Abstract

This study investigates the degradation of mechanical properties in CuZr metallic glasses (MGs) under cyclic loading using molecular dynamics simulations. Both as-cast (AC) and cryogenically thermal-cycled (TC) samples with Cu36Zr64 and Cu64Zr36 compositions were analyzed. Results show that cyclic loading significantly degrades Young's modulus, ultimate tensile stress, and toughness, with most pronounced reductions occurring in the initial cycles. TC samples exhibit improved ductility and stability compared to AC samples. In contrast, AC samples demonstrate greater initial strength but faster degradation. Cu-rich samples maintain higher strength but degrade similarly to Cu-poor samples. The AC Cu-rich sample experiences more localized deformation and delayed degradation, while TC and AC Cu-poor samples quickly reach a steady state. These findings highlight the influence of atomic composition and thermal treatments on the mechanical performance and degradation behavior of MGs.