DIFFUSION OF H IN ALPHA-NBHXDY

The diffusion of H in ternary alloys α-NbHxDx, Dy was measured by means of a pulsedfieldgradient spin echo NMR technique in the temperature range from the phase boundary up to ca. 250 °C. Measurements were performed on foil specimens of four different total concentrations, x+y = 0.20, 0.50, 0.60, and 0.75, with several different H/D ratios. It was found that the diffusion coefficient of H decreases with decreasing H/D ratio for x+y= 0.20, 0.50, and 0.60, whereas it remains nearly the same for x+y = 0.75. We interpret these results as manifestation of the cooperative nature of the diffusion process that arises from the dynamical interaction between diffusing hydrogen atoms. © 1979, Akademische Verlagsgesellschaft, Wiesbaden