A method was developed for analyzing combined concentration profiles from multi-component solid-state diffusion data which had been obtained under free-diffusion boundary conditions. The procedure was completely analogous to the analysis of liquid-state diffusion data which were obtained from free-diffusion refractive-index profiles (such as those arising from Rayleigh interferometry). All of the data from all of the couples were least-squared as an ensemble in order to characterize the diffusion coefficient matrix. Various profile weightings provided interesting alternatives and diagnostics. Symmetrical averaging was shown to eliminate or reduce the effects of concentration dependence.

A Liquid-State Least-Squares Procedure for Obtaining Solid-State Multicomponent Diffusion Coefficients from Diffusion Couples. D.G.Miller: Acta Materialia, 1998, 46[17], 5993-9