| Autor: |
Wu, Xuebang, Shui, Jiapeng, Wang, Zhi-Zhi, Zu, Fang-Qiu |
| Předmět: |
|
| Zdroj: |
Journal of Applied Physics; Oct2012, Vol. 112 Issue 8, p083530, 6p, 7 Graphs |
| Abstrakt: |
The nature of internal friction peak associated with the first-order phase transformation remains an unsolved fundamental problem in many fields of science and technology. Here, the internal friction behaviors of crystallization process of Zr55Al10Ni5Cu30 bulk metallic glass were investigated. With increasing temperature, the internal friction spectra exhibit a peak, which shows a crossover from a relaxation behavior to a phase transformation behavior. The combined differential scanning calorimetry results show that the phase transformation behavior at higher temperature is related to the crystallization process of amorphous alloy, while the relaxation behavior at lower temperature is composed of two processes: One originates from the glass transition and the other from the relaxation due to the structural instability before phase transformation. According to the coupling model and the compensation effect, the primitive activation energies for the glass transition and the structural instability before crystallization are about 1.0 eV and 1.4 eV, respectively. Therefore, it is suggested that the mechanism of internal friction peak associated with the first-order phase transformation is due to the structural instability before phase transformation and the sudden change of the relaxation parameters when phase transformation happens. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
