| In-situ tensile tests performed in a scanning electron microscope (SEM) were used to study mechanical behavior of a Zr-Bulk metallic glass and highlight the effect of strain rate. Shear band generation and propagation was observed at several stages of deformation. Fracture surface was analyzed immediately after rupture under SEM secondary vacuum, avoiding contamination of sample surface. We found that contrary to experimental results performed in constrained geometries such as in compression or indentation, increasing strain rate in tension leads to formation of multiple parallel shear bands and enhanced macroscopic plasticity up to 1.5% with slight decrease of elastic strength and Young modulus. Fracture surface analysis revealed that flow is an accommodation mechanism for deformation in metallic glasses. |
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