it was noted that, when multiple twinning systems were activated, twin intersection became especially important since it represented the main locking mechanism which led to a reduction in the mobility of incoherent twin boundaries. Two non-equivalent types of twin intersection could arise in the L12 structure. These were the intersection lines along (1¯10] (type-I) and (¯101] (type-II) directions. However, the stress conditions for twin intersection remained unclear. In the present work, the twin-thickness dependence of type-I twin intersections in the γ-phase was reported and was attributed to the effects of various pile-ups of incident twinning partials on the twin intersections.

Twin Thickness Dependence of Type-I Twin Intersections in a γ-TiAl Based Alloy Deformed at Room Temperature. L.C.Zhang, J.G.Wang, G.L.Chen, G.Sauthoff: Journal of Materials Science Letters, 2000, 19[19], 1727-30