Schlegel Electronic Materials recommends the use of non conductive adhesives in most cases (type R).
All gaskets have a PSA width recommended according to the width of the profile to ensure sufficient direct contact at the bottom of the gasket with the application. Test was carried out according to SAE ARP 6248 (stripline method) on EW8 (9/3 mm) in order to measure the influence of non conductive PSA ( 2.5 mm and 4.5 mm wide) and conductive PSA ( 8 mm wide) .Three profiles were tested compressed at 50 % up to 40 GHz :
– EW873 + 2.5 mm R tape
– EW873 + 4.5 mm R tape
– EW873 + 8 mm D tape
Conductive PSA are usually a tradeoff between electrical conductivity and tackiness. In fact the more conductive particles embedded into the adhesive, the less tackiness and vice versa. Test results show clearly the influence of the width of the non conductive adhesive on the shielding characteristics and the poor results when the bottom surface is almost completely covered by conductive adhesive. The use of conductive adhesive should therefore be restricted to very small profiles where limited width prevent from the use of non conductive adhesive. Even for Z conductive foam, Schlegel Electronic Materialsrecommends the mounting of strips of non conductive adhesives.
