best corrosion performance the table in fig1 also shows the adhesion performance of a subsequently applied organic coating on both 2024 t3 and 7075 t6 aluminum alloys the paint adhesion performance was measured according to a wet tape paint adhesion test once dried after 14 fourteen days air curing the corresponding conversion coated panels were painted with an epoxy primer according to the mil prf 85582 standard the epoxy primer used was a water reducible epoxy primer system made of 10pw20 4 base and ecw 104 hardener according to mil prf 85582 type 1 class 2 provided by akzo nobel aerospace coatings bv two parallel 2 two inch long scratches u00be to 1 one inch apart through the coating and to the substrate were made on the panels the parallel scratches were joined with two intersecting lines or an u201c x u201d pattern the primed and scribed panels were immersed in deionized water during 24 hours prior to carrying out the wet paint adhesion tests within 2 two minutes after removing test panels from water adhesive tape was applied and pressed against the test surface with firm hand pressure and then removed the hexavalent chromium based commercial alodine 1200s exhibited the.