The most pronounced β-relaxation was found in the Y-based binary metallic glasses (MGs). The correlation between β-relaxation and local atomic structure was studied. The dynamic mechanical measurements were performed for three chosen binary systems:Zr-, Ti-, and Y-based MGs. The experimental results show that, in each system,the larger negative enthalpy of mixing (ΔH_m) between the component elements makes β-relaxation become more pronounced. The less negative value of ΔH_m facilitates the formation of icosahedral clusters, which have a pinning effect on the excitation of β-relaxations and correspondingly make the β-relaxation become less pronounced. These chemical effects on β-relaxations can only be compared in the same MG system, and it is not suitable for the comparison between different systems due to the different features of the major metallic elements.

We report the formation of LaGa-based bulk metallic glasses. Ternary La-Ga-Cu glassy rods of 2-3 mm in diameter can be easily formed in a wide composition range by the conventional copper mold casting method. With minor addition of extra elements such as Co, Ni, Fe, Nb, Y, and Zr, the critical diameter of the full glassy rods of the La-Ga-Cu matrix can be markedly enhanced to at least 5 mm. The characteristics and properties of these new LaGa-based bulk metallic glasses with excellent glass formation ability and low glass transition temperature are model systems for fundamental issues investigation and could have some potential applications in micromachining field.