On the basis of the thermodynamics of lattice expansion due to H insertion, interactions between H atoms and the blocking effect in H diffusion, a study was made of the profiles of H concentration and self-induced stress (and their interaction) during steady-state H diffusion through elastic membranes of face-centered cubic metals or alloys. Contrary to the accepted viewpoint, it was found that self-induced stresses suppressed departures of the concentration distribution from linearity. The residual stress profile depended upon the phase of the metal-H system. However, the diffusion flux was independent of the existence or magnitude of the self-stress. This implied that the conventional steady-state method for the measurement of diffusion coefficients could be applied experimentally even when the self-stress effect was significant. Although the results were obtained for face-centered cubic metal-H systems, the conclusions could be extended to the diffusion of other interstitials in solid samples.

Effects of Self-Induced Stress on the Steady Concentration Distribution of Hydrogen in FCC Metallic Membranes during Hydrogen Diffusion. W.S.Zhang, X.W.Zhang, Z.L.Zhang: Physical Review B, 2000, 62[13], 8884-90