The permeation of H in γ titanium aluminides was studied using the Devanathan–Stachurski cell. Thin disk-shaped samples of γ TiAl with three different microstructures were appropriately prepared and cathodically charged in an aqueous 0.1N NaOH solution. The permeation current was monitored as a function of time. Permeation parameters were calculated using the time lag criterion (non-steady state lag). Values of the apparent diffusion coefficient of H in γ TiAl varying from 1.87 x 10−7cm2/s to 3.75 x 10−6cm2/s were obtained. This slight variation was attributed to differences in microstructure.

Hydrogen Permeation in Gamma Titanium Aluminides. H.A.Estupiñan, I.Uribe, P.A.Sundaram: Corrosion Science, 2006, 48[12], 4216-22