Abstract
This presentation gives an overview of a research project of the Institute of Materials Science at the University of Hannover (Germany) focussed on under water plasma spraying (UPS). The aim of this project is to qualify the process for the application of corrosion protective coatings. UPS could be used for maintenance of underwater constructions. Another field of application can be seen in an alternative for atmospheric plasma spraying (APS) in coating shops. Water is an excellent filter for noise and UV radiation. Furthermore, particle polluted water could quite easily be refined so that UPS could show environmental advantages compared to APS. The UPS process is characterized by a low standoff distance and therefore a small plasma spot. A very promising modification of the standard UPS process, which is examined in this project, is shrouded underwater plasma spraying (S-UPS). By adding the shroud to the underwater plasma spray device a large defined cavity could be build up so that spray distances comparable to APS are possible. By variation of the shroud gas in terms of air or inert gas it is possible to reach comparable or even better coating properties then using an APS process.