Offering some potentially game-changing applications for engineering, a team of researchers has forged a new type of ultra-light aluminium.

Aluminium has become synonymous with many major industries, such as aircraft manufacturing where the light metal reduces a significant amount of weight compared with other heavier metals.

But what if we could make it even lighter?

That was the mission of a team of researchers at Utah State University that has published a paper in The Journal of Physical Chemistry C revealing a new type of aluminium that is significantly lighter and could have major ramifications for engineering.

Typically, if you put an aluminium spoon into a bowl of water, the spoon will sink to the bottom as it is denser than the water. Using an ultra-light crystalline form of aluminium, however, the team was able to demonstrate that its new material was capable of actually floating on water.

The breakthrough was made with a crystal lattice, in the form of a diamond, where every carbon atom was substituted with an aluminium tetrahedron.

When the team calculated its weight, they were amazed to find that it had a density of only 0.61g per cubic centimetre, in contrast to conventional aluminium’s 2.7g per cubic centimetre.

Still many unknowns

“That means the new crystallised form will float on water, which has a density of 1g per cubic centimetre,” said Alexander Boldyrev, who was involved in the research.

He added that the breakthrough, if further developed, could open a whole new realm of possible applications for the non-magnetic, corrosive-resistant, abundant, relatively inexpensive and easy-to-produce metal.

“Spaceflight, medicine, wiring and more lightweight, more fuel-efficient automotive parts are some applications that come to mind,” Boldyrev said.

“Of course, it’s very early to speculate about how this material could be used. There are many unknowns. For one thing, we don’t know anything about its strength.”

The team believes this breakthrough will pave the way for greater, future discoveries for materials science as it is an example of using a known structure to design a new material.