Hydrogen Permeation Through the Passivation Film on Iron by Time‐Lag Method

Abstract

The permeation of hydrogen through anodically passivated iron is measured at two values of hydrogen charging current density. The permeation transient is analyzed in terms of diffusion of hydrogen through iron in series with diffusion and migration of hydrogen ions through the anodic oxide, with local equilibrium at the metal‐oxide interface. The analysis yields the diffusion coefficient of hydrogen in the oxide, and the ratio of concentrations in the metal and in the oxide at the interface.