Universality of slip avalanches in a ductile Fe-based bulk metallic glass

Intermittent serrated flows of a novel ductile Fe₆₀ Ni₂₀ P₁₃ C₇ bulk metallic glass (BMG) at variant strain rates were investigated by statistics analysis. Peak and clutter distribution of slip-avalanche magnitudes are displayed during stable plastic flows at strain rates of 2×10⁻⁴ s⁻¹ and 5×10⁻⁵ s⁻¹, respectively, which means that serration behavior depends on the strain rate. However, the remarkable agreement between measured slip-avalanche magnitudes and the scaling behavior, i. e. a universal complementary cumulative distribution function (CCDF) predicted by mean-field theory (MFT) model, indicates that the plasticity of the present Fe-based BMGs can be tuned by imposed strain rates: S_max∼ɛ˙^-λ. This tuned plasticity is elucidated with expended free-volume model. Moreover, the scaling behavior of serrated flows for other strain rates can be predicted as well.