Planar, high-index interphase boundaries developed during the α → γm transformation in a Ti–46.54%Al alloy were re-examined with a 3-D near-coincidence site analysis. Pairs of low-index planes, fulfilling the Zhang and Purdy minimum mismatch criterion, meet along their edges. Atoms at these edges commingle almost linearly, thereby producing a kinetic barrier to boundary migration.

Atomic Structure of High-Index α2/γm Boundaries in a Ti–46.54at%Al Alloy. W.T.Reynolds, J.F.Nie, W.Z.Zhang, J.M.Howe, H.I.Aaronson, G.R.Purdy: Scripta Materialia, 2003, 49[5], 405-9