In this study, the kinetic of Au-based BMG (Au50Cu25.5Ag7.5Si17 (at%)) at high temperature in supercooled liquid region was investigated Crystallization kinetics of this amorphous alloy under non-isothermal (continuous heating) and isothermal conditions were investigated by differential scanning calorimetry (DSC). The results show that crystallization in this bulk metallic glass has one stage crystalline precipitation process during continuous heating. It was found that glass transition and crystallization kinetics are the function of continuous heating rate. Under non-isothermal conditions, activation energies corresponding to the characteristic temperatures were estimated by Kissinger equation. The calculated activation energies of glass transition, onset of crystallization and crystallization peak temperature are 246,183 and 161 kJ/mol respectively. These activation energies revealed that the energy barrier for the glass transformation is higher than that for crystallization. The crystallization mechanism under isothermal condition was investigated by using Johnson – Mehl – Avrami (JMA) equation. The Avrami exponent is mainly in the range of 1 to 1.6, which indicates heterogeneous nucleation with significant volume at the beginning of the transformation.
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