A comparative study on characteristic relaxation in Ce65Al10Cu20Co5 and Zr46.75Ti8.25Cu7.5Ni10Be27.5 bulk metallic glasses and supercooled liquids

The relaxation behaviors of Ce65Al10Cu20Co5 and Zr46.75Ti8.25Cu7.5Ni10Be27.5 (Vit4) bulk glass-forming supercooled liquids were investigated by frequency-dependent heat capacity measurements on a temperature-modulated differential scanning calorimetry (TMDSC) apparatus. The relaxation behaviors of the investigated samples were well described by Kohlrausch–Williams–Watts (KWW) function. The temperature dependences of characteristic relaxation time of the glass-forming liquids were fitted by Vogel–Fulcher–Tamman (VFT) equation. The derived fragility index m shows that Ce65Al10Cu20Co5 (m = 31) liquid is a stronger liquid than Vit4 (m = 42). The sizes of cooperatively rearranging region (CRR) for Ce65Al10Cu20Co5 and Vit4 liquids were estimated to be 1.6 and 1.4 nm, respectively.