Molecular dynamics simulations of bicrystals were used to probe the influence of normal loading upon grain boundary shear response. A Σ11(113) Cu grain boundary was chosen to investigate grain boundary migration, while Σ9(221) and Σ27(552) grain boundaries were used to explore grain boundary sliding. The shear strengths of the Σ11(113) and Σ9(221) grain boundaries were found to be largely independent of the normal stresses acting upon the grain boundaries. However, the shear strength of the Σ27(552) grain boundary was found to be non-monotonically correlated with normal stress. The effect of intersecting partial dislocations at the grain boundary was considered for both grain boundary sliding and migration.

Effect of Normal Loading on Grain Boundary Migration and Sliding in Copper. D.H.Warner, J.F.Molinari: Modelling and Simulation in Materials Science and Engineering, 2008, 16[7], 075007 (9pp)