Fig. 4: Deformation mechanism of the CCIMA at different tensile strains.

a–c GND distribution maps revealing the varied stress concentrations near the grain boundaries with the increase of deformation strains from 5% to 35%, the white line representing grain boundary, while the color bar representing GND density. d–f TEM bright field images taken along the (200) two-beam condition showing the morphologies of deformation substructures of the CCIMA at different strains. g, i High-resolution TEM and corresponding FFT images (insets) revealing the changes in the types of deformation substructures from APB-coupled superlattice dislocations (5%) to intersected SFs (35%). h Atomic-resolution STEM-HAADF image illustrating the existence of SISF at a strain of 15%.