Atlas aluminum “TSP”s outperform their stainless steel counterparts due, in part, to the material’s very low hydrogen permeation—seven orders of magnitude less than stainless steel.
Atlas creates a high surface vacuum environment for condensation of the Ti pumping film without producing hydrogen. Stainless steel, on the other hand, desorbs hydrogen.
A 42” wire seal chamber with loads of stainless flanges, for example, pumps down to 1×10 ¯11 in thirty hours.
