材料期刊网

Using the embedded atom method interatomic potential, all Sigma < 50 tilt boundaries for hcp Ti with [0001] orientation are calculated by the method of molecular statics. Based on the atomic positions analysis, the structural units of dislocation cores are indicated. It is found that the atoms at the interfaces tend to form perfect regions and special dislocation cores, which exist in the forms of a tetrahedron and three joined irregular tetrahedra. The larger the perfect regions in one period are, the lower the grain boundary energies should be. The atomic structures of high angle (Theta > 10 degrees) tilt boundaries with Sigma = 19 and 7 are similar to those of low angle (Sigma = 37). In the relaxation procedure, the atomic positions are not changed along the [0001] for any of the boundaries discussed.