Data on various constituent binary systems were assessed in order to establish a multi-component diffusion mobility database for the face-centered cubic phase of the Ni¯Al¯Co¯Cr¯Hf¯Mo¯Re¯Ta¯Ti¯W system. The assessment relied on an existing thermodynamic database for the calculation of thermodynamic factors. The mobilities which were determined for the self-diffusion of components in the face-centered cubic phase were consistent with a relationship between the diffusivity and the melting point. A general agreement of calculated and measured diffusion coefficients in the Ni¯Co¯Cr¯Mo and Ni¯Al¯Cr¯Mo quaternary systems demonstrated the ability of the database to be extrapolated to higher-order systems. The mobility database, in conjunction with an available thermodynamic database and a finite-difference diffusion code, was used to simulate a multi-component diffusion couple between 2 commercial Ni-base superalloys.

Development of a Diffusion Mobility Database for Ni-Base Superalloys. C.E.Campbell, W.J.Boettinger, U.R.Kattner Acta Materialia, 2002, 50[4], 775-92