The correlation between β relaxation and shear transformation zone in LaNiAl bulk metallic glasses: The effect of cryogenic thermal cycling treatment

Despite the general acceptance that β relaxation and shear transformation zone (STZ) may share similar microstructure origin and possess identical activation energies, i.e., E_β = W_STZ, in this study, we experimentally demonstrate opposite changing trends of the two energies could be derived in La₆₀Ni₂₅Al₁₅ metallic glass before and after cryogenic thermal cycling treatment with distinct temperature intervals. Specifically, the experimental results indicate larger STZ requires higher W_STZ, while lower E_β is needed to activate the atoms involved in string-like motions that corresponding to easier β relaxation. The results of this article will deepen our understanding of the correlation between relaxation and deformation carriers of the La-based metallic glasses.