Molecular dynamics simulation using an EAM potential to explore the tension response for a nanowire with a twist grain boundary was presented here. The relationship between the grain boundary strength and the interface dislocation structure was considered. For a low angle twist grain boundary, partial dislocations nucleate from the screw dislocation at the grain boundary before yielding and the interface yields at the point when the dislocation networks lose their stability. For a high angle twist grain boundary, the interface yields at the point when the whole interface structure was disturbed and partial dislocations propagate into the grain after the yielding point. In addition, the study provided an insight into the understanding of the atomic mechanism for tension localization at the grain boundary, which was obvious for the high-angle twist grain boundary, but indistinct for the low angle twist grain boundary. The results presented could have obvious implications for the nanowire test.

Atomistic Simulations of Tension Properties for Bi-Crystal Copper with Twist Grain Boundary. X.M.Liu, X.C.You, Z.L.Liu, J.F.Nie, Z.Zhuang: Journal of Physics D, 2009, 42[3], 035404 (7pp)