The delayed aging achieved through stress-controlled cyclic loading in metallic glasses^✰

Aging, an intrinsic characteristic of metallic glasses (MGs), poses a fundamental challenge to their long-term structural stability and functional reliability. To enhance stability and extend the service life of MGs, it is essential to suppress the evolution of their energy state over time. In this study, we propose a stress-controlled cyclic loading protocol in molecular dynamics simulation that effectively achieves a delayed aging process in Zr₅₀Cu₄₀Al₁₀ MG. The results demonstrate that, regardless of the stress magnitudes investigated in this study, cyclic loading consistently leads to the retardation of aging, although aging relative to the initial configuration still proceeds. This retardation effect enables tunable control over the energy state, atomic structure, and macroscopic properties of MGs. That aging continues is corroborated by the reduction in the formation of large flow unit clusters and the decreased dynamic heterogeneity. Furthermore, this retardation effect becomes more pronounced with increasing stress amplitude. This is evidenced by the enhanced formation of flow unit clusters under higher stress amplitudes compared to lower ones after the same number of cycles. Structurally, the averaged local five-fold symmetry is an important indicator of improved structural stability. This work not only demonstrates an effective strategy for delaying aging in MGs but also elucidates the underlying mechanisms from both dynamical and structural perspectives, offering valuable insights for designing metastable MG systems with enhanced stability for advanced applications.