Metal Foam is Lighter Than Aluminum, Stronger Than Steel

Materials scientist Afsaneh Rabiei has developed a substance that is very lightweight, but stronger than a block of steel. And when placed under extreme pressure, it can absorb shock without shattering:

Rough traffic accident calculations show that by inserting two pieces of her composite metal foam behind the bumper of a car traveling 28 mph, the impact would feel the same to passengers as impact traveling at only 5 mph.[...]

The results are most striking when the material is tested in a lab. The test itself is exciting: a high-powered machine smashes a piece of steel foam straight down into the base plate of the machine, and then does the same thing with a piece of bulk steel.

When she examines the base plates under both samples, there’s a clear indentation left under the bulk steel sample, while the plate under the foam shows no indentation. The test shows how the foam absorbed the energy and protected the plate, while the steel simply transferred it to the base plate with no protection.

Among potential applications are orthopedic implants and body armor. In the links, you can find a video about the invention.

Link via Digg | Video | Image: Iran Daily