Preparation and thermal stability of mechanically alloyed Ni–Zr–Ti–Y amorphous powders

In the current study, amorphous Ni67−xZr10Ti23Yx alloy powders were synthesized by mechanical alloying technique. The mechanically alloyed powders were amorphous, after 5 h of milling, at compositions of Ni67−xZr10Ti23Yx (x=0–12). The amorphization behavior of Ni59Zr10Ti23Y8 was examined in details. The conventional X-ray diffraction and synchrotron EXAFS results confirm that the fully amorphous powders formed after 5 h of milling. ermal stability of the Ni67−xZr10Ti23Yx amorphous powders was investigated by differential scanning calorimeter. As the results demonstrated, the amorphous powders with low yttrium concentration (x=0–6) or high yttrium concentration (x=12) exhibit no glass transition behavior. However, the Ni67−xZr10Ti23Yx (x=7–10) amorphous powders were found to exhibit a wide supercooled liquid region before crystallization.