A general model for multi-component diffusion in multi-phase dispersions was presented. The model was based upon multi-component diffusion data and basic thermodynamic data, and contained no adjustable parameters. No restriction was placed upon the number of components or phases that appeared in the calculations, provided that the necessary thermodynamic and kinetic data were available. The new model was implemented into a software package, and was applied to the carburization of Ni alloys and to the heat treatment of welded joints between dissimilar materials. In both cases, diffusion was associated with carbide formation or dissolution. Good agreement between experiment and calculation was found, in spite of the fact that no adjustable parameters were involved.

A.Engström, L.Höglund, J.Ågren: Metallurgical and Materials Transactions A, 1994, 25[6], 1127-34