Characteristic length scales governing plasticity/brittleness of bulk metallic glasses at ambient temperature

Yang, Y.; Ye, J. C.; Lu, J.; Liaw, P. K.; Liu, C. T.
January 2010
Applied Physics Letters;1/4/2010, Vol. 96 Issue 1, p011905
Academic Journal
In this letter, we propose a unified theory for the size-dependent plasticity of bulk metallic glasses (BMGs) at room temperature. Based on the principle of energy balance and the shear-banding kinetics, two characteristic length scales are derived. One is a sample-geometry dependent variable related to the elastic energy released to drive shear-band propagation and the other is a material-dependent constant related to the internal resistance to brittle fracture. It is shown that this unified theory is effective in explaining many unusual deformation and fracture behaviors of BMGs.


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