In each grain, the atoms form an orderly lattice. The grain boundaries are one example of a crystalline defect. Example of an amorphous structure. The atoms are arranged in a random fashion, similar to their arrangement in the liquid state. Amorphous metals, also known as metallic glasses, have existed in thin ribbon form since the 1960's.
Metallic glasses differ from conventional metals in that they lack crystalline structure.
The atoms in the amorphous structure are randomly arranged, like in a liquid, rather than sitting on a repeatable, orderly lattice. This lack of crystalline structure means that metallic glasses also lack crystalline defects, such as grain boundaries and dislocations. Because the equilibrium structure for a metal alloy is always crystalline, amorphous metals can only be produced by rapid cooling from the liquid state. The resulting ribbons and wires are used extensively as transformer cores and magnetic sensors, but the small dimensions limit the structural applications of the material. While there are numerous potential structural uses for these alloys, little is know about their mechanical properties and the micromechanisms of failure.