Straining experiments were performed in situ in order to study the mechanisms of the propagation of deformation at grain boundaries in symmetrical Σ = 3 Fe–4at%Si bicrystals with a common primary slip system in both grains. Three different orientations of the tensile axis with respect to the {112} grain-boundary plane were studied, and 3 different effects were observed. In no case was propagation of primary slip dislocations across the grain boundaries observed. When the tensile axis lay in the grain-boundary plane, the slip dislocations of the tertiary slip system entered the grain boundaries, interacted with grain-boundary dislocations and dislocations of the secondary slip system were generated in the second grain. When the angle between the primary slip plane and the grain boundaries was about 20°, the primary slip dislocations (whose Burgers vectors belonged to the grain-boundary plane) cross-slipped and followed the grain-boundary plane. Primary slip dislocations were formed in one grain, and a new sub-grain boundary was formed in the other grain when the angle between the primary slip plane and the grain boundaries was about 49°.

In situ Transmission Electron Microscopy Observation of Slip Propagation in Σ = 3 Bicrystals. J.Gemperlová, A.Jacques, A.Gemperle, T.Vystavel, N.Zárubová, M.Janecek: Materials Science and Engineering A, 2002, 324[1-2], 183-9