The atomic structures of <110> symmetrical tilt grain boundaries were investigated by means of atomistic simulations; using an embedded-atom method potential which was appropriate for Al. Attention was focussed upon examining the efficacy of the structural unit model in the context of very long period boundaries. Studies of the equilibrium and metastable structures of a number of boundaries revealed that geometrical arguments which were intrinsic to the structural unit model had to be supplemented by energetic considerations. An effective Hamiltonian was therefore introduced which estimated the energy of a string of structural units by using 2-body potentials between individual units. Results which were based upon limited input already demonstrated the effectiveness of this method. It could also be simply extended, to grain boundary structure calculations at finite temperatures, by using Monte Carlo techniques.

Structure and Energetics of Long-Period Tilt Grain Boundaries using an Effective Hamiltonian. D.N.Pawaskar, R.Miller, R.Phillips: Physical Review B, 2001, 63[21], 214105 (14pp)