Kinetics And Phase Formation During Crystallization Of Hf64cu18ni18 Amorphous Alloy

In this work, crystallization kinetics and phase formation of the Hf64Cu18Ni18 glassy ribbon were studied. It was observed that the ribbon crystallizes via two exothermic peaks. Further, the activation energy (E (a)) corresponding to each peak was calculated by Kissinger and Augis-Bennett methods. These methods showed nearly similar values of E (a). The crystallization product of ribbon was identified by X-ray diffraction and discussed in view of prediction using the CALculation of PHAse Diagram (CALPHAD) approach. The identified phases indicate that the HfNi and Hf2Cu, Hf2Ni are formed after the first and second exothermic crystallization peaks, respectively. Further, the Avrami exponent (n) was calculated as 1.2 and 1.4 for the first and second crystallization peaks, respectively. Avrami exponent values show that crystallization takes place at non-random nucleation sites with either one or two-dimensional growth.