Dynamic fragmentation induced by network-like shear bands in a Zr-based bulk metallic glass

Different deformation behaviors of two in-situ Ti-based metallic glass matrix composites upon quasi-static and dynamic compressions

“…7. It can be seen that the Ti6Al4V alloy [31] exhibits positive strain-rate sensitivity while the Zr 41.2 Ti 13.8 Cu 10 Ni 12.5 Be 22.5 (Vit 1) metallic glass [32] shows the negative one. When in-situ MGMCs are subjected to external loadings upon different strain rates, the strain-rate sensitivity is determined by the competition between the positive effect of the crystalline dendrites and the negative effect of the glass matrix.…”

Effect of strain rates on deformation behaviors of an in situ Ti-based metallic glass matrix composite

“…Actually, more thermal softening from larger temperature rising further leads to the lower critical shear stress [34], indicating a negative SRS. Figure 5 summarizes the variation of the yielding strength with the strain rate in monolithic BMGs [35][36][37][38], in situ and ex situ MGMCs [13,16,18,39,40], and crystalline alloys [41,42]. For comparison, the yielding stress has been normalized to the yielding stress for each alloy under quasi-static compression.…”

“…It can be clearly seen that the BMGs exhibit negative SRS over a wide range of strain rates. Indeed, the yielding strength decreases with increasing strain rates upon dynamic loading, which has been attributed to the dominant thermal softening during dynamic compression [35]. However, for most in situ and ex situ MGMCs by introducing crystalline phases, a positive SRS prevails owing to the dislocation multiplication within the reinforced phases under high strain rates [32,40].…”

A comparative study of the rate effect on deformation mode in ductile and brittle bulk metallic glasses

“…Thus, the various deformation modes in BMGs are determined by different shear banding behaviors. Extensive reports have shown that the shear banding behaviors and hereby deformation modes are influenced by various factors, including material compositions [14][15][16], loading rate [17][18][19][20][21][22][23][24] and temperature [25][26][27][28]. In addition, sample size [29][30][31] and stress state during loading [32,33] also affect deformation mode.…”

“…Among these factors, loading rate is considered as one of the most significant since metallic glasses are applied to areas over a wide range of strain rate. Zeng et al [23] reported a shear-dominated failure under quasi-static compression, while a fragmental fracture under dynamic compression. The flow serrations during plastic flow was suggested to be related to shear stability [34], and the serrations gradually disappeared with increasing strain rate [35,36].…”