It was recalled that H dissolved in metals by occupying interstitial positions and expanding the lattice, so that a stress field was generated by the loading process. The question was addressed here of whether the stress field was responsible for the force which limited the attainment of high concentrations of H in massive Pd samples. A calculation of the H/Pd concentration showed that stress-field relaxation aided H uptake, and experimental results showed that a suitable loading path could improve the final loading ratio.

Consequences of Lattice Expansive Strain Gradients on Hydrogen Loading in Palladium A.De Ninno, V.Violante, A.La Barbera: Physical Review B, 1997, 56[5], 2417-20