A hysteretic loop phenomenon at strain amplitude dependent damping curves of pre-strained pure Mg during cyclic vibration

In this study, twins were introduced into pure Mg by pre-deformation, the strain amplitude dependent damping in pre-strained pure magnesium was investigated using cyclic vibration. The strain amplitude dependent damping curve exhibited a hysteretic loop as the strain amplitude was cycled. The damping value was greater during the high strain amplitude regime when the strain amplitude increased than when strain amplitude decreased. For the low strain amplitude regime, the opposite trend was observed. The results point to the damping behavior transitions between the two regimes occurring at a specific strain amplitude, increasing commensurately with increased pre-strain. This hysteretic loop phenomenon is attributed to the difference in mechanical energy consumed by the motion of the twin boundaries during cyclic vibration. The hysteretic loop indicates that twin dampening already exists. Therefore, the strain amplitude value of the intersection may be used as a reference parameter to detect twin damping. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

Twins were introduced into pure Mg for pre-deformation in this study, and the strain amplitude dependent damping behavior was investigated. A hysteresis loop was observed in the damping curve as the strain amplitude cycled. The results indicate a transition in damping behavior at a specific strain amplitude, with increased pre-strain leading to increased damping.