In size-mismatched thin-film interdiffusion couples, diffusion-induced recrystallization occurred rather than conventional Fickian atomic transport. Grains formed by this process had characteristic composition levels that were so far not understood. In this work, diffusion-induced recrystallization was studied in sputter-deposited Ni/Pd films. By pre-alloying one side of the diffusion couple, the mismatch, and thus the driving force, were varied. After heat treatment, transmission electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffractometry demonstrated recrystallization. Characteristic concentration levels were derived from X-ray diffraction data. In particular, the concentration inside newly formed grains shifts coherently to the concentration inside the parent layers. It was demonstrated that the observed concentration levels were in agreement with a thermomechanical model.

Diffusion-Induced Recrystallization in Nickel/Palladium Multilayers. M.Kasprzak, D.Baither, G.Schmitz: Acta Materialia, 2011, 59[4], 1734-41