The quantification of the interaction between nanoclusters and dislocation motion has received relatively little experimental or theoretical research. In this work, the relationship between nanoclusters and dislocations was investigated by conducting tensile tests at different temperatures for a variety of nanoclusters in Al-Mg-Si alloys. Further, the nanoclusters were characterized by three-dimensional atom probe. The normalized energy required for a dislocation to shear through a nanocluster, go, was estimated by using the results from the tensile tests and thermal activation theory. It was possible to characterize differences in nanoclusters for different ageing times as well as changes due to the addition of Cu or Ag. Specifically, it was found that the nanoclusters that formed at 293K could be differentiated from those formed at 393K, even after correcting for the nanocluster size. Finally, it was found that the addition of small amounts of Cu or Ag fundamentally altered the dislocation-nanocluster interaction.

The Characterization of Dislocation-Nanocluster Interactions in Al-Mg-Si(-Cu/Ag) Alloys. A.Serizawa, T.Sato, W.J.Poole: Philosophical Magazine Letters, 2010, 90[4], 279-87