Oxygen impurity sequestering in amorphous Zr-Al-Ni-Cui alloys by scandium addition

An XRD study of a series of Zr52.5Cu17.9Ni14.6Al10Ti5 alloys, with and without small additions of further alloying elements, has shown that: (a) the development of the crystalline phase along the wedge varies between replicate samples, but did not follow smooth curves thus indicating variations in the local nucleation (composition) rate; (b) small additions of scandium comparable with the oxygen content of some 100 ppm by weight showed an increase in retention of the amorphous phase by some 50% where it is thought that the scandium sequesters the oxygen by forming Sc2O3; (c) the volume change of the amorphous to crystalline transition is estimated to be about 0.5% at ambient temperature.