Fig. 5: Statistical results of the plasticity for twin-structure NC and twin free NC metals.

For d > ∼10 nm, there is a transition from full dislocation intersecting with the TB switch to partial dislocations parallel with TBs, and the critical TT for the deformation transition is grain-size dependent. For d = 6–9 nm, partial dislocation parallel with the TBs dominates. For d < ∼6 nm, there is a transition from dislocation-controlled plasticity switching to GB-mediated plasticity. The black dots and red squares correspond to statistical results of plasticity events in twin-free NC metals.