Formation of adiabatic shear band in metal matrix composites

Strain gradient drives shear banding in metallic glasses

“…3(e) shows, the strain gradient effect is magnified step by step and the samples with the largest degree of L5FS show the most pronounced strain gradient effect. All of this information reminds us that the inherent strain gradient due to structural heterogeneity could be a candidate for the driving force for the initiation of shear banding, as has been shown in particle-reinforced metal matrix composites [46,52,61].…”

“…The strain gradient is such a physical quantity characterizing the limited nonlocality and it has already taken the spatial distribution of the strain field into consideration. The influences of strain gradient on strengthening, work hardening, and shear instability were broadly reported before [46,[50][51][52][53][54][55][56]. The strain gradient is highly anticipated to provide the long time missing bridge linking the activation of isolated STZs to the emergence of shear bands.…”

“…Figure 1(a) shows that the high L5FS regions are embedded into the matrix with medium and low degrees of L5FS. Inspired by particle-reinforced metal matrix composites [46], we may reasonably hypothesize that there exist hard "particles" which represent the most stable clusters showing a high structural and energetic stability, as schematically shown in Fig. 1(b).…”

An enhanced continuum model for size-dependent strengthening and failure of particle-reinforced composites

“…Clustering of GNDs will also influence the immediate neighborhood and mediate failure processes. For example, Dai et al [12] showed experimentally and analytically that the additional strengthening due to GNDs may accentuate adiabatic shear localization at high loading rates. Rate-dependent failure response varying from catastrophic shear cracking at quasi-static strain rates ($10 À3 s À1 ) to gradual softening due to microcracking and shear softening at high strain rates (>10 3 s À1 ) is also observed in nano-micro ("trimodal") particulate composites [8].…”

Suppression of repeated adiabatic shear banding by dynamic large strain extrusion machining

“…According to the dealing method introduced in Bai (1982), Clifton et al (1984), Dai and Bai (2008), Dai et al (2004), Jiang and Dai (2009), Molinari (1997), Molinari et al (2002), the stability analysis is simplified by seeking an inhomogeneous deformation solution with respect to small perturbations on the homogeneous solution. Such that…”