Non-isothermal strain recovery as a result of irreversible structural relaxation of metallic glasses

A quantitative model is proposed for the non-isothermal strain recovery induced by stress pre-annealing of metallic glasses. It is assumed that the nonisothermal strain recovery is determined by irreversible atomic rearrangements occurring in directional internal stress fields created by unloading of samples preannealed under stress. Special experiments are performed to make a thorough test of the model. It is shown that the model correctly reproduces the temperature position and height of the recovery strain rate peak observed in the experiment. It is concluded that the macroscopically reversible mechanical behaviour (strain recovery) can be determined by irreversible structural relaxation of a metallic glass.