" Amorphous steels may revolutionize the steel industry," says Joseph Poon, professor of physics at U.Va. New alloys come from modifying a previous version of amorphous steel, DARVA-Glass 1. Poon's team includes Gary Shiflet, professor of materials science, and engineering and materials physicist Vijayabarathi Ponnambalam.
One version, DARVA-Glass 101, could be used for making ship hulls, lighter automobiles, tall buildings, corrosion-resistant coatings, surgical instruments, and recreational equipment. The scientists say the material could be commercially available in three to five years.
According to Poon, researchers have been trying for years to make amorphous steel in sizes large enough for practical use. U.Va researchers have produced large-size amorphous steel samples by adding a small dose of a rare-earth element or yttrium to DARVAGlass 1. The researchers believe that the large size rare earth or yttrium atom causes destabilization of the competing crystal structure wherein the significant atomic level stress can lead to the formation of the amorphous structure.
The amorphous steel can reportedly be machined or manipulated like a plastic. "It can be squeezed, compressed, flattened, and shaped," says Poon. "But although extremely strong, in its current state it is brittle. We need to toughen the material more," he says.
Amorphous alloys are of interest to the Navy for making nonmagnetic ship hulls, particularly for submarines. Conventional hulls are detectable by their magnetic fields. Poon's amorphous steel is nonmagnetic. This will potentially make ships invisible to magnetism detectors and mines that are detonated by magnetic fields. In addition, the new material may be useful for producing lighter but harder armorpiercing projectiles.
The amorphous steel project is sponsored by DARPA's (Defense Advanced Research Projects Agency) Structural Amorphous Metals Program. Liquidmetal Technologies Corp. Lake Forest, Calif. (www.liquidmetal.com), owns an exclusive license to the amorphous steel.