The chemical diffusion coefficients for Cr in austenitic and ferritic steels were determined by using diffusion couples and electron probe microanalysis techniques. The average chemical volume diffusion coefficient, for compositions ranging from 14 to 28at%Cr, in the ferritic AISI446 alloy at 800 to 1000C was given by:

D (cm2/s) = 1.5 x 10-1 exp[-210(kJ/mol)/RT]

Good agreement was found with existing data on ferritic steels.

P.I.Williams, R.G.Faulkner: Journal of Materials Science, 1987, 22[10], 3537-42