Induced desorption, diffusion or production of gases by 100 eV electron bombardment on some wall materials for tokamaks

In order to evaluate and to compare the surface reactions and desorption from different possible candidates for wall and limiter materials in tokamaks under electron (and ion) bombardment the cylindrical 'Triode' set-up, described at the Juelich conference, was modified by segmenting the 'anode' in five parts, each of 50 cm2 surface area: microblasted 304L stainless steel, electropolished 304L stainless steel, inconel 675, aluminium 6061 from ALCAN and graphite 5890 PT from Carbone Lorraine (already experimented as limiter material in TFR 400). (Auth.)