ATOMISTIC SIMULATIONS OF [100], [110] AND [111] SYMMETRIC TILT GRAIN BOUNDARIES IN Ni3Al

The embedded atom type potentials and static relaxation method combined with the steepest descent computational technique have been used to simulate the grain boundary atomic structures, grain boundary energies, grain boundary cohesive energies, the distribution of electron density and stress field in the grain boundary region, the formation energies of vacancies and other related problems of [100], [110] and [111] symmetric tilt grain boundaries with different geometrical index and composition. Their relations with the segregation of boron, behaviors of the grain boundary, and especially the stoichiometrical effect of boron induced ductility have also been studied and discussed