Short-range and long-range diffusion was investigated by using magnetic after-effect and thermal desorption spectroscopy techniques, respectively. Charged samples exhibited a magnetic after-effect relaxation maximum, at 180K, which was absent from degassed samples. It was therefore attributed to local H jumps. The results indicated an activation enthalpy of 0.42eV and a pre-exponential factor of 5 x 10-12s for short-range H diffusion. The thermal desorption spectroscopic data indicated an activation enthalpy of 0.39eV for long-range H diffusion.

Hydrogen Diffusion in Dy2Fe17. N.Mommer, H.Reule, M.Hirscher, H.Kronmuller: Journal of Alloys and Compounds, 1998, 269[1-2], 39-42