Using in situ nano-indentation, dislocation–interface interactions in Al/Nb multilayers were investigated. Preferential storage of dislocations at interfaces, as opposed to within layers, was observed. Recovery of dislocations was observed to occur through climb in the interfaces. The rapid climb of dislocations was ascribed to high vacancy diffusivity and vacancy concentration in the interfaces. The vacancy formation energy at interfaces, 0.12 eV, as estimated from the experimentally measured climb rates, was found to be significantly lower than in the bulk.

In situ TEM Observations of Room Temperature Dislocation Climb at Interfaces in Nanolayered Al/Nb Composites. N.Li, J.Wang, J.Y.Huang, A.Misra, X.Zhang: Scripta Materialia, 2010, 63[4], 363-6