Affordable Access

Publisher Website

Mechanical relaxation processes of hydrogen in dilute palladium-rare earth alloys

Journal of Alloys and Compounds
Publication Date
DOI: 10.1016/s0925-8388(97)00219-3
  • Palladium-Rare Earth Alloys
  • Hydrogen Relaxation
  • Internal Friction


Abstract After charging with hydrogen, dilute Pd 100 − x RE x alloys (RE=Y, Ce, Gd) ( x = 1 … 9) show three thermally activated relaxation maxima of the internal friction between 10 and 300 K. Two of these maxima are identified as a Zener maximum of hydrogen pairs in the β-phase and as a Snoek-Köster maximum, which are both also observed in H-charged pure Pd. The third maximum appears only in the binary alloys. The activation parameters of this relaxation are τ 0 = 3·10 −12±0.5 s for me pre-exponential factor and the activation enthalpy lies between H a = 0.18 eV and H a = 0.26 eV. H a increases with increasing RE content whereas it decreases with increasing hydrogen content. The relaxation strength is independent of the RE content and depends linearly on the hydrogen concentration. These features are characteristic for the formation and reorientation of HRE (RE=Y, Ce, Gd) complexes. Furthermore, the shape factor of the strain ellipsoid of the HRE dipoles, which characterizes the anistropy and strength of the local atomic displacements, was determined as | λ 1– λ 2|=0.036.

There are no comments yet on this publication. Be the first to share your thoughts.


Seen <100 times

More articles like this

Mechanical relaxation due to hydrogen—solute compl...

on Acta Metallurgica et Materiali... Jan 01, 1995

X-ray investigations of the α-β miscibility gaps i...

on Journal of the Less Common Met... Jan 01, 1989

Hydrogen softening in some palladium-rare earth so...

on Journal of the Less Common Met... Jan 01, 1976
More articles like this..