STRAIN GRADIENT RELATED UPHILL HYDROGEN DIFFUSION PHENOMENA IN PD77AG23HN

In recent studies of hydrogen diffusion in the Pd77Ag23Hn system by ab sorption techniques, uphill type non-Fickian effects have been associa ted with lattice strain gradients produced either by external mechanic al forces or by the permeating interstitials themselves. Converse down hill effects with reversed direction of permeation recorded in analogo us desorption measurements for a range of initial membrane hydrogen co ntents provide self consistent allied support for interpretations in t erms of a Gorsky effect operation which is additional to the usual Fic kian one.