Behaviour of dislocations in TiAl intermetallics

The mechanical properties of TiAl with lamellar structure depend strongly on the interaction of crystal dislocations with the lamellar interfaces. This phenomenon is discussed with the emphasis on the role of various types of the crystal and interfacial dislocations. Strengthening by the interfaces is caused by the dislocation processes occurring at the interfaces but also by polarization of dislocation glide and deformation twinning inside the lamellae.