| Abstract Scope |
Different glasses exhibit markedly different stability around their glass transition temperature (Tg). Metallic glasses (MGs) are conventionally regarded as more metastable compared to other glasses such as silicate glass or amber [1]. Due to its low Tg, the Ce-based MG shows a significant aging effect at room temperature, equivalent to high-temperature annealing at 0.85Tg [2]. This allows for infinite aging experiments at an appropriate temperature window, which is impossible for other high-Tg amorphous alloys. Our 17.7-year aging experiment on a Ce-based MG around its Tg revealed that it could transform into a kinetically and thermodynamically hyperstable state with strong resistance to crystallization, similar to million-year-aged amber [3]. This ultrastability is attributed to the strong fragility of the Ce-based MG, which accelerates its relaxation toward a lower energy state and effectively inhibits nucleation and crystallization, maintaining high stability.
References
[1] Z. Q. Chen, Y. Zhao, B. Zhang et. al., Sci. Adv. 9 (2023) eadi6086.
[2] B. Zhang, W. H. Wang et. al., Phys. Rev. Lett. 94 (2005) 205502.
[3] Y. Zhao, B. Zhang et. al., Sci. Adv. 8 (2022) eabn3623. |