Adhesion of functional layers based on epoxy and polyurethane resins for aluminum substrate

Abstract The paper concerns pull-off strength test results of epoxy- and polyurethane-based coatings with three different powder fillers (carbonyl iron, ferrites, and graphite flakes). Polymer coatings were applied on an aluminum substrate that was degreased and/or pre-treated by means of abrasive blasting using electrocorundum. The roughness profile and the basic roughness parameters were determined, and the results showed a decisive effect of substrate preparation on the coating’s adhesion. The highest values of pull-off strength were obtained from epoxy (3.88 MPa) and polyurethane (3.12 MPa) coatings containing MG192 graphite flakes. During the pull-off tests a cohesive detachment mechanism was observed only between the mentioned coatings and the substrate.