The structure and energy of the Ʃ9 tilt grain boundary was analyzed by using ab initio molecular dynamics simulations based upon density functional theory. The results showed that the grain boundary had a pair of atoms which were close to each other, and that one of them moved along the grain boundary during relaxation. The grain-boundary energy was 431mJ/m2, which was smaller than that (438mJ/m2) of the Σ5 tilt grain boundary.

Analysis of Structure and Properties of Σ9 Tilt Grain Boundary in Aluminum by ab initio Molecular Dynamics. T.Kitamura, Y.Umeno: Transactions of the Japan Society of Mechanical Engineers A, 1998, 64[626], 2463-70