Nov 11, 2004 - Scientific American
CHEMICALS AND MATERIALS
Joseph Poon and Gary J. Shiflet
Poon, professor of physics, and Shiflet, professor of materials science, University of Virginia
Created amorphous steel that could strengthen skyscrapers and armor-piercing rounds.
The strength of conventional steel is limited by defects that inevitably pop up in the crystalline organization of its atoms. Joseph Poon and Gary Shiflet and their colleagues devised amorphous steel that lacks those defects because it has randomly arranged molecular bonds. The resulting metal has triple the strength of its crystalline counterpart and better corrosion resistance. Although scientists have created amorphous alloys in the past, Poon and his team reported in the May 2004 Journal of Materials Research a way to make amorphous steel in bulk. The secret was adding the element yttrium, which discourages crystallization as the molten steel solidifies. The metal can then be cast in molds or shaped in the same way plastic can. Separately, researchers at Oak Ridge National Laboratory also reported making amorphous steel in bulk. Intriguingly, both steels are nonmagnetic, which has raised the U.S. Navy's hopes of using the material in submarine and other hulls that could evade magnetic sensors.