Corrosion Resistant Coatings for Gas Turbine Exhaust Stack Applications

Land-based gas turbine exhaust stacks are typically made of low carbon steels, and when used in very harsh industrial environments, they are subjected to corrosion attack leading to material degradation and loss of structural integrity. To maintain acceptable condition, various types of corrosion resistant paints and coatings are used. These include aluminum-based polysiloxane organic paints, as well as wire arc sprayed stainless steel and aluminum coatings. Aqueous corrosion protection and thermal stability up to 538°C are required. Development and testing of various coating systems was conducted and presented in this paper. Laboratory and engine field-testing demonstrated the best performance for sealed aluminum wire arc sprayed coatings