22 November 2011

World's Lightest Material is a Metal

Engineers have developed the world's lightest material. It is about one hundred times lighter than Styrofoam(tm) and is made from the metal, nickel.

The joint team from the University of California, Irvine, HRL Laboratories and the California Institute of Technology published their research in latest edition of Science. Dr. Tobias Schaedler of HRL is the lead author.

The material is made out of tiny hollow metallic tubes arranged into a micro-lattice - a criss-crossing diagonal pattern with small open spaces between the tubes. Dr. Schaedler says, "The trick is to fabricate a lattice of interconnected hollow tubes with a wall thickness 1,000 times thinner than a human hair,"

The material's design allows complete recovery from compression and very high energy absorption. After being compressed to just 50% of it's thickness, the material regained 98% of its original height and resumed its original shape.

Video: Actual material being compressed to 50% of its thickness

According to their publication, "These materials are fabricated by starting with a template formed by self-propagating photopolymer waveguide prototyping, coating the template by electroless nickel plating, and subsequently etching away the template..."

Compared to aerogels (the world's lightest solid), the material's design is ordered in nature because of the lattice. Aerogels are formed with random cellular structures making them "less stiff, strong, energy absorptive or conductive than the bulk of the raw materials that they are made out of..".

The manager of the architected materials group at HRL, William Carter, compared the new material to larger, familiar structures, "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 revolutionizing lightweight materials by bringing this concept to the nano and micro scales."

This new material can be used for thermal insulation, battery electrodes, shock absorbers, and sound dampeners.