Dislocations of extrinsic origin, together with trapped matrix dislocations, were observed in the twin boundaries of samples which had been deformed by 25%. Further study showed that the extrinsic dislocations were residual ones which had been left in the twin by the slip transmission of 1/3<11•0> matrix dislocations when the <11•0>{11•0} slip system in each twin crystal operated. In the case of this deformation, there was no clear sign of the presence of intrinsic twinning dislocations of normal type.

T.Kehagias, P.Komninou, G.P.Dimitrakopulos, J.G.Antonopoulos, T.Karakostas: Scripta Metallurgica et Materialia, 1994, 30[10], 1311-5