Moessbauer investigation of Fe-Zr amorphous alloys hydrogenated after annealing

Transmission and conversion electron Moessbauer spectroscopy were used in order to get further information about the effect of hydrogenation in Fe89/Zr11 amorphous alloys in connection with the observation that the magnetically split spectrum appearing at room temperature due to a moderate hydrogenation gradually collapses with increasing hydrogen content. The Moessbauer measurements were performed on differently hydrogenated amorphous samples aged at 1500C 3000C and 6000C before the hydrogenation. The time dependence of hydrogenation has also been measured. From the changes of Moessbauer parameters depending on the annealing temperature as well as on the cathodic potential of hydrogenation (compared with the hydrogen concentration measured by gas chromatography) we can conclude that relaxation processes and structural changes, taking place in these amorphous alloys, influence the hydrogen uptake, already at relatively low temperatures. (orig.)