Multiphase layer growth kinetics in finite gas/solid diffusion couples

A model of the diffusion kinetics in multiphase finite one-dimensional binary diffusion couples is presented. The mathematical description of the diffusion process based on the analytical solution of Fick's laws allows the time evolution of the microstructure, i.e. the number of phases present in samples and their thickness, to be predicted from the known values of diffusion coefficients and the known homogeneity ranges. Conversely, the diffusion coefficients can be calculated in ail phases of a finite sample from the movement of phase boundaries. As a first approach the HFN and Nb-C systems were treated. Copyright (C) 1996 Acta Metallurgica Inc.