Atomic-scale snapshots showing deformation details relating to the three strain excursions shown in Figure 4. Here, fcc atoms are not shown for clarity. (a) Partial dislocations are nucleated at the void surface. (b) Dislocation motion is hindered by the TBs, leaving TB steps on the twin planes and intrinsic stacking fault ribbons. (c) Subsequent partial dislocations are nucleated from the same location at the void surface but on adjacent atomic planes. (d) TB blocking dislocation motion, leaving TB steps and extrinsic stacking faults, (e) Subsequent dislocation emission on adjacent atomic planes. (f) The formation of twin nuclei due to TB blocking. The blue arrows indicate the nucleation of dislocations from TB steps.