Access to Uncombined Titanium through an Inhibiting Film in Sublimation Pumping of Deuterium

In principle, titanium bulk sublimator pumping should be ideal for removing large quantities of deuterium from a vacuum system. In practice, much of the depositied titanium remains uncombined and is wasted. We have demonstrated, through a series of experiments, that it is possible (by the addition of a thin layer of titanium to an apparently occluded surface) to gain access to previsouly deposited sublayers of uncombined titanium in spite of the presence of an inhibiting film (such as an oxide) on the surface.