Abstract
One important trend in thermal spraying is the application of novel Fe-based corrosion/wear protection coating systems. A typical field of application for such corrosion and abrasive wear protection coatings are rotary dryers of paper machines. At the moment, these cylinders are coated by wire arc spraying. A disadvantage of the wire arc sprayed coatings is their high thickness, which has a heat-insulation effect, and their high roughness. Therefore, an expensive post production grinding process is necessary in order to achieve the required surface quality. The goal is to develop a HVAF process that enables the production of thin, dense and near net shape corrosion/wear protection coating systems, which significantly reduce the post-production time and costs. In this study, the HVAF coating process and a novel Fe-based feedstock material are investigated. In the first step the Fe-based powder is analysed thermally using differential scanning calorimetry, to investigate the solidification and melting temperature of the feedstock material. Furthermore, the influence of the spraying distance and the powder feed rate on the microstructure and porosity of the resulting coatings is investigated using light microscopy. Furthermore, the deposition efficiency of HVAF coatings is analysed regarding their economic efficiency.
