objects that can shapeshift after they're made. Forget next-gen - Denise Cullen reports from the next dimension.

-  Denise Cullen

Materials scientist Liwen Zhang dips a pair of tweezers into a beaker of iced water (0°C) and plucks out a small grey object the shape of a lotus flower in full bloom.

He plunges it into a second beaker filled with tepid water (15°C). When Zhang retrieves it after a few seconds, the flower has flattened out to form a disc-shaped like a picture-book sun.

This demonstration, unfolding during my of The University of Queensland's Australian Institute for Bioengineering and Nanotechnology (AIBN), may seem simple, but it's an example of the remarkable and pioneering field of four-dimensional (4D) printing.

This emerging process which is how the shapeshifting object was made - has profound implications for a range of fields, from manufacturing and medicine to fashion and furniture.

The AIBN's Group Leader, Senior Research Fellow and NHMRC Emerging Leadership Fellow, Ruirui Qiao, explains that 4D printing is an extension of three-dimensional (3D) printing.

"3D printing is the technology 4D printing is just the process," she says. "The fourth dimension is actually time these structures can change their shape over time."

There's no such thing as a 4D printer. Rather, items assume the mantle of 4D by the way in which specific ingredients are combined to give the finished product useful qualities and abilities. Using a readily available 3D printer purchased for about $300, Qiao and Zhang turn out solid objects with the capacity to morph into different forms when exposed to stimuli such as heat, water or light.

4D printing is already in use in the medical device sector to create coronary stents, artificial muscles and other devices that adapt and change shape inside the body.