|
1454 |
|
Tuesday, June 03, 2008, Room 04 11:10 AM Corrosion Protection 2 Corrosion protection through thermal sprayed coatings including cathodic and high temperature corrosion, coating of large areas for offshore facilities and comparable applications |
|
Corrosion of alumina-based coatings |
|
Carl Christoph Stahr* / Institute for Material and Beam Technology, IWS, Germany Lutz-Michael Berger / Fraunhofer Institute for Material and Beam Technology, Germany Mathias Herrmann/ Fraunhofer Institut für keramische Technolgien und Systeme, Germany David Deska/ Fraunhofer Institut für keramische Technolgien und Systeme, Germany |
|
Corrosion protection is a challenge of thermally sprayed coatings since long time ago. Alumina is known for its good properties regarding corrosion although especially thermally sprayed alumina-based coatings corrode if exposed to appropriate environment. The coating therefore becomes the limiting part for the component lifetime. This work shows the influence of corrosion on alumina-based coatings in dependence to the content of other oxides like TiO2 and Cr2O3 and the used coating process. The effects of corrosion are quantified which enables a lifetime prediction and tailoring of protective coatings. The coatings were analyzed using electrochemical methods and were long time exposed to bases and acids with temperatures up to the boiling point. Additionally long time exposition to pressurized water up to 200 °C was investigated. The results of this work will lead to an improved utilizability of alumina-based coatings. |