Abstract
Corrosion and erosion protection of superheaters in power
plant boilers could be improved by using thermal spray
coatings. By applying a dense coating layer over a
conventionally used material, the properties of the
component surface can be tailored more flexible based on
the environmental demands, such as erosion and corrosion.
In this paper corrosion and erosion resistance of
thermally sprayed coatings in boiler superheater
conditions is studied. HVOF coatings were tested on
aircooled probe exposure in bubbling fluidized bed (BFB)
boiler burning biofuels, recycled fuels and peat. Tested
materials were NiCr and Cr3C2-based coatings and
reference material was lowalloyed steel 10CrMo 9 10.
Exposure times were several hundred hours. Specimens were
analysed with SEM/EDX.
Deposits on superheater tubes containing e.g. potassium,
sulphur, calcium, sodium, and chlorine can cause severe
corrosion problems for conventional metal alloys. Results
of the exposure showed very good performance of coated
specimens compared to the reference material 10CrMo 9 10.
Critical factors of the coating are density and adherence
to the substrate material. Some problems may rise from
differences in thermal expansion coefficient, which can
cause crack formation in the coating.
| Original language | English |
|---|---|
| Title of host publication | Book of abstracts and Proceedings (CD-ROM) |
| Place of Publication | Lissabon |
| Publisher | European Federation of Corrosion (EFC) |
| ISBN (Print) | 972-95921-1-X |
| Publication status | Published - 2005 |
| MoE publication type | A4 Article in a conference publication |
| Event | European Corrosion Congress, Eurocorr 2005 - Lisbon, Portugal Duration: 4 Sept 2005 → 8 Sept 2005 |
Conference
| Conference | European Corrosion Congress, Eurocorr 2005 |
|---|---|
| Abbreviated title | Eurocorr 2005 |
| Country/Territory | Portugal |
| City | Lisbon |
| Period | 4/09/05 → 8/09/05 |
Keywords
- coatings
- HVOC
- high temperature corrosion
- biofuels
- boilers
