Thursday, November 24, 2011
How to create a light material: The matter used to create the material should be light. The percentage of space inside the material should exceed the matter. Any shape the matter is molded into should be hollow to decrease the weight further. But, all the above actions shouldn’t affect the stability and strength of the created material.
The substance 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. The trick employed is to fabricate a lattice of interconnected hollow tubes with a wall thickness 1,000 times thinner than a human hair.
Characteristics of the NEW World’s Lightest material:
1) The material created has exceptionally low density -- a density of 0.9 milligrams per cubic centimetre. To get an idea of how low the density of this newly created material is, a comparison with lightest material known to humans as of now will be adequate. By comparison the density of silica aerogels - the world's lightest solid materials - is only as low as 1.0milligrams per cubic cm.
2) Ample Spaces: The metallic micro-lattices have the edge because they consist of 99.99% air and of 0.01% solids.
3) The material derives its strength from the ordered nature of its lattice design. For instance, we known that hollow tubes, ‘I’ shaped cross sections, arches and diagonals give strength to a structure; and hence are normally used in modern buildings, sometimes called ‘Larger low-density structures’. The new material thus compares to the larger low-density structures.
By contrast, other ultralight substances, including aerogels and metallic foams, have random cellular structures. This means they are less stiff, strong, energy absorptive or conductive than the bulk of the raw materials that they are made out of.
4) Very Robust and resilient(comes back to its original shape once the pressure is removed): To study the strength and resilience of the material, the scientists compressed the material until it was half as thick. After removing the pressure the substance recovered 98% of its original height and resumed its original shape.
The first time the stress test was carried out and repeated the material became less stiff and strong, but the team says that further compressions made very little difference. The reason for this is that -- Materials actually get stronger as the dimensions are reduced to the nanoscale, informed the scientists.