Konturgenaue Bauteilbeschichtung für den Verschleißschutz mittels atmosphärischen Plasmaspritzens und Lichtbogenspritzens

摘要

Abstract The Thermal Spray Technology has been an established method for the production of wear- and corrosion-resistant coatings on large even or radially symmetrically components. However, in recent years the number of complex or freeformed components to be coated has increased significantly. To achieve high quality coatings on these components all relevant parameters such as the process variables, the handling of the spray torch and the dynamic of the coating robot need to be taken into consideration carefully. The present work focuses on this problem by developing concepts for spraying near-net-shape, high quality coatings on arbitrary-formed components by means of the Thermal Spray Processes Atmospheric Plasma Spraying and Twin Wire Arc Spraying with metal matrix composite feedstocks. At first, process parameter studies are introduced, which are utilized in order to produce coatings with a dense and homogenous microstructure, a smooth surface, a good adhesion and cohesion, as well as a low thermal degradation of the carbides. The coating quality is evaluated by means of various microstructural and topographical coating characteristics. Afterwards, the most significant influencing parameters during the coating of complex components are identified and commonalities as well as fundamental differences between the two spraying processes are worked out. Furthermore, empirical models are set up in order to describe the deposition rate as a function of the various handling parameters. Finally, the knowledge gained by these studies is applied to coat various geometrical demonstrator components as well as a actual forming tool. These experiments demonstrate the assets and drawbacks of different path strategies as well as the possibilities of component coatings.