Relaxation behavior on high frequency profile in strong/fragile metallic glass-forming systems

The coupling of the slow β-relaxation and the prominent α relaxations in various metallic glass-forming systems with different fragilities is studied. The coupling of the α- and slow β-relaxation depends on the fragility of the metallic liquids and causes an obvious violation of the time–temperature superposition principle in rather strong metallic glass-forming liquids. The results are qualitatively discussed based on the microstructural characteristic of the BMGs consisting of the dense-packing regions and loose-packing regions.