Lasers turn cement into liquid metal

By Doug Gross, CNN

Not all scientists compare themselves favorably to the lead-to-gold alchemists of King Arthur's day.

Then again, not all scientists say they've figured out a way to zap cement with a laser and turn it into metal.

Researchers at the U.S. Department of Energy's Argonne National Laboratory announced this week that they have unraveled a formula to do just that. The discovery, they say, opens up cheap, common cement as a material that could be used in the electronics world to make things like computer chips or thin films and other protective coatings.

“This new material has lots of applications, including as thin-film resistors used in liquid-crystal displays -- basically the flat panel computer monitor that you are probably reading this from at the moment,” said Chris Benmore, a physicist from Argonne who worked with a team of scientists from Japan, Finland and Germany on the project.

    The metallic glass material that results from the process has both better resistance to corrosion than regular metal and is less breakable than regular glass, the researchers say.

    This change demonstrates a unique way to make metallic-glass material, which has positive attributes including better resistance to corrosion than traditional metal, less brittleness than traditional glass, conductivity, low energy loss in magnetic fields, and fluidity for ease of processing and molding. Previously, only metals have been able to transition to a metallic-glass form.

    In the process, researchers melted mayenite -- a component of cement made of calcium and aluminum oxides -- at temperatures of 2,000 degrees Celsius using a carbon dioxide laser beam. By keeping the piping hot material in an aerodynamic levitator, they were able to keep it from touching the sides of its container until it cooled into a glassy state.

    Until now, only metals were able to be melted into a metallic-glass form. They say their discovery could lead to finding other materials that can be turned into semi-conductors.