Anomalous change in nanocrystallization of amorphous Zr-Cu-Ni alloy

摘要: Employing X-ray diffraction (XRD), differential scanning calorimetry (DSC) and transmission electron microscopy (TEM), an anomalous change in the nanocrystallization of metallic Zr70Cu20Ni10 glass under two different conditions, i.e., continuous heating isothermal annealing, has been observed. Both TEM observations XRD results confirm that first exothermic reaction DSC traces mainly corresponds to precipitation Zr2Cu phase, while second one Zr2Ni nanoparticles. In contrast this, when annealed supercooled liquid region preferential phase nanocrystals instead phase. The origin such can be explained by Kirkendall effect between Cu Ni atoms for former difference heat mixing Zr-Ni Zr-Cu atomic pairs. Crystallization amorphous alloys extensively studied because practical theoretical interest crystal nucleation growth a high undercooling regime [1]. Two methods are often utilized investigate crystallization process alloys, i.e. annealing processes. For process, we obtain apparent activation energy alloy means