Conference paper
Laboratory Investigations of Ni-Al Coatings Exposed to Conditions Simulating Biomass Firing
Fireside corrosion is a key problem when using biomass fuels in power plants. A possible solution is to apply corrosion resistant coatings. The present paper studies the corrosion and interdiffusion behaviour of a Ni-Al diffusion coating on austenitic stainless steel (TP347H). Ni-Al coatings were prepared by electrolytic deposition of nickel followed by pack aluminizing performed at 650˚C.
A uniform and dense Ni-Al coating with an outer layer of Ni2Al3 and an inner Ni layer was formed. Samples were exposed to 560°C for 168h in an atmosphere simulating biomass combustion. This resulted in localized corrosion attack. Interdiffusion was studied by isothermal heat treatment in static air at 650˚C or 700˚C for up to 3000h.
The Ni2Al3 gradually transformed into NiAl and Ni3Al during the interdiffusion process. Porosity developed at the interface between the Ni-Al coating and the Ni layer and expanded with time at both temperatures.
Language: | English |
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Year: | 2016 |
Proceedings: | 9th International Symposium on High-Temperature Corrosion and Protection of Materials |
Types: | Conference paper |
ORCIDs: | Wu, Duoli , Okoro, Sunday Chukwudi , Dahl, Kristian Vinter , Montgomery, Melanie , Pantleon, Karen and Hald, John |