About this Abstract |
Meeting |
MS&T21: Materials Science & Technology
|
Symposium
|
Advanced Coatings for Wear and Corrosion Protection
|
Presentation Title |
Electroplated Ni-MMC Coatings as a Base Coating to Improve High Temperature Corrosion Caused by Sodiumvanadates |
Author(s) |
Christoph Grimme, Robin Kupec, Xabier Montero, Mathias Galetz |
On-Site Speaker (Planned) |
Christoph Grimme |
Abstract Scope |
Today’s stationary turbines often run on low grade fuels to ensure economical operation. Due to high amounts of impurities in those fuels, such as vanadium and sulfur which form low melting, aggressive sodium-vanadates during combustion cause severe hot corrosion. Up to now, this type of corrosion is mitigated by adding inhibitors, soluble in the fuel. Their reaction products form thick slags on the turbine blades which have to be removed frequently, resulting in high amounts of downtimes.
A novel coating solution is presented of inhibiting particles in a metallic NiAl or NiCrAl matrix. They react with the molten salt to high melting compounds to impede corrosion. A galvanic co-deposition process was developed for the coating application, which also offers an economical benefit over commonly used thermal spray coatings as well as the possibility to tailor the Ni-base MMC coating to the specific needs e.g. by combination with a CVD process. |