|
5222 |
|
Thursday, June 08, 2017, Hall 27 11:20 AM HVAF Spraying |
|
Development of HVAF-sprayed novel Fe-based coatings for large area applications |
|
Jan Sommer* / RWTH Aachen University, Germany Kirsten Bobzin / Surface Engineering Insitute (IOT), RWTH Aachen University, Germany Mehmet Öte/ Surface Engineering Insitute (IOT), RWTH Aachen University, Germany Martin Andreas Knoch/ Surface Engineering Insitute (IOT), RWTH Aachen University, Germany |
|
Two important trends in thermal spraying are the application of novel Fe-based corrosion/wear protection coating systems and the use of fine grained powders for this purpose. 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 novel Fe-based feedstock materials are investigated. In the first step the Fe-based powders are analysed thermally using differential scanning calorimetry (DSC), to investigate the solidification and melting temperature of the powders. Furthermore, the influence of over- and under-stoichiometric air/propane-ratio on the phase composition and porosity of the resulting coatings is investigated using XRD and light microscopy. Furthermore, deposition efficiencies of HVAF coatings are investigated regarding economic aspects. |