Influence of outphase Cu50Ti50 amorphous alloy addition on microstructural evolution of mechanically alloyed Zr66.7Ni33.3 amorphous alloy

The influence of outphase Cu50Ti50 amorphous alloy addition on microstructural evolution of Zr66.7Ni33.3 amorphous alloy has been investigated using a mechanical alloying method. It has been found that the milling induced microstructural evolution is related to the change of peak positions of the first maximum on X-ray diffraction patterns of the as-obtained amorphous alloys. With increasing milling time, the 3 wt.% Cu50Ti50 addition can give rise to the cyclic amorphization transformation of the as-milled alloy. The mechanical stability of the mixing amorphous phase can be greatly enhanced with increasing Cu50Ti50 addition up to 10 wt.%. Moreover, the addition of outphase Cu50Ti50 amorphous alloy not only increases the onset crystallization temperature of Zr66.7Ni33.3 amorphous alloy but also alters its crystallization mode. The effect of outphase amorphous addition on the mechanical stability of the Zr66.7Ni33.3 amorphous phase has been discussed based upon the bond order theory.