Evaluation of Surface Preparation Technology for Steel Components with Fluoropolymer-based Coatings in Terms of Anti-adhesive and Mechanical Properties

The subject of the research presented in this paper was the evaluation of the technology of surface preparation of steel samples in terms of anti-adhesion and mechanical properties through the use of PFA coatings. Such coatings are used in many industries, e.g. in the manufacture and operation of metal moulds used, for example, in the production of resinous components. The specimens used in the study, which represented the surface of the moulds, were made from DC01 sheet. Six variants of release coating technology were used, differing in the number of technological operations and parameters. In the final stage, appropriate test methods were used to assess the energy properties of the coatings produced, the mechanical properties in terms of deformation of the supporting structure and the mechanical properties in terms of the effects on the coating itself. The scope of the research made it possible to determine the main properties that the manufactured coatings have in terms of their future practical applications. The results obtained for the surface free energy determined from the measurement of the surface wetting angle, the mechanical properties obtained from the three-point bending test and the evaluation of the surface quality of the coatings subjected to compressive and tensile deformations in the bending test, as well as the functional properties of the coatings in terms of their durability and adhesion determined in scratch tests, showed that the best characteristics were obtained for variant 6. This variant consisted of sequentially, after the initial stage, applying a primer layer and drying it for 15 minutes at 250°C, applying a PFA layer to the component at 150°C and then drying it for 15 minutes at 200°C and curing it for 20 minutes at 380°C. An additional layer of PFA was then applied and dried for 15 minutes at 200°C and cured for 20 minutes at 340°C. In addition, a long annealing for 3 hours at 340°C was applied in a given variant.