The apparent room-temperature diffusivity was determined by using an electrochemical permeation method. It was found that the diffusivity increased with increasing annealing time at 80C (table 35). At temperatures between 7 and 42C, the interaction energies of H atoms and lattice vacancies, and of H atoms and dislocations, were estimated to be 48.6 and 34.5kJ/mol, respectively. It was concluded that vacancies could act as deep trap sites for H at room temperature.

K.B.Kim, S.I.Pyun: Archiv für Eisenhüttenwesen, 1982, 53[10], 397-401

Table 35

Diffusivity of H in Fe