Volume effects in amorphisation by rapid solidification and solid state reaction and in bulk glass-forming alloys

Atomic volume effects in amorphous alloys obtained by rapid solidification and solid-state reaction and in bulk glasses are recalled. a correlation between the ease of glass-formation and the smallness of the volume change on crystallisation Delta(L->)C is confirmed. A method is proposed for estimating the volume of mixing Delta V-mix which is negative for elemental additions to the glass-forming liquid alloy. It is argued that negative Delta V-mix reduces atomic mobility in easy glass-forming alloys thus allowing the suppression during cooling, of nucleation and growth of crystallites. The ZrCuNi system is used as an example for applying this reasoning. It is shown that Al or Ti addition to ZrNiCu alloys lead to a strongly negative Delta V-mix and an expected sharp drop in diffusion-controlled crystal growth kinetics in the melt.