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The most pronounced β-relaxation was found in the Y-based binary metallic glasses(MGs). The correlation betweenβ-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(?Hm) between the component elements makes β-relaxation become more pronounced. The less negative value of ?Hm 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.
The most pronounced β-relaxation was found in the Y-based binary metallic glasses (MGs). The correlation between β-relaxation and local atomic structures 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 (? Hm) between the component elements makes β-relaxation became more pronounced. The less negative value of? Hm 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.