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Binary Zn-TM (TM = Zr, Nb, Mo) alloys have been prepared by mechanical alloying from elemental powders in a planetary ball mill. The structure and thermal behaviour were investigated by X-ray diffraction and differential thermal analysis. Completely amorphous powders were obtained in the Zn-Zr and Zn-Nb systems, whereas for the Zn-Mo system mechanical alloying results in a crystalline Mo-based solid solution. Furthermore the factors related to the possibility and rate of amorphization were discussed.

An amorphous Zn60Zr40 alloy was synthesized for the first time by mechanical alloying of pure elemental powders of Zn and Zr using a planetary high-energy ball mill. The structure and thermal behaviour were analysed by X-ray diffraction and differential thermal analysis. The result indicates that the large negative enthalpy of formation of Zn-Zr provides the necessary driving force for solid-state amorphization. In addition, the realization of the amorphization of Zn-Zr shows that Zn is a fast-moving species in host Zr although the ratio of Vimp(Zn)/V(Zr) is larger than the critical value of the Zr-TM (3d) system, 0.58. The activation energy of crystallization of the glass is about 3.068 eV.

The amorphous Cu60Ti40-xZrx (x=0, 10, 20, and 30) alloys were successfully synthesized by mechanical alloying of pure elemental powders of Cu, Ti and Zr using a planetary high-energy ball mill. The structure and thermal behaviour of these alloys were analysed by X-ray diffraction and differential scanning calorimetry. The results indicate that the replacement of Ti by Zr increases the chemical driving force of the amorphization reaction and the interaction of dissimilar atoms of the Cu-Ti-Zr ternary system. Thus, the glass-forming tendency, the amorphization rate and the stability are all improved. In addition, the stability of Cu-Ti-Zr amorphous powders is related to the crystallization sequence and the first crystallization phase.