Study on the mechanical relaxations of a Zr36Ti24Be40 amorphous alloy by time-temperature superposition principle

Abstract

In order to investigate the mechanical relaxation behavior of the Zr36Ti24Be40 amorphous alloy, the dynamic mechanical properties were measured using dynamic mechanical analyzer (DMA). From the data collected during isothermal multi-frequency dynamic mechanical measurements, the master curves for storage and loss moduli over a broad range of temperature were constructed using the time-temperature superposition (TTS) principle. The temperature dependence of the shift factor was found to follow the Arrhenius relationship and the activation energies, calculated from the Arrhenius relationship, were about 93 and 390 kJ/mol for low temperature mechanical relaxation and viscous flow, respectively. According to the temperature dependence of the shift factor above T-g, no evidence for phase separation was found. The fragility index was also calculated from the relationship between shift factors and temperature and was found to be m approximate to 34, suggesting that the Zr36Ti24Be40 amorphous alloy can be classified into the 'strong' glass.