Diffusion in metallic glasses and supercooled melts

Abstract

A wide variety of materials ranging from oxide glasses to polymers can solidify as glasses rather than crystals. While diffusion plays an important role in all media at elevated temperatures, diffusion in glasses is of particular interest. The metastability of these materials makes them prone to various rearrangement processes such as structural relaxation, phase separation and crystallization. In the supercooled liquid state diffusion is very important in connection with the glass transition, which appears to be a kinetic phenomenon [1]. With the recent discovery of novel bulk-glass-forming alloys, exhibiting high stability against crystallization in the supercooled state [2,3], the dynamics of the glass transition could also be studied in metallic systems, which are the paradigm of dense random packing. Stimulated by the development of bulk metallic glasses and advances in computer simulation, recent progress in the understanding of the diffusion mechanisms in metallic glasses and supercooled melts has been considerable. For recent reviews the reader is referred to [4, 5].