Fragility of superheated melts and glass-forming ability in Al-based alloys

A new concept, the fragility of superheated melt defined as M=|∂η(T)/η(TL)∂T/TL|T=TL|=|∂ηr∂Tr|Tr=1|, has been proposed in this work. It has been found that this kind of fragility value of liquid above liquidus temperature is closely related to the glass-forming ability in Al-based amorphous alloys. By calculation of the M, the glass-forming ability of Al-based amorphous alloys could be predicted prior to the preparation for amorphous solids.