Correlations between shear bands and plasticity in Ti-based bulk metallic glass

The compressive plasticity of Ti₄₀Zr₂₅ Ni₈Cu₉Be₁₈ bulk metallic glass with different specimen aspect ratio was investigated. The specimens with aspect ratios A>1 exhibit a poor plasticity, contrariwise, showing an excellent plasticity. The maximum elongation before failure is up to about 86%. The difference in the plasticity is a result of shear bands behavior due to the geometrical constraints. The results show a linear increase in the density (spacing) of shear bands with increasing of stress, and the hardness decreases linearly with increasing of plastic strain. The results are consistent with a strain-induced local dilatation, and the free volume in the glass increases after deformation relative to the undeformed glass.