Fig. 10

Distribution of subsurface dislocations in unloading process of nano-indentation (color online). The corresponding indentation depths of a–f are 4 nm, 3 nm, 2 nm, 1 nm, 0 nm, and − 1 nm, respectively. Color scheme: deep blue for perfect dislocations, green for Shockley dislocations, pink for Stair-rod dislocations, yellow for Hirth dislocations, light blue for Frank dislocations, and red for unidentified dislocations