Prominent β-relaxations in yttrium based metallic glasses

Most metallic glasses (MGs) exhibit weak slow beta-relaxation. We report the prominent beta-relaxation in YNiAl metallic glass with a wide composition range. Compared with other MGs, the MGs show a pronounced beta-relaxation peak and high beta-relaxation peak temperature, and the beta-relaxation behavior varies significantly with the changes of the constituent elements, which is attributed to the fluctuations of chemical interactions between the components. We demonstrate the correlation between the beta-relaxation and the activation of flow units for mechanical behaviors of the MG and show that the MG is model system for studying some controversial issues in glasses. (C) 2015 AIP Publishing LLC.