Unveiling correlation between α2 relaxation and yielding behavior in metallic glasses

Relaxation processes usually influence the mechanical properties of glassy materials. Recently, a so-called alpha(2) relaxation has been identified in metallic glasses, caused by the mobility decoupling between different constituting atoms. It locates between the primary (alpha) relaxation and the secondary (beta) relaxation and behaves as an additional alpha relaxation. In this paper, we show that alpha(2) relaxation influences the yielding behaviors of a model Al90Sm10 metallic glass. In particular, the transition from the stress overshoot to nonovershoot yielding and alpha(2) relaxation follow the same time-temperature relation and microscopic origin. Our results suggest that alpha(2) relaxation provides an additional way to control the mechanical properties of metallic glasses.

Automated summary

The alpha(2) relaxation identified in metallic glasses influences the yielding behaviors of the materials, providing an additional way to control their mechanical properties. The transition from stress overshoot to nonovershoot yielding is related to the same time-temperature relation and microscopic origin of the alpha(2) relaxation.