Average effective interdiffusion coefficients and their applications for isothermal multicomponent diffusion couples

Concentration profiles on either side of the Matano plane in a solid-solid, single phase, ternary diffusion couple can be characterized by average effective interdiffusion coefficients and characteristic depth parameters. The composition at the Matano plane is related to these coefficients and parameters. The present analysis allows the generation of concentration profiles on the basis of error function solutions that exactly reproduce the experimental interdiffusion fluxes at the Matano plane. Furthermore, from a knowledge of the average effective interdiffusion coefficients and the a parameters for one alloy side of the couple, the concentration profiles on the other alloy side may be generated. Therefore, the characterization of concentration profiles by average effective interdiffusion coefficients provides a simple and useful method for representing and generating concentration profiles in single phase multicomponent diffusion couples.