An investigation was made of the effect of the Fe concentration upon Fe diffusion in the  phase at 1176 to 1344C. The results could be described by:

D (cm2/s) = 7.8 x 10-2 exp[-37.6(kcal/mol)/RT]

H.Nakajima, S.Ohshida, K.Nonaka, Y.Yoshida, F.E.Fujita: Scripta Materialia, 1996, 34[6], 949-53