Formation of an aluminium diffusion coating by surface heat treatment of an aluminium slurry sprayed metallic tube
|Period:||2014-07-01 to 2016-06-30|
|Funder:||Federal Ministry for Economics and Energy (BMWi, Germany) via AiF|
|Project Manager:||Ammar Naji|
|Research Group:||High Temperature Materials|
The aluminization by means of commercial slurries is a coating method in which the aluminium (Al) diffusion coating is developed at the substrate surface by covering it with Al slurry, followed by a heat treatment. The disadvantages of this method are that the slurry usually includes toxic chromates and phosphates, that the heat treatment process has to be carried out in an inert atmosphere for several hours, which can be a logistical challenge, and furthermore the material microstructure can be affected adversely. The goal of this project is to develop a coating process by combining a non-toxic water-based slurry with a surface heat treatment, which can be performed by induction heating, burner flame, or heating mat for several minutes at ambient atmosphere. This includes several advantages such as health and environmental compatibility, cost saving, and easier material maintenance. Experiments on specimens of iron- and nickel-based alloys have shown that closed coatings can be developed by this method. However, they consist of intermetallic phases with a high aluminium concentration. The goal of this project is to optimize the coatings by promoting the development of the β-FeAl and NiAl intermetallic phases and by adding other elements (e.g. Cr, Si, etc.) to the Al coating.back
Das IGF-Vorhaben Nr. 17026 N/1 der Forschungsvereinigung DECHEMA e.V., Theodor-Heuss-Allee 25, 60486 Frankfurt am Main wurde über die AiF im Rahmen des Programms zur Förderung der industriellen Gemeinschaftsforschung (IGF) vom Bundesministerium für Wirtschaft und Energie aufgrund eines Beschlusses des Deutschen Bundestages gefördert.