Work toughening effect in Zr41Ti14Cu12.5Ni10Be22.5 bulk metallic glass

作者：Qiu ShengBao; Gong Pan; Yao KeFu^*

来源：Chinese Science Bulletin, 2011, 56(36): 3942-3947.

DOI：10.1007/s11434-011-4782-7

• metallic glass
• mechanical properties
• shear bands

Work hardening is a well-known phenomenon occurring in crystalline metals during deformation, which has been widely used to increase the strength of metals although their ductility is usually reduced simultaneously. Here we report that the plastic strain of Zr41Ti14Cu12.5Ni10Be22.5 (at.%) bulk metallic glasses has been increased from 0.3% for the as-cast sample to 2.5%-8.0% for samples that have experienced pre-deformation under constrained conditions. The pre-deformed glassy alloys possess more free volume and abundant introduced shear bands, which are believed to promote the activation of shear bands in post-deformation and result in an increase in plasticity. The orientation of the pre-introduced shear bands relative to the loading direction will affect the deformation behavior of pre-deformed samples. The present results show that pre-deformation of this glassy alloy will result in work toughening. This work toughening effect can be removed by isothermal annealing at a sub-T (g) (glass transition) temperature, which causes annihilation of free volume and healing of shear bands.

• 出版日期2011-12
• 单位清华大学