By isolating the process of dislocation emission from a crack tip under an applied tensile stress, we extract from a molecular dynamics simulation the atomic-level displacement and stress fields on the activated slip plane before and after the nucleation event. The stress-displacement relations so obtained provide a direct link with recent continuum descriptions of brittle versus ductile behavior in crack propagation. Crack-tip shielding by the emitted dislocations is demonstrated, as is the role of surface steps in dislocation nucleation and crack-tip blunting. © 1997 The American Physical Society.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
Cleri, F., Yip, S., Wolf, D., & Phillpot, S. R. (1997). Atomic-scale mechanism of crack-tip plasticity: Dislocation nucleation and crack-tip shielding. Physical Review Letters, 79(7), 1309 - 1312. https://doi.org/10.1103/PhysRevLett.79.1309