Local icosohedral order in metallic glasses
(Phys.org) —Metallic glasses are essentially a frozen, supercooled liquid. They are amorphous metals, often alloys, which are non-crystalline and therefore have a highly disordered atomic arrangement. They are true glasses in the sense that they soften and flow upon heating. The ability to easily process these materials has led to their use in many products, like for example, those made by injection molding. Over a half century ago, it was proposed that metallic liquids, and perhaps even glasses possess icosohedral clusters. Despite attempts using neutron or x-ray scattering to reveal this icosohedral order, only average structural information has been obtained. A new paper published in Science, describes development of an Angstrom-beam electron diffraction (ABED) method which is able to probe local atomic structure with a 0.4 nm electron beam. The authors were able to characterize local icosohedral order in ZrPt (Zr80-Pt20)glass, and found that it is in close agreement with...