Effect of physical aging and cyclic loading on power-law creep of high-entropy metallic glass

The power-law relationship between creep rate decay and time is one of the intrinsic characteristics of metallic glasses. In the current work, a La₃₀Ce₃₀Ni₁₀Al₂₀Co₁₀ high-entropy metallic glass was selected as the model alloy to test the influences of physical aging and cyclic loading on the power-law creep mechanism, which was probed by the dynamic mechanical analysis in terms of the stochastic activation, and contiguous interplay and permeation of shear transformation zones. It is demonstrated that a notable discrepancy appears between thermal treatment and mechanical treatment on the power-law creep mechanism of this high-entropy metallic glass. On the one hand, physical aging below the glass transition temperature introduces the annihilation of potential shear transformation zones which contribute to creep. On the other hand, cyclic loading can tailor the “forward” jump operations competing with the “backward” ones of shear transformation zones by controlling the interval time (recovery time). The current research offers a new pathway towards understanding the creep mechanism of high-entropy metallic glasses.