Amorphous aluminum alloys—synthesis and stability

Abstract

Recent innovations in metallic glasses have led to new alloy classes that may be vitrified and a re-examination of the key alloying factors influencing glass formation and stability. The new alloy classes are usually at least ternary systems and often higher order that can be grouped into two general categories. In one case, large, bulk volumes may be slowly cooled to the glassy state, which signifies a nucleation controlled synthesis. The other important class is represented by aluminum- and iron-based glasses that can be synthesized by rapid solidification processes such as melt spinning. These glasses are often called marginal glass formers that are synthesized under growth-controlled kinetic conditions. Glasses in both alloy classes can also be synthesized by intense deformation of crystalline multilayer arrays. These developments represent a major level of microstructure control that has an impact on the structural performance and stability.