Influence of a supercooled liquid on crystallization behaviour of Al-Y-Ni-Co metallic glass

The present paper aims to report an effect of a supercooled liquid region on crystallization behaviour of an Al₈₅Y₈Ni₅Co₂ metallic glass produced by rapid solidification of the melt. It is found that crystallization behaviour of the above-mentioned Al-based metallic glass, above glass-transition temperature and below it, follows different transformation mechanisms. Formation of the primary nanoscale α-Al particles observed during continuous heating, or after annealing above glass-transition temperature, does not occur by the crystallization reaction during isothermal annealing below glass-transition temperature. At such conditions, an unknown metastable phase is formed conjointly with α-Al by the eutectic-like mechanism.