World’s lightest material touted by US researchers

With a density of just 0.9mg/cc, about 100 times lighter than Styrofoam, the new material has a micro-lattice cellular architecture and is made up of 99.99% air. According to lead researcher Dr Tobia Schaedler, from the University of California, it demonstrates unprecedented mechanical behaviour for a metal, including complete recovery from compression exceeding 50% strain and remarkably high energy absorption. "The trick is to fabricate a lattice of interconnected hollow tubes with a wall thickness 1,000 times thinner than a human hair," Dr Schaedler said. "Materials actually get stronger as the dimensions are reduced to the nanoscale. Combine this with the possibility of tailoring the architecture of the micro-lattice and you have a unique cellular material." Developed for the Defense Advanced Research Projects Agency, the researchers believe the novel material could be used for battery electrodes and acoustic, vibration or shock energy absorption. William Carter, manager of the architected materials group at HRL Laboratories, compared the metal to larger, more familiar edifices: "Modern buildings, exemplified by the Eiffel Tower or the Golden Gate Bridge, are incredibly light and weight efficient by virtue of their architecture. We are revolutionising lightweight materials by bringing this concept to the nano and micro scales."