Composition dependence of metallic glass plasticity and its prediction from anelastic relaxation – A shear transformation zone analysis

A hierarchically correlated flow defect model for metallic glass: Universal understanding of stress relaxation and creep

“…In fact, the evolution of anelastic strain can be studied by the small-deformation experiments at low temperature. Since the values of deformation was very small, almost comparable to those of elastic deformation, SMDs accommodating anelastic deformation are isolated and did not interact with each other (Atzmon and Ju, 2014;Ju et al, 2011;Lei et al, 2020). As shown by the comparison with experimental results in Fig.…”

“…"shoulder" or "excess wing" on the low temperature side of the α relaxation spectra can be observed. Recent investigations demonstrated that the β relaxation is of importance for understanding some key issues in metallic glasses, such as diffusion (Ngai et al, 2017), physical aging (Yu et al, 2014) and deformation mechanisms (Lei et al, 2020;Wang et al, 2017;Zhang et al, 2019) The solid lines in Fig. 5 show the evolution curves of 𝐸𝐸′ and 𝐸𝐸′′ with temperature calculated by Eq.…”

“…When stress is applied, the deformation unit first being activated is selected from many potential sites in a metallic glass. It is easy to envision that the defect sites with high free energy and large atomic mobility are easier to be activated to produce atomic rearrangement (Johnson and Samwer, 2005;Lei et al, 2020;Wang and Wang, 2019). As described in the literature (Argon and Shi, 1983;Atzmon and Ju, 2014;Qiao et al, 2019b), these deformation units are isolated spatially at low strain, and the deformation carried by them is reversible and recoverable (anelastic deformation) after removal of stress.…”

Analysis of the anelastic deformation of high-entropy Pd20Pt20Cu20Ni20P20 metallic glass under stress relaxation and recovery

“…Anelastic behavior during recovery process is an effective method to investigate the distribution and evolution of flow defects related to free-volume zones in HE-MGs [39,61]. The anelasticity originates from the microscopic heterogeneous behavior of MGs [63].…”

“…The long-term mechanical evolution of MGs has been intensely investigated by creep [36,37], stress relaxation [38][39][40], and recovery experiments [41]. In particular, stress relaxation is performed at a constant strain by the application of uniaxial tension or compression on the specimen, and monitoring how the stress gradually decrease with relaxation time [38].…”