The activation energy for S diffusion was deduced (table 27) from Auger electron spectroscopic data on surface segregation. It was concluded that the bulk diffusion of S in ferromagnetic α-Fe at 770 to 1000K could be described by:

D (m2/s) = 1.56 x 10-4 exp[-2.1(eV)(1+0.3R2)/kT]

where R was the ratio of spin ordering, at a given temperature, to that at absolute zero.

W.Arabczyk, M.Militzer, H.J.Müssig, J.Wieting: Scripta Metallurgica, 1986, 20[11], 1549-54