Internal friction of palladium containing hydrogen

Hydrogen relaxation in lutetium

“…As was shown in chapter 3, there is a difference of for the activation energies, together with a ratio of the relaxation times between the hydrogenated and the deuterated specimens. Similar effects have been reported in the literature for the systems Pd-H, D [14], Fe-H, D [25], Nb-H, D [26]. They have also been observed and treated in detail in investigations of magnetoelastic relaxation by means of the magnetic aftereffect of hydrogen in ferromagnets (for a review, see e.g.…”

“…Thus, internal-friction peaks in f.c.c. Pd(H, D)x had been attributed either to hydrogen pairing [14] or to a Zener-type rearrangement of H-interstitials and vacant interstitial sites [ 15], while a peak in H-charged austenitic stainless steel was ascribed to a hydrogen-substitutional solute atom pair [16]. The investigations of h.c.p.…”

Ultrasonic attenuation and dispersion due to hydrogen motion in the C15 Laves-phase compound TaV2Hx

“…In the Zener effect the site symmetry is such that anelastic relaxation is not expected for an isolated hydrogen; however, hydrogen-hydrogen interactions lower the site symmetry and lead to anelastic relaxation. This is the situation for the octahedral (O) site in elemental fcc metals [36][37][38][39][40][41] and the T site in elemental hexagonal metals [42][43][44][45][46]. Depending as it does on H-H interactions, the magnitude of the Zener effect [47,48] depends on the hydrogen concentration as x 2 (1 − x 2 ) if the occupancy of the sites is not far from random.…”