Abstract
Non-isothermal crystallization transformation kinetics and isothermal crystallization kinetics in super-cooled liquid region (SLR) in Zr 55Cu 30Ni 5Al 10 bulk metallic glasses were studied by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). In isochronal mode, the average values of activation energy in Zr 55Cu 30Ni 5Al 10 bulk metallic glass determined by different models (Kissinger method, Flynn-Wall-Ozawa method and Augis-Bennett method) are in good agreement with each other. In addition, the isothermal transformation kinetics in Zr 55Cu 30Ni 5Al 10 bulk metallic glasses was described by the Johnson-Mehl-Avrami (JMA) model. For Zr 55Cu 30Ni 5Al 10 bulk metallic glass, the Avrami exponent n ranges from 2.2 to 2.9, indicating that crystallization mechanism in the bulk metallic glass was mainly diffusion-controlled; crystal growth is controlled by long range ordering diffusion in three-dimensional growth during isothermal crystallization process. The average value of activation energy in Zr 55Cu 30Ni 5Al 10 bulk metallic glass is 469 kJ/mol in isothermal transformation process.
Original language | English |
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Pages (from-to) | 577-584 |
Number of pages | 8 |
Journal | Transactions of Nonferrous Metals Society of China (English Edition) |
Volume | 22 |
Issue number | 3 |
DOIs | |
State | Published - Mar 2012 |
Externally published | Yes |
Keywords
- Avrami exponent
- Zr Cu Ni Al
- crystallization kinetics
- metallic glass
- thermal analysis