DIFFUSIVITY OF HYDROGEN IN PALLADIUM

The permeability time-lag method has been used to determine the diffusivity of hydrogen in palladium in the temperature range 496-946°C. Previous measurements had indicated a large positive deviation from Arrhenius behavior in the temperature range above 600°C. No such deviation was found in the present measurements, which are in good accord with previous determinations made at lower temperatures. The diffusivity in the temperature range 469-946°C can be represented by the equation D = D0exp(- Q RT)m2/s where D0 = (2.83 ± 0.15) × 10-7 m2/s and Q = 21.7 ± 1.3 kJ/mole. © 1979.