Effect of temperature on the degradation of mechanical properties in ZrNb metallic glass

This study investigates the cyclic loading behavior of Zr₅₀Nb₅₀ metallic glass (MG) across a temperature range from 100 K to 500 K using molecular dynamics simulations. The results demonstrate that cyclic loading leads to a degradation in the MG’s mechanical performance, evidenced by decreases in Young’s modulus ($E$) and maximum stress (${\sigma }_m$), alongside an increase in residual strain (${\varepsilon }_r$) and non-monotonic increase in yield strain (${\varepsilon }_y$). The degradation trends in $E$ and ${\sigma }_m$ were more pronounced at lower temperatures, suggesting that enhanced atomic mobility at higher temperatures helps mitigate the extent of damage. The accumulation of shear transformation zones throughout the cycles plays a crucial role in the fatigue behavior. Atomic-scale analyses, including radial distribution functions and Z cluster populations, revealed subtle changes in medium-range order and weakening of the MG backbone at higher temperatures, which corresponded with the observed mechanical performance. These findings provide important insights into the interplay between temperature, atomic structure, and mechanical performance in metallic glasses.