CANCELLED - Gadolinium Zirconate Overlay Solutions for Thermal Barrier Applications Exposed to CMAS Attack.

Title:

Gadolinium Zirconate Overlay Solutions for Thermal Barrier

Applications Exposed to CMAS Attack.

Abstract

With increasing gas turbine temperatures and increased focus from industry to address the issues related to calcium-magnesium-alumino-silicate (CMAS) attack, this work presents the process developments for lower conductivity, CMAS resistant coatings of Gadolinium Zirconate (GZO). These GZO coatings have been applied using both the air plasma spray (APS) and suspension plasma spray (SPS) processes, targeting multiple applications ; i.e overlay onto existing EB-PVD TBCs as well as part of a bilayer APS system. Process parameters were adjusted to tailor coating microstructures in order to balance requirements between CMAS resistance, conductivity, erosion resistance, strain tolerance and other essential criteria. Key process findings will be discussed to highlight the effects of various application techniques for coating demonstration onto components. These coating characteristics have been benchmarked against standard 7YSZ coatings, and validated by OEM testing.