Influence of Grain Boundary Structure on Dislocation Nucleation in FCC Metals
Tschopp, M. A., Spearot, D. E., & McDowell, D. L. (2008). Influence of Grain Boundary Structure on Dislocation Nucleation in FCC Metals. In J. P. Hirth (Ed.), Dislocations in Solids. 14, 43-139.
This work focuses on modeling the atomic level mechanisms associated with the structure and inelastic behavior of homophase high-angle boundaries on the nanoscale. We compute boundary structure and energy for both symmetric and asymmetric tilt boundaries for pure FCC copper and aluminum. Discrete atomic scale mechanisms associated with dislocation nucleation are incorporated into a first-order constitutive model for the tensile strength of tilt boundaries. This work provides a detailed understanding of the influence of boundary structure on dislocation nucleation, which is critical for the advancement of grain boundary engineering concepts. Finally, the influence of the lattice orientation on atomistic simulations of homogeneous dislocation nucleation in single crystals is discussed.