A numerical inverse method for calculating the interdiffusion coefficients along a diffusion path in ternary systems

A numerical method has been developed to extract the composition-dependent interdiffusion coefficients from the concentration profiles in a single diffusion couple. The procedure is based on the minimization of the difference between the profiles calculated by a finite difference scheme and the experimental profiles. Tests performed on computed profiles, with noise added to simulate experimental concentration scatter, demonstrate the improvements this procedure provides compared with the classic inverse methods. In particular, the interdiffusion coefficient values are obtained along the whole diffusion path, instead of only at the intersection point of independent paths or instead of mean coefficient values.