The diffusivity of Fe in alloys containing between 10-3 and 1.2 x 10-2wt%S was determined by the electrodeposition of a thin layer of 59Fe onto polycrystalline specimens and carrying out diffusion annealing. The volume self-diffusivity decreased with increasing S content. This decrease was more marked in the case of grain-boundary diffusion (table 186). It was suggested that the decreases were due to a decrease in the frequency of Fe/vacancy jumps in the neighborhood of a solute atom, as compared with the frequency which occurred far from the solute atoms. Another possible explanation was the intervention of more complex diffusion mechanisms with increasing concentration.

D.Treheux: Acta Metallurgica, 1982, 30[2], 563-70