Amorphous solidification in submicron droplets of pure metals

Abstract

Many techniques have been developed for synthesis of amorphous materials. The most successful method used to form metallic glasses from melts has been to alloy pure metals with other elements in order to decrease the thermodynamic and kinetic driving force for crystallization. There are two common groups of alloying systems that form glass effectively; metal-metalloid alloys and intertransition metal alloys. These alloys would be readily solidified as an amorphous phase by splat quenching, metal spinning, or laser surface melting. In the 1970's, pure metals such as Cr, Fe, and Mn were made amorphous in thin film form by evaporation of metal vapors onto a very cold substrate (4 K). Recently, Kim, Lin, and Kelly discovered amorphous phases in rapidly solidified droplets of pure iron and alloys of iron and nickel. The submicron droplets of liquid metal were produced and cooled in free fright through a vacuum chamber.