A Fictive Stress Model Calculation of Stress-Overshoot: A Nonlinear Viscoelastic Behavior in Metallic Glass

Abstract

A model, based on the hypothesis of stress-induced structural relaxation and a concept of fictive stress, is proposed for nonlinear viscoelastic behavior in glassy materials. A model calculation has been carried out on the stress-overshoot phenomenon observed in metallic glasses. The model calculation reproduces the experimental results of a Pd₄₀Ni₁₀Cu₃₀P₂₀ glass fairly well, in particular, the development of stress-overshoot behavior with increasing strain rate and lowered temperature. In addition, the model reveals a stress-overshoot and -undershoot oscillatory behavior which has not been reported previously in metallic glasses, but has been observed in many polymer solutions.