Nanocrystallization kinetics of Ni-based bulk amorphous alloy

The bulk amorphous alloy Ni45Ti23Zr15Si5Pd12 has been prepared by copper mold casting. The crystallization kinetics of the alloy has been investigated using differential scanning calorimetry by means of continuous heating and isothermal annealing, and the products of crystallization have been analyzed by transmission electron microscopy and X-ray diffraction. The isothermal activation energy obtained from Arrhenius equation increases in the process of crystallization transformation. The details of nucleation and growth during the isothermal crystallization are expatiated in terms of local Avrami exponent and local activation energy. Meanwhile, the origins of nanocrystal formation during the annealing process have also been discussed.