An extensive transmission electron microscopic study was made of dislocation structures and particle/dislocation configurations in oxide dispersion-strengthened alloys. High-resolution transmission electron microscopy was used to characterise the particle/matrix interfaces, and in situ high-temperature deformation in a high-voltage transmission electron microscope provided some insight into the dynamic processes of dislocation detachment from particles. It was found that the dissociation of lattice dislocations into super-partials, in FeAl and Ni3Al, had important consequences for particle/dislocation interaction. That is, the super-partials were observed to surmount - and sometimes detach from - the particles separately; thus suggesting the occurrence of a cooperative effect between the partials. The in situ experiments also showed that the climb stage was rapid in comparison with dislocation detachment from the particle.
TEM Investigations of Superdislocations and their Interaction with Particles in Dispersion-Strengthened Intermetallics. R.Behr, J.Mayer, E.Arzt: Intermetallics, 1999, 7[3-4], 423-36