fig7

Figure 7. The energy distribution of atoms near the crack tips, as denoted by system energy evolution curve during emission of different dislocations at the crack tips in FCC Al. (A) Emission of the first partial dislocation dominated by the crack-tip nucleation mechanism; (B and C) Emission of the second and third partial dislocations dominated by the back twinning nucleation mechanism; (D) Emission of the fourth partial dislocation dominated by the forward twinning nucleation mechanism. FCC: Faced-centered cubic.