Figure 3: High-resolution TEM of SFTs and their interaction mechanism with twin boundaries.
From: Removal of stacking-fault tetrahedra by twin boundaries in nanotwinned metals
(a) HRTEM image of two truncated SFTs during their interactions with CTBs. SFT-a was truncated from its apex, whereas SFT-b was destructed from its base. Scale bar, 4 nm. (b) Schematics of two types of interactions between SFTs and twin boundaries corresponding to the two cases in (a). The removal of SFT initiated from its apex (in contact with a twin boundary) results in the formation of dislocation loops on {111} plane in the twin lattices. In the lower case, the interaction of a mobile partial with stair-rod dislocations, AB and AC, results in two new mobile partials that can migrate on the surface of SFT and lead to its decomposition. (c) Stacking faults along twin boundaries in irradiated nt Ag (tave=8 nm) were induced by SFT–twin boundary interactions as shown by XTEM micrograph. Scale bar, 40 nm. (d) HRTEM micrograph showing the formation of groups of stacking faults in irradiated thin nt Ag (up to 1 dpa). Scale bar, 4 nm.
