Multi-layers were prepared by laser deposition, and the samples were loaded electrolytically with up to 0.3H/Nb. Some were submitted to 4 complete loading-unloading cycles, and maintained in the loaded state. The microstructures of these samples, as well as those of as-prepared samples, were studied by means of high-resolution electron microscopy. After several H-loading and unloading cycles, the change in microstructure mainly involved a new dislocation arrangement. Further transmission electron microscopy revealed that β-NbH grew in columns that were parallel to the growth direction of the films after phase separation.

Influence of Hydrogen Loading on the Microstructure of Niobium-Palladium Multilayers. C.Borchers, U.Laudahn, A.Pundt, S.Fähler, H.U.Krebs, R.Kirchheim: Philosophical Magazine A, 2000, 80[3], 543-53