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The complete understanding of the phenomenological process related to the position of the Matano and Kirkendall plane in multicomponent system is still lacking. In this paper some aspects of Matano and lattice plane migration are studied by means of numerical simulations. New approach to calculate intrinsic diffusion coefficients in binary Ni–Au system and ternary Cu–Fe–Ni and Co–Fe–Ni is presented. Diffusivities were calculated using modified Boltzmann–Matano method. Self diffusion coefficients of the elements in diffusion couple must be known as well as position of the Kirkendall plane after the experiment to use this method. Diffusion profile was calculated using presented equations. Calculations compared with experimental data prove validity of the presented approach. This work proves that intrinsic diffusion coefficients should be given by the concentration function, not the exact value. [ABSTRACT FROM AUTHOR]

Abstract: The phenomenological Boltzmann–Matano (B–M) analysis allows approximating the concentration dependent interdiffusion coefficients related to infinite binary diffusion couple experiments. However, the complete understanding of the phenomenological process related to the Kirkendall plane position coupled with the B–M method is still lacking. A purpose of the present study is to generalize the Boltzmann–Matano analysis and propose a method of estimating the unique intrinsic diffusion coefficients of components from the experimental concentration profile and the positions of Matano and Kirkendall planes in multicomponent systems. The proposed physico-chemical approach is used to approximate the intrinsic diffusivities in a single phase of Ni–Pd binary and Cu–Fe–Ni ternary diffusion couples. [Copyright &y& Elsevier]

Abstract: The understanding of the phenomenological process related to the position of the Kirkendall plane is still lacking. In this study some aspects of Kirkendall and lattice plane migration in binary diffusion couples are studied by means of numerical simulations by the bi-velocity method. The simulations are performed using constant and composition dependent intrinsic diffusion coefficients. The results show that the position and stability of the Kirkendall plane as well as a number of other interesting features can be predicted using the entropy–density curve calculated by the bi-velocity method. [Copyright &y& Elsevier]