Effect of prestraining on the deformation and fracture behavior of Zr44Ti11Cu9.8Ni10.2Be25

Mechanical prehistory is an important factor on the stability of the structure, and consideration of this issue is also useful for determining the mechanisms of post-deformation and fracture processes in bulk metallic glasses. We present investigations to reveal the effect of prestraining on the compressive deformation, morphology of the fracture surface and the evolution of microstructural inhomogeneity in Zr44Ti11Cu9.8Ni10.2Be25 (Vitreloy 1b) “brittle” bulk metallic glass (BMG). The intrinsic plasticity of the BMG increases linearly from 0.7% up to 15% plastic strain upon cold rolling up to 30% prestrain at room temperature due to the change of the short-range order of the glassy phase. Regions of river-like patterns appeared on the fracture surface of prestrained BMGs after compression test, which is similar to that appear during tensile deformation indicating the development of a deformation-induced inhomogeneous residual stress distribution. The effect of uniaxial cyclic compression on the flow stress of the as-cast BMG is also investigated.