Atomistic Simulations of Interface Properties in Metals

The effects of grain boundary structure on the mechanical properties of polycrystalline aluminum are investigated by using molecular dynamics and quasicontinuum simulations. Three problems are simulated: (a) tensile deformation of nanocrystalline aluminum with different grain boundary misorientation distributions, (b) interaction between edge dislocations and tilt grain boundaries, and (c) grain boundary motion under shear deformation. It is found that the arrangements of grain boundary dislocations, which are determined not only by the misorientation angle but also by the deviation angle, strongly control the grain boundary motion; therefore, it is concluded that individual grain boundary structures influence the macroscopic mechanical properties in nanostructured materials.