Sunday November 27 2011 / Science & Technology
Blow it from the palm of your hand and it will float gently to the floor like a feather. Squish it between your fingers and it will bounce back to its original shape. But look closely at it and the tiny nickel framework of tubes will remind you of the considerably bigger beams that make up engineering masterpieces like the Eiffel Tower and the Golden Gate Bridge.
What is it? Nothing less that the world’s lightest material, which was unleashed earlier this month by HRL Laboratories who developed it in parnership with the California Institute of Technology and the University of California.
The new material redefines the limits of lightweight substances because of its unique ‘micro-lattice’ cellular architecture, which is (unimaginatively) called: Ultra-light metallic micro lattice.
Using an innovative fabrication process – a self-propagating photopolymer wave guide technique, if you must know – the architecture of the lattice can be easily modified to make a material that’s stronger and stiffer than foams and aerogels of the same density and which used claim the title of lightest substances in the world.
“The trick is to fabricate a lattice of interconnected hollow tubes with a wall thickness of 100 nanometers – a thousand times thinner than a human hair,” says lead researcher on the project Dr Tobias Schaedler in reference to the material that consists of 99.99% open volume with 0.01% solid.
"Our vision is to revolutionise lightweight materials by adopting principles of architecture into their design. If you look at the Eiffel Tower or Golden Gate Bridge, they're incredibly light and strong for their size by virtue of their architecture — the Eiffel Tower is taller and lighter than the pyramids because of its design."
"We want to achieve the same thing these modern buildings achieve by working on the structures of materials."
In addition to its ultra-low density, the material’s cellular architecture gives rise to unprecedented mechanical behaviour for a metal, including complete recovery from compression as well as an extraordinarily high energy absorption.
"Its energy-absorption capabilities might make it useful for acoustic-, vibration- and shock-damping,” says Schaedler. “If we want to, we can control the architecture on the millimeter, micrometer and nanometer scales, to design materials with tailored properties for specific applications.”
Still, the micro-lattice may yet be used for slightly grander purposes than just soundproofing your home studio; the research for the micro-lattice was conducted for the US Defence Advanced Research Projects Agency, and Schaedler duly adds: “We’re also envisioning applications in structural components such as in aerospace."
For more information, please visit www.HRL.com