Experimental study on the effect of normal stress on the shear banding in a Zr-based bulk metallic glasses

A special fixture, which can control the ratio(lambda) of normal stress/shear stress, was used to study the effect of normal stress on the shear banding behaviors in a Zr-based bulk metallic glasses in the present paper. The experimental results demonstrated that the plastic displacement increased with increasing of lambda. Observations of shear bands pattern on the sample surfaces indicated that normal stress have significant impact on the inclined angle, numerical density and length of shear bands. In addition, normal stress is the major factor of inducing multiple shear bands with intersecting, branching and slipping. Based on the observations, the mechanism of plasticity enhancement due to the increasing of normal stress was explored.