The effect of Fe on the crystallization behavior of Al-Mm-Ni-Fe amorphous alloys

The crystallization behavior and thermal stability of Al(86)Mm(4)Ni(10-x)Fe(x) alloys were investigated as a function of Fe content. Alloys, produced by a single roll melt-spinner at a circumferential speed of 52 m/s, revealed fully amorphous structures. The thermal stability of the present amorphous alloys increased with the increase of Fe content. The activation energy for crystallization of alpha -Al increased as the Fe content increased. This increase of activation energy resulted in the simultaneous precipitation of alpha -Al and intermetallic phase observed especially in Al(86)Mm(4)Ni(5)Fe(5) and Al(86)Mm(4)Ni(2)Fe(8) alloys. The glass transition was observed in DSC thermogram only after proper annealing treatment. The effect of alloy composition on the thermal stability could be explained in terms of the atomic structure of the amorphous alloy. (C) 2001 Kluwer Academic Publishers.X1116sciescopu